**Mosquito Ranges Expand, Bringing New Disease Risks**
With summer heat comes the inevitable swarms of bloodthirsty mosquitoes. However, their species are changing in historically temperate regions like New England. As climate change makes these areas warmer and wetter, their ranges are expanding—and any diseases they carry come with them.
In Connecticut, for example, a statewide mosquito monitoring program has detected 54 different species, including invasives like the Asian tiger mosquito, which can transmit potentially serious diseases including dengue and Zika. The mosquito’s historical territory is in hot and humid climates farther south, but it has been moving north.
“There are a number of new species that are creeping into our area,” said Philip Armstrong, chief scientist at the Connecticut Agricultural Experiment Station, which coordinates the state’s mosquito trapping and testing program. “You really do have to test the mosquitoes to know where the hot spots are for these viruses.” By the time human cases are reported, it’s usually too late to take action.
**A Patchwork System of Monitoring**
There aren’t statewide monitoring programs in much of the country. Instead, a patchwork quilt of more than 1,000 mosquito control agencies tries to keep ahead of an evolving problem. Most are run at the local level, with varying organizational structures and monitoring practices.
The US ought to have a national surveillance database collecting and sharing information from all monitoring programs, said Dan Markowski of the American Mosquito Control Association, a nonprofit that works to reduce mosquitoes and vector-transmitted diseases. But, he added, “it all obviously comes back to money.”
**Climate Change Alters Disease Risks**
In temperate regions like the Northeast, global warming can alter mosquito-borne disease risks not only by expanding the range of virus-carrying insects but also by lengthening the transmission season, reducing the number of mosquito predators and changing habitats. Researchers predict that tropical mosquito-borne diseases like Zika, dengue, chikungunya, and malaria will likely become established in temperate areas because of climate change.
“As the temperatures rise, you can actually speed up mosquito development, so you can have multiple cycles of mosquitoes every year in new areas,” said Brian Leydet, who studies mosquito- and tick-borne diseases at the State University of New York College of Environmental Science and Forestry. Beyond mosquitoes, Leydet said environmental changes can also affect viruses and their original hosts, such as birds and deer, creating complex ecological shifts that can be difficult to study.
**Funding Challenges**
Monitoring programs are typically labor-intensive and expensive, requiring teams to set and check traps, alongside specialists who can identify, sort, and test the samples. While some traps attract female mosquitoes with “stinky water” loaded with decaying organic material, others require dry ice to release carbon dioxide that mosquitoes sniff out when hunting for mammals.
But in rural parts of New York, dry ice can be hard to come by—the team had to make their own. Even beyond the logistical and resource challenges, communication, coordination, and data sharing for mosquito monitoring can be a challenge. “One of the problems with states that are not comprehensively doing these surveillance programs is that surveillance is hit or miss,” Leydet said.
**A Call for Comprehensive Surveillance**
That could change with a bill introduced in the New York State Legislature this session, which would lay the groundwork for a comprehensive mosquito surveillance program—rather than what the bill calls the “sparse and disintegrated” current system—to help public health officials respond before an outbreak.
Source: Original article