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Guide to Vaccines


Children today are immunized against 16 diseases, including hepatitis A and B, diphtheria, tetanus, pertussis, measles, mumps, rubella, meningitis, pneumonia, polio, chicken pox, flu, H1N1 (swine) flu, rotavirus, and the human papillomavirus (HPV). It can be overwhelming and scary for new parents to try to sort through all of the information -- and misinformation -- out there on the topic of vaccines. Bottom line: Immunizations keep our children safe from deadly diseases, and any risk they may pose is far less than the risk of getting the disease itself.

Vaccine FAQs

Here's an overview of some of the most common questions parents have about vaccines:

Can my child handle so many shots?

Vaccines are made of inactive or very weakened forms of a bacteria or virus. When they enter the body (either orally or through an injection), the immune system responds by creating protective antibodies. These antibodies then live in the body, providing protection against any exposure to the full-force version of the disease.

It's easy to be scared off by the idea of injecting your child with even an extremely weakened or inactive form of an illness. But think of this: The average bacterium that causes a common ear infection is made up of about 3,000 immune components. Every dose of every shot that your child will receive between now and age 8, added together, contain only about 150 immune components, says Dr. Paul Offit, M.D., chief, Division of Infectious Diseases at the Children's Hospital of Philadelphia. Even when your child gets many shots at once, it's still just a tiny amount of the trillions of bacteria that her immune system deals with on a daily basis.

Do these diseases even still exist?

Unlike our parents and grandparents, we're lucky to live in an era that has benefitted from a widely immunized population; we don't see children that are paralyzed by polio or deaf because of the mumps. Many of the shots that our kids receive prevent diseases that many of us haven't even heard of -- diphtheria, anyone?

But when immunization rates drop, these deadly diseases can reemerge. That's because vaccines aren't 100-percent effective; about 95 percent of the protection comes from the vaccine and the remaining protection comes from living in a community where there are low rates of the disease. So for vaccines to keep a disease in check, most people in a community need to be immunized, so they're not contracting and spreading the disease. This way, the few people that are not able to be vaccinated -- say, a child sick with leukemia, or a newborn who hasn't had her shots -- will hopefully be protected by what's called "herd" or "community" immunity.

There are parents who choose not to vaccinate their children based on either religious, philosophical or health objections, and the vaccines that are required to enter daycare or school vary from state to state. Many of these parents argue that their unvaccinated kids can benefit from herd immunity, too. Unfortunately, this isn't a reliable way to protect your child. There have been deadly outbreaks of measles and pertussis in the United States in areas where vaccine rates have fallen. In Eastern Europe and Russia, where immunization has dropped, there have been tens of thousands of cases of diphtheria. For vaccines to work, a community needs to have high rates of immunization. Immunization not only protects your child, but your nieces, nephews, and neighbors, too.

Are vaccines safe?

Without daily reminders of the threat of these diseases, some people have started to fear the vaccines more than the diseases that they prevent. In recent years, a very vocal anti-vaccine movement has emerged, suggesting that vaccines are to blame for everything from allergies to diabetes to asthma to autism. While none of these claims have been proven true, there is still a growing community of scared parents who choose not to vaccinate their children based on this misinformation. In turn, these well-meaning parents end up putting their children at risk, and endangering their community as a whole.

As with any medical intervention, nothing is 100-percent risk free. But when you weigh the risks and benefits, the benefits of protecting your child against deadly diseases far outweigh the very remote risk that the vaccine may cause a reaction. The vast majority of children receiving an immunization will not have any reaction and if they do, it will be a minor one, like redness or soreness at the injection site. Keep reading for a review of the risks of reaction for every vaccine, as well as what you may have heard, and the bottom line as far as safety.

What is thimerosal?

