Fever and chills have arrived

This year’s flu wave started in Western Switzerland, and has now reached Central Switzerland. The age group of over 65-year-olds is less affected this year, however, for two reasons.

High fever and chills, cough, sore throat, headache and joint pain are suddenly with us again. Every winter - sometimes earlier, sometimes later - the viral disease in Switzerland becomes an epidemic. According to the Federal Office of Public Health (BAG), this definition requires a threshold of “flu-like diseases” to be met. The level of 69 cases per 100,000 inhabitants was exceeded in Central Switzerland in the second week of January, as figures from the BAG show.

Up to now, the flu wave has been similar to the previous year (see illustration 2). Sonja Bertschy, deputy chief physician for infectiology and hospital hygiene at the Lucerne Cantonal Hospital (Luks), says: “Making forecasts for the further development is like reading coffee grounds”.

Experience has shown that each flu season is different. 80 flu cases have been registered in the Luks since the beginning of the year. The only thing that can be said at the moment is that the flu wave will start a little later this year than in previous years.

Photo 1: An important tip: hold a handkerchief over your mouth and nose when coughing and sneezing.
Illustration: Influenza wave passes epidemic level – report per 100,000 inhabitants / Threshold level = 69

The flu wave appeared in West Switzerland earlier than in Central Switzerland. This is a phenomenon that is often be observed, says Christoph Merlo, who runs a group practice on Furrengasse in Lucerne. The reasons for this are unclear. Dr. Merlo has been head of Sentinella Doctors in Central Switzerland from 2000. They are part of a reporting system, and send observations to the BAG anonymously every week.

He has only seen isolated flu cases in his practice this season, says Merlo. "There are usually fewer illnesses in our practice, however, because our patients are older on average." This pattern is confirmed by nationwide figures. Most new cases currently occur in the age group of 0- to 14-year-olds, while the value is lowest among those over 65 years of age. Merlo sees two reasons for this: “Older people vaccinate themselves more consistently. In addition, they have experienced various flu epidemics in the course of their lives, which is why they have been able to build up a certain basic immunity. This comes into play, although the flu viruses change slightly from year to year.”

The risk of serious complications is increased if infection occurs in the elderly, however. Sore throats, pneumonia or otitis media can result.

It’s possible to use vaccination to protect against influenza, as the flu is called in technical jargon. The vaccines are adjusted annually based on the viruses from the previous year. Depending on the season and people vaccinated, the effectiveness is estimated at 20 to 80 percent. And how is it this year? Merlo is optimistic: “So far, the vaccinations are working."

And further: "It is advantageous that a tetra vaccine is now used nationwide." This protects against two virus strains of influenza: type A and type B. "There were problems in the previous two years because some of the vaccines were only effective against one of the two Influenza type B viruses. Most doctors and institutions have now switched. “Significantly more type A viruses have been detected this year, which are well covered in the active ingredient”.

The ideal period for vaccination is from mid-October to mid-November. But vaccination is still possible: "It is certainly a little late, but not too late, because the flu is only now rolling in," says Sonja Bertschy. It takes around 10 to 14 days for full protection to develop. In addition to vaccination, the BAG recommends washing your hands thoroughly with soap and water and holding a tissue in front of your mouth and nose when coughing or sneezing.