The January measles outbreak in the western U.S. has made vaccination a hot topic in the media, and even the subject of heated political debate. Here are some vaccination facts to help clear up some popular misconceptions.
Getting vaccinated not only prevents you from getting an infectious disease; it protects your family and the people in your community. To prevent a measles outbreak, for example, 95 percent of the population must be vaccinated. In every community there are people who cannot be vaccinated for health reasons, as well as people who did not develop immunity after being vaccinated. For example, babies cannot be vaccinated against measles until they are one year old. Elderly people might never have received vaccinations, or their immunity might have diminished over time. If one unvaccinated person brings a disease into the community, all of these people will also get sick. It is not unusual for a traveler to bring a disease from another part of the world where vaccination rates are low.
There are two good reasons why doctors give babies several shots at one time. Some parents are alarmed when their baby receives multiple vaccinations during a wellness visit. Immunization schedules are designed to protect the most vulnerable patients from disease. Very young children are most likely to be infected by the diseases the vaccines are designed to prevent, and to suffer serious complications. Doctors want to vaccinate children as early as possible; delaying vaccinations increases the risk that the child could contract a serious disease. Multiple vaccines given at one time do not overwhelm the immune system, and giving several at one time reduces the stress and anxiety of having to return to the doctor's office again and again for injections.
No vaccine is 100% effective. Most routine childhood vaccines are effective for 85% to 95% of recipients. Some individuals will not develop immunity when they are vaccinated against a disease.
The MMR vaccine does not cause autism. In 1998, a controversial paper linking the MMR vaccine to autism triggered an anti-vaccination movement. Afterwards, studies showed that there is no connection between autism and the MMR vaccine and the magazine publicly retracted the paper. Thimerosal, a mercury-based preservative, has not been used in childhood vaccines since 2001.
Adults need shots too. Vaccinations don't end with childhood. Immunity to some diseases, like whooping cough and tetanus, wears off as you get older. The Centers for Disease Control recommends a tetanus booster every ten years. New vaccines have recently been developed, like the HPV vaccine and shingles vaccine, which were approved in 2006. As adults get older, they become more susceptible to pneumonia, shingles, and influenza.
Vaccination, not improved hygiene, is responsible for the drop in infectious diseases in the U.S. The U.S. had between 300,000 and 800,000 cases of measles every year between 1950 and 1963, when a new measles vaccine came into use. In 1968 there were only about 20,000 cases, and by 1998 the number of cases per year was about 100. A similar drop occurred with most diseases for which vaccines are available. The World Health Organization (WHO) credits immunization efforts for a nearly 75% reduction in global measles deaths from 2000 to 2007.
The risks of natural infection outweigh the risks of immunization for every recommended vaccine. Serious side effects after vaccination are very rare. A childhood illness can not only be unpleasant and debilitating, but can cause complications and permanent damage to a child's health. The CDC reports that 1 in 10 children with measles also gets an ear infection; up to 1 in 20 gets pneumonia; about 1 out of 1,000 gets encephalitis; and 1 or 2 out of 1,000 die. Measles can also make a pregnant woman miscarry or give birth prematurely. High fever and secondary infections can cause hearing loss or brain damage.
If you have concerns about vaccinating your children, or about vaccinations for yourself, talk to your doctor or pediatrician.