Immunizations

Topic Overview

What are immunizations?

Immunizations save lives. They are the best way to help protect you or your child from certain infectious diseases. They also help reduce the spread of disease to others and prevent epidemics. Most are given as shots. They are sometimes called vaccines, or vaccinations.

In many cases when you get a vaccine, you get a tiny amount of a weakened or dead form of the organism that causes the disease. This amount is not enough to give you the actual disease. But it is enough to cause your immune system to make antibodies that can recognize and attack the organism if you are ever exposed to it.

Sometimes a vaccine does not completely prevent the disease, but it will make the disease much less serious if you do get it.

Some immunizations are needed only one time. Others require several doses over time to help your body be able to fight the disease (build immunity).

What are some reasons to get immunized?

• Immunizations protect you or your child from dangerous diseases.
• They help reduce the spread of disease to others.
• They are often needed for entrance into school or day care. And they may be needed for employment or for travel to another country.
• Getting immunized costs less than getting treated for the diseases that the shots protect you from.
• The risk of getting a disease is much greater than the risk of having a serious reaction to the vaccine.
• When immunization rates drop below a certain level, preventable diseases show up again. Often, these diseases are hard to treat. For example, measles outbreaks still occur in the U.S.

If you are a woman who is planning to get pregnant, talk to your doctor about what immunizations you have had and what you may need to protect your baby. And if you live with a pregnant woman, make sure your vaccines are up-to-date.

Traveling to other countries may be another reason to get immunized. Talk with your doctor months before you leave, to see if you need any shots.

What immunizations are recommended for children and adolescents?

Ask your doctor what shots your child should get. The immunization schedule includes vaccines for:

• Bacterial meningitis.
• Chickenpox.
• Diphtheria, tetanus, and pertussis (also known as whooping cough).
• Flu (influenza).
• Haemophilus influenzae type b disease, or Hib disease.
• Hepatitis A.
• Hepatitis B.
• Human papillomavirus (HPV).
• Measles, mumps, and rubella.
• Pneumococcal disease.
• Polio.
• Rotavirus.

Immunizations start right after birth, and many are given throughout a baby's first 23 months. Booster shots (the later doses of any vaccines that need to be repeated over time) occur throughout life.

Fewer immunizations are needed after age 6. But older children and teens need shots too (such as those for bacterial meningitis and for tetanus, diphtheria, and whooping cough). Some shots are also given during adulthood (such as a tetanus shot).

It is important to keep a good record, including a list of any reactions to the vaccines. When you enroll your child in day care or school, you may need to show proof of immunizations. Your child may also need the record later in life for college, employment, or travel.

Talk to your doctor if you or your child plans to be in a group living situation, like a college dormitory or summer camp. You may want certain shots, like those for meningitis.

What vaccines are recommended for adults?

The vaccines you need as an adult depend not only on your age, lifestyle, overall health, pregnancy status, and travel plans but also on who you are in close contact with and what vaccines you had as a child.

Talk to your doctor about which vaccines you need. Common adult vaccines include:

• Flu.
• Human papillomavirus (HPV).
• Pneumococcal.
• Shingles.
• Tetanus, diphtheria, and pertussis.

In some states, pharmacists can give some of these shots.

What are the side effects of vaccines?

Most side effects from vaccines are minor, if they occur at all. Ask your doctor or pharmacist about the reactions that could occur. They may include:

• Redness, mild swelling, or soreness where the shot was given.
• A slight fever.
• Drowsiness, crankiness, and poor appetite.
• A mild rash 7 to 14 days after chickenpox or measles-mumps-rubella shots.
• Temporary joint pain after a measles-mumps-rubella shot.

Serious reactions, such as trouble breathing or a high fever are rare. If you or your child has an unusual reaction, call your doctor.

How safe are vaccines?

