By North Forty News Staff | NorthFortyNews.com
New study ranks Colorado 46th for mosquito activity, but local surveillance and spraying programs remain active to reduce West Nile virus risk.
LOVELAND, Colo. — Colorado may be one of the least mosquito-prone states in the nation, but Northern Colorado communities are still taking steps to prevent the spread of West Nile virus as summer mosquito season gets underway.
A new analysis by equine nutrition company Mad Barn ranked Colorado 46th out of 48 contiguous states for mosquito activity, citing the state’s dry climate, relatively low humidity, and limited summer rainfall. Despite those favorable conditions, the City of Loveland has launched its annual mosquito surveillance and control program to help reduce the risk of mosquito-borne illness.
The city and its mosquito management contractor, Vector Disease Control International (VDCI), will monitor mosquito populations through September using 40 trap locations across Loveland. Mosquitoes collected from the traps are tested for West Nile virus, and targeted spraying may occur when mosquito populations exceed established thresholds.
According to the study, Colorado receives an average of just 1.8 inches of summer rainfall and maintains humidity levels of approximately 49%, among the lowest in the country. Those conditions reduce standing water and make it more difficult for mosquitoes to establish large populations.
Only Wyoming and Nevada ranked lower than Colorado in overall mosquito prevalence.
By comparison, Florida, Louisiana, and Texas topped the rankings due to combinations of high humidity, abundant rainfall, warm temperatures, and large numbers of mosquito species.
While Colorado’s climate naturally limits mosquito populations, public health officials caution that West Nile virus remains a seasonal concern. Even relatively small mosquito populations can carry the virus, particularly Culex mosquitoes, the primary vectors responsible for human transmission.
Loveland’s mosquito management efforts include:
- Monitoring mosquito populations throughout the city
- Testing mosquitoes for West Nile virus
- Applying larvicide treatments to breeding areas
- Conducting targeted fog-spraying when mosquito counts or virus activity reach action levels
Residents can track mosquito activity, testing results, and spray zones through VDCI’s online monitoring system. Spray notifications and shut-off requests are also available for residents who wish to receive advance notice before spraying occurs.
Health officials continue to encourage residents to follow the “Four Ds” of mosquito prevention:
- DEET: Use EPA-approved mosquito repellents.
- Dusk to Dawn: Limit outdoor exposure during peak mosquito feeding times.
- Dress: Wear long sleeves and pants when outdoors.
- Drain: Eliminate standing water around homes and yards.
Almost any standing water that remains for more than five days can become a mosquito breeding site.
Mosquito control services in Loveland are funded through the city’s Mosquito Control Enterprise Fund, which is supported by a fee included on utility bills.
Source: City of Loveland; Mad Barn mosquito prevalence study using National Centers for Environmental Information data.
One of the challenges of local journalism is balancing perspective with preparedness. Colorado’s dry climate helps keep mosquito populations lower than most states, but West Nile virus remains a real concern every summer in Northern Colorado. The Daily Update helps connect national and statewide trends to what’s happening right here in our communities each morning.
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