Possible Side-effects from Vaccines

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:

• headaches, upper respiratory tract infection (about 1 person in 3)
• stuffy nose, sore throat, joint pain (about 1 person in 6)
• abdominal pain, cough, nausea (about 1 person in 7)
• diarrhea (about 1 person in 10)
• fever (about 1 person in 100)

Serious Problems

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

• blood in the urine or stool
• pneumonia
• inflammation of the stomach or intestines

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.

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

• Reactions on the arm where the shot was given:
  • Tenderness (about 1 person out of 2)
  • Redness (about 1 out of 7 men and 1 out of 3 women)
  • Itching (about 1 out of 50 men and 1 out of 20 women)
  • Lump (about 1 out of 60 men and 1 out of 16 women)
  • Bruise (about 1 out of 25 men and 1 out of 22 women)
• Muscle aches or temporary limitation of arm movement (about 1 out of 14 men and 1 out of 10 women).
• Headaches (about 1 out of 25 men and 1 out of 12 women).
• Fatigue (about 1 out of 15 men, about 1 out of 8 women).

Severe Problems

• Serious allergic reaction (very rare – less than once in 100,000 doses).

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.

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)

• Fever (up to about 1 child in 4)
• Redness or swelling where the shot was given (up to about 1 child in 4)
• Soreness or tenderness where the shot was given (up to about 1 child in 4)

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, lasting 1-7 days (up to about 1 child in 30).

Other mild problems include:

• Fussiness (up to about 1 child in 3)
• Tiredness or poor appetite (up to about 1 child in 10)
• Vomiting (up to about 1 child in 50)

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

Moderate Problems (Uncommon)

• Seizure (jerking or staring) (about 1 child out of 14,000)
• Non-stop crying, for 3 hours or more (up to about 1 child out of 1,000)
• High fever, over 105°F (about 1 child out of 16,000)

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:
  • Long-term seizures, coma, or lowered consciousness
  • Permanent brain damage.

  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.

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.

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

Minor problems following hepatitis A vaccine include:

• soreness or redness where the shot was given
• low-grade fever
• headache
• tiredness

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

Your doctor can tell you more about these reactions.

Other problems that could happen after this vaccine:

• People sometimes faint after a medical procedure, including vaccination. Sitting or lying down for about 15 minutes can help prevent fainting, and injuries caused by a fall. Tell your provider if you feel dizzy, or have vision changes or ringing in the ears.
• Some people get shoulder pain that can be more severe and longer lasting than the more routine soreness that can follow injections. This happens very rarely.
• Any medication can cause a severe allergic reaction. Such reactions from a vaccine are very rare, estimated at about 1 in a million doses, and would happen within a few minutes to a few hours after the vaccination.

As with any medicine, there is a very remote chance of a vaccine causing a serious injury or death.

The safety of vaccines is always being monitored. For more information, visit the vaccine safety site.

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.

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

Minor problems following hepatitis B vaccine include:

• soreness where the shot was given
• temperature of 99.9°F or higher

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

Your doctor can tell you more about these reactions.

Other problems that could happen after this vaccine:

• People sometimes faint after a medical procedure, including vaccination. Sitting or lying down for about 15 minutes can help prevent fainting and injuries caused by a fall. Tell your provider if you feel dizzy, or have vision changes or ringing in the ears.
• Some people get shoulder pain that can be more severe and longer-lasting than the more routine soreness that can follow injections. This happens very rarely.
• Any medication can cause a severe allergic reaction. Such reactions from a vaccine are very rare, estimated at about 1 in a million doses, and would happen within a few minutes to a few hours after the vaccination.

As with any medicine, there is a very remote chance of a vaccine causing a serious injury or death.

The safety of vaccines is always being monitored. For more information, visit the vaccine safety site.

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

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

Mild Problems following Hib vaccine:

• redness, warmth, or swelling where the shot was given
• fever

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:

Any medication can cause a severe allergic reaction. Such reactions from a vaccine are very rare, estimated at fewer than 1 in a million doses, and would happen within a few minutes to a few hours after the vaccination.

