InSectIcideS used for vector control and health in the context of HIV – A long-term mother-child cohort in Mozambique – ISIS

Malaria is highly prevalent in many countries in sub-Saharan Africa (SSA) leading to a huge burden in terms to childhood mortality and morbidity. The estimated number of malaria deaths was at 619 000 in 2021. Insecticides are largely used for vector control, including indoor residual praying (IRS). These insecticides are designed to target nervous system for eliminating insects. Many of them are suspected to affect child neurodevelopment, to be endocrine disruptors, to be highly persistent in the environment, and to alter biodiversity. Dichlorodiphenyltrichloroethane (DDT) has been banned in most industrialized countries because of its long-term persistence in the environment, but it is still used for control of vector-borne diseases in SSA. Mosquitoes are however more and more resistant to several insecticides, leading to frequent changes in the types of insecticides used. Insecticides used in malaria-endemic areas include DDT, pyrethroids, organophosphates, neonicotinoid, and carbamates.
Despite this extensive use, many questions are unanswered. 1/ There is little literature on the extent to which vulnerable populations are exposed to these insecticides used for vector control. 2/ Little is known on health consequences of these exposures on health of pregnant women and children.

The overall objective of our project is to study health consequences of exposure to insecticides used for vector control in pregnancy and in adolescents in the context of high prevalence of HIV.
Pre and post-natal DDT, as well as other insecticides used, will be studied. Offspring health in adolescence includes cognitive function and behavior, mental health, cardiometabolic health, thyroid function, puberty, allergies and asthma.

Building on our existing mother-child cohort in Mozambique, participants include 550 dyads of women and offspring at 13-14 years of age. 250 offspring born to HIV positive pregnant women and 300 born to HIV negative pregnant women.