Possible Side-effects from Vaccines

Any vaccine can cause side effects. For the most part these are minor (for example, a sore arm or low-grade fever) and go away within a few days. Listed below are vaccines licensed in the United States and side effects that have been associated with each of them. This information is copied directly from CDC's Vaccine Information Statements, which in turn are derived from the Advisory Committee on Immunization Practices (ACIP) recommendations for each vaccine.

Remember, vaccines are continually monitored for safety, and like any medication, vaccines can cause side effects. However, a decision not to immunize a child also involves risk and could put the child and others who come into contact with him or her at risk of contracting a potentially deadly disease.

Adenovirus vaccine side-effects

What are the risks from Adenovirus vaccine?

A vaccine, like any medicine, could cause a serious reaction. But the risk of a vaccine causing serious harm, or death, is extremely small.

Mild Problems

Several mild problems have been reported within 2 weeks of getting the vaccine:

Severe Problems

More serious problems have been reported by about 1 person in 100, within 6 months of vaccination. These problems included:

It is not clear whether these mild or serious problems were caused by the vaccine or occurred after vaccination by chance.

As with all vaccines, adenovirus vaccine will continue to be monitored for unexpected or severe problems.

Note: Adenovirus vaccine is approved for use only among military personnel.

This information was taken directly from the Adenovirus VIS
(This information taken from Adenovirus VIS dated 7/14/11. If the actual VIS is more recent than this date, the information on this page needs to be updated.)

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Anthrax vaccine side-effects

What are the risks from anthrax vaccine?

Like any medicine, a vaccine could cause a serious problem, such as a severe allergic reaction.

Anthrax is a very serious disease, and the risk of serious harm from the vaccine is extremely small.

Mild Problems

Severe Problems

As with any vaccine, other severe problems have been reported. But these don’t appear to occur any more often among anthrax vaccine recipients than among unvaccinated people.

There is no evidence that anthrax vaccine causes long-term health problems.

Independent civilian committees have not found anthrax vaccination to be a factor in unexplained illnesses among Gulf War veterans.

This information was taken directly from the Anthrax VIS
(This information taken from Anthrax VIS dated 3/10/10. If the actual VIS is more recent than this date, the information on this page needs to be updated.)

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DTaP vaccine side-effects
(Diphtheria, Tetanus, and acellular Pertussis)

What are the risks from DTaP vaccine?

Getting diphtheria, tetanus or pertussis disease is much riskier than getting DTaP vaccine.

However, a vaccine, like any medicine, is capable of causing serious problems, such as severe allergic reactions. The risk of DTaP vaccine causing serious harm, or death, is extremely small.

Mild Problems (Common)

These problems occur more often after the 4th and 5th doses of the DTaP series than after earlier doses.

Sometimes the 4th or 5th dose of DTaP vaccine is followed by swelling of the entire arm or leg in which the shot was given, for 1 to 7 days (up to about 1 child in 30).

Other mild problems include:

These problems generally occur 1 to 3 days after the shot.

Moderate Problems (Uncommon)

Severe Problems (Very Rare)
Serious allergic reaction (less than 1 out of a million doses) Several other severe problems have been reported after DTaP vaccine. These include:

These are so rare it is hard to tell if they are caused by the vaccine.

Controlling fever is especially important for children who have had seizures, for any reason. It is also important if another family member has had seizures.

You can reduce fever and pain by giving your child an aspirin-free pain reliever when the shot is given, and for the next 24 hours, following the package instructions.

This information was taken directly from the DTaP VIS
(This information taken from DTaP VIS dated 5/17/07. If the actual VIS is more recent than this date, the information on this page needs to be updated.)

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Hepatitis A vaccine side-effects

What are the risks from hepatitis A vaccine?

A vaccine, like any medicine, could possibly cause serious problems, such as severe allergic reactions. The risk of hepatitis A vaccine causing serious harm, or death, is extremely small.

Getting hepatitis A vaccine is much safer than getting the disease.

Mild Problems

If these problems occur, they usually last 1 or 2 days

Severe Problems

This information was taken directly from the Hepatitis A VIS
(This information taken from Hepatitis A VIS dated 10/25/11. If the actual VIS is more recent than this date, the information on this page needs to be updated.)

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Hepatitis B vaccine side-effects

What are the risks from hepatitis B vaccine?

