The West Sacramento area in California is evaluating a potential threat of West Nile Virus.  Many dead birds have been found and 18 have tested positive for West Nile Virus.  Additionally, 58 mosquito tests have also been positive for the disease.  Though more intense in Sacramento County, West Nile Virus is also presenting in other areas.  Yolo County has had six dead birds and 19 mosquito samples that were infected.  There has been one human case that has been confirmed by the California Department of Public Health.

Officials are considering aerial spraying to kill mosquitoes and prevent the further spread of the virus.  West Nile Virus and mosquito management are an annual issue since the disease was first found in California 10 years ago.  Aerial spraying is always controversial due to concerns about public health.

In the May-June 2013 issue of the journal Public Health Reports, researchers published a study analyzing the correlation between aerial spraying of insecticides and short-term health effects.  Examining the time period after aerial spraying in Sacramento County in August 2005, the researchers looked for clusters of medical complaints, such as respiratory illness, skin or eye conditions, gastrointestinal issues, and neurological complaints.  The study found no significant correlations or clusters for these medical complaints.

West Nile Virus is a mosquito-borne illness that can be spread to humans.  Reducing the risk of being bit by a mosquito reduces the risk for contracting the disease.  Twenty percent of individuals that are infected by the virus develop West Nile fever, which shows mild symptoms similar to a fever or common infection.  A less likely development is West Nile encephalitis, which is more severe, including symptoms such as tremors, high fever, paralysis, and coma.

According to the Centers for Disease Control and Prevention, other illnesses transmitted by mosquitoes include dengue fever, malaria, yellow fever, and several diseases that cause encephalitis.  Controlling the mosquito population, particularly in areas that have a higher risk or incidence of one of these diseases, helps reduce the spread of disease.  Aerial spraying is one means for controlling the mosquito population.  In addition to those opposed for public health concerns, some do not think aerial spraying is effective.  Another option is misting, which reportedly uses fewer pesticides, is easier to control drift of pesticides in the air, can be better targeted to areas where mosquitoes live, and can disrupt the breeding cycle for a long-term solution to mosquito problems.