Challenges and options for disease vector control

Abstract

The ongoing Zika virus outbreak, which briefly threatened to put a stop to the 2016 Olympic Games in Brazil, has again focused attention on the threat of vector‐borne diseases. One efficient strategy to battle such diseases, now underway in Brazil to fight the Zika virus, is to kill the insects that carry the pathogen. Vector control has been practised with varying effectiveness for at least half a century, especially for malaria; the Brazil outbreak again highlights the need for integrating existing methods including the use of insecticides, vaccines, drugs and low technology such as sanitation to keep insect vectors at bay. In addition, new approaches are being developed based on sophisticated methods such as genome editing of the insect vector and deliberate infection of mosquitoes with the Wolbachia bacteria. However, attempts to scale up these new methods from field trials to deployment have been slowed down or halted by environmental concerns or public resistance against genetically modified organisms. The Zika outbreak in South America has stimulated cross‐border collaboration of public health authorities and increased pressure to use new integrative approaches that are essential for combatting vector‐borne diseases. The irony is that the Zika virus itself has a minimal global impact compared with other insect‐borne pathogens, but it has attracted enormous publicity because of the risk of causing microcephaly in unborn children, combined with the coincidence of the outbreak during the Olympic year. The exact risk for the foetus is as yet unknown [1], but it is clear that Zika is otherwise a relatively mild disease with no symptoms in the majority of cases (http://www.cdc.gov/zika/symptoms/index.html). By contrast, other mosquito‐borne diseases, including malaria, yellow fever, dengue and chikungunya (CHIKV), are major causes of both mortality and morbidity, responsible for hundreds of millions of cases each year and millions of deaths …