Part of the controversy around vaccines stems from a preservative called thimerosal that was once regularly used in vaccines. Concerns arose because thimerosal is a compound that contains a form of mercury, known as ethylmercury. Another type of mercury, known as methylmercury, can, in large doses (say, from drinking contaminated water or eating large amounts of contaminated fish), harm the brain development of a fetus or child. With the increased number of shots that children receive, some wondered whether children were being exposed to too much of this preservative. In particular, there were concerns that the preservative was to blame for increasing rates of autism, a behavioral disorder that has been on the rise in the U.S. in the past few decades.

As a precautionary measure, thimerosal was removed in 1999 from most vaccines (or reduced to trace amounts), with the exception of the flu vaccine, which is available without the preservative, though you need to request it from your doctor. But it's worth understanding that while the methylmercury found in large fish can build up in the body and harm the developing brain of a growing child, the ethylmercury in thimerosal does not build up in the body. "It's never been linked to any adverse effect," says William Schaffner, M.D., professor of preventive medicine at Vanderbilt University Medical Center, in Nashville, TN. And autism rates in the US have continued to rise even after the preservative was removed from nearly all of the vaccines that children receive. In 2010, a U.S. court ruled that vaccines containing thimerosal cannot cause autism on their own. Read on for more about how the link between thimerosal and autism has been disproven.

Vaccination Schedule

Keep reading to get a detailed run-down of each vaccine, and to find out at which age the various vaccines are generally given. To see the big picture schedule of all vaccines from birth until age 6, check out the Centers for Disease Control and Prevention's immunization schedule, which is updated annually and is also approved by the American Academy of Pediatrics and the American Academy of Family Physicians. There is also a "catch-up" vaccine schedule for a child who may have fallen behind on his shots due to illness, or for an adopted child whose vaccination status is unknown.

In 2010, the vaccine schedule was changed to state that combination shots were generally preferred over single vaccinations. This is because the vaccine schedule includes more shots than it did years ago. Not only does this reduce the number of shots (and tearful episodes), it also insures that your child is vaccinated at the right window of opportunity when she is most vulnerable to the illness. With individual shots, there's that much more of a chance that a missed appointment will leave your child open to exposure.

Combination vaccines also reduce the number of injections that your child needs to receive in order to be protected against all of the disease on the vaccination schedule. The most common combination vaccines are below, though new ones are regularly developed. In addition to the ones that are already on the schedule (MMR, DTaP, PCV), here are some of the most common combination shots. Most do not have an increased rate of a reaction, though some, like the MMRV, have a higher rate of side effects, like fever.

Some parents are concerned about too many immunizations at newborn check-ups, and multiple vaccines administered at the same time. Dr. Bob Sears offers a widely-used alternative schedule that spreads out the shots in The Vaccine Book.

Whatever schedule you decide on, keeping all these shots straight is tough. Stay on top of what immunizations your child gets when with our handy downloadable vaccine tracker.

Hepatitis B (Hep B)

What it prevents: Hepatitis B is a disease caused by the Hepatitis B Virus (HBV) that infects and damages the liver. While it's most commonly transmitted through the exchange of bodily fluids or blood (such as through needle-sharing during drug use, unprotected sex, or a blood transfusion of contaminated blood), or passed from a mom to her baby during delivery, more than 30 percent of those affected have no known risk factors.

When it's given:  Three shots: at birth, 2 months, 6 months. It can be given alone, or as part of a combination shot along with the Hib vaccine.

What you may have heard:  Because Hep B is most commonly transmitted through risk factors like drug use or unprotected sex, some parents wonder why this vaccine would be given to a child at all, let alone to a newborn. The reason: If you're infected as an adult with Hepatitis B, you have a less than 10 percent risk of becoming a chronic Hep B carrier, at high risk for developing liver cancer or severe liver disease, both of which can be fatal. In contrast, more than 90 percent of babies who are affected with Hepatitis B will become chronic Hep B carriers. What's more, more than half of those infected with Hep B do not have any of the common symptoms -- jaundiced (yellowed) eyes and skin, skin rash, nausea, and joint pain -- so it's sometimes impossible to know who is affected. It's estimated that up to 5,000 children in the United States are infected with Hepatitis B each year, and most of these children are born to mothers who are not infected with Hep B.

