West Nile, dengue and other arbovirus patterns are changing with the climate

Mosquito activity is beginning earlier and extending later, while population distribution increases

Experts have raised the alarm that climate change is reshaping the landscape of mosquito activity, leading to significant public and global health concerns.

Warmer temperatures and changing precipitation patterns are not only causing mosquito populations to grow; these changes are also driving an expansion of mosquitos into new regions and to remain active for longer periods each year. Extended mosquito seasons increase the risk of the spread of arboviruses-dangerous mosquito-transmitted viruses, such as Zika, West Nile, eastern equine encephalitis (EEE), dengue fever and malaria.

As these insects move into areas that had earlier been too cool for their survival, they bring with them the potential for outbreaks of diseases in regions that had previously been unaffected. Effective mosquito abatement and mitigation strategies, such as the use of real-time PCR technology solutions, are now more critical than ever.

Without prompt and comprehensive action, the health impacts of expanding mosquito populations could become increasingly severe.

Past, Present and Future

The world has changed considerably since 1886 when Cuban physician Carlos Finlay first suggested the Aedes aegypti mosquito might be a carrier for yellow fever, later confirmed by Major Walter Reed in 1900, what was shortly after Sir Ronald Ross discovered the Anopheles mosquito carried the malaria parasite in 1897. Prior to these discoveries, outbreaks of arboviruses like yellow fever regularly impacted global health and could easily kill thousands in a localized area over a short period of time.

While helpful in slowing the spread of arboviruses in tropical and subtropical regions, effective mosquito mitigation in the early 20^th century had an even more dramatic and immediate effect in more temperate climates, such as North America and Europe.

However, in recent decades changing climate patterns have been accompanied by an expansion of the world's deadliest animal-the mosquito, responsible for nearly a million deaths every year according to the CDC.

Mosquitos carrying arboviruses like dengue and malaria act as disease vectors that are now able to populate more regions, as temperatures warm year-over-year and as changing rainfall patterns continue to cause droughts followed by floods.

Incidences of illnesses like West Nile and eastern equine encephalitis (EEE) are on the rise as far north as New England, where cities issued voluntary lockdowns to prevent the spread of EEE during the hours when mosquitos are most active.

As of July 10, 2024 the number of dengue cases reported in the United States was roughly five times higher than 2023. The Pan American Health Organization (PAHO) reported on August 22, 2024 that the cumulative incidence of dengue so far this year has increased by 233% compared to the same period in 2023, and 416% compared to the average of the last 5 years.

A 2021 study in The Lancet predicts that as many as 4.7 billion people could be at risk of malaria and dengue if climate change remains on the current trajectory.

Co-Dx provides modern PCR mosquito abatement solutions to age-old global health problems

Traditional mosquito abatement and mitigation strategies, such as treating standing bodies of water for mosquito larvae and insecticide spraying during the hours when mosquitos are most active, must be complemented with innovative approaches-including cutting-edge surveillance systems-to keep these growing threats in check.

The intersection of climate change and mosquito-borne diseases underscores the urgency of mosquito abatement districts, or MADs, to adopt the best and most modern technologies to protect public and global health, including in-house polymerase chain reaction (PCR) to monitor and track mosquito pools carrying arboviruses.

Co-Dx Vector Control solutions can empower MADs to identify where mosquito pools might be harboring some of these dangerous-and deadly-viruses. Same-day real-time PCR test results can allow MADs to avoid waiting days for results from mosquito pool testing and to focus their mitigation efforts immediately, more efficiently and effectively.

High quality in-house tools by Co-Dx help MADs to keep our communities safe, in real-time. And in the race to stay ahead of a changing climate, time matters.