“Culex is a much more abundant species,” Ayres told a news conference in Rio de Janeiro on Thursday, where she presented theresults.

The researchers analyzed 456 female Culex mosquitoes, which they divided into 80 “pools” or sample groups of between one and 10 mosquitoes each. They found Zika-infected insects in three of these pools.

Ayres said the research proved that Culex can transmit Zika and that it could have played a role in the rapid spread of the disease in Brazil.

“It can transmit Zika. What we need to know now is which species is the most important — if Culex is the primary vector or the secondary vector. We need to do more research,” she said.

Paulo Gadelha, president of the Oswaldo Cruz Foundation, expressed some caution during Thursday’s news conference. He said that a study at the institution in Rio by researcher Ricardo Lourenço-de-Oliveira had so far failed to find Zika in around 750 Culex mosquitoes.

“It could be that mosquitoes circulating in the Northeast [of Brazil] have more interaction,” he said, stressing that more research was needed.

Gadilha said the discovery did not change the low risk of Zika during Brazil’s Olympics, which open in Rio on Aug. 5 during the country’s cooler winter season. “The risk you have of Zika during this period is very, very remote,” he said.

 

Peter Hotez, dean of the National School of Tropical Medicine at Baylor College of Medicine in Texas said that if researchers have found Zika in Culex mosquitoes only a handful of times, “it’s hard to know what that means; it may not be a finding of great biological significance.” But if they are detecting the virus in Culex mosquitoes in large numbers and on a consistent basis, “That would be a game changer.”

Hotez was skeptical that Culex mosquitoes are going to start spreading Zika in a significant way. “So far, every place we’ve seen Zika has been a place where you have Aedes aegypti mosquitoes,” he said. “There no reason why one would have to speculate that another mosquito vector is involved.”

https://www.washingtonpost.com/world/the_americas/zika-is-found-in-common-culex-mosquitos-signaling-a-potentially-larger-risk/2016/07/21/e1b37e0e-4f6f-11e6-bf27-405106836f96_story.html