Brazil’s Yellow Fever outbreak: Medical stuff we should know, from NAIAD

March 9, 2017

Accurate information can be the greatest tool in the fight against diseases, infectious or vector-borne. NAIAD slide.

Accurate information can be the greatest tool in the fight against diseases, infectious or vector-borne. NAIAD slide.

Brazil endures an outbreak of Yellow Fever in early 2017. Mosquitoes transmit Yellow Fever from one mammal host to another. Famously, Yellow Fever had to be controlled to allow construction of the Panama Canal between 1910 and 1915.

It should be just a matter of days, or perhaps a few hours, before harpies on the right and in anti-science trenches demand “return” of DDT to fight this outbreak, arguing that EPA didn’t know what it was doing when it banned DDT from farm use, and probably dropping cheap shots at Rachel Carson and “environmentalists.”

Yellow Fever is usually carried by mosquitoes in the species Aedes aegypti, a nasty little bug that carries several diseases to humans including Zika virus and West Nile virus.

Distribution of Aedes aegypti mosquitoes in the U.S. Map by U.S. CDC, via Wikipedia

Distribution of Aedes aegypti mosquitoes in the U.S. Map by U.S. CDC, via Wikipedia

Astute observers know that A. aegypti are almost ubiquitous in warmer human cities, so the transmission of the disease requires only that a host (usually human) shows up infected with the pathogen, and an epidemic might occur.

Those observers also know that all mosquitoes are resistant or immune to DDT and frequently to other pesticides as well, their having been bombarded with pesticides for 60 or more years, and consequently having evolved resistance alleles. So spraying with DDT won’t work.

That’ won’t stop those who relish slandering Carson or who wish to impugn the humanity and good motives of environmentalists.

Get facts, first.

Come Dr. Anthony Fauci and Dr. Cahtharine Paules of the U.S.’s National Institute of Allergy and Infectious Diseases (NAIAD), part of the National Institutes of Health (NIH) to offer information to calm the hyperventilated, and to inform the serious and concerned citizen with an article in the New England Journal of Medicine, explaining Brazil’s problem, Yellow Fever, and what U.S. residents need to do, and this press release from NAIAD to get the key points across quickly.

Will anyone listen?

Yellow Fever in the Americas

Current Outbreak Merits Close Watch
March 8, 2017

The unusually large outbreak of yellow fever now occurring in rural Brazil deserves careful attention by world health authorities, notes Anthony S. Fauci, M.D., director of the National Institute of Allergy and Infectious Diseases (NIAID), one of the National Institutes of Health. Writing in a Perspectives piece for the New England Journal of Medicine, Dr. Fauci and his associate Catharine I. Paules, M.D., note that this latest outbreak of a serious mosquito-borne virus comes as Zika virus, which is spread by the same mosquito as yellow fever virus, continues to affect countries throughout the Americas.

Historically, yellow fever has claimed millions of lives, including many thousands in the United States. The Philadelphia epidemic of 1793, for example, killed approximately ten percent of the city’s population. In its most serious form, yellow fever symptoms include high fever, hemorrhagic manifestations, kidney failure, liver malfunction and jaundice (yellowish appearance of the eyes and skin, which gives the disease its name.)

A vaccine has been available since 1937 and confers lifelong immunity in up to 99 percent of those who receive it. Extensive immunization campaigns, along with effective mosquito control—especially in developed countries—have reduced yellow fever cases worldwide. Nevertheless, localized outbreaks in parts of Africa and Central and South America account for an estimated 84,000 to 170,000 severe cases of disease and between 29,000 and 60,000 deaths annually.

The Brazilian outbreak is a manifestation of the “sylvatic,” or jungle, transmission cycle in which forest-dwelling mosquitoes spread the virus primarily to non-human primates, with humans serving only as incidental hosts. At this time, there is no evidence that the outbreak is transforming into its “urban” cycle, but authorities should remain alert for this possibility, the authors note. In the urban cycle, yellow fever virus is usually spread by city-dwelling Aedes aegypti mosquitoes directly to people. An urban cycle of yellow fever in Angola and the Democratic Republic of Congo that began in late 2015 caused 961 confirmed cases and 137 deaths. During that outbreak, write Drs. Fauci and Paules, the world’s emergency vaccine stockpile reserve was exhausted, limiting the number of available vaccine doses and making the outbreak more difficult to control. To prevent a similar occurrence during a future yellow fever outbreak in Brazil or elsewhere, “early identification of cases and rapid implementation of public health management and prevention strategies, such as mosquito control and appropriate vaccination, are critical,” they write.

In an era of frequent international travel, an increase in domestic cases in Brazil has the potential to spread yellow fever to non-endemic areas and could pose serious disease-control challenges, Drs. Fauci and Paules observe. They urge clinicians, especially those in the United States and other places where yellow fever is uncommon, to inform themselves about yellow fever symptoms and to adopt a high index of suspicion for this diagnosis, particularly when examining travelers returning from affected regions.

ARTICLE:
CI Paules and AS Fauci. Yellow fever: Once again on the radar screen in the Americas. New England Journal of Medicine DOI: 10.1056/NEJMp1702172 (2017).

WHO:
Dr. Fauci is available to discuss this article.

CONTACT:
To schedule interviews, please contact Anne A. Oplinger, (301) 402-1663, aoplinger@niaid.nih.gov.

Map of Brazil showing confirmed cases of Yellow Fever

Map of Brazil showing confirmed cases of Yellow Fever “in the current outbreak,” as of March 2017. Information from Brazil’s Ministry of Health. NEJM image.


Good news, or great challenge? U.S. could help eliminate malaria

December 13, 2016

World Malaria Report 2016, published December 13, offers great hope in progress made against malaria in the past 16 years.

But it also notes a severe challenge: Funding to beat malaria works well, but funding pledges sometimes are not met, and progress against the disease slowed some in 2016.

In 2000, nearly a million people died from malaria worldwide. In 2015, the death toll had been cut to ~470,000, a 50% reduction in 15 years.

In 2016, ~429,000 people died from malaria. It’s 40,000 fewer people than the year before. Malaria fighters had hoped for more.

Most deaths occur in Africa, most deaths occur to children, and most deaths occur in areas where distribution of insecticide-impregnated bednets has not been complete. Distribution was slowed in 2016 by lack of funds at steps in the process, from manufacturing the nets (now done significantly in Africa) to distributing the nets, to educating people how to use them. Nets are more effective than pesticide spraying, with DDT or the other 11 approved pesticides, and considerably less expensive.

