The flu epidemic in Europe is intense and expected to peak in early January. This surge, which is overwhelming emergency departments and at times prompting authorities to requisition physicians, is occurring across much of Europe, the World Health Organization (WHO) said.

The flu season “has begun roughly 4 weeks earlier than in previous seasons,” the WHO noted. At least 27 of the 38 countries in the WHO European Region are now seeing high or very high influenza activity. In six countries — Ireland, Kyrgyzstan, Montenegro, Serbia, Slovenia, and the United Kingdom — more than half of patients tested for influenza-like illness were positive for influenza.”

A New Strain

“A newly dominant virus strain is placing health systems under significant pressure in some countries,” the WHO said.

“The flu comes around every winter, but this year is a little different,” said Hans Henri P. Kluge, WHO Regional Director for Europe. “A new strain — A(H3N2) subclade K — is driving infections, though there is no evidence that it causes more severe disease. This new variant of seasonal flu now accounts for up to 90% of all confirmed influenza cases in the European Region. It shows how even a small genetic variation in the flu virus can place enormous pressure on our health systems because people do not have built-up immunity against it.”

A similar picture is being observed in France, according to Santé publique France and the Institut Pasteur.

“The influenza virus detected most frequently is type A, known for its virulence. We are finding several subtypes among the samples tested: A(H3N2) subclade K and A(H1N1)pdm09,” said Vincent Enouf, deputy head of the National Reference Center for Respiratory Infection Viruses at the Institut Pasteur in Paris, France.

Is the Vaccine Effective?

While it cannot prevent all infections, early data from the UK indicate that the current seasonal flu vaccine reduces the risk for severe complications linked to A(H3N2), the WHO said.

The European Centre for Disease Prevention and Control (ECDC), the EU’s disease control agency, reported that preliminary data from a multicentre primary care study in the Vaccine Effectiveness, Burden and Impact Studies (VEBIS) programme show that seasonal vaccines available in the EU offer protection against A(H3N2) infection, with vaccine effectiveness between 52% and 57%. VEBIS is ECDC’s network assessing influenza vaccine performance in real-world primary care.

The WHO and ECDC reiterated that vaccination remains the most important preventive measure to avoid severe complications, particularly for people at high risk, including older adults, those with underlying conditions, pregnant women, and children. The WHO also encouraged health professionals to get vaccinated to protect themselves and their patients.

“The current flu season, though serious, does not represent the level of global emergency we faced during the COVID-19 pandemic,” Kluge said. “Our health systems have decades of experience managing influenza, we have safe vaccines that are updated annually, and we have a clear playbook of protective measures that work. If we use the proven tools that we already have — vaccination, health-conscious behaviour, and strong public health systems to protect the most vulnerable — then we will weather this predictable, seasonal storm.”

With the year-end holidays approaching, consistently adopting protective measures is essential to slow the spread of respiratory viruses and protect those at the highest risk for severe disease.

This story was translated from Medscape’s French edition.