False claims in the news have made some parents concerned about a link between autism and the shot for measles, mumps, and rubella. But studies have found no link between vaccines and autism.^{footnote 1, footnote 2}

Some parents question whether mercury-containing thimerosal (used as a preservative in vaccines) might cause autism. Studies have not found a link between thimerosal-containing vaccines and autism.^{footnote 3} Today, all routine childhood vaccines made for the U.S. contain either no thimerosal or only trace amounts.^{footnote 4}

Two major government agencies, along with vaccine makers and other groups, watch for, study, and keep track of adverse events that occur after vaccines are given.

Frequently Asked Questions

Childhood Immunizations

Recommended immunizations

The U.S. Advisory Committee on Immunization Practices (ACIP), the American Academy of Pediatrics, and the American Academy of Family Physicians recommend a specific childhood immunization schedule each year. Immunizations are recommended, because they protect against diseases (give immunity) or make a disease less severe if your child does get it. The schedule outlines the immunizations and booster shots needed from birth through age 18, as well as when catch-up immunizations should be given.

The schedule for a premature infant is the same as for a full-term infant. But sometimes the hepatitis B vaccine is delayed.

Many immunizations require more than one dose, given at varying intervals. Although your child does not need to restart the series if a scheduled dose is missed, the immunization should be given as soon as possible.

Immunizations recommended for children younger than 11 years of age include:^{footnote 5}

Chickenpox (varicella)

This shot (called Varivax) protects against chickenpox.

Who should get it?

• Two doses are given to all children 12 months of age and older who have not had chickenpox-one at age 12 to 15 months and one at age 4 to 6 years.

The combination MMRV (ProQuad) shot can be given in place of Varivax. The vaccines for chickenpox, measles, mumps, and rubella are all in this one shot.

Diphtheria, tetanus, and pertussis (DTaP)

This shot (immunization) protects against diphtheria, tetanus, and whooping cough (pertussis).

Who should get it?

• Five doses are given to all children-one at age 2 months, one at 4 months, one at 6 months, one at 15 to 18 months, and one at 4 to 6 years.

Flu (influenza)

This immunization helps protect against the flu. Flu viruses are always changing, so the flu vaccines are updated every year.

Who should get it?

• All people ages 6 months and older need one dose each year. Children younger than 9 years of age may need two doses depending on when they started getting this yearly immunization.

A nasal spray flu vaccine was available in previous years. At times, the nasal spray did not work as well as the flu shot. The nasal spray vaccine is not available right now. For the most current CDC guidelines about the flu, go to www.cdc.gov/flu.

Haemophilus influenzae type b (Hib)

This shot protects against bacteria that can cause an infection in the lungs (pneumonia) or the covering of the brain (meningitis), skin and bone infections, and other serious illnesses in young children. It does not protect against viral influenza (flu).

Who should get it?

• All children need three or four doses, starting at 2 months of age and ending by 15 months of age.
• Children who are older than 5 years and have certain health conditions may also need this shot.

Hepatitis A (Hep A)

This shot protects against hepatitis A disease.

Who should get it?

• All children starting at 1 year of age need two doses, given at least 6 months apart.
• Anyone who will be in close contact with an adopted child from a country that has high rates of hepatitis A needs two doses. This includes household contacts and babysitters. This recommendation only applies for the first 60 days the child is in the United States.^{footnote 6}

Hepatitis B (Hep B)

This shot protects against hepatitis B disease.

Who should get it?

• All children need at least three doses. The first dose is given right after birth, before the child leaves the hospital. The remaining doses are given by 6 to 18 months of age.

Measles, mumps, and rubella (MMR)

This shot protects against measles, mumps, and rubella.

Who should get it?

• Two doses are given to all children-one at age 12 to 15 months and one at age 4 to 6 years.

There is a measles, mumps, rubella, and varicella (MMRV, or ProQuad) shot that also protects against chickenpox (varicella). Talk to your child's doctor about the pros and cons of the MMRV shot. It can be given to children ages 12 months to 12 years.

Pneumococcal infections

This shot (called PCV13, or Prevnar13) protects against a bacteria that causes meningitis, blood infections (sepsis), and ear infections.

Who should get it?

