Mpox Vaccination Recommended for All Adults at Risk

The U.S. CDC published a Morbidity and Mortality Weekly Report (MMWR) today that concluded all adults at risk for mpox should receive Bavarian Nordic JYNNEOS® (MVA-BN) vaccine, irrespective of childhood smallpox vaccination status.

Immunologic studies have demonstrated some long-term immunologic memory from childhood smallpox vaccination that is cross-protective against mpox. Still, such immunity might have waned by May 2022, when the global outbreak began.

On August 18, 2023, the MMWR disclosed although persons aged >50 years likely received a childhood smallpox vaccination, they might have more comorbidities and a higher risk for severe mpox than those aged ≤50. 

This study found among 29,984 adults with mpox, those aged >50 years had higher prevalences of immunocompromising conditions and HIV and lower prevalence of symptoms than younger people.

Among 1,020 adults aged >50 with vaccination data, prevalences of pruritus, constitutional symptoms, and hospitalization were lower among those who received the JYNNEOS vaccine than those who had not.

This finding underscores the importance that persons at risk for mpox, particularly adults aged >50 years, receive the recommended JYNNEOS vaccination. JYNNEOS vaccination is recommended for all adults at risk for mpox irrespective of receipt of childhood smallpox vaccination, wrote these researchers.

The JYNNEOS vaccination services remain available in most health clinics and pharmacies in U.S. cities, London, and in various other locations.

It's unknown how long JYNNEOS protection last or if protection might decrease over time, says the CDC. 

On August 3, 2023, the U.S. government ordered an additional $120 million worth of JYNNEOS vaccines.