HUNTINGTON — Break out the bug spray and grab a long-sleeved shirt — the time is near for some of the baddest pests to make their seasonal return.
According to the National Pest Management Association’s recently released biannual “Bug Barometer” forecast, those in the Ohio Valley and most of the country can expect an increase in tick and mosquito populations.
“While regions across the country were either unseasonably cold or warm this past winter, there’s one factor that almost all of them had in common — excessive moisture,” said Jim Fredericks, chief entomologist for the NPMA.
According to the group’s team of entomologists, residual winter moisture coupled with wet spring forecasts will cause pest populations to spike early in much of the country this spring and summer.
“Continued precipitation predicted for most of the country this upcoming season will allow pest populations to continue to thrive and multiply,” Fredericks added.
Jim Joy, professor of biological sciences at Marshall University, says rainfall may not be the only factor in pest activity.
“The Asian tiger mosquito, for example, does not tolerate our winters very well, and thus populations of this species tend to lag behind other mosquito species,” he explained. “Eventually, the Asian tiger mosquito does reach high population levels later in the summer, in at least one past year becoming the dominant Aedes species along the Ohio River in August and September. At least that is what I’ve observed.”
Joy says the MU Medical Entomology Lab was the first to report the (invasive) Asian Tiger mosquito in the state.
Eric Dotseth, a public health entomologist with the Division of Infectious Disease Epidemiology in the Office of Epidemiology Prevention Services within the West Virginia Department of Health and Human Resources, says the increased precipitation would increase the populations of disease-carrying (pestiferous) mosquitoes.
“We have seen increases in adult wetland pestiferous mosquitoes, including the inland floodwater mosquito, plains floodwater mosquito, woodland mosquito, gallinipper mosquitoes, Psorophora columbiae and Psorophora horrida, during periods of prolonged rain,” Dotseth said.
“These mosquitoes spend the winter as eggs in moist soil, either near small bodies of water or areas prone to accumulating water. These eggs hatch when submerged under water following rain events. Although these mosquito species can increase dramatically in numbers and will readily feed on human hosts, these pestiferous mosquitoes are not effective vectors for human diseases,” Dotseth said.
He said that the wet spring forecast could also activate overwintering eggs of container-breeding mosquitoes.
“Many of our La Crosse encephalitis competent vectors, including the eastern treehole mosquito, Asian rock pool mosquito and Asian tiger mosquito, lay their eggs along the interior edges of artificial containers, like tires, buckets, barrels and children’s wading pools, as well as natural containers, like tree holes. These eggs also hatch when submerged under water following rain events,” he said.
Another concern, according to Dotseth, is blacklegged ticks, often referred to as deer ticks.
“Moisture is conducive to blacklegged ticks, tick vector for Lyme disease, human anaplasmosis, human babesiosis and Powassan encephalitis,” he said.
The influence of different weather events on pre-existing vector populations — insects that are carriers — in different habitats over time is more difficult to predict.
“The West Virginia Department of Health and Human Resources’ state and local health departments conduct mosquito and tick surveillance across the state to both monitor vector populations and human pathogen activity in these mosquito and tick populations,” Dotseth said.
Annual zoonotic (spread between animals and people) disease reports and regular seasonal summaries about vector-borne disease activity are available at https://oeps.wv.gov/arboviral/pages/ default.aspx#data.
“People should remain diligent about protection against mosquito and tick-borne disease,” Dotseth said. “Recommendations include insect and tick repellent, removal of artificial containers conducive to larval mosquito development, tick prevention for pets and body checks for ticks.”
As far as nuisance insects are concerned, Dotseth said he did not have any insights on predicted stink bug activity for the upcoming spring and summer. However, according to the NPMA’s Bug Barometer, cockroach, ant and fly populations in drier regions will push their way indoors in search of food and water. The group’s seasonal forecast for the Ohio Valley region warns that drier summer conditions could also drive earwigs and springtails indoors in search of water.
“This could bring about a whole host of indoor pest-related health issues including food contamination. Cockroaches can also trigger asthma and allergy symptoms,” Fredericks said.
For more information on NPMA’s Bug Barometer or to learn more about protecting against common household pests, visit PestWorld.org.