Updated

An unvaccinated 39-year-old woman became the sixth measles death in Pennsylvania, with state health officials reporting 1,136 cases across 41 counties as of Friday. The outbreak has renewed public health concern about vaccination gaps, prompting guidance for adults unsure of their immunity status. Health officials and reporters note that for most adults a single MMR shot is sufficient, but certain situations call for a booster dose. The continuing spread highlights the risks of declining vaccination rates in some communities.