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U.S.
Food and Drug Administration |
This article originally appeared in the March 1994 FDA Consumer. The version below is from a reprint of the original article and contains revisions made in October 1995 and February 1999. |
Yet other diseases persist, mostly in unvaccinated babies and toddlers--the children who are most vulnerable to the effects of disease. An estimated 37 percent to 56 percent of American children are not fully immunized by age 2, according to CDC. In some inner city areas, only 10 percent of children have been properly immunized.
Some people blame the low rates on inconvenience. There are 11 diseases to vaccinate against, with as many as 16 doses in about five visits to the doctor before a child's second birthday.
Others point out that parecnts are required to have children vaccinated only before enrolling them in school or day care. Ninety-six percent of children have their shots before entering school, according to CDC. But babies and toddlers not in licensed day care are most likely to miss their shots.
The cost of vaccines may be another factor in low immunization rates. According to CDC, vaccines for one child in 1993 cost about $89 in the public sector and $213 in the private sector, in addition to administrative fees usually charged. Only half of health insurance plans cover childhood vaccines, though many public health departments offer them free or at a reduced fee based on income. Congress allocated $500 million for fiscal year 1994 to provide free vaccinations to all uninsured children and to educate parents about the need for childhood immunizations.
Education is necessary, physicians say, because many parents do not understand how dangerous childhood illnesses are.
"They're not real in people's minds," says Donald S. Gromisch, a spokesman for the American Academy of Pediatrics and a member of its committee on infectious diseases. "Years before the whooping cough vaccine, many children died of whooping cough. In inner cities a few years ago where vaccination rates are dismal, people continued to die [of whooping cough]."
In fact, diseases that are uncommon in most parts of the United States today are nearly epidemic in American communities where children are not properly vaccinated.
Measles, for instance, had dropped to a record low of fewer than 1,500 cases in 1983, according to CDC. A resurgence of measles between 1989 and 1991, however, resulted in 55,000 cases and 132 deaths, mostly among unvaccinated babies and toddlers. In urban areas, minority children are four to nine times as likely to get measles as white children.
The resurgence of childhood illnesses costs money as well as lives. According to the National Academy of Sciences' Institute of Medicine, every $1 in vaccinations saves $10 in later health-care costs.
Whether a child receives vaccinations at a pediatrician's office or health department, the health-care provider is expected to keep careful records of when each shot was given and what brand it was. Some brands have slightly different schedules than others. Parents should ask for copies of the shot record to keep at home as a reminder for the next round.
Even if a child misses an appointment, it's possible to catch up. Says Gromisch of the AAP, "Usually it's not too late. In general, if you miss a vaccine, you can get it the next time around."
Required Vaccines
Immunization schedules have changed in recent years. Several new vaccines have been added, and old ones have been reformulated to be safer than ever. Here is a list of vaccinations recommended for children.
Hib
Before the vaccine to protect against Haemophilus influenzae type b, this bacterial infection struck 1 child in 200 before the fifth birthday. Of those, 12,000 children a year developed meningitis, which killed 1 in 20 and caused brain damage for 1 in 4. Hib can also infect blood, joints, bones, soft tissues, the throat, and the membrane surrounding the heart.
Hib vaccines are the latest development among childhood immunizations, and their benefits have been far-reaching. The first conjugate Hib vaccine was available in 1987 for children 15 to 18 months old. But in 1990, FDA licensed the first vaccine effective in babies under a year old, the age group in which Hib infections are most damaging.
Hib vaccines are "conjugate" vaccines, made up of small pieces of bacterial polysaccharides, or sugars, linked to proteins. They have nearly eradicated Hib infections among vaccinated children in the United States, according to CDC.
FDA has licensed four Hib vaccines, including a combination of other vaccines mentioned earlier. The most recently approved vaccine is distributed in the United States under two brand names, OmniHib and ActHIB.
Depending on the brand of vaccine, Hib is given in either three or four doses by the time the child is 12 to 18 months old. Side effects are very minor, consisting mostly of low-grade fever and soreness at the site of the shot.
DTP
The DTP shot is a combination inoculation against diphtheria, tetanus and pertussis. It is given at 2, 4, 6, and 15 to 18 months of age, with a booster between 4 and 6 years.
Diphtheria is an infection of the throat, mouth and nose. It's extremely rare today, but highly contagious. The infection causes a sore throat and cough. Sometimes a fine web of gray membrane forms over the tonsils, blocking the windpipe and suffocating the child. If not promptly treated, diphtheria can also lead to pneumonia, heart failure, and paralysis.
Pertussis, or whooping cough, is life-threatening, especially in children under 1 year. It's caused by a bacterium that clogs the airways with mucus, causing a severe cough that sounds like a "whoop." The coughing can last two months, inviting other infections such as pneumonia or bronchitis.
The pertussis component of DTP causes more adverse reactions than any other vaccine. Most common are fever, soreness at the site of the shot, and irritability. In rare cases, the vaccine causes very high fever and convulsions.
