Peak mosquito season is coming up across the Valley, with conditions over the next several weeks just right for breeding.

One medical doctor is worried conditions in countries south of the U.S. could lead to the resurgence of a virus we haven't seen in more than 100 years.

"We've not had Yellow Fever on the Gulf Coast since 1905. I'm concerned that in Latin America and Brazil and Venezuela we've seen an uptick and spread to new areas," Dean of the National School of Tropical Medicine Dr. Peter Hotez said.

Dr. Hotez says over the last seven years, there have been Yellow Fever outbreaks in South American countries, increasing the odds the virus may spread across borders.

"Here in South Texas, Yellow Fever is not common. I'm not saying it's not going to happen, but we have seen an increase in Malaria. Malaria is not common to us here in the Valley. We have the annual cases of Dengue and West Nile, Chikungunya," Hidalgo County Health and Human Services Chief Administrator Officer Eddie Olivarez said.

Olivarez says cites, school districts and the county will continue monitoring mosquito breeding.

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