The CDC recommends preparing for a “potentially severe” flu season

This year’s flu season could be very severe as flu virus strains not fully covered by this year’s vaccines are predicted to predominate.

Nevertheless, recommendations are for the population to be vaccinated against influenza, especially those at the highest risk of complications.

Such a message was published today by the US Center for Disease Control and Prevention /CDC/. It strongly recommends that those “vaccinated against influenza should be vaccinated this season” and that “antiviral therapy be started as soon as possible in people at risk of complications, in appearance of the first flu symptoms.”

On the web page of the European Center for Disease Control and Prevention there is a published message dated 04.12.2014 about an outbreak of measles related to an international dog show in Slovenia /MIK/. The infectious disease outbreak was probably due to exposure during the MIC.

15 cases of measles were registered in November /11 confirmed and 4 probable/, all of whom visited the exhibition held in Vrtojba, near Nova Gorica on November 8 and 9, 2014

According to the data of the epidemiological services in the USA, this year the strains of the influenza virus type A /H3N2/, known in Bulgaria as Perth, will be the most common. This virus is genetically different from the strains used to create this season’s vaccine.

Seasonal flu vaccines are designed to protect against 3 or 4 different flu viruses. But the CDC notes that the vaccine released this year only partially protects against one of the strains.

From there, however, they emphasize that the protection against the other viruses is complete and it is entirely possible that these infectious organisms will prevail by the end of the season.

The reason this year’s flu vaccine doesn’t cover all the major strains in full is that it takes much less time for the flu virus to mutate than it does to make a vaccine.

Predicting what strains will predominate in a particular season is similar to weather forecasting, but over a long period of time – there is always the possibility that things can change dramatically.

This does not happen every year, but sometimes the small changes in the genome of the virus, after accumulating for several months, cause it to suddenly and unpredictably change its properties, despite the scientists’ predictions.< /p>

This year, in mid-February, the World Health Organization /WHO/ published recommendations for vaccine production for the 2014-2015 flu season in the Northern Hemisphere.

Immediately after that, the vaccine production cycle began, which takes 6 months. During this period, millions of doses of the antiviral drug should have been released to the market.

At the same time, the rate of drift /accumulation of point mutations/ in H3N2 viruses was found in only a few samples, out of thousands collected by WHO scientists.

H3N2 type viruses were the most common and, according to the experience of the previous season, they were the cause of the most severe course of the flu and most often require hospitalization when infected.

In the 2012-13, 2007-08 and 2003-04 seasons, it was H3N2 influenza viruses that dominated. During these 3 seasons, it was these influenza strains that were registered highest death rate for the last decade.

Currently, research shows that of all H3N2 influenza viruses, half are “drift” strains, meaning that the vaccine’s protective effect will be weakened.

This still does not make its action useless for the vaccinated, but the protection provided will be weaker than it would be in the absence of a deviation in the genes of the viruses.

Vaccinated people when in contact with the modified pathogens will get sick, but the viral infection will be milder in them compared to unvaccinated people.

CDC Director Tom Frieden said that it is too early to say that the upcoming flu season will be severe, but we must be prepared because there are prerequisites for such a development of the situation.

Dr. Frieden emphasizes that the flu season is just getting started and it’s not too late to go and get vaccinated.

The CDC director also notes that there are three effective ways to reduce flu mortality.

The first is to vaccinate people, the second is to give antiviral treatment to people in the group at high risk of complications without waiting and the third is to keep sick people at home until they get better completely so as not to infect other people.

The CDC recommends that everyone 6 months of age and older, with rare exceptions, get a seasonal flu shot every fall.

This is especially important for people in the group at highest risk of flu complications: children under 5 years of age, the elderly over 65, and those with certain illnesses such as asthma, diabetes, chronic kidney disease, or with heart and lung diseases. Vaccination against seasonal flu is also strongly recommended for pregnant women.

CDC recommends that people at highest risk seek medical attention at the first characteristic flu symptoms, which are usually sore throat and body, runny nose, stuffy nose, headache, chills, and general weakness .
There is convincing scientific evidence that antiviral preparations are most effective for influenza if their intake begins within the first 48 hours after the influenza virus enters the body and the first symptoms appear.

It should be noted that after the death of four people /two women and two men aged between 67 and 87 years / the Italian Agency for the Evaluation of Medicinal Products suspended the use of two lots of flu vaccines developed by the Swiss pharmaceutical company Novartis. The FLUAD vaccine was approved back in 1997 and is intended for elderly people.