If you think you're safe from diseases that you were vaccinated for, you may not be. Not everyone is entirely immune, including completely vaccinated people.
Science NOW reported on Friday, a person fully vaccinated against measles contracted the disease and passed it on to others. This contradicts the messages and information that doctors have repeated about vaccines and immunity.
When it comes to the measles, mumps, rubella vaccine (MMR), two shots are required. Children are initially vaccinated after their first birthday and get a booster as a toddler. Less than one-percent who get both shots are believed to be immune. That is until now, as researchers tracked back a measles outbreak that started with a fully vaccinated person.
A 22-year-old woman in New York City who developed the measles in 2011 was released without hospitalization or quarantine. She transmitted the measles to four other people, according to a recent report in Clinical Infectious Diseases that tracked symptoms in the 88 people with whom “Measles Mary” interacted with. Ironically, two of the secondary patients had also been fully vaccinated.
By analyzing "Measles Mary's" blood, researchers found that she mounted an IgM defense, as if she'd never been vaccinated.
While public health officials have assumed that measles immunity lasts forever, the case of "Measles Mary" shows the reality that “the actual duration of immunity following infection or vaccination is unclear,” according to Jennifer Rosen, who led the investigation as director of epidemiology and surveillance at the New York City Bureau of Immunization.
It's possible that vaccinated people may lose their immunity as they get older. That would leave them vulnerable to measles.