More than 180 nations signed the Persistent Organic Pollutants Treaty (POPs), often called the Stockholm Convention. The treaty pledges nations to voluntarily work to rid the planet of dangerous and toxic organic chemicals.
DDT is named in negotiation documents as one of the Dirty Dozen most toxic pollutants; however, because there was no alternative that performed exactly like DDT, the nations made a special addendum to the treaty to allow any nation to use DDT to fight disease vectors (insects that carry disease). The World Health Organization tracks use of DDT.
In 2001, 43 nations said they thought DDT would be useful. But by 2015, 33 of those nations gave up DDT, due to insects developing resistance and immunity.
India, the sole remaining nation where manufacture of DDT occurs, plans to stop all DDT production by 2020. India discovered that more DDT makes the insect pests more resistant faster, instead of beating disease carriers.
This map from the UN Environmental Program shows declining use of DDT, 2000 to 2014. ][If that link doesn’t work, and it’s been iffy, try this one for information: https://www.unenvironment.org/explore-topics/chemicals-waste/what-we-do/persistent-organic-pollutants/alternatives-ddt]