Hepatitis B is a very safe vaccine. Most people do not have any problems with it.

The vaccine contains non-infectious material, and cannot cause hepatitis B infection.

Some mild problems have been reported

Severe problems are extremely rare. Severe allergic reactions are believed to occur about once in 1.1 million doses.

A vaccine, like any medicine, could cause a serious reaction. But the risk of a vaccine causing serious harm, or death, is extremely small. More than 100 million people in the United States have been vaccinated with hepatitis B vaccine.

This information was taken directly from the Hepatitis B VIS
(This information taken from Hepatitis B VIS dated 2/2/12. If the actual VIS is more recent than this date, the information on this page needs to be updated.)

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Hib vaccine side-effects

What are the risks from Hib (Haemophilus influenzae type b) vaccine?

With a vaccine, like any medicine, there is a chance of side effects. These are usually mild and go away on their own.

Serious side effects are also possible, but are very rare.

Most people who get Hib vaccine do not have any problems with it.

Mild Problems following Hib vaccine:

These problems are uncommon. If they occur, they usually begin soon after the shot and last 2 or 3 days.

Problems that could happen after any vaccine:

This information was taken directly from the Hib VIS
(This information taken from Hib VIS dated 02/04/14. If the actual VIS is more recent than this date, the information on this page needs to be updated.)

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HPV--Cervarix vaccine side-effects
(Human PapillomavirusCervarix vaccine)

What are the risks from HPV--Cervarix vaccine?

The HPV Cervarix® vaccine has been in use around the world for several years and has been very safe.

However, any medicine could possibly cause a serious problem, such as a severe allergic reaction. The risk of any vaccine causing a serious injury, or death, is extremely small.

Life-threatening allergic reactions from vaccines are very rare. If they do occur, it would be within a few minutes to a few hours after the vaccination.

Several mild to moderate problems are known to occur with this HPV vaccine. These do not last long and go away on their own.

Like all vaccines, HPV vaccines will continue to be monitored for unusual or severe problems.

This information was taken directly from the HPV-Cervarix VIS
(This information taken from HPV VIS dated 5/3/11. If the actual VIS is more recent than this date, the information on this page needs to be updated.)

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HPV--Gardasil vaccine side-effects
(Human Papillomavirus Gardasil vaccine)

What are the risks from HPV--Gardasil vaccine?

The HPV-Gardasil® vaccine has been used in the U.S. and around the world for about six years and has been very safe.

However, any medicine could possibly cause a serious problem, such as a severe allergic reaction. The risk of any vaccine causing a serious injury, or death, is extremely small.

Life-threatening allergic reactions from vaccines are very rare. If they do occur, it would be within a few minutes to a few hours after the vaccination.

Several mild to moderate problems are known to occur with this HPV vaccine. These do not last long and go away on their own.

Like all vaccines, HPV vaccines will continue to be monitored for unusual or severe problems.

This information was taken directly from the HPV-Gardasil VIS
(This information taken from HPV VIS dated 5/17/13. If the actual VIS is more recent than this date, the information on this page needs to be updated.)

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Influenza (inactivated) vaccine side-effects

What are the risks from inactivated influenza vaccine?

With a vaccine, like any medicine, there is a chance of side effects. These are usually mild and go away on their own.

Serious side effects are also possible, but are very rare. Inactivated flu vaccine does not contain live flu virus, so getting flu from this vaccine is not possible.

Brief fainting spells and related symptoms (such as jerking movements) can happen after any medical procedure, including vaccination. Sitting or lying down for about 15 minutes after a vaccination can help prevent fainting and injuries caused by falls. Tell your doctor if you feel dizzy or light-headed, or have vision changes or ringing in the ears.

Mild Problems

If these problems occur, they usually begin soon after the shot and last 1 or 2 days.

Moderate Problems

Young children who get inactivated flu vaccine and pneumococcal vaccine (PCV13) at the same time may be at increased risk for seizures caused by fever. Ask your doctor for more information. Tell your doctor if a child who is getting flu vaccine has ever had a seizure.

Severe Problems

The safety of vaccines is always being monitored. For more information, visit: Vaccine Safety Monitoring and Vaccine Safety Activities.

One brand of inactivated flu vaccine, called Afluria, should not be given to children 8 years of age or younger, except in special circumstances. A related vaccine was associated with fevers and fever-related seizures in young children in Australia. Your doctor can give you more information.

