With nationwide measles infections climbing past 4,000 this year to reach the highest annual count since 1991, health specialists are offering guidance to adults who are uncertain about their immunization records, according to reports from NPR and Yahoo Creators.
Surging outbreaks have heightened concerns across several regions. Pennsylvania has recorded more than 1,000 cases and five fatalities, while New York Gov. Kathy Hochul declared a statewide disaster emergency, NPR and Findlay News reported. Public health officials say waning vaccination rates have left pockets of communities vulnerable to the airborne pathogen, which can infect up to nine out of 10 unprotected people who are exposed.
Evaluating your immunity and birth year
Whether you require another shot often depends on when you were born and your vaccination history. Individuals born before 1957 are widely considered immune because the virus was so pervasive during their childhood that infection was virtually inevitable, Dr. Larry Kociolek, an associate professor at Northwestern University Feinberg School of Medicine, told NPR. Those who previously survived measles possess lasting natural protection.
However, people born after 1957 who received shots before 1968 may need an updated injection. During that era, some patients were given an early killed-virus formulation that was less potent than modern options, NPR reported. In such cases, the Centers for Disease Control and Prevention recommends discussing one or two updated doses with a medical provider.
The standard vaccination schedule also shifted over time. The U.S. began advising two childhood doses of the measles, mumps, and rubella (MMR) vaccine in 1989 after finding a single shot insufficient to halt community spread. A single MMR dose provides about 93 percent protection, whereas two doses raise effectiveness to roughly 97 percent, according to the CDC.
The safety of receiving an extra dose
Adults who grew up before the two-dose schedule became common, or who cannot locate physical records, may wonder whether receiving an additional shot is dangerous. Epidemiologists say there is no medical risk in receiving a second or even a third dose if prior history cannot be confirmed.
“I would say it is easier and less expensive to just get another MMR vaccine, and there is no harm in getting a second MMR vaccine or even a third, additional MMR dose,” Dr. William Moss, a professor of epidemiology at Johns Hopkins Bloomberg School of Public Health, told NPR.
While individuals can request blood tests to measure measles antibodies, specialists point out that laboratory testing can generate false negatives and might not be fully covered by insurance plans. By contrast, most private insurers and Medicaid cover MMR immunizations at no out-of-pocket cost, NPR reported. Experts advise those who are immunocompromised or pregnant to consult a physician prior to vaccination, as they cannot safely receive the MMR vaccine and depend on surrounding community protection.
Severe complications drive urge for protection
Public health advocates emphasize that measles carries serious medical risks far beyond a fever and rash. The virus can cause immune amnesia, a phenomenon where the immune system temporarily loses antibodies built up against other previously encountered diseases, Findlay News and Yahoo Creators reported.
The American Academy of Pediatrics estimates that roughly 30 percent of measles cases develop complications, ranging from pneumonia to encephalitis. A rare, fatal central nervous system condition known as subacute sclerosing panencephalitis can also manifest seven to 10 years after infection, especially among those who contracted the virus in infancy.
Health officials advise anyone experiencing potential measles symptoms to telephone clinics or emergency rooms before arriving in person so facilities can implement infection controls.