Risk of a reaction: More than 65 percent of children receiving the vaccine will have no side effects at all. The remaining children may have redness or soreness at the injection site or a slight fever. Very rarely (2 in 100,000) a child may have an allergic reaction (typically those also allergic to baker's yeast), signs of which include difficulty breathing, hives, and a rapid heartbeat. Kids who are allergic to baker's yeast should not receive this vaccine.

Diphtheria, Tetanus, Pertussis (DTaP)

What it prevents: This vaccine prevents against three deadly diseases.

Diphtheria: Caused by a bacterium that usually collects in the throat, the early symptoms are a sore throat, fever, and swollen neck. As the infection progresses, a gray membrane forms (usually in the throat, but it can also occur elsewhere in the body) which can block the airway, making it impossible for the person to breathe. The infection can then spread through the blood causing pneumonia, muscle paralysis, and heart and kidney failure.

Tetanus: Also known as lockjaw, tetanus causes severe continuous muscle spasms throughout the body. An infection results when the bacteria (found in both human and animal feces as well as soil) enters the body through a deep skin wound. It can lead to complications with breathing as well as pneumonia. The CDC states that there are only about 50 cases of tetanus per year in the U.S., but 10-20% of those cases (especially in older patients) result in death.

Pertussis: Also known as whooping cough, pertussis causes severe coughing and may progress to pneumonia and even death.

When it's given:  There are five DTaP shots: The first three are given at ages two months, four months, and six months of age; the fourth is given between 12 and 18 months, and the last is given between four and six years. The first three shots of DTaP can also be given as part of a combination shot with the Hep B and IPV vaccines. A booster shot of Td (tetanus-diphtheria) is needed every 10 years, however, older children (between the ages of 11 and 18) who have received the entire DTaP series should receive a booster that also contains pertussis, known as Tdap.) Parents and caregivers should also receive a Tdap shot to protect newborns from exposure to pertussis (whooping cough) before they are fully immune.

What you may have heard:  An older form of the shot -- the DTP shot, was more likely to cause side effects, such as a fever, because it contained whole cells of the pertussis bacterium. However, the current shot, DTaP, licensed for use by the FDA in 1991, contains only small components of the cell (it's called "acellular" Pertussis), so it's much less likely to cause a reaction.

In the United States, there has been an uptick in cases of pertussis in recent years, because the immunity that the vaccine provides starts to wear off after about ten years. While a teen or an adult can usually fend off a case of pertussis, it can be deadly in a baby. And babies aren't fully protected against pertussis until they've had their third shot at six months. For this reason, the CDC recommends that teens and adults, especially parents and caregivers of babies, receive a booster of the vaccine to protect infants by creating a "cocoon" of immunity.

You also may have heard about outbreaks of diphtheria that have occurred in Russia and Eastern Europe in areas where vaccination levels have fallen. This is a scary reminder of how quickly these diseases can pop up again when vaccine rates start to fall in a community.

Risk of a reaction:  About 50 percent of children receiving the DTaP vaccine will not experience a reaction to the vaccine; the other 50 percent may experience a mild reaction, such as soreness at the injection site, fever, or upset stomach. The last two doses of the DTaP vaccine have on rare occasions been linked to a temporary swelling of the limb where the shot was given.  About 1 percent of children receiving the shot may have a more severe reaction, such as a seizure or a high fever.

Haemophilus influenzae type B (Hib)

What it prevents: Before the Hib shot was on the vaccination schedule, haemophilus influenzae type b was the number one cause of bacterial meningitis, an infection of the fluid around the brain and spinal cord, which can be fatal. This highly contagious bacterium (it can spread through coughing or sneezing) can also cause a swelling of the windpipe and pneumonia, among other deadly infections.

When it's given: Three doses of the Hib vaccine are given: at 2 months, 4 months, and 12 to 15 months of age. Your child can receive it alone, or as part of a combination shot.