A child shows off the mosquito bednet that keeps him malaria-free. Image from Nothing But Nets.

A child shows off the mosquito bednet that keeps him malaria-free. Image from Nothing But Nets.

WHO’s press release on the Report laid out the problem, with hints at a solution.

Sustained and sufficient funding for malaria control is a serious challenge. Despite a steep increase in global investment for malaria between 2000 and 2010, funding has since flat-lined. In 2015, malaria funding totalled US$ 2.9 billion, representing only 45% of the funding milestone for 2020 (US$ 6.4 billion).

Governments of malaria-endemic countries provided about 31% of total malaria funding in 2015. The United States of America is the largest international malaria funder, accounting for about 35% of total funding in 2015, followed by the United Kingdom of Great Britain and Northern Ireland (16%).

U.S. funding was just over $1 billion. That may sound like a lot, but it’s not even a drop in the U.S. federal budget bucket.

With a doubling of the U.S. contribution to $2 billion, the U.S. could again lead the world in fighting malaria, and set a good example of American democracy in action.

In doing that, another 100,000 lives might be saved each year.

Then, U.S. would have high moral ground to urge other nations to contribute to fighting malaria, either directly through WHO or through non-governmental organizations whose work goes too-often unsung, such as Malaria No More, Nothing But ‘Nets, and the Clinton Foundation.

$10 buys a net and distribution, and a net protects a child from malaria better than spraying dangerous insecticides, for two to five years.

What are the odds the Trump administration could be recruited to beat malaria? Let’s increase those odds.


WHO’s World Malaria Report 2016 shows great progress, but funding slowdown hurts the fight against malaria

December 13, 2016

Promotional poster for the World Malaria Report 2016, from WHO

Promotional poster for the World Malaria Report 2016, from WHO; poster shows a woman and her child, protected from mosquitoes behind a bednet.

Incidence of malaria dropped to a new, all-time low in 2016, with reductions in total infections to 212 million, and a drop in malaria deaths to 429,000, worldwide. Malaria fighters had hoped the decreases would be greater.

Cover of World Malaria Report 2016, from the World Health Organization (WHO). The report has been published annually since at least 2008, tracking progress in the fight to control and eradicate malaria, one of the greatest scourge diseases in human history.

Cover of World Malaria Report 2016, from the World Health Organization (WHO). The report has been published annually since at least 2008, tracking progress in the fight to control and eradicate malaria, one of the greatest scourge diseases in human history.

This news comes from the World Health Organization’s (WHO) World Malaria Report 2016, released this morning in Geneva, Switzerland.

Of concern to readers here, the report lists ten nations still using DDT, the same number as 2015. Nine African nations and India still find some utility in DDT, though resistance to the long-used pesticide is found in almost all populations of almost all varieties of mosquito.

India remains the world’s heaviest user of DDT and the only place DDT is manufactured. The nine DDT-using African nations are Botswana, Democratic Republic of Congo, Gambia, Mozambique, Namibia, South Africa, Swaziland, Zambia, and Zimbabwe. Due to mosquito and other vector insect resistance to DDT, India will stop using DDT by 2020, and stop manufacturing at the same time.

Insecticide-impregnated bednets now are the chief tool used to prevent spread of new malaria infections. Nets have proven more effective than Indoor Residual Spraying (IRS), which has always been the chief use of DDT in the malaria fight. The report notes that mosquito resistance grows alarmingly to the preferred net pesticides, pyrethroids. Nets provide a physical barrier to mosquitoes, however, and work even when the insecticides wear off.

This years report is shorter than previous years, but still loaded with statistics and policy issues to be unpacked in the next few days.

WHO’s press release:

 

Malaria control improves for vulnerable in Africa, but global progress off-track

News release

WHO’s World Malaria Report 2016 reveals that children and pregnant women in sub-Saharan Africa have greater access to effective malaria control. Across the region, a steep increase in diagnostic testing for children and preventive treatment for pregnant women has been reported over the last 5 years. Among all populations at risk of malaria, the use of insecticide-treated nets has expanded rapidly.

But in many countries in the region, substantial gaps in programme coverage remain. Funding shortfalls and fragile health systems are undermining overall progress, jeopardizing the attainment of global targets.

Scale-up in malaria control

Sub-Saharan Africa carries a disproportionately high share of the global malaria burden. In 2015, the region was home to 90% of malaria cases and 92% of malaria deaths. Children under five years of age are particularly vulnerable, accounting for an estimated 70% of all malaria deaths.

Diagnostic testing enables health providers to rapidly detect malaria and prescribe life-saving treatment. New findings presented in the report show that, in 2015, approximately half (51%) of children with a fever seeking care at a public health facility in 22 African countries received a diagnostic test for malaria, compared to 29% in 2010.

To protect women in areas of moderate and high malaria transmission in Africa, WHO recommends “intermittent preventive treatment in pregnancy” (IPTp) with sulfadoxine-pyrimethamine. The treatment, administered at each scheduled antenatal care visit after the first trimester, can prevent maternal and infant mortality, anaemia, and the other adverse effects of malaria in pregnancy.

According to available data, there was a five-fold increase in the percentage of women receiving the recommended 3 or more doses of this preventive treatment in 20 African countries. Coverage reached 31% in 2015, up from 6% in 2010.

Insecticide-treated nets are the cornerstone of malaria prevention efforts in Africa. The report found that more than half (53%) of the population at risk in sub-Saharan Africa slept under a treated net in 2015, compared to 30% in 2010.

Last month, WHO released the findings of a major 5-year evaluation in 5 countries. The study showed that people who slept under long-lasting insecticidal nets (LLINs) had significantly lower rates of malaria infection than those who did not use a net, even though mosquitoes showed resistance to pyrethroids (the only insecticide class used in LLINs) in all of these areas.

An unfinished agenda

Malaria remains an acute public health problem, particularly in sub-Saharan Africa. According to the report, there were 212 million new cases of malaria and 429 000 deaths worldwide in 2015.

There are still substantial gaps in the coverage of core malaria control tools. In 2015, an estimated 43% of the population in sub-Saharan Africa was not protected by treated nets or indoor spraying with insecticides, the primary methods of malaria vector control.

In many countries, health systems are under-resourced and poorly accessible to those most at risk of malaria. In 2015, a large proportion (36%) of children with a fever were not taken to a health facility for care in 23 African countries.

“We are definitely seeing progress,” notes Dr. Pedro Alonso, Director of the WHO Global Malaria Programme. “But the world is still struggling to achieve the high levels of programme coverage that are needed to beat this disease.”

