Contraindications for the flu vaccine include a severe egg or chicken allergy, moderate to severe illness with fever, and a previous history of Guillain Barre Syndrome. If considering the nasal spray instead of the shot, additional contraindications for the flu vaccine are a weak immune system, wheezing episodes or asthma, and muscle and nerve disorders like cerebral palsy. Reactions to the flu vaccine are very rare, but anyone who is unsure about getting vaccinated should consult with his or her health care provider.
The type of vaccine given determines the contraindications. The flu shot contains a dead virus that cannot infect anyone and is considered safe for children as well as those with chronic diseases and conditions. In contrast, the nasal spray contains a live but weakened flu virus. It is considered safe for healthy people who are not pregnant and are between the ages of two and 49.
There are several important contraindications for the flu vaccine. Those with a severe allergy to chicken or eggs should not get the flu shot because it may contain egg proteins. If the vaccine is absolutely necessary, it can be given with an allergist nearby who can treat the patient immediately if there is a reaction.
Anyone who is sick with a fever should wait to get the vaccine until he or she has fully recovered. This is because the vaccine is meant to cause the immune system to react. Someone who is sick should not tax his or her immune system unnecessarily by getting vaccinated. Additionally, it would be difficult to separate a reaction to the vaccine from symptoms of the disease if a reaction were to occur.
Another contraindication is a history of Guillain Barre Syndrome. This syndrome is serious and results when the immune system attacks the nervous system, causing muscle weakness. It is possible but not certain that some cases of this condition were caused by the 1976 swine flu vaccine, and therefore people with a history of Guillain Barre should not be vaccinated for influenza.
There are additional contraindications for the flu vaccine if it is administered as a nasal spray. Pregnant women and people with weak immune systems should not receive this type of flu vaccine because it contains a weakened live virus. Healthy people in routine contact with anyone with a compromised immune system should also not get the nasal spray because they can inadvertently transmit the virus. This type of flu vaccine is not recommended for anyone with asthma or a disorder that can cause breathing problems. Finally, children between six and 23 months old and those more than the age of 50 should get the injection instead.
Any side effects caused by the flu vaccine are typically very mild and do not last long. Most people may experience some soreness at the injection site that can last for a day or two. As the goal of the vaccine is to provoke the immune system to react and create influenza antibodies, is it common to experience some low-grade fever, aches, and nausea after being vaccinated. Rarely, the vaccine may cause a severe allergic reaction requiring medical intervention.
The flu vaccine is recommended for anyone more than six months old, especially those at a high risk of developing complications from the disease. Most people who contract an influenza virus get better within two weeks, but some develop complications like ear and sinus infections and bacterial pneumonia. Preexisting medical conditions like asthma and diabetes can worsen with the flu. Some complications can be fatal if left untreated.