This information was taken directly from the Inactivated Influenza VIS
(This information taken from Inactivated Influenza VIS dated 7/26/2013. If the actual VIS is more recent than this date, the information on this page needs to be updated.)

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Influenza (live) vaccine side-effects

What are the risks from LAIV?

With a vaccine, like any medicine, there is a chance of side effects. These are usually mild and go away on their own.

Serious side effects are also possible, but are very rare. LAIV is made from weakened virus and does not cause flu.

Mild Problems
Some children and adolescents 2-17 years of age have reported:

Some adults 18-49 years of age have reported:

Severe Problems

A severe allergic reaction could occur after any vaccine (estimated less than 1 in a million doses).

The safety of vaccines is always being monitored. For more information, visit: Vaccine Safety Monitoring and Vaccine Safety Activities.

This information was taken directly from the LAIV VIS
(This information taken from Live Influenza VIS dated 7/2/12. If the actual VIS is more recent than this date, the information on this page needs to be updated.)

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JE-IXIARO vaccine side-effects
(Japanese Encephalitis - IXIARO)

What are the risks from Japanese encephalitis vaccine?

With a vaccine, like any medicine, there is a chance of side effects. When side effects happen, they are usually mild and go away on their own.

Mild Problems

Moderate or Severe Problems

Studies have shown that severe reactions to JE vaccine are very rare.

Problems that can happen after any vaccine

This information was taken directly from the JE-Ixiaro VIS
(This information taken from Japanese Encephalitis Ixiaro VIS dated 1/24/14. If the actual VIS is more recent than this date, the information on this page needs to be updated.)

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MMR vaccine side-effects
(Measles, Mumps, and Rubella)

What are the risks from MMR vaccine?

A vaccine, like any medicine, is capable of causing serious problems, such as severe allergic reactions.

The risk of MMR vaccine causing serious harm, or death, is extremely small.

Getting MMR vaccine is much safer than getting measles, mumps or rubella.

Most people who get MMR vaccine do not have any serious problems with it.

Mild Problems

If these problems occur, it is usually within 7-12 days after the shot. They occur less often after the second dose.

Moderate Problems

Severe Problems (Very Rare)

This information was taken directly from the MMR VIS
(This information taken from MMR VIS dated 4/20/12. If the actual VIS is more recent than this date, the information on this page needs to be updated.)

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MMRV vaccine side-effects
(Measles, Mumps, Rubella, and Varicella)

What are the risks from MMRV vaccine?

A vaccine, like any medicine, is capable of causing serious problems, such as severe allergic reactions. The risk of MMRV vaccine causing serious harm, or death, is extremely small.

Getting MMRV vaccine is much safer than getting measles, mumps, rubella, or chickenpox.

Most children who get MMRV vaccine do not have any problems with it.

Mild Problems

If these problems happen, it is usually within 5-12 days after the first dose. They happen less often after the second dose.

Moderate Problems

Severe Problems (Very Rare)
Several severe problems have been reported following MMR vaccine, and might also happen after MMRV. These include severe allergic reactions (fewer than 4 per million), and problems such as:

Because these problems occur so rarely, we can’t be sure whether they are caused by the vaccine or not.

This information was taken directly from the MMRV VIS
(This information taken from MMRV VIS dated 5/21/10. If the actual VIS is more recent than this date, the information on this page needs to be updated.)

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Meningococcal vaccine side-effects

What are the risks from meningococcal vaccines?

A vaccine, like any medicine, could possibly cause serious problems, such as severe allergic reactions. The risk of the meningococcal vaccine causing serious harm, or death, is extremely small.

Brief fainting spells and related symptoms (such as jerking or seizure-like movements) can follow a vaccination. They happen most often with adolescents, and they can result in falls and injuries.

Sitting or lying down for about 15 minutes after getting the shot - especially if you feel faint - can help prevent these injuries.

Mild Problems

As many as half the people who get meningococcal vaccines have mild side effects, such as redness or pain where the shot was given.

If these problems occur, they usually last for 1 or 2 days. They are more common after MCV4 than after MPSV4.

A small percentage of people who receive the vaccine develop a fever.

Severe Problems

Serious allergic reactions, within a few minutes to a few hours of the shot, are very rare.