What you may have heard: While some people have claimed that there was a link between the Hib vaccine and diabetes, no study has shown any evidence to support a connection.

Risk of a reaction: About 25 percent of kids receiving the shot may have a mild reaction, such as redness, soreness or swelling at site of injection.

Polio (IPV)

What it prevents: Before the IPV vaccine became available in the 1950s, as many as 20,000 people (mostly children) were paralyzed by polio, an infection of the central nervous system, in the US each year; an additional 1,000 people (again, mostly children) died from it. Polio is a highly contagious virus that can be spread through infected saliva or stool, and most people who have it don't show any symptoms. Only a small percentage of people who get polio will become paralyzed (which shows you how widespread it was pre-vaccine to cause paralysis in so many people). Polio has been eradicated from the United States, though it still occurs elsewhere in the world.

When it's given: Inactivated poliovirus IPV is given in four does: 2 months, 4 months, 6 to 18 months, and a booster shot at 4 to 6 years. The shot can be part of a combination shot.

What you may have heard: You may have heard that the polio vaccine can cause polio, but it is impossible for the vaccine now given in the United States -- inactivated polio virus (IPV) -- to give a person polio. What is true: Oral polio virus (OPV), an older form of the vaccine that's used in some countries where polio is still a threat because it can be more effective in a community where polio is still common, can in extremely rare cases (we're talking 1 in 2.4 million people) cause polio; it usually occurs in someone with a weakened immune system.

Risk of a reaction:A child that's allergic to certain antibiotics (streptomycin, polymycin, or neomycin) should not receive the vaccine. If you have a family history of these or other allergies, be sure to let your doctor know. There are no known side effects to IPV other than the mild reaction of redness or soreness at the injection site.

Measles, Mumps, Rubella (MMR)

What it prevents:

Measles: This highly contagious virus (it's spread through coughing or sneezing) causes a cough, runny nose, fever and conjunctivitis, and can also lead to pneumonia and croup. One in 1,000 cases are severe enough to infect the brain, causing permanent damage and even death. There have been dangerous outbreaks of measles recently in the United States, nearly all of them in children who had not been vaccinated.

Mumps: Another highly contagious virus (also spread through coughing and sneezing), mumps causes swelling of the salivary glands. One in 2,000 cases is severe enough to cause permanent deafness.

Rubella: Also known as German measles, rubella is a highly contagious virus (again spread by coughing and sneezing) that causes swelling of the lymph nodes in the neck. In severe cases rubella can cause an infection of the brain or joint pain. Rubella poses the greatest threat to pregnant women because it can cause major birth defects in the fetus, including deafness, blindness, mental retardation and heart defects. Known as congenital rubella syndrome, this condition can also lead to a miscarriage, especially if the mom is infected in her first trimester.

When it's given: The vaccine is given in two doses: one between 12 and 15 months, and the second between four and six years. The MMR vaccine can be given as a single shot or as part of a combination shot together with the Varicella (Chicken Pox) vaccine (known together as MMRV).

What you may have heard: Many of parents' fears about vaccines surround the MMR shot. No doubt if you've ever googled vaccines, you've heard the claims by some that the MMR (or the preservative thimerosal that it used to contain) causes autism, a spectrum of behavioral disorders, rates of which have increased in recent years. This claim persists despite the fact the original research that supported this link (a study of 12 children published in the British Medical Journal The Lancet in 1998) has been retracted by nearly all its authors; The Lancet itself has also retracted it for major ethical violations. Since this research, more than ten studies have examined this link and none have found any connection. The Institute of Medicine, the World Health Organization, and the American Academy of Pediatrics have all stated that the MMR vaccine and thimerosol are not linked to autism. "The possible link between vaccines and autism has been taken very seriously," says Anne Schuchat, director of the National Immunizations Program at the U.S. Centers for Disease Control and Prevention (CDC). "But at this point, after so many studies, it's safe to say these two hypotheses have been eliminated as possible causes."

