Female Aedes aegypti mosquito as she was in the process of obtaining a “blood meal.” (credit: US Department of Health and Human Services)
The Centers for Disease Control and Prevention released an alarming report yesterday, declaring that cases of diseases spread by ticks, mosquitos, and fleas more than tripled in the US between 2004 and 2016. Unnerving headlines followed, emphasizing the tripling (e.g. The Washington Post) or some making claims that tick and mosquito infections are “spreading rapidly” (e.g. The New York Times).
But a look at the data tells a more nuanced, less alarming story.
The CDC’s data, published in the agency’s Morbidity and Mortality Weekly Report, clumps together cases of 16 different types of diseases spread by insects (called “vector-borne diseases”), which are each reported to the National Notifiable Disease Surveillance System (NNDSS). This system covers all US states as well as US territories. The agency noted in its press materials that this is the first time they’ve ever aggregated disease counts together like this for one analysis. (Why they chose to start this year is anyone’s guess. Perhaps because it allowed them to say things like “diseases tripled.” Who knows?)
Source: FS – All – Science – News
Why you shouldn’t freak out about CDC’s insect-spread disease counts tripling