This year’s flu vaccine packs a rather light punch

January 25, 2017 - 06:20

The vaccine reduces the risk of catching influenza by just 28 percent amongst persons over 65, according to Swedish figures.

Mortality rates from flu are higher in years like this when the A(H3N2) variant virus dominates over other types of flu, according to the Norwegian Institute of Public Health. (Photo: Håkon Mosvold Larsen / NTB scanpix)

Many people are currently at home from work or school with fevers, coughs and runny noses. Some might be thinking: “I took a flu shot. So why am I sick?”

The primary flu virus of the 2016/2017 winter season in the northern hemisphere is the type designated as A(H3N2), reports the Norwegian Institute of Public Health (FHI).

The flu vaccine in use this season is generally less effective against this type of virus, writes the journal Dagens Medisin, based on flu statistics in Sweden.

Persons aged 65 and up suffer tougher symptoms from the A(H3N2) virus than younger people do, and this year’s vaccine is also less effective in warding off the disease amongst people in this upper age group.

Less effective for elderly and infirm

The vaccine used in Sweden is the same as in Norway, says Senior Adviser Kjersti Rydland at FHI.

She confirms that the effect of this year’s vaccine is less than optimal.

“This year’s vaccine is in the lower echelon when it comes to protection,” shes says to the journal Dagens Medisin.

“The vaccine is not as effective on everyone and its efficacy varies with regard to age and whether a person has other health problems, such as a weaker general immunity,” she says.

For persons with underlying health problems the vaccine only gives a 24 percent better protection rate than no flu shot at all.

Among persons aged 65 and older who have contacted health personnel with flu symptoms, the protection effect is on 28 percent compared to those who are not vaccinated.

Dagens Medisin reports Stockholm health official Åke Örtqvist as saying statistics from neighbouring Finland show a similar low effect from the vaccine.

Best protection

Nevertheless, the website of the Norwegian Institute of Public Health [fhi.no] emphasises that the vaccine is still the best protection against the current flu virus.

FHI writes that the flu shot works poorer than one would expect of an influenza vaccine and warns people who are succeptable due to advanced age or health conditions to be on the alert.

“Persons in the risk category who get sick need to be extra aware of being seriously stricken by the disease, also those who take the vaccination,” says Director Siri Helene Hauge at FHI’s Department of Influenza, on the website fhi.no.

Despite its weaknesses, the vaccine reduces the chances of catching the flu and if caught the vaccine can help mollify the impact of the virus.

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Read the Norwegian version of this article at forskning.no

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Translated by
Glenn Ostling