Is It Possible to Prevent Flu in Adults?
- Limit touching high-touch surfaces where flu viruses may remain alive; examples include handrails, doorknobs, faucets, keyboards, and elevator buttons.
- Wash your hands often, especially after touching high-touch surfaces, being in public places, or at work.
- Avoid touching your eyes, nose, or mouth before washing one's hands.
- Avoid close contact with people who appear ill.
- Do not share clothes or other personal items with another person during a flu outbreak.
- Those infected with influenza should stay at home for 24 hours after fevers have resolved.
The best means of preventing the flu is getting an influenza vaccination. The CDC recommends an annual flu vaccine for everyone 6 months of age and older. Two general types of vaccines are available. One is the injectable vaccine (known as the flu shot) made from inactivated virus. The flu shot contains only killed influenza viruses A and B.
The other is a live attenuated, or weakened, virus that is squirted into the nose. This is called intranasal vaccine or nasal spray vaccine. The intranasal form is indicated for certain people who may prefer it to a shot, and it is approved for people from 2 through 49 years of age. It is not recommended for people who are immunosuppressed or have other conditions (see below for a list). There have been concerns about poorer effectiveness than injected vaccines, however, and the Advisory Committee on Immunization Practices (ACIP) recommended against its use during flu seasons in 2016-17 and 2017-18.
There are different injected flu vaccines, such as the quadrivalent flu shot, which contains two type A viruses and two type Bs rather than the standard trivalent that has two type As and one type B. There is a high-dose shot formulation for people over 65 years of age and an intradermal (into the skin) version for people ages 18-65, and it uses a tiny needle. In August 2014, the FDA approved Afluria, which is injected into the muscle through a needle-free jet injector. A complete listing of flu vaccines that are currently available can be found at http://www.immunize.org/catg.d/p4072.pdf.
An important point is that no one vaccine is recommended over the others and one should not delay getting vaccinated in order to wait for one of the others if there is a vaccine available.
It is also important to note a widely circulated study that reported a weak, inconclusive link of flu vaccination with miscarriage; in essence, there was a slightly higher number of miscarriages in a group of women who received flu vaccine compared to usual, but there was no evidence that the vaccine caused this. Because the risk of serious flu complications and death during pregnancy is clear and far higher, the American College of Obstetricians and Gynecologists (ACOG) recommends flu vaccination as an essential part of prenatal care.
Lastly, research has shown that flu vaccination is safe in most people who have all but the most severe egg allergy. People who can eat lightly cooked eggs, for example, are not likely to be allergic to eggs. People who have only experienced hives after exposure to eggs can receive any of the licensed flu vaccines that are approved for their age and health. They may also receive the vaccine at any facility licensed to give it, such as a local pharmacy or health fair.
People who have had reactions more severe than hives after eating eggs may receive any licensed flu vaccine, but they should receive it in a facility that is staffed with health professionals and equipped to manage severe allergic reactions. This need not be a doctor's office or hospital, nor is there a prescribed 30 minute observation period after receiving the vaccine. Health professionals giving vaccines to anyone should be able to recognize severe allergic reactions. Symptoms and signs may include throat or tongue swelling, lightheadedness, repeated vomiting, or difficulty breathing, and may require the use of epinephrine or emergency medical treatment.
The influenza vaccine is given every year prior to flu season. Immunity to the flu virus develops after about two weeks. The CDC recommends that vaccine be given starting as soon as it becomes available each fall.
- Because of substantial vaccine distribution delays during previous influenza seasons and the possibility of similar delays in the future, it is recommended that anyone at high risk for complications from the flu get a flu shot as early as September. This same group of people can still get the vaccine throughout the flu season if they were unable to be vaccinated earlier.
- The vaccine is effective in about 70%-90% of those who get the shot, especially in older people. Not only does it decrease the risk of getting flu infection, but it can also decrease the number of visits to a doctor's office, hospitalizations, and risk of death from the flu virus. However, in some years, the vaccine is less effective because the circulating flu virus has genetically changed from the ones anticipated and included in the vaccine. The 2014-15 flu vaccine was only 23% effective due to changes in the circulating flu virus that season.