Under the heat wave, the disease-resistant mosquitoes can't carry it? Studies say it can also resist for a while

The number of days in each year

Affected population (number)

Annual dynamics of disease-resistant mosquito populations. Different color lines correspond to different age temperature states, historically yellow, orange in the 2030s, and red in the 2050s, which shows that the affected population is gradually increasing.

Image source: Nature Climate Change

Science and Technology Daily Beijing, August 8 (Reporter Zhang Mengran) The latest modelling study published in Nature Climate Change shows that the wMel strain of Wolbachia bacteria, which blocks the transmission of mosquito-borne viruses such as dengue virus, may still be effective in predicted heat wave scenarios through the 7s. However, its effect in longer-term warming scenarios is uncertain.

Mosquito-borne diseases, including malaria, dengue and Zika virus infection, affect millions of people and may pose greater risks in future climatic conditions as temperatures affect the geographical distribution and prevalence of these diseases.

One promising biocontrol technology is to replace wild mosquitoes with mosquitoes that carry a specific bacterium that blocks the infection and transmission of various mosquito-borne disease pathogens. Now, multiple strains of Wolbachia bacteria have been introduced into different Aedes mosquito species and tested in Latin America, Asia and Oceania, most of which use the wMel strain. However, there are concerns that the effectiveness of the wMel strain may diminish under heat stress.

The UC Berkeley team used data on the impact of laboratory temperature on wMel and prediction of future heat wave severity to establish a mosquito population dynamics model and selected two urban environments for experiments. Studies have shown that the technology is also resilient to projected near-term (2030s) climate change. But the study also reveals the potential vulnerability of wMel technology to high temperature variability and longer-term climate change.

The team expects that heatwaves in the 2050s may last longer (2030 days on average) than those in the 9s (7.24 days on average), which can have a serious negative impact on wMel, so more adaptive approaches to mosquito-borne diseases are still needed.