• All children need four doses-one at age 2 months, one at 4 months, one at 6 months, and one at 12 to 15 months.

Polio

This shot protects against polio.

Who should get it?

• Four doses are given to all children-one at age 2 months, one at 4 months, one at 6 to 18 months, and one at 4 to 6 years.

Rotavirus (Rotarix or RotaTeq)

This immunization protects against rotavirus infection, which causes severe diarrhea.

Who should get it?

• Three doses of RotaTeq are given to all children-one at age 2 months, one at 4 months, and one at 6 months. If your child gets Rotarix, two doses are given-one at age 2 months and one at 4 months.

This immunization is swallowed rather than given as a shot. Without this vaccine, most children will get infected by the time they are about 5 years old.

Other immunizations

Your child's doctor may suggest other shots if your child is at higher risk than other children for certain health problems. These may include:

Meningococcal conjugate

This shot protects against a bacteria that causes meningitis and blood infections (sepsis).

Who should get it?

• Children who have a higher risk than other children for getting and having severe problems from meningitis need at least two shots. This includes children ages 2 months and older who have certain immune system problems, children who have a damaged or missing spleen, and children who live in or will travel to areas of the world where the disease is common.

Children who remain at high risk need routine booster shots starting a few years after their first doses of meningococcal conjugate shots. Ask your doctor if your child has a high risk of getting infections from bacterial meningitis and whether booster shots are needed.

Pneumococcal polysaccharide (PPSV, or Pneumovax 23)

This shot does not necessarily reduce the risk of getting pneumonia. But it can prevent some of the serious complications of pneumonia, such as blood infections (sepsis).

Who should get it?

• Children ages 2 years and older who have certain chronic diseases, such as diabetes or heart disease, need this shot at age 2 or as soon as possible after it is known that they have a chronic illness. This shot is usually given after the PCV series is finished.

Combination vaccines

Combination vaccines are usually preferred to separate shots because they reduce the number of needle pricks.

Keeping good immunization records

It is important to keep accurate records (What is a PDF document?) of immunizations, including any reactions to the vaccines. When you enroll your child in day care or school, you may need to show proof of immunizations. Also, your child may need the record later in life for college, employment, or travel.

• Know when each immunization should be scheduled, and put reminder notes on your calendar. You also may want to ask your doctor to send you notices when immunizations are due.
• Have your doctor go over your child's immunization record with you during each office visit.
• Keep the record in a safe place, and never throw it away. It is an important part of your child's lifelong medical records.

Immunization safety

You may worry that immunizations are dangerous if given when your child has a cold or other minor illness. Talk to your child's doctor if you have concerns about the timing of immunizations. Immunizations can usually still be given during a mild illness, while medicines are being taken, and in other situations where a child may not be in perfect health. Also, getting several vaccines at the same time is as safe as getting one shot at a time.^{footnote 7} There are very few reasons for which doctors suggest that a person postpone or not get an immunization.

Some parents fear that the measles-mumps-rubella (MMR) vaccine may cause their child to develop autism. Misleading stories about the MMR shot and autism have circulated through websites, the media, and word of mouth. But scientific studies have found no connection between autism and the vaccine.^{footnote 1}

For more information about vaccine safety studies and vaccine side effects, see the topic Immunization Safety.

Adolescent Immunizations

Recommended immunizations

Adolescents need certain immunizations and booster shots for ongoing protection (immunity) against diseases. Consult your doctor or public health department if your child missed an immunization or if you need to find out whether your child needs a certain one.

The U.S. Advisory Committee on Immunization Practices (ACIP), the American Academy of Pediatrics, and the American Academy of Family Physicians recommend a specific immunization schedule for children and adolescents each year.^{footnote 5} This schedule outlines the immunizations and booster shots needed during adolescence and also when catch-up immunizations should be given.

Immunizations recommended include:

Flu (influenza)

This immunization helps protect against the flu. Flu viruses are always changing, so the flu vaccines are updated every year. Protection lasts up to a year for each flu vaccine type.