This information was taken directly from the Meningococcal VIS
(This information taken from Meningococcal VIS dated 10/14/11. If the actual VIS is more recent than this date, the information on this page needs to be updated.)

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PCV13 vaccine side-effects
(Pneumococcal Conjugate Vaccine)

What are the risks from PCV13?

With any medicine, including vaccines, there is a chance of side effects. These are usually mild and go away on their own, but serious reactions are also possible.

Reported problems associated with PCV13 vary by dose and age, but generally:

Adults receiving the vaccine have reported redness, pain, and swelling where the shot was given. Mild fever, fatigue, headache, chills, or muscle pain have also been reported.

Life-threatening allergic reactions from any vaccine are very rare.

This information was taken directly from the PCV VIS
(This information taken from PCV VIS dated 2/27/13. If the actual VIS is more recent than this date, the information on this page needs to be updated.)

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PPSV23 vaccine side-effects
(Pneumococcal Polysaccharide)

What are the risks from PPSV?

About half of people who get PPSV have mild side effects, such as redness or pain where the shot is given.

Less than 1 percent develop a fever, muscle aches, or more severe local reactions.

A vaccine, like any medicine, could cause a serious reaction. But the risk of a vaccine causing serious harm, or death, is extremely small.

This information was taken directly from the PPSV VIS
(This information taken from PPSV VIS dated 10/6/09. If the actual VIS is more recent than this date, the information on this page needs to be updated.)

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Polio vaccine side-effects

What are the risks from IPV?

Some people who get Inactivated Polio Vaccine (IPV) get a sore spot where the shot was given. The vaccine used today has never been known to cause any serious problems, and most people don’t have any problems at all with it.

However, a vaccine, like any medicine, could cause serious problems, such as a severe allergic reaction or even death. The risk of a polio vaccine causing serious harm is extremely small.

This information was taken directly from the IPV VIS
(This information taken from IPV VIS dated 11/08/11. If the actual VIS is more recent than this date, the information on this page needs to be updated.)

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Rabies vaccine side-effects

What are the risks from rabies vaccine?

A vaccine, like any medicine, is capable of causing serious problems, such as severe allergic reactions. The risk of a vaccine causing serious harm, or death, is extremely small. Serious problems from rabies vaccine are very rare.

Mild Problems

Moderate Problems

Other nervous system disorders, such as Guillain Barré syndrome (GBS), have been reported after rabies vaccine, but this happens so rarely that it is not known whether they are related to the vaccine.

NOTE: Several brands of rabies vaccine are available in the United States, and reactions may vary between brands. Your provider can give you more information about a particular brand.

This information was taken directly from the Rabies VIS
(This information taken from Rabies VIS dated 10/6/09. If the actual VIS is more recent than this date, the information on this page needs to be updated.)

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Rotavirus vaccine side-effects

What are the risks from rotavirus vaccine?

With a vaccine, like any medicine, there is a chance of side effects. These are usually mild and go away on their own.

Serious side effects are also possible, but are very rare.

Most babies who get rotavirus vaccine do not have any problems with it. But some problems have been associated with rotavirus vaccine:

Mild problems

Babies might become irritable, or have mild, temporary diarrhea or vomiting after getting a dose of rotavirus vaccine.

Serious problems

Intussusception is a type of bowel blockage that is treated in a hospital, and could require surgery. It happens “naturally” in some babies every year in the United States, and usually there is no known reason for it.

There is also a small risk of intussusception from rotavirus vaccination, usually within a week after the 1st or 2nd vaccine dose. This additional risk is estimated to range from about 1 in 20,000 US infants to 1 in 100,000 US infants who get rotavirus vaccine. Your doctor can give you more information.

This information was taken directly from the Rotavirus VIS
(This information taken from Rotavirus VIS dated 8/26/13. If the actual VIS is more recent than this date, the information on this page needs to be updated.)

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Shingles (Herpes Zoster) vaccine side-effects

What are the risks from shingles vaccine?

A vaccine, like any medicine, could possibly cause serious problems, such as severe allergic reactions. However, the risk of a vaccine causing serious harm, or death, is extremely small.

No serious problems have been identified with shingles vaccine.

Mild Problems

Like all vaccines, shingles vaccine is being closely monitored for unusual or severe problems.

This information was taken directly from the Shingles VIS
(This information taken from Shingles VIS dated 10/6/09. If the actual VIS is more recent than this date, the information on this page needs to be updated.)

