U.S. doctors fear yellow fever could come from Brazil
Yellow fever has a relatively high death rate and "is the most severe [insect-transmitted] virus ever to circulate in the Americas," Fauci and Paules wrote.
"Although it is highly unlikely that we will see yellow fever outbreaks in the continental United States... it is possible that travel-related cases of yellow fever could occur, with brief periods of local transmission in warmer regions such as the Gulf Coast states, where A. aegypti mosquitoes are prevalent," the team added.
According to the experts, yellow fever has the potential to be the fifth mosquito-borne infection to appear in the continental United States since the 1990s, following dengue, West Nile, chikungunya and the Zika virus.
Yellow fever is perhaps the most dangerous of those five, however. In one outbreak that began in the Congo in December 2015, there were 137 deaths among 961 confirmed cases, the report noted.
And in the current Brazilian outbreak, there have so far been 234 cases and 80 confirmed deaths, according to health authorities.
More ominous in the Brazilian outbreak is the fact that the illness appears to be moving from its typical rural setting towards the cities.
"The outbreak is affecting areas in close proximity to major urban centers [in Brazil] where yellow fever vaccine is not routinely administered," Fauci and Paules warned.
The authors stressed that there's yet no evidence that mosquitoes are transmitting yellow fever between infected people. However, the advent of outbreaks near urban centers "raises concern that, for the first time in decades, urban transmission of yellow fever will occur in Brazil," they explained. ■