Who should get it?

• All people ages 6 months and older need one dose each year.

People ages 18 to 64 can get the intradermal flu shot instead of the regular flu shot. The intradermal vaccine gets injected into the skin instead of the muscle. And it uses a much smaller needle than the regular flu shot. A nasal spray flu vaccine was available in previous years. At times, the nasal spray did not work as well as the flu shot. The nasal spray vaccine is not available right now.

For the most current CDC guidelines about the flu, go to www.cdc.gov/flu.

Human papillomavirus (HPV)

The HPV (human papillomavirus) vaccine protects against HPV. HPV is a common sexually transmitted infection (STI). There are many types of HPV. Some types of the virus can cause genital warts. Other types can cause cervical or oral cancer and some uncommon cancers, such as vaginal and anal cancer. The HPV vaccine protects against the most common HPV types that can cause serious problems.

Who should get it?

• It is recommended that girls and boys age 11 or 12 get the HPV vaccine, but the vaccine can be given from age 9 to 26.
• Children ages 9 to 14 get the vaccine in a series of two shots over 6 months. Children age 15 years and older should get the vaccine as a three-dose series. For the vaccine to work best, all shots in the series must be given.

If your child already has HPV infection, talk with your doctor about whether to get your child immunized. The shot has not been shown to help existing HPV infection, but it may protect your child from other HPV infections.

HPV: Should My Child Get the Vaccine?

Meningococcal conjugate (Menactra or Menveo)

This shot protects against a bacteria that causes meningitis and blood infections (sepsis).

Who should get it?

• All adolescents need two doses, one at age 11 or 12 and one at age 16.
• Teens and young adults ages 13 to 21 who haven't had this vaccine should get it as soon as possible. This includes college freshmen who live in dormitories.

People who have a damaged or missing spleen or who have certain immune system problems need a booster dose every 5 years.

Tetanus, diphtheria, and pertussis (Tdap)

This booster shot protects against tetanus, diphtheria, and whooping cough (pertussis).

Who should get it?

• All preteens ages 11 or 12 need one Tdap shot.
• All teens who haven't had the shot should get it as soon as possible.

Other immunizations

Some adolescents may need or want additional immunizations for situations that increase a person's risk for exposure to disease, such as being in group living situations (when attending college or summer camp) or traveling to other countries. They may have missed shots when they were younger. Or a vaccine may not have been offered when they were younger. These immunizations may include:

Chickenpox (varicella)

This is important if your child never had chickenpox or never got this shot.

This shot (called Varivax) protects against chickenpox.

Who should get it?

• Adolescents and adults who are not already immune to the chickenpox virus need this shot. Anyone who gets this shot at age 13 or older should get two doses at least 4 weeks apart.

Chickenpox infection can be very serious when it occurs after childhood.

Hepatitis A (Hep A)

This shot protects against hepatitis A disease. Two doses are needed over at least 6 months.

Who should get it?

• Adolescents may need this shot if they did not get it as a child. Talk to your child's doctor if your child never got this shot.
• Some states and communities have set up routine immunization because hepatitis A occurs there more often than in other areas. Adolescents living in these areas need this shot.
• Adolescents in communities where outbreaks of hepatitis A are happening may need this shot.
• Anyone 1 year of age and older who is traveling to certain foreign countries also needs this shot.
• Anyone who will be in close contact with an adopted child from a country that has high rates of hepatitis A needs this shot. This includes household contacts and babysitters. This recommendation only applies for the first 60 days the child is in the United States.^{footnote 6}

Hepatitis B (Hep B)

This is important if your child never got this shot.

This shot protects against hepatitis B disease.

Who should get it?

• Anyone 18 years of age or younger who has not had this shot should get three doses over a period of about 6 months.

Measles, mumps, and rubella (MMR)

This is important if your child never got this shot.

This shot protects against measles, mumps, and rubella. There is a measles, mumps, rubella, and varicella (MMRV, or ProQuad) shot that also protects against chickenpox (varicella). It can be substituted for either or both doses of MMR in children ages 12 months to 12 years.

