The «Tri-epidemic» of influenza, RSV, COVID concerns experts

Influenza, RSV and SARS-CoV-2. Three respiratory viruses, which are transmitted in the same way and tend to show an increase in cases during the winter months. Their simultaneous occurrence is of concern to scientists, as both children and adults have had less contact with each other over the past 2 seasons and therefore lack the natural immunity this year against influenza (influenza) and syncytial virus (RSV) that was seen before the outbreak of the COVID-19 pandemic.

The doctors of the Therapeutic Clinic of the Medical School of the National and Kapodistrian University of Athens Theodora Psaltopoulou, Rodanthi Eleni Syrigou, Yannis Danasis, Panos Malandrakis, and Thanos Dimopoulos (Dean of the University of Athens) summarize the data of a recent publication on «tri-diamonia» in the scientific journal WebMD.

Flu season has started early and since October 21, early increases in seasonal flu activity have been reported across most of the United States, according to the Centers for Disease Control (CDC). At the same time, Children's Hospitals across the United States are reporting increased cases suffering from RSV.

University of North Carolina Professor of Epidemiology Justin Lessler says it is difficult to predict the exact month of the flu outbreak. For SARS-CoV-2, some epidemiological models predict some spikes before Christmas and others predict a new wave in 2023. For influenza, the model predicts an earlier than usual onset. While flu activity is relatively low the season has started early, according to CDC data. For the week ending October 21, 1,674 patients were hospitalized for influenza, a higher number than in the summer months but lower than the 2,675 hospitalizations for the week of May 15, 2022. Meanwhile, new Covid-19 illnesses decreased by 12% in the last two weeks, while RSV was at 15% compared to 11% in 2021.

As Timothy Brewer, professor of medicine and epidemiology at UCLA, reports, the number of deaths from childhood flu typically ranges from 37 to 199 per year, according to CDC records. But in 2020-2021, the CDC recorded one pediatric flu death in the U.S. Because of pandemic containment measures, the population lacks natural immunity against influenza and RSV.

RSV can be a risk for anyone, as there is no vaccine, but the greatest risk is for children under 5 years of age, especially infants under 1 year old, and adults over 65 years of age. Symptoms include runny nose, reduced appetite, coughing, sneezing, fever and wheezing. But in young infants, there may only be reduced activity, irritability and breathing problems. The symptoms of flu, SARS-CoV-2 and RSV may overlap. But each can include respiratory problems, which can drive vulnerable populations to the hospital.

Timothy Brewer states that to avoid «tri-demic» or any other infection, in case of symptoms, it is recommended to stay at home and to use personal protective measures, both for the better recovery of the patients, but also to avoid contagiousness and spread in the environment of each patient and, by extension, in the wider population.