Alert Issued Regarding Mpox Vaccine Breakthrough Cases

The U.S. Centers for Disease Control and Prevention (CDC) announced a Health Alert Network Health Update today to inform clinicians and public health agencies that the mpox outbreak is not over.

As of May 15, 2023, the CDC continues to receive reports of mpox cases that reflect ongoing community transmission in the U.S. and Europe (France).

For example, from April 17 to May 5, 2023, a total of 12 confirmed and one probable mpox case was reported to the Chicago Department of Public Health.

Unfortunately, nine (69%) of 13 cases were among men who had received both doses of the U.S. FDA-approved JYNNEOS® (MVA-BN) vaccine.

The travel history was available for nine men; 4 recently traveled (New York City, New Orleans, and Mexico).

Although vaccine-induced immunity is not complete, vaccination continues to be one of the most important prevention measures, says the CDC.

However, data posted by the CDC on December 8, 2022, indicates the effectiveness of one JYNNEOS dose was 37%, two doses were 69%, and the duration of immunity is unknown. 

The CDC announced on February 22, 2023, the Interim Clinical Considerations mpox vaccination should continue to be offered to people with the highest potential for exposure to mpox.

Furthermore, the CDC expects additional mpox cases among previously vaccinated people to occur during the spring and summer seasons in 2023 as people gather for festivals and other events.

Additional mpox outbreak news is posted by Precision Vaccinations.