Risk of a reaction: More than 80 percent of children receiving the shot will not have a reaction. Here are the risks and ranges of reactions, according to the CDC. The risk of contracting measles, mumps, or rubella is far greater than the risk of any of the reactions. 

Mild: 1 in 6 will have a fever; 1 in 20 will have a rash; very rarely, swelling of the glands can occur.

Moderate: 1 in 3,000 may have a febrile seizure (a harmless fever-related seizure that nonetheless is scary for parents); 1 in 30,000 may have a temporary low platelet count. Note that the first dose of the combination shot (MMRV: MMR with Varicella) is associated with a higher risk of rash (1 in 20) and fever (1 in 5). The rate of febrile seizures is also slightly higher for children who receive the MMRV shot.

Severe: 1 in a million may have a serious allergic reaction. Even more rare are conditions that may or may not be associated with the vaccine -- deafness, long-term seizures, and permanent brain damage.

Allergy info: MMR should not be given to a child who has had a life-threatening allergic reaction to gelatin, the antibiotic neomycin, or to a previous dose of MMR. If you have a family history of allergies, be sure to mention it to your doctor.

Pneumococcal conjugate (PCV)

What it prevents: This vaccine protects against several different types of bacteria, known as streptococcus pneumoniae, that usually live harmlessly in your nose and throat. An overgrowth of these pneumococci, however, is one of the most frequent causes of ear infections or more serious (and even deadly) infections in the lungs, blood stream, and central nervous system. Since its introduction in 2000, this vaccine has drastically reduced rates of ear infections and the need for ear tubes in children, as well as the number of more serious pneumococcal infections.

When it's given: PCV is given in four shots: at 2 months, 4 months, 6 months, and between 12 and 15 months.

What you may have heard: The original vaccine used to prevent against the seven most common types of pneumococci (PCV7). In 2010, however, a newer version (PCV13) became available, protecting children against the 13 most common types of the bacteria, making the vaccine even more effective. This is critical, especially since some of these bacteria that the vaccine protects against have become resistant to antibiotic treatment.

Side effects: The vaccine may cause soreness or redness at the injection site, as well as a decrease in appetite and drowsiness. About 20 percent may have a fever over 100.3º F. In extremely rare cases (1 in 10,000) a child may experience a fever-related seizure after the vaccine.


What it prevents: Rotavirus causes fever, diarrhea, extreme vomiting and, in severe cases, can lead to serious dehydration. Before the introduction of this vaccine in 1999, most children were infected with rotavirus before they turned three (it's highly contagious); 1 in 150 were hospitalized because of the infection.

When it's given: There are two different brands of oral Rotavirus vaccine. RotaTeq is given in three doses: 2 months, 4 months, and 6 months.  Rotarix is given in two doses: at 2 months and 4 months. In 2010, the FDA recommended that doctors temporarily stop using Rotarix in order for more studies to be done on it. However, if your child has had this vaccine, don't fret; no children appear to have gotten sick from Rotarix.

Rotavirus is recommended for all full-term babies. Because it hasn't been well-studied in children born earlier than 37 weeks, your doctor will help you decide if your preemie should receive the immunization. More studies are also needed to determine its effectiveness in older babies, so it's currently not recommended to begin the vaccine in children older than 15 weeks old, and the last dose should be given before a child is 8 months. (Rotarix is FDA approved for completion by 24 weeks, or 6 months, of age.)

What you may have heard: There's no evidence that links the rotavirus vaccine to intussusception, a dangerous collapse of the intestines. An earlier form of the vaccine, RotaShield, did increase the risk of this serious condition but is no longer on the market.

Risk of a reaction: It's possible that a baby may occasionally suffer from mild stomach upset (including diarrhea and vomiting) within a week of getting the vaccine. Any reaction should be mild and temporary.

