Mosquito sterilization offers new opportunity to control dengue, Zika and chikungunya
A technique that produces sterilized male mosquitoes using radiation will soon be tested as part of global health efforts to control diseases such as dengue, Zika or chikungunya.
The Sterile Insect Technique (SIT) is a form of insect birth control by mass rearing in dedicated facilities of sterilized male mosquitos, which are then released to mate with females in the wild. As these do not produce any offspring, the insect population declines over time.
TDR (the Special Programme for Research and Training in Tropical Diseases), the International Atomic Energy Agency (IAEA), in partnership with the Food and Agriculture Organization of the United Nations (FAO), and the World Health Organization have developed a guidance document for countries interested in testing the Sterile Insect Technique (SIT) for Aedes mosquitoes.
“Half the world’s population is now at risk of dengue,” said Dr Soumya Swaminathan, WHO Chief Scientist. “And despite our best efforts, current efforts to control it are falling short. We desperately need new approaches and this initiative is both promising and exciting.”
In recent decades, the incidence of dengue has increased dramatically due to environmental changes, unregulated urbanization, transport and travel, and insufficient sustainable vector control tools and their application.
Dengue outbreaks are currently occurring in several countries, notably on the Indian sub-continent. Bangladesh is facing the worst outbreak of dengue since its first recorded epidemic in 2000. The South Asian nation has seen the number of cases rise to over 92,000 since January 2019, with the daily admission peaking to over 1,500 new dengue patients in hospitals in recent weeks.
Diseases transmitted by mosquitoes such as malaria, dengue, Zika, chikungunya, and yellow fever account for about 17% of all infectious diseases globally, claiming more than 700,000 lives each year, and inflicting suffering on many more. The 2015 outbreak of Zika in Brazil was linked to an increase in the number of babies being born with microcephaly.
SIT was first developed by the U.S. Department of Agriculture and has been used successfully to target insect pests that attack crops and livestock, such as the Mediterranean fruit fly and the New World screwworm fly. It is currently in use globally in the agriculture sector on six continents. The technique will now be applied to control diseases in humans transmitted by Aedes mosquitoes, including dengue, Zika, and chikungunya.
The guidance includes, among others, a phased approach to test the efficacy of the sterilized insects through epidemiological indicators to assess the impact of the method on disease-transmission.
“Countries seriously affected by dengue and Zika have shown real interest in testing this technology as it can help suppress mosquitoes that are developing resistance to insecticides, which are also negatively impacting the environment,” said Florence Fouque, a scientist at TDR.
The collaborative effort includes plans to support three multi-country teams of research institutions, vector control agencies and public health stakeholders to test SIT against Aedes mosquitoes.
“The use of SIT in the agriculture sector in the past 60 years has shown that it is a safe and effective method,” said Jérémy Bouyer, medical entomologist at the Joint FAO/IAEA Division of Nuclear Techniques in Food and Agriculture. “We are excited to collaborate with TDR and WHO to bring this technology to the health sector to fight human diseases.”
PRESS RELEASE 14 November 2019 WHO TDR
Vacancy announcement for Project Officer- Medic Mobile
5th GCP Regional Training, Kathmandu, 16-18th December, 2019
Call for application! 5th Implementation Research (IR) Regional Training, Kathmandu