As with any medicine, there is a very remote chance of a vaccine causing a serious injury or death.

Older children, adolescents, and adults might also experience these problems after any vaccine:

• People sometimes faint after a medical procedure, including vaccination. Sitting or lying down for about 15 minutes can help prevent fainting, and injuries caused by a fall. Tell your doctor if you feel dizzy, or have vision changes or ringing in the ears.
• Some people get severe pain in the shoulder and have difficulty moving the arm where a shot was given. This happens very rarely.

The safety of vaccines is always being monitored. For more information, visit the vaccine safety site.

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.

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

Mild or moderate problems following HPV vaccine:

• Reactions in the arm where the shot was given:
  • Soreness (about 9 people in 10)
  • Redness or swelling (about 1 person in 3)

• Fever:
  • Mild (100°F) (about 1 person in 10)
  • Moderate (102°F) (about 1 person in 65)

• Other problems:
  • Headache (about 1 person in 3)

Problems that could happen after any injected vaccine:

• People sometimes faint after a medical procedure, including vaccination. Sitting or lying down for about 15 minutes can help prevent fainting and injuries caused by a fall. Tell your doctor if you feel dizzy, or have vision changes or ringing in the ears.
• Some people get severe pain in the shoulder and have difficulty moving the arm where a shot was given. This happens very rarely.
• Any medication can cause a severe allergic reaction. Such reactions from a vaccine are very rare, estimated at about 1 in a million doses, and would happen within a few minutes to a few hours after the vaccination.

As with any medicine, there is a very remote chance of a vaccine causing a serious injury or death.

The safety of vaccines is always being monitored. For more information, visit the vaccine safety site.

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

Most people who get a flu shot do not have any problems with it.

Minor problems following a flu shot include:

• soreness, redness, or swelling where the shot was given
• hoarseness
• sore, red or itchy eyes
• cough
• fever
• aches
• headache
• itching
• fatigue

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

More serious problems following a flu shot can include the following:

• There may be a small increased risk of Guillain-Barré Syndrome (GBS) after inactivated flu vaccine. This risk has been estimated at 1 or 2 additional cases per million people vaccinated. This is much lower than the risk of severe complications from flu, which can be prevented by flu vaccine.
• Young children who get the flu shot along with pneumococcal vaccine (PCV13), and/or DTaP vaccine at the same time might be slightly more likely to have a seizure 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.

Problems that could happen after any injected vaccine:

• People sometimes faint after a medical procedure, including vaccination. Sitting or lying down for about 15 minutes can help prevent fainting, and injuries caused by a fall. Tell your doctor if you feel dizzy, or have vision changes or ringing in the ears.
• Some people get severe pain in the shoulder and have difficulty moving the arm where a shot was given. This happens very rarely.
• Any medication can cause a severe allergic reaction. Such reactions from a vaccine are very rare, estimated at about 1 in a million doses, and would happen within a few minutes to a few hours after the vaccination.

As with any medicine, there is a very remote chance of a vaccine causing a serious injury or death.

The safety of vaccines is always being monitored. For more information, visit the vaccine safety web site.

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

Most people who get LAIV do not have any problems with it. Reactions to LAIV may resemble a very mild case of flu.

Problems that have been reported following LAIV:

Children and adolescents 2-17 years of age:

• runny nose/nasal congestion
• cough
• fever
• headache and muscle aches
• wheezing
• abdominal pain, vomiting, or diarrhea

Adults 18-49 years of age:

• runny nose/nasal congestion
• sore throat
• cough
• chills
• tiredness/weakness
• headache

Problems that could happen after any vaccine:

• Any medication can cause a severe allergic reaction. Such reactions from a vaccine are very rare, estimated at about 1 in a million doses, and would happen within a few minutes to a few hours after the vaccination.

As with any medicine, there is a very small chance of a vaccine causing a serious injury or death.