Influenza (Flu Shot)

What it prevents: No doubt you're familiar with the un-fun symptoms of the flu -- fever, sore throat, cough, and body aches -- but you may not realize that this highly contagious virus can occasionally be deadly, killing about 36,000 people each year. This illness can also cause ear infections and pneumonia.

When and how it's given: It's recommended that children ages 6 months to 18 years be vaccinated against the flu once a year, ideally before the November to May flu season. There are two types of flu immunization: an inactivated version (given by injection) and a live version of the vaccine, which contains a weakened, but real form of the flu virus (given as a nasal spray). Children should receive an annual flu shot starting at 6 months of age. Once your child is two, he may be eligible to receive the nasal spray vaccination, assuming that he doesn't have asthma and isn't prone to episodes of wheezing when he's sick. (If he does, he may be eligible for the flu spray after he turns five.) Parents and caregivers of babies should receive an annual flu immunization as well, not only to protect themselves, but also to create a protective "cocoon" of immunity around unvaccinated infants.

What you may have heard: Since the flu virus regularly changes, the vaccine is reformulated each year to try to match the current strains of the flu. However, even if the strains are not an exact match, the vaccine still offers some protection. Many flu shots -- unlike other vaccines --  still use thimerosal as a preservative. While research has disputed any concerns regarding side effects of thimerosal, you can ask your doctor about receiving a thimerosal-free version of the flu shot. The nasal spray does not contain thimerosal.

Risk of a reaction: The flu virus is grown in eggs. Children with a severe egg allergy generally do not receive a flu shot. If your child has an allergy to eggs (or you have a family history of egg allergy), talk to your doctor. Mild side effects of the injection include redness, soreness and swelling at the injection site, as well as mild cold symptoms (cough, fever, aches) that can last one to two days. Mild side effects of the spray include flu-like symptoms such as a cough, runny nose, fever, wheezing or upset stomach.

H1N1 (Swine Flu)

What it prevents: H1N1, also called the swine flu, is a relatively new strain of the influenza virus. Symptoms of the swine flu are pretty much the same as regular flu -- coughing, sneezing, fever, sore throat, and achiness. (And like regular flu, H1N1 can occasionally cause pneumonia and death). The swine flu caused panic when it quickly surfaced and became widespread in 2009 since a new strain means no one in the population has immunity, and it can spread fast. Despite fears, however, it mostly ended up acting like regular old flu. And immunity among the general population is now increased through immunizations and antibodies developed after contracting it.

When and how it's given: Children under nine should receive two doses of the H1N1 vaccine, each about a month apart, at the start of the flu season. Children older than nine can receive just one dose. Children should be vaccinated against H1N1 starting at 6 months of age. Once your child is two, he may be eligible to receive the nasal spray vaccination, assuming that he doesn't have asthma and isn't prone to episodes of wheezing when he's sick. (If he does, he may be eligible for the flu spray after he turns five.)

Like the flu vaccine, there are two types of flu immunization; an inactivated version (given by injection) and a live version of the vaccine, which contains a weakened, but real form of the flu virus (given as a nasal spray).

What you may have heard: The swine flu vaccine was in short supply in 2009, the first year it was available, and it was hard to get advice on whether to get one for your child even if you got your hands on it. In 2010, the CDC added it to the regular vaccine schedule. Some H1N1 shots still use thimerosal as a preservative. If you're concerned about this, you can ask your doctor about receiving a thimerosal-free version of the H1N1 shot. The nasal spray does not contain thimerosal.

Risk of reaction: Like the flu virus, the H1N1 vaccine is grown in eggs. Children with a severe egg allergy generally do not receive a flu shot. If your child has an allergy to eggs (or you have a family history of egg allergy), talk to your doctor. Mild side effects of the injection include redness, soreness and swelling at the injection site as well as a mild cold symptoms (cough, fever, aches) that can last one to two days. Mild side effects of the spray include flu-like symptoms such as a cough, runny nose, fever, wheezing or upset stomach.