Who should get it?

• If your child did not get either or both doses, he or she should try to get immunized at age 11 or 12.

Pneumococcal polysaccharide (PPSV, or Pneumovax 23)

This shot does not necessarily reduce the risk of getting pneumonia. But it can prevent some of the serious complications of pneumonia, such as blood infections (sepsis).

Who should get it?

• Adolescents with certain chronic diseases, such as diabetes or heart disease, need this shot.

Immunization safety

Most side effects from vaccines are minor, if they occur at all. The doctor may have your child stay in the office for up to 15 minutes after the shots are given, to watch for any reactions.

You may worry that immunizations are dangerous if they are given when your child has a cold or other minor illness. Talk to your child's doctor if you have concerns about the timing of shots. But keep in mind that shots can usually still be given during a mild illness, while medicines are being taken, and in other situations where a child may not be in perfect health. There are very few reasons for which doctors suggest that a person postpone or not get an immunization.

For more information about vaccine safety studies and vaccine side effects, see the topic Immunization Safety.

Adult Immunizations

Recommended immunizations

Your need for immunizations does not end when you reach adulthood. The specific shots (injections) you need as an adult depend not only on your age, lifestyle, overall health, pregnancy status, and travel plans but also on who you are in close contact with and what vaccines you had as a child. Tetanus and diphtheria shots need to be repeated every 10 years throughout adulthood in order to keep your immunity.

Each year the U.S. Advisory Committee on Immunization Practices (ACIP), the American College of Obstetrics and Gynecologists, the American College of Physicians, the American Academy of Family Physicians, and the American College of Nurse-Midwives recommend a specific adult immunization schedule (What is a PDF document?). Your doctor will consider your medical and immunization history (and documentation) when deciding which shots you need.

Immunizations given during adulthood may include:^{footnote 8}

Flu (influenza)

This immunization helps protect against the flu. Flu viruses are always changing, so the flu vaccines are updated every year. Protection lasts up to a year for each flu vaccine type.

Who should get it?

• All adults need one dose each year. It is especially important for:
  • People at higher risk of severe flu.
  • Close contacts of people who are at higher risk, including people who live with or care for children younger than 6 months.

People ages 18 to 64 can get the intradermal flu shot instead of the regular flu shot. The intradermal vaccine gets injected into the skin instead of the muscle. And it uses a much smaller needle than the regular flu shot. A nasal spray flu vaccine was available in previous years. At times, the nasal spray did not work as well as the flu shot. The nasal spray vaccine is not available right now.

Adults ages 65 and older can get a high-dose flu shot.^{footnote 9} Studies are being done to see if the high-dose shot protects older adults better than the standard-dose shot.

For the most current CDC guidelines about the flu, go to www.cdc.gov/flu.

Flu Vaccines: Should I Get a Flu Vaccine?

Flu Vaccine Myths

Hepatitis A (Hep A)

This shot protects against hepatitis A disease.

Who should get it?

• Anyone who will be in close contact with an adopted child from a country that has high rates of hepatitis A needs two doses. This includes household contacts and babysitters. This recommendation only applies for the first 60 days the child is in the United States.^{footnote 6}
• Adults who will be traveling to certain foreign countries need two doses given at least 6 months apart.
• Adults who have certain risk factors, such as long-term (chronic) liver disease, also need two doses.

Hepatitis B (Hep B)

This shot protects against hepatitis B disease. Three doses are needed over at least 4 months.

Who should get it?

Adults who have not had this vaccine series need this shot when occupation, travel, health condition, or lifestyle increases their risk of exposure.

A hepatitis combination vaccine (Twinrix) is recommended for those who are at risk for both hepatitis A and hepatitis B. This vaccine is approved in the United States only for those 18 years of age or older.

Pneumococcal

This shot does not necessarily reduce your risk of getting pneumonia, but it can prevent some of the serious complications of pneumonia, such as infection in the bloodstream (bacteremia) or throughout the body (septicemia).