The safety of vaccines is always being monitored. For more information, visit the vaccine safety web site.

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

• Pain, tenderness, redness, or swelling where the shot was given (about 1 person in 4).
• Fever (mainly in children).
• Headache, muscle aches (mainly in adults).

Moderate or Severe problems

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

Problems that can happen after any vaccine

• Brief fainting spells can happen after any medical procedure, including vaccination. Sitting or lying down for about 15 minutes can help prevent fainting, and injuries caused by a fall. Tell your doctor if you feel dizzy, or have vision changes or ringing in the ears.
• Lasting shoulder pain and reduced range of motion in the arm where the shot was given can happen, very rarely, after a vaccination.
• Severe allergic reactions from a vaccine are very rare, estimated at less than 1 in a million doses. If one were to occur, it would usually be within a few minutes to a few hours after the vaccination.

The safety of vaccines is always being monitored.

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

• Fever (up to 1 person out of 6)
• Mild rash (about 1 person out of 20)
• Swelling of glands in the cheeks or neck (about 1 person out of 75)

If these problems occur, it is usually within 6-14 days after the shot. They occur less often after the second dose.

Moderate problems

• Seizure (jerking or staring) caused by fever (about 1 out of 3,000 doses)
• Temporary pain and stiffness in the joints, mostly in teenage or adult women (up to 1 out of 4)
• Temporary low platelet count, which can cause a bleeding disorder (about 1 out of 30,000 doses)

Severe problems (very rare)

• Serious allergic reaction (less than 1 out of a million doses)
• Several other severe problems have been reported after a child gets MMR vaccine, including:
  • Deafness
  • Long-term seizures, coma, or lowered consciousness
  • Permanent brain damage

These are so rare that it is hard to tell whether they are caused by the 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

• Fever (about 1 child out of 5).
• Mild rash (about 1 child out of 20).
• Swelling of glands in the cheeks or neck (rare).

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

• Seizure caused by fever (about 1 child in 1,250 who get MMRV), usually 5-12 days after the first dose. They happen less often when MMR and varicella vaccines are given at the same visit as separate shots (about 1 child in 2,500 who get these two vaccines), and rarely after a 2nd dose of MMRV.
• Temporary low platelet count, which can cause a bleeding disorder (about 1 child out of 40,000).

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:

• Deafness.
• Long-term seizures, coma, lowered consciousness.
• Permanent brain damage.

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

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

As many as half of the people who get meningococcal ACWY vaccine have mild problems following vaccination, such as redness or soreness where the shot was given. If these problems occur, they usually last for 1 or 2 days. They are more common after MenACWY than after MPSV4.

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

Problems that could happen after any injected vaccine:

• People sometimes faint after a medical procedure, including vaccination. Sitting or lying down for about 15 minutes can help prevent fainting, and injuries caused by a fall. Tell your doctor if you feel dizzy, or have vision changes or ringing in the ears.  
• Some people get severe pain in the shoulder and have difficulty moving the arm where a shot was given. This happens very rarely. 
• Any medication can cause a severe allergic reaction. Such reactions from a vaccine are very rare, estimated at about 1 in a million doses, and would happen within a few minutes to a few hours after the vaccination.

As with any medicine, there is a very remote chance of a vaccine causing a serious injury or death.

The safety of vaccines is always being monitored. For more information, visit the vaccine safety site.

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

Problems reported following PCV13 varied by age and dose in the series. The most common problems reported among children were:

• About half became drowsy after the shot, had a temporary loss of appetite, or had redness or tenderness where the shot was given.
• About 1 out of 3 had swelling where the shot was given.
• About 1 out of 3 had a mild fever, and about 1 in 20 had a fever over 102.2°F.
• Up to about 8 out of 10 became fussy or irritable.

Adults have reported pain, redness, and swelling where the shot was given; also mild fever, fatigue, headache, chills, or muscle pain.

