Europe is facing a “tridemic” that threatens to push health systems to the limit as a surge in flu cases is compounded by Covid-19 and other respiratory illnesses.
Spain and Italy are among the countries worst affected as hospitals struggle to cope with an influx of patients and coronavirus-era mask mandates are reintroduced in health facilities in some regions.
Upticks in cases have also been reported in Germany, where the public health authority said a flu wave officially began on December 11, and in France, where 10 out of 18 regions are officially in an epidemic phase. In the UK, there has been a slight rise in flu cases and hospitalisations, with officials warning that the peak was yet to come.
In Spain, Christmas superspreader events led to an increase in flu cases by 75 per cent in the final week of 2023, according to data from the state-backed Carlos III Health Institute. Reports of flu leading to severe pneumonia are proliferating.
Nearly half of all flu tests in Spain came back positive in the last week of December versus 27 per cent in the previous seven days. Covid-19 cases stabilised with only 10 per cent of tests positive at the end of 2023, but the virus was causing a rising number of hospital admissions, especially among people over 80, the Carlos III institute said.
Children, meanwhile, were coming down with respiratory syncytial virus, which can cause bronchiolitis and has led to a sharp rise in hospitalisations of infants aged under one.
The mix of flu, Covid and RSV cast a shadow over a European festive season punctuated by coughs, colds and people bowing out of celebrations because they felt too unwell. Those who made it were met with conversations about who was vaccinated against flu and whether it was too late to get a jab.
By Saturday, three Spanish regions — Catalonia, Valencia and Murcia — had made mask-wearing mandatory at health facilities. Mónica García, Spain’s health minister, has convened a meeting of regional health chiefs on Monday to discuss extending the obligation across the country.
García said on Friday that the rise in illness would “intensify” in the coming days and called on people to exercise caution at large indoor gatherings and health facilities. “In short, we appeal to common sense and ask for the same resilient spirit that people demonstrated during the pandemic,” she said.
CSIF, a Spanish union whose members include health professionals, has warned that some hospitals are at saturation point. In addition to obligatory mask-wearing at health facilities, it has called for special ventilation measures and for people to exercise prudence in deciding whether they need to see a doctor.
A similar trend was registered in Italy, where an estimated 2mn people came down with flu, Covid and RSV in the last two weeks of 2023, according to the Italian National Institute of Health. The spike in cases added to pressure on hospitals and emergency rooms which are struggling with a chronic shortage of beds and staff.
Non-urgent surgery has been delayed as a consequence, with over 1,000 patients in the Rome region waiting to be moved from emergency rooms to wards, according to the Italian Society of Emergency Medicine.
Roberto Cosentini, head of the emergency room at Bergamo Hospital in northern Italy, told the Financial Times that the combination of respiratory viruses and Christmas holidays had produced a “perfect storm”, with many young people and children needing hospital treatment.
“This year’s flu was quite virulent, especially on the respiratory system, even on young people. We had to hospitalise more people with complications due to flu than usual.” Cosentini said the first days of 2024 were the worst, when his hospital had to rush to add doctors and nurses and create new wards “because there were too many sick people”.
The European Centre for Disease Prevention and Control warned last month that respiratory infections would be higher than usual this winter because of lower immunity levels after the anti-Covid measures of recent years had led to an overall reduction in such cases.
It told national governments to increase vaccination rates for Covid and influenza and boost emergency department capacity, as well as to encourage handwashing and mask-wearing for the most vulnerable.
José María Molero of the infectious diseases team at the Spanish Society of Family and Community Medicine said the term “tridemic” should not be taken to mean that individuals were catching multiple viruses but rather that they were suffering from one of the three diseases. “There are very few cases of co-infection,” Molero said.
The UK has yet to experience a major flu surge this winter.
Data for the last week of 2023 in Britain showed a slight uptick in the percentage of people who tested positive for flu, according to lab samples: it rose to 11.8 per cent from 11.2 per cent in the previous week. Influenza hospitalisations increased to 6.8 per 100,000 from 5.1 per 100,000 last week and admissions to intensive care and high dependency units increased week-on-week but remained low.
There was also a slight reduction in consultations with primary care staff for flu-like illness. Mary Ramsay, director of public health programmes at the UK Health Security Agency, warned: “The winter peak for flu is still to come and may coincide with high levels of Covid-19.”
Additional reporting by Sarah White in Paris, Guy Chazan in Berlin and Sarah Neville in London