Your doctor can help you choose between the pneumococcal polysaccharide vaccine (Pneumovax, or PPSV) or the pneumococcal conjugate vaccine (Prevnar, or PCV).

Who should get it?

• People ages 65 years and older need both PCV and PPSV.
• People who are at high risk for pneumococcal infection usually need more than one dose. For example:
  • People ages 2 years to 64 years who have a chronic disease (such as diabetes or heart, lung, or liver disease) need PPSV.
  • People ages 19 to 64 years who have asthma or who smoke cigarettes need PPSV.
  • People ages 19 and older who have immune system problems, cerebrospinal fluid leaks, cochlear implants, no spleen, or a damaged spleen need both PCV and PPSV.

Shingles (herpes zoster)

There are two types of vaccines, Shingrix (RZV) and Zostavax (ZVL), to protect against shingles.

Who should get a shingles vaccine?

• Adults age 50 and older need two doses, 2 to 6 months apart of RZV, whether or not they have had shingles or the ZVL vaccine before.
• Adults ages 60 and older need one dose of ZVL.

Ask your doctor or pharmacist which shingles vaccine is right for you.

Shingles: Should I Get a Shot to Prevent Shingles?

Tetanus and diphtheria (Td) or Tetanus, diphtheria, and pertussis (Tdap)

The Tdap shot protects against tetanus, diphtheria, and whooping cough (pertussis). The Td shot does not protect against pertussis.

Who should get it?

• All adults need Td booster shots every 10 years throughout life.
• All adults need one shot of Tdap in place of a Td shot.
• All pregnant women need a Tdap shot during each pregnancy.

It's important to get the Tdap shot at least 2 weeks before having close contact with a baby.

Other immunizations

You may need or want additional immunizations if certain situations raise your chance for exposure to disease. Or you may have missed shots when you were younger. Or a vaccine may not have been offered when you were younger. These immunizations may include:

Chickenpox (varicella)

This is important if you never had chickenpox or never got this shot.

This shot (called Varivax) protects against chickenpox. Chickenpox infection can be very serious when it occurs after childhood.

Who should get it?

• Adults who are not already immune to the chickenpox virus need two doses, given at least 4 weeks apart.
• Women who don't have evidence of immunity and recently gave birth should get this shot.

Pregnant women and people with immune system problems should not get this shot.

Human papillomavirus (HPV)

This is important if you never got this shot.

The HPV (human papillomavirus) vaccine protects against HPV. HPV is a common sexually transmitted infection (STI). There are many types of HPV. Some types of the virus can cause genital warts. Other types can cause cervical or oral cancer and some uncommon cancers, such as vaginal and anal cancer. The HPV vaccine protects against the most common HPV types that can cause serious problems.

Who should get it?

• It is recommended that girls and boys age 11 or 12 get the HPV vaccine, but the vaccine can be given from age 9 to 26.
• Children ages 9 to 14 get the vaccine in a series of two shots over 6 months. Children age 15 years and older should get the vaccine as a three-dose series. For the vaccine to work best, all shots in the series must be given.

If you already have HPV infection, talk with your doctor about whether to get immunized. The shot has not been shown to help existing HPV infection, but it may protect you from other HPV infections.

Measles, mumps, and rubella (MMR)

This is important if you never got this shot or never had these diseases.

This shot protects against measles, mumps, and rubella.

Who should get it?

• Adults born after 1956 who have not had the MMR vaccine should get at least one dose if they do not have evidence of immunity.

Women should avoid becoming pregnant for 28 days after getting the MMR shot. Women who are known or suspected to be pregnant and people who have impaired immune systems should not get this shot.

Meningococcal (conjugate or polysaccharide, depending on your age)

This shot protects against a bacteria that causes meningitis and blood infections (sepsis).

Who should get it?

• Adults who have a damaged or missing spleen or who have certain immune system problems need two initial doses and then a booster dose every 5 years.
• Adults who have a higher risk than others for getting and having severe problems from meningitis need one shot. This includes adults who will travel or live in areas of the world where the disease is common.

