Influenza (Flu) Vaccine

Influenza is a disease caused by a virus that is spread via droplet through sneezing, coughing, and talking. Every year about 200,000 people are infected and hospitalize due to flu. On average 5% to 20% of population in US gets the flu.

Influenza “flu” is a very serious disease as it can affect millions of people around the world. It is unpredictable as the strain of the virus is unstable and mutates (antigenic shift/drift). Influenza virus generally has three types, Type A, B, and C. Type A virus can infect humans, birds, pigs, horses, and whales. The natural host of type A viruses are wild birds and they typically don’t get sick (immune), however when domestic poultry birds such as chicken, duck, turkey, etc acquire the avian influenza they get sick and often die.

Influenza Type A virus are divided into two sub types (HA) Hemagglutenin and (NA) Nueraminadase. A combination of HA and NA subtypes are currently in general circulation ex: H1N1. Influenza Type B are found in humans, It is less virulent than type A. Type B virus hasn’t cause any Pandemics but can cause epidemics. Influenza Type C is less virulent than Type B, it only cause mild illness in human and do not cause pandemic nor epidemics. Type B and C do not have subtypes.

Flu is highly contagious and infectious; when people get infected the virus targets the respiratory system causing symptoms such as cough, Sore throat, Runny nose, head/body ache, Fatigue, and fever (not everyone with flu will have a fever). Super infection may occur (bacterial infection on top of respiratory infection) simultaneously for people who are imunocompromised, elderly, and very young so vaccination is very important.

Influenza vaccines are designed to combat the circulating influenza virus. There are two types of flu vaccines: Flu shots (inactivated vaccine) and Nasal spray (Live attenuated vaccine). Flu shots contained killed virus and is administered using a syringe injected into the muscle (intramuscular injection, there are three different shots available for different groups of people. Flu shot is contraindicated for people who have a history Guillain-Barré syndrome (GBS)

Nasal Spray Vaccine is made of live weaken virus administered via nasal spray, this type of vaccine is recommended for healthy people ages 2 to 49 y/o. Nasal spray vaccine is contraindicated for pregnant woman.

Viruses constantly mutate so scientist study the mutation and create a vaccine that can fight the emerging new strain. It is recommended to get vaccinated once flu vaccine is available in the community or before the start of flu season (September) as it takes approximately two weeks before our body can produce antibodies against the virus.

High Risk Group who should receive flu vaccine Who should not get vaccinated

What to Know Before the Procedure:

The best time to schedule an appointment with your physician at least 2 weeks in advance. Inform your doctor of any prior surgeries, medicine used, familial or personal history of GBS, allergies to any medication, etc. you also need to inform your doctor of the possibility that you are pregnant so your physician can evaluate as to when the vaccine can be given.

What to Expect After the Procedure:

Patient may experience soreness for a couple of days However; most of the discomfort subsides with prescription medication and rest. Patients can return to work after just a couple of days. Light activities can be resumed after recovery. If discomfort still continue it is best to contact your physician.