Spring rains bring a decent amount of moisture to Oklahoma, creating favorable breeding conditions for mosquitoes, said Justin Talley, Oklahoma State University Extension livestock entomologist. 
  
“The size and intensity of the mosquito population from year to year is dictated by the amount of moisture in the environment,” he said. “In a year with fairly mild temperatures, we usually have a pretty significant mosquito population as long as the moisture stays around. We mainly need to be concerned about mosquitoes from late spring all the way through early fall.” 
  
Flood water mosquitoes come with significant rainfall amounts but present no real concerns about disease transmission. However, species of both container breeding and transient water mosquitoes are related to multiple viruses that are potentially troublesome for humans. 
  
Though usually associated with urban or suburban environments, container breeding mosquitoes can be found anywhere water pools for an extended period of time in a confined area such as a bird bath or tree hole. 
  
“Any container that can hold water for at least 10 to 20 days can harbor container breeding mosquitoes, which are linked to dengue, chikungunya and Zika viruses,” Talley said. 
  
Meanwhile, transient water mosquitoes such as those that belong in the Culex genus, the main culprit behind West Nile virus, typically require warmer temperatures and become more prevalent later in the summer. 
  
“With transient water mosquitoes, we have to be careful because it’s not only the water we see, but it’s also the water we don’t see, like in storm drains, where these mosquitoes can breed in significant numbers, which could cause an impact and disseminate West Nile,” Talley said. 
  
Although Zika has not yet been found in Oklahoma, West Nile will always be a challenge across the state, Talley said. 
  
“Keep in mind there’s actually a very low percentage of mosquitoes that are infected with these types of viruses,” he said. “There’s no way to tell which is an infected mosquito versus an uninfected mosquito. You need to treat all mosquitoes equally, protect yourself and get rid of any standing water on your property.”