For adults up to age 55, the meningococcal conjugate vaccine (MCV) is usually given. Adults older than age 55 are immunized with the meningococcal polysaccharide (MPSV4) vaccine, called Menomune. Some people may need booster shots.

Polio (IPV)

This shot protects against polio.

Who should get it?

• Adults whose travel or job puts them at increased risk for exposure to polio need three doses of this shot.
• Adults who never had the full series of oral polio vaccine (OPV) or inactivated polio vaccine (IPV) and who have an increased risk of being exposed to polio need the shots they missed.

Routine polio immunization is not recommended for adults (ages 18 and older) who live in the United States.

Consult your doctor or public health department if you missed an immunization or to find out whether you need a specific immunization. For more information about each vaccine, see the topic Vaccine Information Statements.

Immunizations and pregnancy

Before you become pregnant, discuss your immunization history with your doctor. Your immunity protects both you and your baby. Some vaccines (such as the ones for flu and Tdap) can be given during pregnancy. Some vaccines need to be given before or soon after pregnancy.

If you are pregnant, your children should still get their immunizations on schedule. You do not need to speed up or delay your other children's immunizations.

Immunization safety

You may worry that immunizations are dangerous if they are given when you have a cold or other minor illness. Talk to your doctor if you have concerns about the timing of shots. But keep in mind that shots can usually still be given during a mild illness, while medicines are being taken, and in other situations where you may not be in perfect health. There are very few reasons for which doctors suggest that a person postpone or not get an immunization.

For more information about vaccine safety studies and vaccine side effects, see the topic Immunization Safety.

Travel Immunizations

Recommended immunizations

Talk with your doctor months in advance of a trip to find out whether any immunizations are recommended. Certain things, such as your age and health, where you are going, and the length of your stay, affect your risk of disease and your need for immunization.

Your age and health

People with certain medical conditions, such as immune system problems, may have different immunization recommendations than healthy people. Also, young children who are traveling may need to receive their routine immunizations sooner than normally scheduled.

Where you travel

In most developed countries (including Canada, Australia, New Zealand, Japan, and western and northern European countries), the risk of exposure to serious diseases is generally no greater than it is in the United States.

The risk of exposure to serious disease may be much higher in developing countries (such as those in most parts of Africa and Asia and many parts of South and Central America) than it is in most developed countries. This is especially true for areas with poor sanitation (for example, poor water and food handling). For example:

• If you are going to travel to South America or Africa, you may need the yellow fever vaccine.
• Travelers to developing countries should take precautions to prevent hepatitis A infection, which may include getting immunized. Additional immunizations, such as typhoid vaccine, may be recommended.

The need for travel immunizations depends on your immunization history, the specific area you plan to visit, the time of year, and whether any outbreaks of disease have recently occurred.

How you travel and types of activities

Certain activities or modes of travel increase your risk of exposure to disease. These include:

• Exploring rural areas or those off the usual tourist route.
• Taking backpacking trips.
• Visiting people in another country.

Length of stay

The longer you stay in a country, the more exposure you have to local pathogens that could cause harm.

More information

You can get information about travel immunizations by:

• Contacting your local health department or doctor.
• Visiting the website of the Centers for Disease Control and Prevention (CDC) at www.cdc.gov/travel.

For more information on immunizations and health related to travel, see the topic Travel Health.

Bioterrorism and Immunizations

The United States government has developed plans on how to respond to possible bioterrorism threats.

A 2007 law called the Pandemic and All-Hazards Preparedness Act ("Bioshield II") will help companies make more vaccines and drugs that protect against bioterror agents.^{footnote 10}

Certain diseases have been identified that pose the greatest threat to the U.S. public. At this time, there is a supply of anthrax and smallpox vaccines only. These immunizations are not currently available to or recommended for the general public. But the government has advised immunization for people at high risk of exposure to anthrax or smallpox, such as health care workers specifically designated to respond to a bioterrorism emergency. Some of these recommendations are listed below.