Global targets

At the 2015 World Health Assembly, Member States adopted the Global Technical Strategy for Malaria 2016-2030. The Strategy set ambitious targets for 2030 with milestones every 5 years to track progress.

Eliminating malaria in at least 10 countries is a milestone for 2020. The report shows that prospects for reaching this target are bright: In 2015, 10 countries and territories reported fewer than 150 indigenous cases of malaria, and a further 9 countries reported between 150 and 1000 cases.

Countries that have achieved at least 3 consecutive years of zero indigenous cases of malaria are eligible to apply for the WHO certification of malaria elimination. In recent months, the WHO Director-General certified that Kyrgyzstan and Sri Lanka had eliminated malaria.

But progress towards other key targets must be accelerated. The Strategy calls for a 40% reduction in malaria case incidence by the year 2020, compared to a 2015 baseline. According to the report, less than half (40) of the 91 countries and territories with malaria are on track to achieve this milestone. Progress has been particularly slow in countries with a high malaria burden.

An urgent need for more funding

Sustained and sufficient funding for malaria control is a serious challenge. Despite a steep increase in global investment for malaria between 2000 and 2010, funding has since flat-lined. In 2015, malaria funding totalled US$ 2.9 billion, representing only 45% of the funding milestone for 2020 (US$ 6.4 billion).

Governments of malaria-endemic countries provided about 31% of total malaria funding in 2015. The United States of America is the largest international malaria funder, accounting for about 35% of total funding in 2015, followed by the United Kingdom of Great Britain and Northern Ireland (16%).

If global targets are to be met, funding from both domestic and international sources must increase substantially.

Note to editors

RTS,S/AS01 malaria vaccine

Last month, WHO announced that the world’s first malaria vaccine would be rolled out through pilot projects in 3 countries in sub-Saharan Africa. Vaccinations will begin 2018. The vaccine, known as RTS,S, acts against P. falciparum, the most deadly malaria parasite globally, and the most prevalent in Africa. Advanced clinical trials have shown RTS,S to provide partial protection against malaria in young children.

WHO multi-country evaluation on LLINs

On 16 November 2016, WHO released the findings of a 5-year evaluation conducted in 340 locations across 5 countries: Benin, Cameroon, India, Kenya and Sudan. The findings of this study reaffirm the WHO recommendation of universal LLIN coverage for all populations at risk of malaria.

Will major media cover this news? Will your local newspapers and broadcast outlets even make note?

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DDT FAIL: Mosquito-borne diseases deplete medical care in DDT’s world capital

September 15, 2016

India News Today photo shows insecticide fogging in crowded Delhi neighborhoods to combat Chikungunya virus by striking down mosquitoes that transmit the disease from one human to another.

India News Today photo shows insecticide fogging in crowded Delhi neighborhoods to combat Chikungunya virus by striking down mosquitoes that transmit the disease from one human to another.

In the western world, libertarians, so-called conservatives and anti-science people call for a “return” of DDT to fight Zika virus spread.

But in the world’s DDT capital, India, where DDT is still made and more DDT is applied than in the rest of the world combined, DDT’s failures stand out. News reports say health care in key Indian cities is hamstrung by doctors and nurses getting mosquito-borne diseases.

Why don’t they just use “the magic powder,” DDT, to wipe out mosquitoes? Oh, Dear Reader, India has used DDT extensively, for everything, for 60 years. Mosquitoes that carry disease, and all other mosquitoes, and many other insect pests, developed resistance and immunity to DDT from that use.

Apart from the fact that DDT would be the WRONG pesticide to use for anything other than malaria-carrying mosquitoes from the genus Anopheles, it simply does not work.

If DDT advocates paid attention to news and history, they’d not call for more DDT anywhere for any reason.

India Today detailed the simmering crisis in Delhi in a story headlined, “Dengue-chinkungunya outbreak takes down doctor, nurses and sanitation workers”:

Subhead:

Apart from doctors, even nurses, other members of the medical staff and sanitation workers are going on leave at a time when the number of people afflicted by dengue and chikungunya this year in the city and its suburbs has crossed two thousand.

As outcry over an onslaught of viral diseases in the Capital reaches fever pitch and hospitals struggle in the face of an unrelenting tide of patients, the men in white too have started calling in sick.

Apart from doctors, even nurses, other members of the medical staff and sanitation workers are going on leave at a time when the number of people afflicted by dengue and chikungunya this year in the city and its suburbs has crossed two thousand.

Malaria is carried almost always by Anopheles, but chikungunya is carried by two species of Aedes, Aedes aegypti and Aedes albopictus. These mosquitoes also carry dengue fever and Yellow fever. A. aegypti is the principal carrier of the Zika virus, worldwide. Health workers being felled by dengue and chikungunya tells us the area would also be fertile territory for the spread of Zika virus, if it were introduced there.

Careful watchers, therefore, will understand that DDT has worn out its usefulness against a wide variety of mosquito-borne diseases including Zika.

“In our hospital, 10 per cent of the staff is currently down with fever,” said Dr Ramesh Chugh, medical superintendent of Pt Madan Mohan Malaviya Hospital in south Delhi. “We have over 100 doctors, and currently 7-8 doctors are down with fever.”

Experts say heavier than usual rainfall, a large number of construction projects and scores of open drains in Delhi are allowing mosquitoes to breed in stagnant water.

Far too many commenters fail to understand that DDT was never the chief tool in fighting malaria, or any other disease. Instead, DDT was used to knock down local populations of mosquitoes, temporarily, so health care and better housing and other measures could cure humans of the diseases and remove mosquito breeding areas from areas around human homes and human activities. India’s failure to provide good sewage drainage, good storm sewage drainage, and otherwise plug up potholes and even tiny water catching places allows mosquitoes almost free rein. India relied too long on poisoning everything with DDT, instead of building a mosquito-resistant urban area.

At Lok Nayak Hospital in central Delhi, 18 doctors are on leave. “Either the doctors are down with fever or somebody in their family is ill. The doctors are taking leave for at least 4-5 days. We have had cases where physicians were ill but returned to work early seeing the number of patients,” said a senior doctor.

NURSES AND SANITATION WORKERS ALSO ON LEAVE

In east Delhi’s Lal Bahadur Shastri Hospital, 18 members of the medical staff, including doctors, nurses and sanitation workers, are absent. “In a staff of nearly 1200, 10-15 doctors are on leave due to viral illnesses,” said Dr Punita Mahajan, medical superintendent of Baba Ambedkar Hospital in northwest Delhi. “We are not exerting pressure on the doctors to continue if they feel slightly unwell as it is very important for the hospital to ensure that they remain healthy.”