FDA licensed in 1992 a version of the pertussis vaccine with potential for fewer local and febrile reactions. Unlike the old version, which is made from whole cells of pertussis bacteria that have been killed, the new vaccine is "acellular," made from portions of the cells. It has fewer side effects and has been approved for the fourth dose, given between 15 and 18 months, and the last dose, given before school entry. Several acellular pertussis vaccines are now licensed for infants.
Tetanus is a rare infection caused by bacteria found in dirt, gravel and rusty metal. It enters the body through a cut, creating a toxin, or poison, that causes the muscles to spasm. The toxin attacks jaw muscles first, often resulting in lockjaw. Tetanus can also cause the breathing muscles to spasm, resulting in death for 3 out of 10 people who get it.
The primary series of tetanus shots is given as part of the DTP shot during infancy. After that, the tetanus vaccine should be given as a booster every 10 years throughout life.
Hepatitis B
Hepatitis B is a viral disease transmitted through blood and body fluids. In its acute phase it can cause liver failure and death. It can also become chronic, causing liver damage, including cancer, over a number of years.
Except for infants born to mothers with this infection, children are not at great risk of developing hepatitis B, but health-care workers, homosexuals, and intravenous drug users are. Attempts to vaccinate adults have been largely unsuccessful, however. It's easier to reach children because school enrollment requires immunization.
Therefore, for lifelong protection, CDC has recommended that all infants be vaccinated before 15 months of age in three doses. There are no serious reactions to the vaccine.
Polio
Polio is remembered by many older Americans as a frightening disease that was epidemic during the 1950s. In 1952, more than 20,000 people--mostly children--were afflicted, according to CDC. Polio's first symptoms are fever, sore throat, headache, and stiff neck. The potentially fatal disease can soon progress to paralysis of the lower limbs and chest, making walking and breathing difficult or impossible. There is no cure for the disease.
There are two polio vaccines. One is an inactivated polio vaccine (IPV) in which the polio virus has been killed. Licensed in 1955, this vaccine is injected into the patient. The second vaccine is made from live attenuated (weakened) polio viruses. This oral polio vaccine (OPV) was licensed in 1963 and is taken as drops in the mouth.
Since the development of the oral vaccine, the incidence of polio has dropped to fewer than 10 cases per year. In fact, the oral vaccine has entirely prevented polio caused by the wild virus (not vaccine related) in North and South America since 1991, according to the Pan-American Health Organization.
However, the oral vaccine itself does cause paralytic polio in a very few children who received the vaccine, and in a few adults who came in close contact with recently vaccinated children. The risk of contracting polio this way is no more than 1 in 1.5 million. It is greatest for people who have immune deficiencies such as AIDS, cancer, or other diseases that make it hard for the body to fight infection. Because of this risk, CDC recommends that IPV be given for doses one and two to all children. Those who have immune deficiencies or who live with adults who do should only be given IPV. Parents who have not been vaccinated for polio should consider getting vaccinated with IPV before the child receives the oral vaccine.
A number of lawsuits have been filed against Lederle Laboratories, Inc., manufacturer of the oral vaccine. While the government was found negligent in its applications of some regulations on vaccine approval and vaccine lot release, the court has nevertheless affirmed the safety and importance of the vaccine.
The district court judge in Maryland wrote in April 1991, ". . . the scientists who established and implemented the OPV program were (and are) extraordinarily able professionals who consistently acted in the public interest as they reasonably perceived it to be. They made judgments on extremely difficult questions which, strictly from the standpoint of public health, appear to have been entirely proper."
MMR
The MMR vaccine protects against measles, mumps and rubella (German measles).
Measles is a highly contagious disease that causes high fever, cough, and a spotty rash. Possible complications include ear infections and pneumonia as well. More rarely, measles can infect the brain, causing convulsions, hearing loss, mental retardation, and even death. Babies under 2 and adults get much sicker with measles than do elementary school children.
The MMR vaccine is given in two doses, at 12 to 15 months and again between 4 and 6 years or before junior high or middle school. Most children have no side effects from the MMR vaccine, but about 5 to 15 percent develop a fever. A few develop a measles-like rash, swelling of the lymph glands, and mild pain in the joints.
Mumps is known for causing painful, swollen salivary glands under the jaw, as well as fever and headache. Mumps can be a very serious disease, causing meningitis or hearing loss. Teenage and adult males who get mumps may have painful swelling of the testicles for several days, although no infertility problems later. They get much sicker and suffer longer than children do with the disease.
Rubella is also called German measles. It's a mild disease in children, but rubella endangers the fetus when a pregnant woman catches it. As many as half of the women who contract rubella while pregnant, especially during the first three months, miscarry or deliver babies with heart disease, blindness, hearing loss, or learning problems. Before the rubella vaccine was approved in 1969, some 20,000 babies were born with severe birth defects because their mothers were exposed to the disease while pregnant.
