Medicine

Tick, mosquito infections spreading rapidly, CDC finds

Tick, mosquito infections spreading rapidly, CDC finds

That's enough to help nine states to increase their ability to manage vector-borne disease, Petersen said.

- The Centers for Disease Control and Prevention reported Tuesday that disease cases from mosquito, tick and flea bites tripled in the USA from 2004 to 2016.

The CDC said local public health departments need to do more to control mosquito, tick and flea populations.

The responsibility for detecting and responding to diseases spread by vectors such as mosquitoes and ticks is nearly all funded locally and operated by local and state health departments.

And although it's rare, plague is still transmitted by fleas.

Mosquito-borne infections are most likely to hit sunnier states and territories.

While the increase in tick-borne illnesses was gradual, rising steadily each year, the increase in mosquito-borne diseases was more sudden, driven by recent epidemics of West Nile virus and Zika virus.

Tick-borne diseases are mainly found in the eastern continental United States and areas along the Pacific coast, the researchers said. Longer, hotter summers are not helping, said Dr. Lyle Petersen of the CDC's National Center for Emerging and Zoonotic Infectious Diseases. "They are spread by movements of people or animals or vectors, and with expanding global travel and trade, all diseases are basically a plane flight away", he said.

"Amblyomma spp, which is a voracious feeder, has also been identified in the Northeast, where it was usually just in the southern U.S. Depending on where you are in the country, ticks may emerge at a time when most folks aren't aware of them, easily the result of shifts in phenology due to climate change". Lyme disease is the most common tick-borne illness, and the CDC researchers found the area where Lyme disease exposure is a risk has been growing in recent years.

Of the 642,602 total reported cases, more than 75 percent were caused by tick-borne diseases - most commonly, Lyme disease.




"Why the increase? Mosquitoes and ticks are moving into new areas nationwide", Robert Redfield, MD, director of the CDC said in a media telebriefing.

"The number of reported vector-borne disease cases has tripled over the last 13 years", Petersen told reporters in a telephone briefing.

During this time period, nine new germs spread by mosquitoes and ticks were either discovered or introduced into the U.S.

Also, Lyme disease accounted for 82% of tick-borne diseases during this time period, they wrote in "Vital Signs", in the Morbidity and Mortality Weekly Report.

As temperatures rise, ticks that carry infections can spread further north and can remain infectious longer into fall and winter, Petersen said.

"Zika funding helped prepare us for these types of diseases, but more funding is necessary", he said.

Agencies can also train vector control staff on core competencies for conducting prevention and control activities.

Paul Auwaerter, MD, president of the Infectious Diseases Society of America, said vector-borne diseases "can devastate patients and their families, causing significant suffering", and that the IDSA urges Congress to increase funding for surveillance and prevention efforts, including resources to support finding the best prevention methods.

Residents can also learn how to prevent bites and control germs spread by mosquitoes, ticks and fleas in their communities, including the use of insect repellent.