Varicella (Varivax)

What it prevents: Varicella, or chicken pox, is caused by the highly-contagious varicella-zoster virus. Symptoms begin with a red rash that blisters and crusts over, putting a child at risk for infection. It is also very itchy and can cause scarring when pox are scratched. In severe cases it can cause a serious infection, pneumonia, and even death. The virus can reemerge later in life and cause the related condition known as shingles.

When it's given: The varicella vaccine is given in two doses. The first is given between 12 and 15 months of age and the second can be given between 4 and 6 years of age but can be given at least three months after the first dosage. Note: Varicella can be given at the same time as the MMR Vaccine (and is available as a combo shot, the MMRV). However, if it is given after the MMR, it must be more than 30 days afterward to maintain maximum effectiveness.

What you may have heard: Been invited to a "chicken pox party?" Some people would rather expose their child to the chicken pox virus naturally rather than by a vaccine, so they intentionally court the virus. Before the advent of the vaccine, this was a common strategy, since chicken pox is a much more serious disease in adults than it is in children. However, the real disease can cause severe risks for infection and even death. The vaccine contains a weakened form of the virus and is much less likely to cause serious side effects.

Risk of a reaction: Most children will have no side effects; 1 in 5 may have a mild reaction such as redness, soreness, or a few chicken-pox-like bumps at the injection site. 1 in 10 may have a fever, and 1 in 25 may have a rash on other parts of the body for up to a month after vaccination. Side effects are a little more common with the combination vaccine: 1 in 5 may have a fever and 1 in 20 may have a rash. Children are also more likely (though it's still rare) to have a febrile seizure with the combination shot.

Hep A

What it prevents: Hepatitis A is a virus that affects the liver and can cause flu-like symptoms, jaundice (a yellowing of the eyes and skin), and death. Children, however, often don't show any symptoms. This highly-contagious virus is spread through contact with contaminated stool or blood; it also can contaminate drinking water or food.

When it's given: Hepatitis A is given in two doses, six months apart, between 12 and 23 months. Hep A can be given alone or as part of a combination shot with Hep B.

What you may have heard: Hepatitis A outbreaks often occur in a community through contaminated food. In recent years, there have been outbreaks in the US stemming from strawberries and green onions in several states. More recently, in 2009, there was a hepatitis A outbreak related to a national fast food chain in Illinois.

Risk of a reaction: Side effects of the vaccine are considered mild. 1 in 6 will experience soreness at the injection site, 1 in 25 will get a headache and 1 in 12 will have a decreased appetite. While very rare, it's possible to have an allergic reaction to a component of the hepatitis A vaccine.


What it prevents: HPV is a group of 40 human papillomaviruses that can be transmitted through sexual contact -- it's estimated by the CDC that at least 50 percent of sexually-active men and women have been infected by the time they're 50. While most infections will go away without treatment, the vaccine protects against the four types of HPV that are most commonly linked to more serious conditions. Types 16 and 18 can cause cervical cancer as well as other types of cancer. Types 6 and 11 cause up to 90 percent of genital warts. Since the vaccine only works if it's given before a person is infected with HPV, it's recommended for girls at 11 to 12, before they become sexually active.

When it's given: The HPV vaccine is given in three doses in girls aged 11 to 12 years old, though it can be given as young as nine years old. The second shot is given two months after the first; the third is given six months after the first.

What you may have heard: There have been several claims that the HPV vaccine can cause different severe reactions. The CDC has not determined that any of these reported conditions can truly be linked to the vaccine. Keep in mind that the vaccine has been tested in more than 11,000 women and found to be safe.

Risk of a reaction: Mild side effects include redness, soreness, itching or swelling at the injection site. One in 10 girls may experience a mild fever. More rarely (1 in 65), a girl may experience a moderate fever.