This shot protects against anthrax.

Who should get it?

• This shot is for people at high risk of exposure, such as certain lab workers, people who work with imported animals where preventive standards are lacking (such as veterinarians who travel to work in other countries), and certain military members.

Five shots are given over 18 months. And booster shots are needed every year for continued protection (immunity).

This shot protects against smallpox.

Who should get it?

• This shot is for certain health care and public health workers, infection-control specialists, and certain military members.

This shot is given once as several quick punctures on the upper arm, using a special prong device. Immunity after a first-time immunization is likely to be 3 to 5 years. If you have been immunized in the past, successful revaccination may extend your immunity.

The United States has enough smallpox vaccine to vaccinate Americans in an emergency.^{footnote 11}

More information about these immunization recommendations can be found on the Centers for Disease Control and Prevention (CDC) website at www.bt.cdc.gov/bioterrorism. For general information about bioterrorism issues, see the topic Terrorism and Other Public Health Threats.

When to Call a Doctor

Call 911 or other emergency services if you or your child develops any of the following symptoms:

• An allergic reaction, such as difficulty breathing, wheezing, hives, hoarseness, paleness, weakness, a fast heart rate, or dizziness.
• Behavior changes, such as passing out (losing consciousness), acting confused, being very sleepy or hard to wake up, or not responding to being touched or talked to.
• A seizure.

Call your doctor if:

• Redness and swelling at the site of the shot (injection) last longer than 48 hours.
• Your child is 3 months of age or younger and has a fever of 100.4°F (38°C) or higher.
• A fever lasts longer than a few days after receiving a shot.
• Any unusual reaction occurs.

If a fever develops after an immunization and you need to find out if you should call your doctor, see:

• Fever or Chills, Age 11 and Younger.
• Fever or Chills, Age 12 and Older.

Talk with your doctor about whether you need special immunizations because you:

• Are in close contact with people who have an infectious disease.
• Have planned international travel, especially to developing countries.
• Live with or visit a pregnant woman or baby.
• Live with someone who has an impaired immune system.

Home Treatment

Help your child handle immunizations

Many immunizations are given as shots (injections). Your child may experience brief pain as the needle penetrates the skin or muscle. Some vaccines cause more discomfort than others. In general, you can help decrease your child's discomfort by making sure that he or she is physically comfortable and well rested before getting immunized. You can use home treatment measures to help relieve some of the common minor reactions to immunizations.

Relieve mild reactions to immunizations

You can help relieve some of the common, temporary, mild reactions to immunizations with basic home care.

• Fever. A slight fever may occur after you or your child gets a shot. Acetaminophen (such as Tylenol) or ibuprofen (such as Advil) may help lower a fever. Follow the package instructions carefully. If you give medicine to your baby, follow your doctor's advice about what amount to give. Check with your doctor first if you are not sure your young baby's fever is related to getting immunizations. Do not give aspirin to anyone younger than 20 because of the risk of Reye syndrome, a rare but serious disease. For more information on fevers, see the topic Fever or Chills, Age 11 and Younger or Fever or Chills, Age 12 and Older.
• Swelling or redness. The area around the injection site may become red and swollen. Apply a wrapped ice pack or cool compress to the area for about 10 to 20 minutes. If this does not reduce the symptoms, acetaminophen or ibuprofen may help relieve the discomfort. Follow the package instructions carefully.
• Fretfulness and poor appetite. For a few hours after getting immunized, a baby may be fretful and drowsy and may refuse to eat. Plan quiet activities at home for the evening after your child receives an immunization. Hold and cuddle your child when needed. Keep your home at a comfortable temperature, because your child is more likely to be fretful if he or she gets too warm.
• Skin rash. A mild skin rash may arise 7 to 14 days after your child gets the chickenpox or measles, mumps, and rubella (MMR) shot. These types of rashes can last several days and go away without treatment.

For more information about reactions to immunizations, see When to Call a Doctor.