Trial of Jynneos mpox vaccine begins in infants, toddlers, pregnant women

News brief

mpox vaccine vial — Diane A. Reid / Wikimedia Commons

Bavarian Nordic said today that the first of two clinical trials of the use of its Jynneos (MVA-BN) mpox/smallpox vaccine has begun in vulnerable populations: infants and children 2 years old and younger, and pregnant or breastfeeding women.

The first participants have been vaccinated in a study to evaluate the safety and immunogenicity of Jynneos in 344 infants aged 4 to 24 months. Recruitment has also started in a second safety and immunogenicity study, which will enroll 359 pregnant or breastfeeding women. Both studies will be conducted in the Democratic Republic of the Congo, the epicenter of an ongoing mpox outbreak that includes babies, young children, and pregnant women.

Funded by EDCTP3, CEPI

Bavarian Nordic President and CEO Paul Chaplin, PhD, said, "These new studies will fill the gap by providing important data about the use of MVA-BN in infants and pregnant women, and we applaud the study partners as well as the funding partners, EDCTP3 and CEPI [Coalition for Epidemic Preparedness Innovations] for supporting this important work, which could help support a label expansion for MVA-BN to include the most vulnerable populations."

Both studies are part of the PregInPoxVac research project, led by the University of Antwerp and the University of Kinshasa.

In addition, Bavarian Nordic is sponsoring a trial of Jynneos in children aged 2 to 11 years old, which has received funding support from CEPI. It expects results from this trial later this year.

Measles cases confirmed in Washington, Virginia

News brief

Stephanie Soucheray, MA

More measles cases have been reported in Washington state. Officials in Seattle-King County yesterday reported two measles infections in the same household, a child and an adult who were likely exposed while hosting an international traveler.

The traveler reported feeling ill but left King County with their measles status unknown. The two individuals visited multiple locations throughout King County while infectious.

The child had one dose of the measles, mumps, rubella vaccine and the adult’s vaccination status is unknown at this time. Washington state now has 10 measles cases recorded in 2025.

Virginia looks at Dulles exposure

Virginia's health department is investigating another potential measles exposure at Dulles International Airport, in an international traveler who was visiting North Carolina.

“Health officials are coordinating an effort to identify people who might have been exposed, including contacting potentially exposed passengers on specific flights,” officials said. Virginia has three reported cases of measles to date in 2025.

Maryland survey reports 62 CWD-positive deer in 2024

News brief

Chris Dall, MA

An annual survey from the Maryland Department of Natural Resources revealed that 62 white-tailed deer sampled in 2024 tested positive for chronic wasting disease (CWD).

The survey also found that all but one of the positive samples for the fatal prion disease came from within the state's CWD management area, which includes Allegany (34 positive sample), Baltimore (0), Carroll (0), Frederick (7), Montgomery (3), and Washington (17) counties. CWD was also detected in Howard County for the first time, resulting in an expansion of the CWD management area.

CWD was first confirmed in Maryland in 2011, and the new findings bring the state's total of confirmed cases to 285.

CWD continues to spread

"Unfortunately, chronic wasting disease continues to spread nationally, regionally, and within the state of Maryland," Wildlife and Heritage Service Director Karina Stonesifer said in a department press release. "As the disease spreads within Maryland, we will continue to monitor it closely to provide the public with reliable information and manage the impact on our deer herd."

CWD effects cervids such as deer, elk, and moose, spreading through cervid-to-cervid contact and environmental contamination. A slow and progressive disease caused by misfolded prions, it affects animals' brains and is ultimately fatal.

Maryland is one of 36 states where CWD has been documented. Although no human cases of CWD have been reported, health officials warn the public not to eat the meat of infected animals. CWD management areas help keep hunters informed, regulate how deer carcasses are transported, and help slow the spread of the disease.