Women with no proof of rubella immunity are routinely tested and should receive the vaccine before getting pregnant. Pregnant women should not receive the rubella vaccine, nor should a woman get pregnant within three months after getting the vaccine because of the potential for endangering the fetus.
Chickenpox
An estimated 3.7 million Americans get chickenpox each year, with more than 90 percent of cases in people younger than 15.
Although chickenpox is generally mild and not normally life-threatening, CDC estimates that there are 9,300 chickenpox-related hospitalizations and 50 to 100 deaths annually, half among young children.
On March 17, 1995, FDA licensed a new vaccine, Varivax (varicella virus vaccine live). Commonly known as the chickenpox vaccine, it will prevent the typical cases of itchy, uncomfortable, week-long rashes and mild fevers, and the rarer cases of serious illness caused by the virus.
Before receiving approval from FDA, researchers tested Varivax in about 11,000 children and adults. Scientists predict that it will be 70 to 90 percent effective in preventing the disease. Of those who did get chickenpox after vaccination, almost all had a mild form of the disease.
Adverse reactions to the vaccine were generally mild and included pain, rash, hardness, and swelling at the injection site, fever, and generalized rashes.
On April 10, 1995, the American Academy of Pediatrics recommended the vaccine for all healthy children between 12 months and 13 years who have not had chickenpox. For children between 12 and 18 months, the academy recommends giving the vaccine at the same time as the first measles, mumps and rubella shot. Older children should be vaccinated at the earliest convenient time.
A single injection of the vaccine is recommended for children ages 12 months to 12 years, while two injections four to eight weeks apart are recommended for adolescents and adults who have never had chickenpox.
"We're not really sure why teens and adults don't get immunity with one shot," says Krause. "The immune response to a single shot if you're 13 or older is not nearly as good as it is if you're younger. But two shots provide immune responses comparable to what younger people get."
For children, the vaccine has been shown to be safe and effective and can be administered at the same time as the measles, mumps and rubella vaccine. (The MMR vaccine is given at 12 to 15 months and again between 4 and 6 years or before junior high or middle school.) Public health officials hope that being able to give the chickenpox vaccine along with an already schedulated vaccine will encourage vaccination.
A new vaccine approved by FDA in September 1998 protects children against rotavirus, the most common cause of severe diarrhea and dehydration in infants and toddlers. According to the DHHS, rotavirus kills an estimated 870,000 children annually, and hospitalizes about 55,000 infants and children.
The government recommended schedule for this oral vaccine is 2, 4, and 6 months. This vaccine may be given concurrently with other vaccines, but it is not recommended for children over 6 months old.
Despite occasional serious reactions from vaccines, for the vast majority of children, benefits of immunity greatly outweigh the risks.
Before any vaccine is licensed by FDA, it has been tested and evaluated thoroughly both in the laboratory and in clinical trials. Besides reviewing scientific studies on vaccines before licensing them, the agency is involved in basic research leading to the development of new and safer products. The acellular pertussis vaccine, for example, was developed in part based on research by FDA scientists.
Agency scientists have developed methods to test vaccines in the laboratory before using them on children. They have also developed accurate methods for testing those children to see if they have appropriate immune responses to new vaccines.
FDA continues to encourage the timely inoculation of all children in this country against childhood diseases, and to make sure those vaccines are as safe and effective as possible.
The act established the National Vaccine Injury Compensation Program to compensate those who suffer certain vaccine-related injuries or death. The act also required health-care providers and manufacturers of specified vaccines to report certain serious adverse reactions they encounter. FDA and CDC keep track of these reports through the Vaccine Adverse Event Reporting System, or VAERS.
VAERS tracks serious vaccine reactions, not common fevers and soreness from shots. Serious reactions include death, life-threatening illness, hospitalization, and disability resulting from a vaccine. Patient identity is kept confidential.
Monthly reports from VAERS are sent to FDA's Center for Biologics Evaluation and Research, which evaluates possible safety issues. Anyone may file a report. To receive a VAERS reporting form, call (1-800) 822-7967.
From its beginning to September 1993, VAERS received more than 20,000 reports. Though it helps in assessing the number of adverse reactions to vaccines nationwide, VAERS is a "passive" system that relies on reporting from health-care professionals and others. For instance, VAERS does not directly compare the incidence of disease among recently vaccinated people with disease among people who have not been vaccinated.
The National Vaccine Injury Compensation Program protects doctors and manufacturers from lawsuits while providing compensation for those injured from vaccines. It's designed to be easier and faster than traditional legal remedies for medical injuries.
Individuals claiming more than $1,000 in expenses from vaccine injury may be eligible for as much as $250,000 compensation. Any death from a vaccine is awarded the highest amount in compensation.
Some injuries may be compensated without proof that the vaccine was at fault. These are spelled out in a vaccine injury table. Most injuries must occur within hours or days of a vaccine to be considered a result of the shot. For more information about what injuries may be compensated, call (1-800) 338-2382.
Publication No. (FDA) 98-9011
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