According to the vaccine's maker, Valneva, the FDA based its decision to suspend the shot on four new serious adverse events that happened outside the U.S., three of which were in people ages 70 to 82 years and the other in a 55-year-old individual.

The US Food and Drug Administration (FDA) announced late last week that it has suspended the license for French drugmaker Valneva's chikungunya vaccine, saying that continued administration of the vaccine to the public would pose a danger to health.

Less than three weeks after lifting a pause on the use of Valneva’s chikungunya vaccine Ixchiq, the FDA has done an about-face, banning the use of the shot in the United States. | Less than three weeks after lifting a pause on the use of Valneva’s chikungunya vaccine Ixchiq,