The Delhi government has asked hospitals to ensure that dengue and chikungunya patients are treated without distress.

Officials say the health department has already dedicated an additional 1,000 beds for those suffering from fever at the Rajiv Gandhi Super Speciality Hospital, Janakpuri Super Speciality Hospital and Deep Chand Bandhu Hospital.

These institutes have been designated nodal hospitals for fever in the city. All hospitals- government and private – in the National Capital Territory have been directed to increase their surge capacity.

“While doctors are trying their best to remain on duty till the effect of vector-borne diseases recedes the city, the shortage in staff and the new directions from the government would add to the existing burden,” said a doctor on condition of anonymity.

The Delhi government says it is fully prepared to battle with the onslaught of diseases and has denied in the city high court claims that the Capital is facing its worst dengue crisis.

In an affidavit filed in the court, it said strict surveillance of preparedness and impact of these diseases has been carried out for taking further preventive measures as, due to environmental conditions, the number of diseases such as dengue, chikungunya and malaria shows an upswing during July to October.

India continues to learn that DDT is not magic, not often useful, and sometimes detrimental to disease control efforts.

Will the rest of the world watch and learn? No, DDT will not and cannot help in the fight against Zika virus’s spread to humans. Waste no more time wondering, but get on with the hard work of draining mosquito breeding places, improving houses with window screens and other improvements, and developing vaccines and other medicines. Now.

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Resources for World Malaria Day 2013

April 25, 2013

Not a word about condemning Rachel Carson.  No plea to use DDT to try to poison Africa or Asia to health.  That’s a great start.

More:

Mother and son under a protective bednet, the most efficient method to prevent malaria.  Columbia University MVSim image

Mother and son under a protective bednet, the most efficient method to prevent malaria. Columbia University MVSim image


V for Vaccine: A slightly rude film with a powerful point

January 10, 2013

A couple of kids in the Dallas area have died already from influenza — neither had been vaccinated against it.  Deaths have occurred across the nation, frequently in young, otherwise healthy people.

Nasty flu bugs going around this year, and the every-year epidemic has hit about two months early.  One part of the good news is that the vaccines this year are especially well-suited to target the viruses that cause the trouble.  The vaccines work well every year, but especially well in 2012 and 2013.

The bad news is that millions of people haven’t bothered to get vaccinated. That’s not good.

  1. Under Obamacare, there’s no copay for insurance for a flu shot.  It’s “free” if you have any kind of insurance. In addition, county health offices offer the vaccines for free to any comers.  A couple of weeks ago at the pharmacy I stood behind a woman who confessed she’d not gotten a flu shot (pharmacies are pushing vaccinations these days, to promote their mini-clinics).  “I’ve got that crappy teachers’ insurance,” she told the technician.  “It never pays for anything like that.”  The tech looked it up, and told her that her copay was zero, and her insurance paid for it — essentially a free shot, to her.  On the way into the clinic she said, “I’ve never gotten a flu shot before.”  Oy.
  2. Think Herd Immunity:  Are you usually healthy?  Great.  But if you’re pregnant, or you work around people who are or may be pregnant, or if you’re over 60, or if you have any chronic condition like diabetes, high blood pressure, chronic sinusitis, or a raft of other things, you’re at risk, and you put others in those risk categories at risk.  My grandfather worked at a hospital while my mother and my oldest brother were living with him; after a week of my grandfather’s working in the polio ward, my brother came down with the disease.  Of course we don’t know for sure, but my grandfather kicked himself for 40 years, until his death, because he thought he’d brought home the disease my brother caught.  With vaccines, those incidents become much more rare.

Risking this blog’s G rating, I’m going to post this film, “V for Vaccine.”  Found it at New Anthropocene.  Turn up your offense filter, or ignore the language — but pay attention to what this guy says, PowerM1985:

Is it worth getting your children vaccinated if it risked them becoming autistic? In this video I give a short demonstration of why I personally believe that even if there was a risk of my child becoming autistic (AND THERE IS NOT!) I would still get them vaccinated.

You should probably know that the work of the Centers for Disease Control to correctly predict which strains of the viruses will be most prevalent, and get vaccines that will fight those viruses, has been very, very good this year.

  • Influenza A (H3N2), 2009 influenza A (H1N1), and influenza B viruses have all been identified in the U.S. this season. During the week of December 23-29, 2,346 of the 2,961 influenza positive tests reported to CDC were influenza A and 615 were influenza B viruses. Of the 1,234 influenza A viruses that were subtyped, 98% were H3 viruses and 2% were 2009 H1N1 viruses.
  • Since October 1, 2012, CDC has antigenically characterized 413 influenza viruses, including 17 2009 influenza A (H1N1) viruses, 281 influenza A (H3N2) viruses and 115 influenza B viruses.
    • All 17 of the 2009 influenza A (H1N1) viruses were characterized as A/California/7/2009-like. This is the influenza A (H1N1) component of the Northern Hemisphere vaccine for the 2012-2013 season.
    • Of the 281 influenza A (H3N2) viruses, 279 (99%) were characterized as A/Victoria/361/2011-like. This is the influenza A (H3N2) component of the Northern Hemisphere influenza vaccine for the 2012-2013 season.
    • Approximately 69% of the 115 influenza B viruses belonged to the B/Yamagata lineage of viruses, and were characterized as B/Wisconsin/1/2010-like, the influenza B component for the 2012-2013 Northern Hemisphere influenza vaccine. The remaining 31% of the tested influenza B viruses belonged to the B/Victoria lineage of viruses.

What are you waiting for?  Go get a flu shot!

More:

English: This is CDC Clinic Chief Nurse Lee An...

This is CDC Clinic Chief Nurse Lee Ann Jean-Louis extracting Influenza Virus Vaccine, Fluzone® from a 5 ml. vial. (Photo credit: Wikipedia)

Graphic on influenza, 2013 - Flu.gov

Information from Flu.gov; click image to get to active Flu Vaccine Finder


Still no ban on DDT: Treaty monitors allow DDT use to continue

December 16, 2012

Real news on a topic like DDT takes a while to filter into the public sphere, especially with interest groups, lobbyists and Astro-Turf groups working hard to fuzz up the messages.

News from the DDT Expert Group of the Conference of the Parties to the Stockholm Convention was posted recently at the Stockholm Convention website — the meeting was held in early December in Geneva, Switzerland.

Stockholm Convention on Persistent Organic Pol...

