Have been vaccinated or have ever had measles still

Have you been vaccinated against measles, and you will not get measles anymore - or will you not infect measles anymore? This is not always true.

>>>The most serious epidemic in decades

A person who has been fully vaccinated can still get measles infection and spread measles to others. This startling study contradicts what people often think, and raises the risk of measles outbreaks in developed countries, among people who have been vaccinated.

For measles vaccines, two injections are better than just one shot. Most people in the United States have vaccinated against measles as soon as they are 1 year old, and have another injection when they are toddlers. Less than 1% of people who have two injections of measles have measles. Even if a person has been fully vaccinated with measles - this is a rare case when the vaccine does not work - they are also not considered infected.

That's why a 22-year-old theater staff member in New York had a full measles vaccination and got measles in 2011 but still doesn't have to be hospitalized or quarantined. However, according to a recent report of the Prevention of Infectious Diseases organization, she infected measles to 4 others. Surprisingly, two of these patients were fully vaccinated. And even though the other two have not been vaccinated against the disease, they all have signs of being exposed to measles before. Maybe these cases are immune, but they still have measles.

A closer study of blood samples during the treatment of the theater staff showed how the measles immune mechanism was broken. When initially fighting measles virus and other bacteria, the body relies on the natural resistance of IgM antibodies . Like a shield, they protect the body against bacterial invasion, but are not inviolable. Vaccine (or the case of measles infection) will prompt the body to support this series of shields with stronger IgG antibodies, some of which may neutralize measles virus, so they cannot invade cells. or spread to other patients. This immune mechanism has been around for decades.

But by analyzing the patient's blood sample, the researchers discovered the measles virus that resisted IgM antibodies, as if the patient had never been vaccinated. Her blood also contains an inventory of IgG antibodies, but further research shows that no IgG antibodies are actually capable of neutralizing measles virus. It seems that the immune regime that the vaccine gives to the body has weakened.

The long-term immunity regime after vaccination or once infected is unclear

Although public health officials hypothesize that measles immune mechanisms persist forever, the above- mentioned duet shows that "the long-term immune regime after vaccination or disease is unknown Clearly, " said Jennifer Rosen, who led the investigation and is director of the New York City epidemiology center. Weakened immunity is particularly worrisome when measles viruses are appearing in major US cities such as Boston, Seattle, New York, and Los Angeles.

Rosen does not believe that this situation leads to a change in the vaccination program - for example, people should continue to take additional shots - but she said more frequent monitoring is needed to assess the strength of the immune system. Measles virus.

If people who have been vaccinated lose their immunity when they get older, they can get sick by people who have not been vaccinated. Even if the rate of vaccine failure is only 3% -5%, it can cause a high school with several thousand students to become ill.