Time to roll up your sleeves

The influenza (flu) virus causes extensive morbidity each year in all age groups. The flu is characterized by symptoms such as fever, coughing and muscle pains, which generally go away on their own in a few day without any complications. However, the virus sometimes leads to serious complications that can include pneumonia, perimyocarditis, meningitis and even death. The flu vaccine is the most effective way to prevent the flu. Dr. Michal Shtein, Director of the Infectious Diseases Unit at Hillel Yaffe Medical Center, responds to several common assumptions and questions about the vaccine.

Assumption: After all, the flu is a viral disease, and vaccines do not help viruses. I'll either catch it or I won't.

While the flu is a viral disease, it is more serious that the other common winter viruses and can lead to complications in the respiratory tract and in other organs, and can even result in death. The effectiveness of the vaccine depends on numerous variables, including the age and health of the person being vaccinated, and the match between the viruses used to make the vaccine and the circulating strains that season. Under optimal conditions, when the person vaccinated is a healthy adult and there is a good match between the vaccine and the circulating strain of the virus that season, the vaccine is very effective. It declines when the person vaccinated is either very young or very old, when they suffer from background diseases, and when a there is not a good match between the World Health Organization's forecast of the virus to what actually circulates in the given season. However, even in those cases, the vaccine is very effective at preventing complications and death.

Assumption: I got vaccinated last year. That's enough.

The flu virus changes from year to year, which is why you need to get vaccinated each year. The World Health Organization decides on the composition of the vaccine, based on the forecast for the virus that will be common in the season. Moreover, it is an inactivated vaccine that does not contain adjuvants (a substance that is added to the vaccine in order to create a stronger immune response), which means that the immunity it provides disappears within several months. For these reasons it is important to get vaccinated before every flu season.

Assumption: Only the elderly, babies, people with chronic diseases and pregnant women need to be vaccinated.

Most of the risk of complications is, in fact, in those groups, but it is important to know that most of the complications are found in healthy people.

Assumption: You don't die from the flu. It's just an unpleasant winter disease.

The flu is a serious disease compared to other viral diseases that lead to colds. It can definitely lead to many complications and death, even in young and healthy people.

Director General of Hillel Yaffe Medical Center, Mickey Dudkiewicz getting the flu vaccine

Assumption: The flu goes away by itself, with or without antibiotics. It doesn't require treatment.

In most case, the flu goes away on its own within about a week, but there can be complications, some from the flu virus itself and others from a secondary bacterial infection. This kind of complication sometimes requires antibiotics and even hospitalization. It is important to be vigilant about this.

Assumption: The vaccine contains live virus. Why should I introduce viruses into a healthy body.

There are two types of flu vaccine: the first is the long-standing and common vaccine, which is inactivated. It does not contain living biological material and is administered by injection. The second is a live attenuated vaccine administered as a nasal spray, which has come into use in recent years. This vaccine contains viruses that have been weakened so they cannot cause the disease, but do provide immunity which protects against the flu itself. In the past two years, the effectiveness of the live attenuated vaccine against the  H1N1 flu virus has varied, which is why this year preference has been given to the inactivated vaccine in Israel and the US.

Assumption: I always get sick after getting the flu shot. The vaccine causes the disease. Everyone knows that the flu vaccine has serious and unpleasant side effects.

The inactivated vaccine does not contain live viruses. Therefore, it cannot cause the flu. When you get the flu right after being vaccinated, you can be fairly certain that you were infected before getting the shot. Another possibility is that you were infected with a strain that was not covered by the vaccination that year.

The side effects of the inactivated virus are mild and go away on their own. The most common side effect, as with other vaccines, is a local and passing reaction at the injection site. Side effects can include not feeling well, muscle aches and the like, which may continue for 48 hours, but cannot cause complications like the disease itself. The side effects of the live attenuated vaccine are a runny or stuffy nose. Other effects such as headaches, coughing, fever and sore muscles are rarer, mild and go away within a short time. The live attenuated vaccine can exacerbate respiratory symptoms in populations at high risk of being infected with the virus, as it contains live, but weakened viruses. Therefore, patients in high-risk groups are advised not to get this vaccine. Another known concern is the occurrence of Guillain-Barré syndrome (GBS). It is important to note that since 1976, there have no recorded increases in the development of the syndrome after receiving the flu vaccine. Remember that the flu itself will cause higher rates of GBS, so there is no justification for not vaccinating against the flu out of a fear of GBS.