Young children who get PCV13 along with inactivated flu vaccine at the same time may be at increased risk for seizures caused by fever. Ask your doctor for more information.

Problems that could happen after any vaccine:

• People sometimes faint after a medical procedure, including vaccination. Sitting or lying down for about 15 minutes can help prevent fainting, and injuries caused by a fall. Tell your doctor if you feel dizzy, or have vision changes or ringing in the ears.
• Some older children and adults get severe pain in the shoulder and have difficulty moving the arm where a shot was given. This happens very rarely.
• Any medication can cause a severe allergic reaction. Such reactions from a vaccine are very rare, estimated at about 1 in a million doses, and would happen within a few minutes to a few hours after the vaccination.

As with any medicine, there is a very small chance of a vaccine causing a serious injury or death.

The safety of vaccines is always being monitored. For more information, visit CDC’s Vaccine Safety website.

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.

About half of people who get PPSV have mild side effects, such as redness or pain where the shot is given, which go away within about two days.

Less than 1 out of 100 people develop a fever, muscle aches, or more severe local reactions.

Problems that could happen after any vaccine:

• People sometimes faint after a medical procedure, including vaccination. Sitting or lying down for about 15 minutes can help prevent fainting, and injuries caused by a fall. Tell your doctor if you feel dizzy, or have vision changes or ringing in the ears.
• Some people get severe pain in the shoulder and have difficulty moving the arm where a shot was given. This happens very rarely.
• Any medication can cause a severe allergic reaction. Such reactions from a vaccine are very rare, estimated at about 1 in a million doses, and would happen within a few minutes to a few hours after the vaccination.

As with any medicine, there is a very remote chance of a vaccine causing a serious injury or death.

The safety of vaccines is always being monitored. For more information, visit CDC’s vaccine safety website.

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.

Some people who get IPV get a sore spot where the shot was given. IPV has not been known to cause serious problems, and most people do not have any problems with it.

Other problems that could happen after this vaccine:

• People sometimes faint after a medical procedure, including vaccination. Sitting or lying down for about 15 minutes can help prevent fainting and injuries caused by a fall. Tell your provider if you feel dizzy, or have vision changes or ringing in the ears.
• Some people get shoulder pain that can be more severe and longer-lasting than the more routine soreness that can follow injections. This happens very rarely.
• Any medication can cause a severe allergic reaction. Such reactions from a vaccine are very rare, estimated at about 1 in a million doses, and would happen within a few minutes to a few hours after the vaccination.

As with any medicine, there is a very remote chance of a vaccine causing a serious injury or death.

The safety of vaccines is always being monitored. For more information, visit the vaccine safety site.

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

• soreness, redness, swelling, or itching where the shot was given (30% – 74%)
• headache, nausea, abdominal pain, muscle aches, dizziness (5% – 40%)

Moderate problems

• hives, pain in the joints, fever (about 6% of booster doses)

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.

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 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 following rotavirus vaccine:

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

Serious problems following rotavirus vaccine:

• 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 1^st or 2^nd vaccine dose. This additional risk is estimated to range from about 1 in 20,000 to 1 in 100,000 US infants who get rotavirus vaccine. Your doctor can give you more information.

Problems that could happen after any vaccine:

• Any medication can cause a severe allergic reaction. Such reactions from a vaccine are very rare, estimated at fewer than 1 in a million doses, and usually happen within a few minutes to a few hours after the vaccination.

As with any medicine, there is a very remote chance of a vaccine causing a serious injury or death.

The safety of vaccines is always being monitored. For more information, visit the Vaccine Safety site.

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

• Redness, soreness, swelling, or itching at the site of the injection (about 1 person in 3).
• Headache (about 1 person in 70).

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

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

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

Mild Problems following Td vaccine:
(Did not interfere with activities)

• Pain where the shot was given (about 8 people in 10)
• Redness or swelling where the shot was given (about 1 person in 4)
• Mild fever (rare)
• Headache (about 1 person in 4)
• Tiredness (about 1 person in 4)

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

• Fever over 102°F (rare)

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

• Swelling, severe pain, bleeding and/or redness in the arm where the shot was given (rare).

