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Measles immunizations are widely regarded by the medical community as being safe. There are a number of recorded side effects, but the vast majority are quite mild — and all are usually better than actually contracting the measles virus. The most common reactions are skin rashes and low-grade fevers; neither is contagious, and each usually lasts for no more than about a week. In very rare cases patients can experience blood problems, particularly low platelet counts, and allergic reactions. In most places, the vaccine is recommended if not required for almost everyone. Some of the only people who shouldn’t get a measles vaccine are pregnant women, infants under one year of age, and people who suffer from severe immune deficiency. It can be unsafe in these limited circumstances, but there are usually other things people in these situations can do to limit their susceptibility to the virus.
How it Works
All immunizations, measles included, are designed to help the body build up a tolerance and immunity to a particular virus so that the body will never actually contract it if exposed. The measles vaccine typically contains a denatured or “dead” version of some of the virus’ most aggressive cells. They are not live and they cannot actually infect a person, but they carry the essential genetic coding that allows the person’s immune system to create a tailored response. As such, if and when that person encounters an actual strain, the body will already know how to respond and won’t become infected.
The measles vaccine was first available in 1963 as a single-shot vaccination. In 1973, the measles, mumps and rubella (MMR) vaccine became widely available in many places, promoting efficiency and better public health. The MMR vaccine is used in many countries instead vaccines against the diseases individually, but single-shot vaccines still are used in some places. A lot depends on local resources and health guidance. These vaccines generally are given to children between 12 and 15 months of age, though some adults also receive them. Boosters are often recommended for adults and older children who are likely to be exposed, for instance, as well as for people who received some of the earliest compounds in the 1960s and ‘70s.
Most Common Side Effects
The most common side effects of the measles vaccination include fever and a mild rash. Most studies estimate that fever occurs in anywhere from 5-15 percent of the people who receive the vaccine, and 5 percent of recipients will likely get a mild rash. Rashes often start at the site of the injection, though they can often spread; they are also common on the torso, particularly on the stomach and across the back.
Both the rash and fever tend to appear seven to 12 days after the immunization and are fairly short in duration. Neither is contagious. Sufferers often feel like they have lower energy and may prefer to rest at home, but there isn’t any health reason why they should refrain from attending school or going to work.
More Serious Reactions
Less common side effects include allergic reaction and low platelet count, both of which can be quite dangerous. Allergic reactions are typically a result of an adverse reaction to one or more of the ingredients in the vaccine. Most medical shots are made up not only of the denatured virus but also a number of suspension and stabilizing components, gelatin and neomycin being two of the most common. Reported allergy cases have almost always been related to these additional ingredients, not to the virus itself.
Thrombocytopenia, or low platelet count, is often short-lived and is experienced by about one in every 35,000 recipients. In the most serious cases it can cause problems with blood clotting and organ functionality, but this is very rare.
The most extreme side effects of measles immunization might include deafness, coma or permanent brain damage. These severe reactions have been recorded in some limited studies, but because they happen so rarely, medical officials have not been able to establish a definite cause-and-effect relationship between the vaccination and these issues. A lot may have to do with individual body chemistry and preexisting conditions. Experts almost unanimously say that the potential risk of these more serious consequences should not cause a person to forego the vaccine, since the benefits and the chances of it working are so much more likely — and also so important from a public health perspective.
Concerns with Pregnancy and Autoimmune Conditions
Most medical professionals consider women who are pregnant and people with serious immune system compromises to be in something of a class of their own where vaccines are concerned. In most cases standard measles vaccines aren’t safe for people in either category. Even though the virus is denatured, it can be harmful to fetuses since fetal immune systems haven’t usually developed enough to create protections. The unborn child won’t get measles, but could end up with serious defects or other health issues as a result of the vaccine. It is for similar reasons that a measles immunization isn't usually administered to infants under one year of age.
Similarly, people who suffer from a disease that severely compromises the immune system, such as acquired immune deficiency syndrome (AIDS), leukemia or lymphoma, often lack the immune strength to build up a resistance to the virus. The injection can overstress the already fragile body and can lead to a host of infections and organ failures, some of which can be fatal. The vaccine is not generally recommended for people who are undergoing treatment for cancer with radiation, drugs or large doses of corticosteroids for largely the same reasons.