The Centers for Disease Control and Prevention (CDC) said yesterday (May 1st) that there’s been a surge in the U.S. in illnesses caused by infected mosquitoes, ticks and fleas, with the number tripling from 2004 to 2016. The largest increase was fueled by the emergence of the moquito-borne Zika virus from 2015 to 2016, but there has also been a steady increase in cases of tick-borne Lyme disease.

The report additionally identified seven new germs carried by ticks that have been discovered since 2004. Amid these increases, the CDC said 80 percent of the vector control organizations meant to control these infections aren’t equipped to do so. The CDC’s Lyle Petersen told Reuters that climate change may be to blame for the increases, saying that the shorter winters and rising summer temperatures can boost the insect population, as well as outbreaks of illnesses they carry.