MedPage TodayBreakthrough Monkeypox Cases Seen Weeks After Second Jynneos Dose

Aniruddha Hazra, MD, of Howard Brown Health in Chicago, and colleagues found that of 90 people who tested positive for monkeypox following a single dose of Jynneos, 77% of the cases happened within 14 days of the first dose and 14% occurred within 14-28 days of the first dose. Five positive tests were returned following a second dose of the modified vaccinia Ankara-Bavarian Nordic (MVA-BN) vaccine in the eight cases that occurred 28 days after vaccine initiation.