At the Doctor

It can be hard to sort through fact and fiction when it comes to vaccines, so don't be afraid to address any concerns with your pediatrician. Here are a few questions you might want to ask:

Should my child get vaccinated when she's sick?
If your child has a mild illness, it's usually fine for her to be immunized. With vaccines that contain a live virus, such as the nasal spray version of the flu or H1N1 vaccine (safe for certain children over age two), it's generally recommended that your child be well. Tell your doctor about any symptoms your child may be having before she receives a shot.

What combination shots do you recommend?
Since more vaccines are now recommended, ask your doctor about combo shots, which can mean fewer shots (and fewer tears).

Is there a thimerosol-free version of the vaccine available?
If you have any lingering concerns over the preservative thimerosol, you can ask your doctor if there's a version of the vaccine without it.

Is my child at risk for an allergic reaction?
Talk to your doctor if you have a family history of allergies. Your child will still likely be able to get her vaccines, but your doctor may want you to wait in the office after her shot to be sure that there isn't a reaction. Certain vaccines are not recommended if your child has had a life-threatening allergic reaction to any of the vaccine components or anything used to produce the vaccine. For example, the influenza virus is grown in eggs; children with a severe egg allergy should not receive the vaccine. The MMR shot also contains trace amount of egg, while the HepB vaccine may cause a reaction in children who have an allergy to Baker's Yeast.  If your child does have a severe reaction, head to the emergency room and call your doctor on the way. Later, ask your doctor about filing a report with the Vaccine Adverse Event Reporting System at 1/800-822-7967 or at

Mom's Experience

"I was a wreck over the MMR shot, with so many things linking that to autism, that boys are 40% more likely to have autism, and that 1 in 100 kids have some sort of autism. My doctor and nurse were so great about it. They let me ask as many questions as I wanted, and didn't make me feel like I was crazy, or that I was wrong for questioning things. I did give him the MMR shot, but I separated it." -- Nicole Raczak-Smith, mom to Dakota, age 22 months

"My husband and I decided to spend time interviewing several pediatricians when we were pregnant with our daughter. Every pediatrician said the same thing: 'I vaccinate my kids, so why wouldn't I recommend vaccinating yours?' If I didn't trust my daughter's pediatrician, then all my knowledge is left open to me rifling through all the information out there and of course that can get scary and overwhelming. Our decision to vaccinate was so easy because every pediatrician said the same thing." --  Lisa Hennessey, mom to  Molly, age 12 months

"When I was growing up, I had an elderly aunt who had polio when she was a little girl, and I remember not being able to take my eyes off her wheelchair and shriveled legs. I can't imagine risking that one of my children could get such a terrible illness, so I never dreamed of not vaccinating them."  -- Stephanie Mullen, mom to Charlie, 8

Age-by-age Guide

The classic line about vaccines is that it can be more painful for you than it is for your child. While a shot may hurt, most kids get over it quickly. Though it's hard, try not to show your stress at the doctor's office since children of all ages can pick up on your nonverbal cues.

Here's how to soothe your child at every age:

A half-hour before the appointment (or while you're there), you can give your baby a dose of acetaminophen; check with your doctor about dosing. If you're really worried (or the last shot didn't go so well), you can ask your doctor about using a topical prescription anesthetic cream like EMLA. You'll need to apply it about an hour before the shot. Many infants will cry out during the shot, but recover quickly. During the shot, you can give her a pacifier to suck (a pacifier dipped in sugar water has been shown to reduce pain) or distract her with a toy. Afterwards, nursing or cuddling can help calm her down.

Preschoolers/Older Kids
As your children get older, you'll spend more time dealing with the buildup and anxiety about the shot. You can wait until the day of the appointment to tell your child about her checkup; this way she has less time to worry about it. To ease the pain, you can give a dose of acetaminophen a half-hour before the shot. You can also request a prescription topical anesthetic cream like EMLA that needs to be applied about an hour before the shot. Bringing along a lovey for a younger child or a surprise treat for an older one (M&Ms can have healing powers!) can offer critical distraction post-shot.


To learn more, visit:

The Centers for Disease Control and Prevention

Immunization Info

Every Child By Two