Warm Weather and Drought May Lead to Abundance of Mosquitoes

West Nile Virus and Mosquito and Vector Control Awareness Week educates California residents on preventing viruses transmitted by mosquitoes

SACRAMENTO, APRIL 17, 2015 – With California’s unusually warm weather and the driest year in the state’s history, Californians may see an unprecedented number of mosquito transmitted diseases in 2015.

To raise awareness and educate Californians about the public health threats mosquitoes and vectors can have on our local communities, the California Legislature declared April 19 – 25, 2015 as West Nile Virus and Mosquito and Vector Control Awareness Week in California.

With 2015 marking the 100-year anniversary of California’s Mosquito Abatement Districts Act (AB 1590 enacted in 1915), local mosquito and vector control agencies need to be more diligent than ever. California experienced record-breaking West Nile virus (WNV) activity in 2014 and several exotic mosquito species capable of transmitting deadly diseases have been discovered in the last couple of years and are now permanently established in some California communities.

The California Department of Public Health (CDPH) reported 801 human cases of WNV, 561 of which were the serious neurological form of the disease, and 31 deaths, the highest number of fatalities in California since the disease was first detected in 2003. A contributing factor for the staggering number of WNV cases could be a result of the ongoing drought, which reduced the number of sources of water for birds and mosquitoes.

Invasive species capable of transmitting a number of life-threatening diseases including chikungunya, dengue, and yellow fever, are posing an increasing threat to Californians. While these diseases have not been transmitted locally in California at this point, efforts to control these mosquitoes are adding increasing challenges to vector control agencies statewide.

Predicting the level of WNV in any given year is not possible as WNV activity depends on a number of factors including climate, number and species of birds and mosquitoes in an area, as well as the level of immunity in birds to WNV. However, if California continues to experience warm temperatures, we can count on an early start to mosquito and WNV season, extending the number of months local communities and residents are at risk of contracting potential deadly diseases transmitted by mosquitoes.

“It is critical that public agencies do their job to protect nearly 38 million Californians that are at risk and exposed to mosquitoes on a nearly daily basis. Education is key to protection and prevention,” said Joel Buettner, President of the Mosquito and Vector Control Association of California (MVCAC). “It is our job to increase awareness about the severe public health threats mosquitoes pose to our state and residents. Equally as important is communicating prevention methods that can be employed to protect yourself and your local communities,” added Buettner.

To minimize exposure to mosquito bites and WNV, practice the “3 Ds:”

  1. DEET – Apply insect repellent containing DEET, picaradin, oil of lemon eucalyptus, or IR3535 according to label instructions. Repellents keep mosquitoes from biting. DEET can be used safely on infants and children 2 months of age and older.
  2. DAWN AND DUSK – Mosquitoes capable of transmitting WNV are most active in the early morning and evening, so it important to wear protective clothing and repellent if you are outside during these times. Make sure that your doors and windows have tight-fitting screens to keep out mosquitoes. Repair or replace screens with tears or holes.
  3. DRAIN – Mosquitoes lay their eggs on standing water. Eliminate all sources of standing water on your property, including in flower pots, old car tires and buckets. If you know of a swimming pool that is not being properly maintained, please contact your local mosquito and vector control agency.

To increase awareness and enforce prevention and control programs statewide, the MVCAC provides support to more than 65 districts throughout California. As a result, approximately half the land area and 85 percent of California’s population are within the boundaries of a mosquito control program.

MVCAC represents special districts, other subdivisions of local government, and the state of California which are responsible for mosquito and vector control, surveillance of WNV and other vector-borne diseases, as well as public education programs to help Californians protect themselves from disease. MVCAC advocates safe, effective, and environmentally friendly methods of mosquito and vector control.

The MVCAC will be participating in a public education effort, “Fight the Bite 2015,” at the State Capitol on Thursday, April 23rd from 9:30 am – 1:00 pm.