Logo of the Stockholm Convention on Persistent Organic Pollutants (POPs Treaty) Wikipedia image

In the stuffy talk of international relations, the Stockholm Convention in this case refers to a treaty put into effect in 2001, sometimes known as the Persistent Organic Pollutants Treaty (POPs).  Now with more than 152 signatory nations and 178 entities offering some sort of ratification (not the U.S., sadly), the treaty urges control of chemicals that do not quickly break down once released into the environment, and which often end up as pollutants.  In setting up the agreement, there was a list of a dozen particularly nasty chemicals branded the “Dirty Dozen” particularly targeted for control due to their perniciousness — DDT was one of that group.

DDT can still play a role in fighting some insect-carried diseases, like malaria.  Since the treaty was worked out through the UN’s health arm, the World Health Organization (WHO), it holds a special reservation for DDT, keeping DDT available for use to fight disease.   Six years ago WHO developed a group to monitor DDT specifically, looking at whether it is still needed or whether its special provisions should be dropped.  The DDT Expert Group meets every two years.

Here’s the press release on the most recent meeting:

Stockholm Convention continues to allow DDT use for disease vector control

Fourth meeting of the DDT Expert Group assesses continued need for DDT, 3–5 December 2012, Geneva

Mosqutio larvae, image from WHO

Mosqutio larvae, WHO image

The Conference of the Parties to the Stockholm Convention, under the guidance of the World Health Organization (WHO), allows the use of the insecticide DDT in disease vector control to protect public health.

Mosquito larvae

The Stockholm Convention lists dichlorodiphenyltrichloroethane, better known at DDT, in its Annex B to restrict its production and use except for Parties that have notified the Secretariat of their intention to produce and /or use it for disease vector control. With the goal of reducing and ultimately eliminating the use of DDT, the Convention requires that the Conference of the Parties shall encourage each Party using DDT to develop and implement an action plan as part of the implementation plan of its obligation of the Convention.

At its fifth meeting held in April 2011, the Conference of the Parties to the Convention concluded that “countries that are relying on DDT for disease vector control may need to continue such use until locally appropriate and cost-effective alternatives are available for a sustainable transition away from DDT.” It also decided to evaluate the continued need for DDT for disease vector control at the sixth meeting of the Conference of the Parties “with the objective of accelerating the identification and development of locally appropriate cost-effective and safe alternatives.”

The DDT Expert Group was established in 2006 by the Conference of the Parties. The Group is mandated to assess, every two years, in consultation with the World Health Organization, the available scientific, technical, environmental and economic information related to production and use of DDT for consideration by the Conference of the Parties to the Stockholm Convention in its evaluation of continued need for DDT for disease vector control.

The fourth meeting of the DDT Expert Group reviewed as part of this ongoing assessment:

  1. Insecticide resistance (DDT and alternatives)
  2. New alternative products, including the work of the Persistent Organic Pollutants Review Committee
  3. Transition from DDT in disease vector control
  4. Decision support tool for vector control.

The DDT expert group recognized that there is a continued need for DDT in specific settings for disease vector control where effective or safer alternatives are still lacking. It recommended that the use of DDT in Indoor Residual Spray should be limited only to the most appropriate situations based on operational feasibility, epidemiological impact of disease transmission, entomological data and insecticide resistance management. It also recommended that countries should undertake further research and implementation of non-chemical methods and strategies for disease vector control to supplement reduced reliance on DDT.

The findings of the DDT Expert Group’s will be presented at the sixth meeting of the Conference of the Parties, being held back-to-back with the meetings of the conferences of the parties to the Rotterdam and Basel conventions, from 28 April to 11 May 2013, in Geneva.

Nothing too exciting.  Environmentalists should note DDT is still available for use, where need is great.  Use should be carefully controlled.  Pro-DDT propagandists should note, but won’t, that there is no ban on DDT yet, and that DDT is still available to fight malaria, wherever health workers make a determination it can work.  If anyone is really paying attention, this is one more complete and total refutation of the DDT Ban Hoax.

Rachel Carson’s ghost expresses concern that there is not yet a safe substitute for DDT to fight malaria, but is gratified that disease fighters and serious scientists now follow the concepts of safe chemical use she urged in 1962.

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Laissez Faire Today, lazy and unfair as yesterday on issues of DDT

September 25, 2012

In June [2012] I drew encouragement that Henry I. Miller, the musty old anti-science physician at the Hoover Institution, had not renewed his annual plea to bring back DDT.  Miller is just one of the most predictable trolls of science and history; most years he waits until there are a number of West Nile virus victims, and then he claims we could have prevented it had we just jailed Rachel Carson and poisoned the hell out of America, Africa, Asia and the Moon with DDT.  For years I’ve reminded him in various fora that DDT is particularly inappropriate for West Nile . . .

Rachel Carson Homestead Springdale, PA

Rachel Carson Homestead Springdale, Pennsylvania (Photo credit: Wikipedia)

Since June, Miller popped up and popped off in Forbes, but using the event of the 50th anniversary of Rachel Carson’s brilliant book Silent Spring.  Brilliance and science and history aside, Miller still believes that protecting wildlife and humans from DDT’s manifold harms is a threat to free enterprise — how can anyone be expected to make a profit if they can’t poison their customers?

Miller is not the only throwback to the time before the Age of Reason, though.  It’s time to put the rebuttals on the record, again.

Comes this morning Jeffrey Tucker of Laissez Faire Today, complaining that the resurgence of bedbugs in America is an assault on democracy, apple pie, free enterprise, and Rachel Carson should be exhumed and tortured for her personal banning of DDT worldwide.  You can read his screed.  He’s full of unrighteous and unholy indignation at imagined faults of Carson and imagined benignity of pesticides.

I responded (links added here):

I’m shocked by your mischaracterizations of Rachel Carson, her great book Silent Spring (which it appears to me you didn’t read and don’t know at all), and pesticide regulation. Consequently, you err in history and science, and conclusion. Let me detail the hub of your errors.

You wrote:

Carson decried the idea that man should rule nature. “Only within the moment of time represented by the present century has one species — man — acquired significant power to alter the nature of the world.” This anthropocentrism she decried.

Carson was concerned that we were changing things that would have greater effects later, and that those effects would hurt humans. Her concern was entirely anthropocentric: What makes life worth living? Should we use chemicals that kill our children, cripple us, and create havoc in the things we enjoy in the outdoors, especially if we don’t know the ultimate effects?

Exactly contrary to your claim, her book was directed at the quality and quantity of human lives. She wanted long, good lives, for more people. How could you miss that, if you read any of her writings?

