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The upcoming season’s flu vaccine will protect against the influenza viruses that research indicates will be most common during the season. This includes an influenza A (H1N1) virus, an influenza A (H3N2) virus and one or two influenza B viruses, depending on the flu vaccine.

Public health officials recom­mend that everyone who is eligible receive their flu vaccine and get it every year.


Common questions #

Which viruses does the seasonal flu vaccine protect against? #

The seasonal flu vaccine protects against the influenza viruses that research indicates will be most common during the upcoming season. Tradi­tional flu vaccines (called triva­lent vaccines) are made to protect against three flu viruses: an influenza A (H1N1) virus, an influenza A (H3N2) virus and an influenza B virus. There also are flu vaccines made to protect against four flu viruses (called quadri­va­lent” vaccines). These vaccines protect against the same viruses as the triva­lent vaccine as well as an additional B virus.

Can flu vaccines cause the flu? #

No. Flu vaccines that are admin­is­tered with a needle are currently made in two ways: The vaccine is made either with a) viruses that have been inacti­vated’ (killed) and are there­fore not infec­tious or b) with no flu viruses at all (which is the case for recom­bi­nant influenza vaccine). The nasal spray flu vaccine does contain live viruses. However, the viruses are atten­u­ated (weakened) and there­fore cannot cause flu illness. The weakened viruses are cold-adapted, which means they are designed to only cause infec­tion only at the cooler temper­a­tures found within the nose. The viruses cannot infect the lungs or other areas where warmer temper­a­tures exist.

What about side effects? #

Flu vaccines are safe. Serious problems from the flu vaccine are very rare. The most common side effect that a person is likely to experi­ence is either soreness where the injec­tion was given, or runny nose in the case of nasal spray. These side effects are gener­ally mild and usually go away after a day or two. Visit Influenza Vaccine Safety (www​.cdc​.gov/​f​l​u​/​p​r​o​t​e​c​t​/​v​a​c​c​i​n​e​/​v​a​c​c​i​n​e​safety.htm) for more information.


About influenza viruses #

Influenza viruses are constantly changing. They can change in two different ways. One way they change is called antigenic drift.” These are small changes in the genes of influenza viruses that happen contin­u­ally over time as the virus repli­cates. These small genetic changes usually produce viruses that are closely related to one another, which can be illus­trated by their location close together on a phylo­ge­netic tree. Viruses that are closely related to each other usually share the same antigenic proper­ties, and an immune system exposed to a similar virus will usually recog­nize it and respond. (This is sometimes called cross-protection.)

The other type of change is called antigenic shift.” Antigenic shift is an abrupt, major change in the influenza A viruses, resulting in new hemag­glu­tinin and/​or new hemag­glu­tinin and neuraminidase proteins in influenza viruses that infect humans. Shift results in a new influenza A subtype or a virus with a hemag­glu­tinin or a hemag­glu­tinin and neuraminidase combi­na­tion that has emerged from an animal popula­tion that is so different from the same subtype in humans that most people do not have immunity to the new (e.g., novel) virus.

Such a shift” occurred in the spring of 2009, when an H1N1 virus with a new combi­na­tion of genes emerged to infect people and quickly spread, causing a pandemic. When shift happens, most people have little or no protec­tion against the new virus. While influenza viruses are changing by antigenic drift all the time, antigenic shift happens only occasion­ally. Type A viruses undergo both kinds of changes; influenza type B viruses change only by the more gradual process of antigenic drift.


What hospitals report #

The Centers for Disease Control and Prevention’s National Health­care Safety Network tracks health care-associ­ated infec­tions. The network also is used to track health care process measures such as health care personnel influenza vaccine status and infec­tion control adher­ence rates.

Hospi­tals must count vacci­na­tion rates for anyone who works for any part of one day in the health care facility between October 1 and March 31. That includes everyone from volun­teers and clerical workers to doctors and execu­tives. Organi­za­tions then report their rates to the National Health­care Safety Network for public reporting on Hospital Compare, where the percentage of health­care workers given influenza vacci­na­tions is one of the measures displayed.


WSNA's position on mandatory influenza vaccinations and strategies to address influenza #

WSNA is committed to advocating for the health of nurses, patients and the commu­ni­ties they serve. Because of this commit­ment, WSNA strongly recom­mends that all nurses and other health care providers be vacci­nated against all influenza viruses. WSNA strongly supports and urges volun­tary efforts that aim for 100 percent vacci­na­tion rates, including annual educa­tion and imple­men­ta­tion of compre­hen­sive influenza vacci­na­tion programs for all health care providers.

WSNA supports enforce­ment of existing federal and state regula­tions to ensure that all employers meet the Centers for Disease Control (CDC) and Occupa­tional Health and Safety Admin­is­tra­tion (OSHA) require­ments for influenza prevention.

WSNA believes a hospital-by-hospital approach to manda­tory vacci­na­tions is poor public policy. It lacks consis­tency and adequate protec­tion for patients and health care workers. WSNA believes that any vacci­na­tion policy is only one compo­nent of a compre­hen­sive influenza preven­tion policy and should only be enacted as a result of federal or public health regula­tion. WSNA believes that any such regula­tion must include the following core components:

  • The policy must cover all health care settings and health care workers. This includes all settings such as hospi­tals, long-term care facil­i­ties, adult boarding homes, outpa­tient clinics, etc. Health care workers must include those licensed and unlicensed who work in close proximity to patients, (e.g. nurses, emergency respon­ders, physi­cians, house­keeping personnel, health care secre­tarial staff, etc).
  • Employers must ensure that appro­priate protec­tion and safety measures are in place to provide a safe workplace environ­ment for nurses and health care workers.
  • Employers must ensure that influenza vaccines are avail­able and offered to every health care worker annually at conve­nient times and locations. The employer must not discrim­i­nate against or disci­pline nurses for the appro­priate use of sick time.
  • If a decli­na­tion form is required for vacci­na­tion, the nurse must be able to sign the form confi­den­tially; that is, the nurse must not be required to divulge personal health infor­ma­tion or declare the reason(s) for refusal of a vaccine. The employer must not discrim­i­nate against or disci­pline a nurse for opting out.
  • The employer must comply with CDC and OSHA Guide­lines must be used for preven­tion, protec­tion, and safety of nurses and patients.