Wednesday, July 17, 2013

What Caused Dallas County’s 2012 West Nile Virus Outbreak?

West Nile virus in Dallas County reached epidemic proportions last summer. The virus, which is transmitted to humans through mosquitoes that bite infected birds, severely sickened more than 400 and killed 19. A study by the Journal of the American Medical Association (JAMA) identified several factors behind the worst West Nile virus outbreak in Texas history, and provides valuable information for preventing future outbreaks.

The winter of 2011 was unusually warm, and the spring of 2012 was unusually wet, reported JAMA. As a result, large numbers of virus-carrying mosquitoes managed to survive through the winter and thrive during the spring. Additionally, the economic downturn meant houses in affluent neighborhoods remained unsold, and abandoned backyard swimming pools became mosquito breeding grounds. By late June, 5 percent of the mosquitoes in Dallas County carried West Nile virus, though no one knew it.

The JAMA report also cites the county’s delayed response to controlling the mosquito population through aerial spraying as another reason the virus was able to infect so many people. Had officials reacted sooner to approve aerial spraying in early July instead of late July, hundreds of severe infections and several deaths could have been prevented, the study surmised.

Texas lawmakers passed a law this session that allows local officials in Dallas to enter abandoned residential property to remove stagnant water to prevent future outbreaks. The legislation, Senate Bill 186, was authored by Sen. John Carona (R-Dallas).

No comments :

Post a Comment

Related Posts Plugin for WordPress, Blogger...