She suggested that killing a bedbug is no different from killing your neighbor: “Until we have the courage to recognize cruelty for what it is — whether its victim is human or animal — we cannot expect things to be much better in this world… We cannot have peace among men whose hearts delight in killing any living creature.”

Carson never wrote that there should be difficulty in killing bedbugs. The passage you quote, but conspiratorially do not cite, comes not from Silent Spring, but from a commentary on a compilation of hunting stories.* She’s referring to killing for the sake of killing, in that passage. I think it’s rather dishonest to claim she equates fighting biting bedbugs with killing animals unsportingly. I worry that you find it necessary to so grossly and dishonestly overstate your case. Is your case so weak?

In fact, she spoke of animals in patently untrue ways: “These creatures are innocent of any harm to man. Indeed, by their very existence they and their fellows make his life more pleasant.”

She did not write that about bedbugs. That’s a false claim.**

I guess she never heard of the Black Death.

I guess you never heard of accuracy. On page 266 of Silent Spring Carson directly addressed plague in a list of insect- and arthropod-borne diseases; Carson wrote:

“The list of diseases and their insect carriers, or vectors, includes typhus and body lice, plague and rat fleas, African sleeping sickness and tsetse flies, various fevers and ticks, and innumerable others.

“These are important problems and must be met. No responsible person contends that insect-borne disease should be ignored. The question that has now urgently presented itself is whether it is either wise or responsible to attack the problem by methods that are making it worse.” (Silent Spring, page 266)

Carson describes abuse of pesticides — such as DDT on bedbugs — that actually makes the insects stronger and tougher to get rid of. That appears to be your stand, now, to do whatever Carson said not to do, in order to poke a thumb in her eye, even if it means making bedbugs worse.

[Tucker continued:] In short, she [Rachel Carson] seemed to suggest that bedbugs — among all the millions of other killer insects in the world — enjoy some kind of right to life. It was a theory that could be embraced only in a world without malaria and bedbugs. But embraced it was.

That’s total fiction. What you write is completely divorced from fact.

By 1972, DDT was banned. And not only DDT. The whole enterprise of coming up with better and better ways to further human life and protect its flourishing was hobbled.

By 1960, DDT had ceased to work against bedbugs — this was one of the things that worried Carson*** and would worry any responsible person [see Bug Girl’s blog]. In her book, Carson warned that indiscriminate use and abuse of DDT would render it useless to fight disease and other insects and pests. By 1965, super mosquito-fighter Fred Soper and the World Health Organization had to stop their campaign to eradicate malaria when they discovered that abuse of DDT in agriculture and other uses had bred malaria-carrying mosquitoes in central and Subsaharan Africa that were resistant and immune to DDT. Keep in mind that the U.S. ban on DDT applied only in the U.S., and only one other nation in the world had a similar ban. DDT has never been banned in Africa, nor Asia.

Carson sounded the warning in 1962. By 1972, when the U.S. banned use of DDT on agricultural crops (and only on crops), it was too late to preserve DDT as a key tool to wipe out malaria.

Was the pesticide industry “hobbled?” Not at all. EPA’s order on DDT explicitly left manufacturing in the U.S. available for export — keeping profits with the pesticide companies, and multiplying the stocks of DDT available to fight disease anywhere in the world that anyone wanted to use it.

The fact is that DDT was a fortunate find, a bit of a miracle substance, and we overused it, thereby cutting short by decades its career as a human life-saver. That was exactly what Carson feared, that human lives would be lost and made miserable, unnecessarily and prematurely, by unthinking use of chemical substances. Pesticide manufacturers have been unable to come up with a second DDT, but not because regulation prevents it. Carson understood that.

There is no shortage of science-ignorant, and science-abusive websites that claim Rachel Carson erred. But 50 years out, the judgment of the President’s Science Advisory Council on her book remains valid: It’s accurate, and correct, and we need to pay attention to what she wrote. Not a jot nor tittle of what Carson wrote in 1962 has proven to be in error. Quite the contrary, as Discover Magazine noted in 2007, thousands of peer-reviewed studies reinforce the science she cited then.

Malaria deaths today are at the lowest level in human history, largely without DDT, and much due to malaria fighters having adopted the methods of fighting the disease that Carson advocated in 1962. Unfortunately, those methods were not adopted for nearly 40 years. Still, the reductions in malaria are remarkable. At peak DDT use in 1959 and 1960, a half-billion people in the world got malaria every year, one-sixth of the world’s people. 4 million died from the disease. In 2009, about 250 million people got malaria — a reduction of 50% in infections — and fewer than 800,000 people died — a dramatic reduction of more than 75% in death toll. This is all the more remarkable when we realize that world population more than doubled in the interim, and at least a billion more people now live in malaria-endemic areas. Much or most of that progress has been without DDT, of necessity — every mosquito on Earth today now carries the alleles of resistance and immunity to DDT.

You impugn a great scientist and wonderful writer on false grounds, and to damaging effect. I hope you’re not so careless in other research.

Rachel Carson was right. The re-emergence of bedbugs, 50 years after she wrote, is not due to anything Carson said, but is instead due to people who petulantly refused to listen to her careful and hard citations to science, and exhortations to stick to what we know to be true to protect human health and the quality of life.

_____________

* Rachel Carson: Legacy and Challenge, by Lisa H. Sideris, Kathleen Dean Moore, citing another of Carson’s writings, a critique of a collection of Aldo Leopold’s essays on hunting, Round River.

**  Here is the full quote, from pages 99-100 of Silent Spring, highlights added here:

Incidents like the eastern Illinois spraying raise a question that is not only scientific but moral. The question is whether any civilization can wage relentless war on life without destroying itself, and without losing the right to be called civilized. These insecticides are not selective poisons; they do not single out the one species of which we desire to be rid. Each of them is used for the simple reason that it is a deadly poison. It therefore poisons all life with which it comes in contact: the cat beloved of some family, the farmer’s cattle, the rabbit in the field, and the horned lark out of the sky. These creatures are innocent of any harm to man. Indeed, by their very existence they and their fellows make his life more pleasant. Yet he rewards them with a death that is not only sudden but horrible. Scientific observers at Sheldon described the symptoms of a meadowlark found near death: ‘Although it lacked muscular coordination and could not fly or stand, it continued to beat its wings and clutch with its toes while lying on its side. Its beak was held open and breathing was labored.’ Even more pitiful was the mute testimony of the dead ground squirrels, which ‘exhibited a characteristic attitude in death. The back was bowed, and the forelegs with the toes of the feet tightly clenched were drawn close to the thorax…The head and neck were outstretched and the mouth often contained dirt, suggesting that the dying animal had been biting at the ground.’

