Although the introduction of bed nets treated with insecticide produced a measurable drop in malaria cases in Africa and reduced deaths from the disease by up to one million, the nets may provide little defense against a new species of mosquitos that carry malaria. The newly-discovered species targets people earlier in the evening, before they retire at night under the protection of bed nets.
New or Rare Species?
Researchers in Kenya and Benin collected hundreds of mosquitos in outdoor and indoor traps, and just under half of the specimens belonged to the new type. Questions arose as to whether the mosquitos are truly an entirely new species or a new form of an already-identified species. The emergence of the questionable mosquitos may actually be due to recent successes in malaria control. Known mosquito species have been suppressed by the disease control measures, possibly making way for new species to emerge more prevalently. The threat posed by the new mosquitos is still unclear, and researchers are studying the species’ ability to transmit the parasite that causes malaria to humans.
Changing Mosquito Behavior
The introduction of bed nets has also altered the behavior of know mosquito species. In Benin, malaria-carrying species of mosquitos became more active later in the night after bed nets were introduced to the region. Mosquitos that previously were most active from 2 am to 3 am became most active at 5 am, targeting farmers who rise early.