US health authorities have issued a warning to older travellers after two deaths were reported following vaccination against a mosquito-borne disease.
The preventative jab against the viral chikungunya disease – transmitted by Aedes mosquitoes, the same species that spread dengue and Zika viruses – was approved in November 2023 by the FDA.
Most people recover from the illness within a week, and deaths are rare, but people with other health conditions may be at higher risk.
The Ixchiq vaccination, developed by Valneva to prevent chikungunya virus, is the first of its kind, and approved for anyone 18 and older who risk being exposed to the virus.
But the FDA and the Centres for Disease Control and Prevention (CDC) released a safety notice on 9 May recommending that adults over 60 avoid the vaccine due to fatal complications.
“FDA and CDC will continue the evaluation of post-marketing safety reports for Ixchiq,” the notice said.
According to Fox News, the advisory follows reports of “serious adverse events”, including neurological and cardiac events in people who received the vaccine.
Two of 17 events resulted in death from severe complications. One death was caused by encephalitis, or inflammation in the brain, the alert stated.
Those who experienced adverse effects of the vaccine were aged between 62 and 89.
The FDA warned that Ixchiq, which contains a live, weakened version of chikungunya, may cause symptoms similar to the virus.
At the time of the vaccine’s approval, the FDA described chikungunya as an “emerging global health threat”, with at least 5m cases having been reported over the past 15 years.
Fox News article – FDA warns seniors to avoid this vaccine after deadly complications (Open access)
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