***  See page 273 of Silent Spring.

More:


Why you should be concerned about mercury pollution

December 28, 2011

Mercury poisoning marches through our culture with a 400-year-old trail, at least.  “Mad as a hatter” refers to the nerve damage hatmakers in Europe demonstrated, nerve damage we now know came from mercury poisoning.

In the 20th century annals of pollution control, the Minimata disaster stands as a monument to unintended grotesque consequences of pollution, of mercury poisoning.

A key Japanese documentary on the disaster is now available from Zakka Films on DVD, with English subtitles.

Anyone who scoffs at EPA’s four-decades of work to reduce mercury pollution should watch this film before bellyaching about damage to industry if we don’t allow industry to kill babies and kittens in blind, immoral pursuit of profit at public expense.

American Elephants, for example, is both shameless and reckless  in concocting lies about mercury pollution regulation (that site will not allow comments that do not sing in harmony with the pro-pollution campaign (I’d love for someone to prove me wrong)).  Almost every claim made at that post is false.  Mercury is not harmless; mercury from broken CFL bulbs cannot begin to compare to mercury in fish and other animals; mercury pollution is not minuscule (mercury warnings stand in all 48 contiguous states, warning against consumption of certain fish).  President Obama has never urged anything but support for the coal-fired power industry — although he has expressed concerns about pollution, as any sane human would.

Republicans have lost their moral compass, and that loss is demonstrated in the unholy campaign for pollution, the campaign against reducing mercury emissions.  It’s tragic.  Action will be required in November to stop the tragedy from spreading.  Will Americans respond as they should at the ballot boxes?

Can you watch “Minimata:  The Victims and Their World,” and not urge stronger controls on mercury emissions?  Can you support the murder of children and workers, for profit?


Fighting malaria with indoor use of insecticides, with USAID money

September 18, 2011

Short video demonstrating the Indoor Residual Spraying program in Mali, financed by funding from the U.S. Agency for International Development (USAID).  Note there is no ban on DDT, note that fighting malaria, even with poisons for mosquitoes, requires more than just spraying poison.

The video is in French.

539 views, September 18, 2011

President’s Malaria Initiative: Plans for FY 2011

December 14, 2010

Barack Obama continued George W. Bush’s Africa-oriented fight against malaria.  The President’s Malaria Initiative (PMI)continues to target malaria for control and, if possible, eradication.

PMI announced today plans for work in 2011, country by country:

Malaria Operational Plans for Fiscal Year 2011

These Malaria Operational Plans have been endorsed by the U.S. Global Malaria Coordinator and reflect collaborative discussions with the national malaria control programs and partners in country. If any further changes are made to these plans, it will be reflected in revised postings.

How long before some wag complains that Obama’s program is anti-Africa because it doesn’t propose enough poisoning of the place?  “Not enough DDT!” they will complain, I wager.  And, for the record, I make this prediction not having read any of the country operational plans — in nearly complete ignorance of what the plans actually propose.  Can you find “enough” DDT in any country’s plan?

More:


Mandy Moore Talks Mosquito Nets – ABC News

December 13, 2010

Don’t ask me what work she’s done, because I couldn’t tell you.  I can tell — based on the headlines of the clipping services — that Mandy Moore is popular.

Ironically, in her brief tour of Africa and — shall we label it? — probably-shallow understanding of the issues, Ms. Moore has a deeper understanding of malaria and how to fight it than the most erudite of the DDT denialists, like Michael Crichton, or Rutledge Taylor.  Innocence wins.

For ABC News, the actress talked about charity work in Africa:

Vodpod videos no longer available.

Mandy Moore Talks Mosquito Nets – ABC News, posted with vodpod

It’s a case of a celebrity doing “Do a Good Deed” duty, most likely.  In the video, Mandy Moore puts DDT denialists to shame.  In writing?  Moore doesn’t come off as well.  (Did she write that piece herself?  Maybe she should write what she talks.)


Do bednets make a difference?

September 4, 2010

Go see these two Associated Press photos from Pakistan, at MSNBC’s site — same location, same day.


DDT and birth defects: South African television asks questions

July 23, 2010

Steven Milloy, Roger Bate, and Richard Tren hope you never see this television production — they hope you never even hear about it.  It’s one more indication that Rachel Carson was right.

They hope you never even hear about it.  It’s set for telecast in South Africa next Tuesday:

Special Assignment to broadcast episode on ‘Collateral Damage’

Published: 22 July 2010

This week, Special Assignment looks at those affected by the dangerous DDT chemical and also those who say it is a necessary evil to prevent many South Africans from dying.

“I have problems with my balls,” says ‘George’. “I was born without testicles,” adds ‘Joseph’, yet another man born in the Limpopo area. These two and many other young men in Venda share a common story.

Each year, South Africa sprays more than 90 tonnes of the toxic DDT chemical in homesteads in KwaZulu-Natal and Limpopo areas. Though DDT, a persistent organic chemical which can remain in the environment for as much as 40 years is banned across the world, South Africa still uses it to control malaria in the country. Recent studies have however showed that DDT is harmful to humans with hundreds of kids born in the Venda area showing signs of genital deformities. The chemical has also been associated with breast cancer; diabetes; and spontaneous abortion. Yet it remains South Africa’s best option for the prevention of malaria which kills millions of people each year across Africa. This week, Special Assignment looks at those affected by this chemical and also those who say it is a necessary evil to prevent many other South Africans from dying.

‘Collateral Damage’ will be broadcast on Special Assignment on Tuesday, 27 July, at 20:31 on SABC3.


University of Arizona’s “malaria-proof” mosquito

July 15, 2010

This could be good news:  A genetically-altered mosquito that doesn’t harbor the malaria parasite, and so cannot pass it along to humans it bites in its later life.

One more way to end the use and production of DDT.

Press release from the University of Arizona (one of my alma mater schools):

The first malaria-proof mosquito

Scientists at the University of Arizona have achieved a breakthrough in the fight against malaria: a mosquito that can no longer give the disease to humans

IMAGE: Michael Riehle, holding genetically altered mosquitoes, and his team work in a highly secure lab environment to prevent genetically altered mosquitoes from escaping.

Click here for more information.

For years, researchers worldwide have attempted to create genetically altered mosquitoes that cannot infect humans with malaria. Those efforts fell short because the mosquitoes still were capable of transmitting the disease-causing pathogen, only in lower numbers.