Problems that could happen after any vaccine:

• People sometimes faint after a medical procedure, including vaccination. Sitting or lying down for about 15 minutes can help prevent fainting, and injuries caused by a fall. Tell your doctor if you feel dizzy, or have vision changes or ringing in the ears.
• Some people get severe pain in the shoulder and have difficulty moving the arm where a shot was given. This happens very rarely.
• Any medication can cause a severe allergic reaction. Such reactions from a vaccine are very rare, estimated at fewer than 1 in a million doses, and would happen within a few minutes to a few hours after the vaccination.

As with any medicine, there is a very remote chance of a vaccine causing a serious injury or death.

The safety of vaccines is always being monitored. For more information, visit the Vaccine Safety site.

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

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

Mild problems following Tdap:
(Did not interfere with activities)

• Pain where the shot was given (about 3 in 4 adolescents or 2 in 3 adults)
• Redness or swelling where the shot was given (about 1 person in 5)
• Mild fever of at least 100.4°F (up to about 1 in 25 adolescents or 1 in 100 adults)
• Headache (about 3 or 4 people in 10)
• Tiredness (about 1 person in 3 or 4)
• Nausea, vomiting, diarrhea, stomach ache (up to 1 in 4 adolescents or 1 in 10 adults)
• Chills, sore joints (about 1 person in 10)
• Body aches (about 1 person in 3 or 4)
• Rash, swollen glands (uncommon)

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

• Pain where the shot was given (up to 1 in 5 or 6)
• Redness or swelling where the shot was given (up to about 1 in 16 adolescents or 1 in 12 adults)
• Fever over 102°F (about 1 in 100 adolescents or 1 in 250 adults)
• Headache (about 1 in 7 adolescents or 1 in 10 adults)
• Nausea, vomiting, diarrhea, stomach ache (up to 1 or 3 people in 100)
• Swelling of the entire arm where the shot was given (up to about 1 in 500).

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

• Swelling, severe pain, bleeding, and redness in the arm where the shot was given (rare).

Problems that could happen after any vaccine:

• People sometimes faint after a medical procedure, including vaccination. Sitting or lying down for about 15 minutes can help prevent fainting, and injuries caused by a fall. Tell your doctor if you feel dizzy, or have vision changes or ringing in the ears.
• Some people get severe pain in the shoulder and have difficulty moving the arm where a shot was given. This happens very rarely.
• Any medication can cause a severe allergic reaction. Such reactions from a vaccine are very rare, estimated at fewer than 1 in a million doses, and would happen within a few minutes to a few hours after the vaccination.

As with any medicine, there is a very remote chance of a vaccine causing a serious injury or death.

The safety of vaccines is always being monitored. For more information, visit the Vaccine Safety site.

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

• Fever (up to about 1 person in 100)
• Headache (up to about 1 person in 30)
• Redness or swelling at the site of the injection (up to about 1 person in 15)

Live typhoid vaccine (Oral)
Mild reactions

• Fever or headache (up to about 1 person in 20)
• Stomach pain, nausea, vomiting, rash (rare)

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

• Soreness or swelling where the shot was given (about 1 out of 5 children and up to 1 out of 3 adolescents and adults)
• Fever (1 person out of 10, or less)
• Mild rash, up to a month after vaccination (1 person out of 25). It is possible for these people to infect other members of their household, but this is extremely rare.

Moderate problems

• Seizure (jerking or staring) caused by fever (very rare).

Severe problems

• Pneumonia (very rare)

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.

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

• Severe allergic reaction to a vaccine component (about 1 person in 55,000).
• Severe nervous system reaction (about 1 person in 125,000).
• Life-threatening severe illness with organ failure (about 1 person in 250,000). More than half the people who suffer this side effect die.

These last two problems have never been reported after a booster dose.