Yellow Fever Spreading in the Americas

“The extensive outbreak of yellow fever now occurring in Brazil deserves careful attention by world health authorities”, noted Anthony S. Fauci, M.D., director of the National Institute of Allergy and Infectious Diseases (NIAID).

In its most serious form, yellow fever symptoms include high fever, hemorrhagic manifestations, kidney failure, liver malfunction and jaundice (yellowish appearance of the eyes and skin, which gives the disease its name.)

Known today to be spread by infected mosquitoes, yellow fever was long believed to be a miasmatic disease originating in rotting vegetable matter.

Dr. Fauci and his associate, Catharine I. Paules, M.D., noted “This outbreak of a serious mosquito-borne virus comes as Zika virus, which is spread by the same mosquito as yellow fever virus, continues to affect countries throughout the Americas.”

The Brazilian outbreak is a manifestation of the “sylvatic,” or jungle, transmission cycle in which forest-dwelling mosquitoes spread the virus primarily to non-human primates, with humans serving only as incidental hosts.

Historically, yellow fever has claimed millions of lives, including thousands in the United States. The first recorded American yellow fever epidemic was reported in Philadelphia, during July 1793. This outbreak killed thousands of people, as Philadelphia was the nation’s capital, and the most cosmopolitan city in the United States.

According to the NIAID, a yellow fever vaccine has been available since 1937 and confers lifelong immunity in up to 99 percent of those who receive it.

An urban cycle of yellow fever in Angola and the Democratic Republic of Congo that began in late 2015 caused 961 confirmed cases and 137 deaths.

According to Dr. Fauci, “In an era of frequent international travel, an increase in domestic cases in Brazil has the potential to spread yellow fever to non-endemic areas and could pose serious disease-control challenges.”

Additionally, Dr. Fauci observe, “We urge clinicians, especially those in the United States to inform themselves about yellow fever symptoms and to adopt a high index of suspicion for this diagnosis, particularly when examining travelers returning from affected regions.”