Culicidae

Mosquito coil is a vector control option used to prevent malaria in low income counties, while some studies have addressed this issue, additional reseach is required to increase knowledge on the adverse health effects caused by the prolonged use of coils. In this study we investigated the toxicological effects of fumes from two locally manufactured mosquito coil insecticides (with pyrethroids: transfluthrin and d-allethrin as active ingredients) on male albino rats. For this, we recorded the haematological and biochemical indices, and made histopathology and mutagenicity evaluations in rats exposed to mosquito fumes during 2, 4, 8, 12 and 16 week periods. Haematological determination was performed using automated hematology analyzer to determine White Blood Cell (WBC), Packed Cell Volume (PCV), Red Blood Cell (RBC) and Platelet (PLT) counts, while biochemical evaluations were determined using available commercial kits. Gross histopathological changes were studied for the kidney, liv...

Temperature is one of the most important factors affecting
the life of insects. For instance, high temperatures can
have deleterious effects on insects’ physiology. Therefore,
many of them have developed various strategies to avoid
the risk of thermal stress. They can seek a fresher environment
or adjust their water loss, but hematophagous
insects, such as mosquitoes, must confront the issue of
thermal stress at each feeding event on a warm-blooded
host. To better understand to what extent mosquitoes
are exposed to thermal stress while feeding, we conducted
a real-time infrared thermographic analysis of mosquitoes’
body temperature during feeding on both warm blood and
sugar solution. First, our results highlighted differences in
temperature between the body parts of the mosquito (i.e.,
heterothermy) during blood intake, but not during sugar
meals. We also found that anopheline mosquitoes can
decrease their body temperature during blood feeding
thanks to evaporative cooling of fluid droplets, which are
excreted and maintained at the end of the abdomen. This
mechanism protects the insect itself, probably as well as
the sheltered microorganisms, both symbionts and parasites,
from thermal stress. These findings constitute the first
evidence of thermoregulation among hematophagous
insects and explain the paradox of fresh blood excretion
during feeding