Experts agree that we will live with Covid-19, as well as other flu syndromes. The tendency is for the disease to become endemic, that is, it occurs regularly and has some peak periods. Doctors call this seasonality.
To try to identify the seasonality of SARS-CoV-2 — the virus that causes the disease —, researchers from the Yale School of Public Health (YSPH) and the University of North Carolina at Charlotte analyzed the behavior of similar viruses. The study was published by mBio.
- To predict the seasonality of the SARS-CoV-2 virus, scientists used historical data from different coronaviruses with known seasonal patterns.
- Monthly data on infection by different coronaviruses in previous studies in Europe, East Asia and North America were analyzed. The viral samples are from 1985 and 2020.
- The discovery was that SARS-CoV-2 tends to increase in the colder months, especially in temperate locations in the Northern Hemisphere, and decrease in the summer. This period may change depending on the region.
- According to forecasts, in Rochester, Minnesota, the incidence will peak in December, remaining that way until the end of spring.
- In Edinburgh, United Kingdom, the increase begins more gradually in autumn and decreases in mid-spring.
- The predictions only apply when Covid-19 becomes endemic — something experts are still unsure about when it will happen.
The importance of knowing the seasonality of a disease
Knowing when a disease will occur most often helps hospitals prepare to care for a large number of patients. This way, it is possible to prevent health systems from becoming overloaded. Jeffrey Townsend, first author of the study, explained to the Medical Express portal that forecasts are important for the health sector and explains which periods require attention:
Having some idea of when we will see peaks in the future is important for public health policy and decision-making. Late autumn, winter and early spring are the highest risk periods for infection outbreaks.
Jeffrey Townsend for Medical Express