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Smallpox (Vaccinia) vaccine side-effects

This medication guide replaces the Smallpox VIS. It is to be used before one receives the vaccination. Medical Guide for vaccination with ACAM2000[8 pages] (10/1/09)

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Td vaccine (Adult Tetanus & Diphtheria)

What are the risks from Td vaccine?

With a vaccine, like any medicine, there is a chance of side effects. These are usually mild and go away on their own.

Serious side effects are also possible, but are very rare.

Most people who get Td vaccine do not have any problems with it.

Mild Problems following Td
(Did not interfere with activities)

Moderate Problems following Td
(Interfered with activities, but did not require medical attention)

Severe Problems following Td
(Unable to perform usual activities; required medical attention)

Problems that could happen after any vaccine:

This information was taken directly from the Td VIS
(This information taken from Td VIS dated 2/4/14. If the actual VIS is more recent than this date, the information on this page needs to be updated.)

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Tdap vaccine (Combined Tetanus, Diphtheria & Pertussis)

What are the risks from Tdap vaccine?

With any medicine, including vaccines, there is a chance of side effects. These are usually mild and go away on their own.

Brief fainting spells can follow a vaccination, leading to injuries from falling. Sitting or lying down for about 15 minutes can help prevent these. Tell your doctor if you feel dizzy or light-headed, or have vision changes or ringing in the ears.

Mild problems following Tdap
(Did not interfere with activities)

Mild problems following Tdap
(Interfered with activities, but did not require medical attention)

Severe problems following Tdap
(Unable to perform usual activities; required medical attention)

A severe allergic reaction could occur after any vaccine (estimated to occur less than once in a million doses).

This information was taken directly from the Tdap VIS
(This information taken from Td-Tdap VIS dated 5/9/13. If the actual VIS is more recent than this date, the information on this page needs to be updated.)

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Typhoid vaccine side-effects

What are the risks from typhoid vaccine?

Like any medicine, a vaccine could cause a serious problem, such as a severe allergic reaction. The risk of typhoid vaccine causing serious harm, or death, is extremely small. Serious problems from either typhoid vaccine are very rare.

Inactivated Typhoid Vaccine (Shot)

  Mild Reactions

Live Typhoid Vaccine (Oral)

  Mild Reactions

This information was taken directly from the Typhoid VIS
(This information taken from Typhoid VIS dated 5/29/12. If the actual VIS is more recent than this date, the information on this page needs to be updated.)

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Varicella (Chickenpox) vaccine side-effects

What are the risks from chickenpox vaccine?

A vaccine, like any medicine, is capable of causing serious problems, such as severe allergic reactions. The risk of chickenpox vaccine causing serious harm, or death, is extremely small.

Getting chickenpox vaccine is much safer than getting chickenpox disease. Most people who get chickenpox vaccine do not have any problems with it. Reactions are usually more likely after the first dose than after the second.

Mild Problems

Note: The first dose of MMRV vaccine has been associated with rash and higher rates of fever than MMR and varicella vaccines given separately. Rash has been reported in about 1 person in 20 and fever in about 1 person in 5. Seizures caused by a fever are also reported more often after MMRV. These usually occur 5-12 days after the first dose.

Moderate Problems

Severe Problems

Other serious problems, including severe brain reactions and low blood count, have been reported after chickenpox vaccination. These happen so rarely experts cannot tell whether they are caused by the vaccine or not. If they are, it is extremely rare.

This information was taken directly from the Varicella VIS
(This information taken from Varicella VIS dated 3/13/08. If the actual VIS is more recent than this date, the information on this page needs to be updated.)

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Yellow Fever vaccine side-effects

What are the risks from Yellow Fever vaccine?

A vaccine, like any medicine, could cause a serious reaction. But the risk of a vaccine causing serious harm, or death, is extremely low.

Mild Problems

Yellow fever vaccine has been associated with fever, and with aches, soreness, redness or swelling where the shot was given.

These problems occur in up to 1 person out of 4. They usually begin soon after the shot, and can last up to a week.

Severe Problems

This information was taken directly from the Yellow Fever VIS
(This information taken from Yellow Fever VIS dated 3/30/11. If the actual VIS is more recent than this date, the information on this page needs to be updated.)

What if there is a moderate or severe reaction?

What should I look for?

What should I do?

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