Now for the first time, University of Arizona entomologists have succeeded in genetically altering mosquitoes in a way that renders them completely immune to the parasite, a single-celled organism called Plasmodium. Someday researchers hope to replace wild mosquitoes with lab-bred populations unable to act as vectors, i.e. transmit the malaria-causing parasite.

“If you want to effectively stop the spreading of the malaria parasite, you need mosquitoes that are no less than 100 percent resistant to it. If a single parasite slips through and infects a human, the whole approach will be doomed to fail,” said Michael Riehle, who led the research effort, the results of which will be published July 15 in the journal Public Library of Science Pathogens. Riehle is a professor of entomology in the UA’s College of Agriculture and Life Sciences and is a member of the BIO5 Institute.

Riehle’s team used molecular biology techniques to design a piece of genetic information capable of inserting itself into a mosquito’s genome. This construct was then injected into the eggs of the mosquitoes. The emerging generation carries the altered genetic information and passes it on to future generations. For their experiments, the scientists used Anopheles stephensi, a mosquito species that is an important malaria vector throughout the Indian subcontinent.

The researchers targeted one of the many biochemical pathways inside the mosquito’s cells. Specifically, they engineered a piece of genetic code acting as a molecular switch in the complex control of metabolic functions inside the cell. The genetic construct acts like a switch that is always set to “on,” leading to the permanent activity of a signaling enzyme called Akt. Akt functions as a messenger molecule in several metabolic functions, including larval development, immune response and lifespan.

When Riehle and his co-workers studied the genetically modified mosquitoes after feeding them malaria-infested blood, they noticed that the Plasmodium parasites did not infect a single study animal.

IMAGE: Under UV light, this mosquito larva reveals a red fluorescent marker in its nervous system, causing eyes and nerves to glow. The marker’s presence tells the researchers in Riehle’s…

Click here for more information.

“We were surprised how well this works,” said Riehle. “We were just hoping to see some effect on the mosquitoes’ growth rate, lifespan or their susceptibility to the parasite, but it was great to see that our construct blocked the infection process completely.”

Of the estimated 250 million people who contract malaria each year, 1 million – mostly children – do not survive. Ninety percent of the number of fatalities, which Riehle suspects to be underreported, occur in Sub-Saharan Africa.

Each new malaria case starts with a bite from a vector – a mosquito belonging to the genus Anopheles. About 25 species of Anopheles are significant vectors of the disease.

Only the female Anopheles mosquitoes feed on blood, which they need to produce eggs. When they bite an infected human or animal, they ingest the malaria parasite.

Once the Plasmodium cells find themselves in the insect’s midgut, they spring into action. They leave the insect’s digestive tract by squeezing through the midgut lining. The vast majority of Plasmodium cells do not survive this journey and are eliminated by the mosquito’s immune cells. A tiny fraction of parasite cells, usually not more than a handful, make it and attach themselves on the outside of the midgut wall where they develop into brooding cells called oocysts.

Within 10-12 days, thousands of new Plasmodium cells, so-called sporozoites, sprout inside the oocyst. After hatching from the oocyst, the sporozoites make their way into the insect’s salivary glands where they lie in wait until the mosquito finds a victim for a blood meal. When the mosquito bites, some sporozoites are flushed into the victim’s bloodstream.

“The average mosquito transmits about 40 sporozoites when it bites,” said Riehle, “but it takes only one to infect a human and make a new malaria victim.”

Several species of Plasmodium exist in different parts of the world, all of which are microscopically small single-celled organisms that live in their hosts’ red blood cells. Each time the parasites undergo a round of multiplication, their host cells burst and release the progeny into the bloodstream, causing the painful bouts of fever that malaria is known and feared for.

Malaria killed more soldiers in the Civil War than the fighting, according to Riehle. In fact, malaria was prevalent in most parts of the U.S. until the late 1940s and early 1950, when DDT spraying campaigns wiped the vectors off the map. Today, a new case of malaria occurs in the U.S. only on rare occasions.

The severity of the disease depends very largely on the species of the Plasmodium parasite the patient happens to contract.

“Only two species of Plasmodium cause the dreaded relapses of the disease,” said Riehle. “One of them, Plasmodium vivax, can lie dormant in the liver for 10 to 15 years, but now drugs have become available that target the parasites in the liver as well as those in the blood cells.”

That said, there are no effective or approved malaria vaccines. A few vaccine candidates have gone to clinical trials but they were shown to either be ineffective or provide only short-term protection. If an effective vaccine were to be developed, distribution would be a major problem, Riehle said.

Researchers and health officials put higher hopes into eradication programs, which aim at the disease-transmitting mosquitoes rather than the pathogens that cause it.

“The question is ‘What can we do to turn a good vector into a bad vector?'” Riehle said.

“The eradication scenario requires three things: A gene that disrupts the development of the parasite inside the mosquito, a genetic technique to bring that gene into the mosquito genome and a mechanism that gives the modified mosquito an edge over the natural populations so they can displace them over time.”

“The third requirement is going to be the most difficult of the three to realize,” he added, which is why his team decided to tackle the other two first.

“It was known that the Akt enzyme is involved in the mosquito’s growth rate and immune response, among other things,” Riehle said. “So we went ahead with this genetic construct to see if we can ramp up Akt function and help the insects’ immune system fight off the malaria parasite.”

The second rationale behind this approach was to use Akt signaling to stunt the mosquitoes’ growth and cut down on its lifespan.

“In the wild, a mosquito lives for an average of two weeks,” Riehle explained. “Only the oldest mosquitoes are able to transmit the parasite. If we can reduce the lifespan of the mosquitoes, we can reduce the number of infections.”

His research team discovered that mosquitoes carrying two copies of the altered gene had lost their ability to act as malaria vectors altogether.

“In that group of mosquitoes, not a single Plasmodium oocyst managed to form.”

At this point, the modified mosquitoes exist in a highly secured lab environment with no chance of escape. Once researchers find a way to replace wild mosquito populations with lab-bred ones, breakthroughs like the one achieved by Riehle’s group could pave the way toward a world in which malaria is all but history.

###

This study was funded by the National Institutes of Health.

Reference: Corby-Harris et al. Activation of Akt Signaling Reduces the Prevalence and Intensity of Malaria Parasite Infection and Lifespan in Anopheles stephensi Mosquitoes. Public Library of Science (PLoS) Pathogens, July 2010 issue: www.plospathogens.org

How do you like them genetic engineering guys now?


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