The United States has halted the use of the Ixchiq vaccine for chikungunya following reports of serious side effects, including cases involving elderly patients.
The vaccine, produced by French company Valneva, is one of only two approved by the US Food and Drug Administration for the mosquito-borne virus, which spreads mainly in tropical and subtropical regions but has been reported in more countries worldwide in recent years.
Valneva announced the suspension on Monday, saying the FDA ordered the action on Friday after four more cases of severe reactions were recorded. Three of those cases involved patients between 70 and 82 years old.
“The suspension of the license is effective immediately,” the company said in a statement.
Valneva’s chief executive, Thomas Lingelbach, stressed the importance of the vaccine in tackling the disease. “As we determine potential next steps, and as the clear threat of chikungunya continues to escalate globally, Valneva remains fully committed to maintaining access to our vaccine as a global health tool,” Lingelbach said.
Health experts have warned that climate change is helping mosquitoes spread to new areas, raising the risk of chikungunya becoming a larger global health problem.
The World Health Organization in July warned of signs of a major outbreak similar to one two decades ago that swept across the Indian Ocean and spread globally, infecting nearly half a million people.
This year alone, Europe has recorded 27 chikungunya outbreaks, the highest number on record, according to the European Centre for Disease Prevention and Control.
Chikungunya causes high fever and severe joint pain, with symptoms often similar to dengue fever and Zika virus. While it is rarely fatal, the disease can be dangerous for babies and the elderly.
