It May Be Seasonal Like Flu

February 05, 2021

A new research estimating the disease potential of the covid virus in different regions worldwide points out that the virus may be seasonal, like other respiratory viruses such as flu.

A new research by the University of Illinois estimating the disease potential of the SARS-CoV-2 virus in different regions worldwide points out that the virus may be seasonal, just like other respiratory viruses such as flu.

The paper – entitled, “Temperature and Latitude Correlate with SARS-CoV-2 Epidemiological Variables but not with Genomic Change Worldwide”, peer-reviewed and published in “Evolutionary Bioinformatics” – found that the epidemiological trends observed worldwide suggest a seasonal effect for the disease that is not directly controlled by the genomic makeup of the covid virus.

“This study”, authors write, “aims to understand the disease potential of the virus in different regions by studying how average spring temperature and its strong predictor, latitude, affect epidemiological variables such as disease incidence, mortality, recovery cases, active cases, testing rate, and hospitalization. We also seek to understand the association of temperature and geographic coordinates with viral genomics.” … “Our worldwide epidemiological analysis showed a significant correlation between temperature and incidence, mortality, recovery cases and active cases.”

Researchers affirm: “The WHO suggests disease incidence, mortality, recovery rate and number of active cases are properties related to onset of the infection. However, both mortality and recovery rate are more dependent on the organism’s immune system, which suggests that patients from regions with high temperatures are also more resistant to the virus.”

“Other biological factors can also be relevant. Low-temperature seasons are often associated with vitamin D deficiency because of seasonal reductions in exposure to ultra-violet (UV) radiation. Low levels of vitamin D have been shown to impair the body’s antimicrobial peptide system, which is responsible for regulating the immune response. Seasonal changes in length of day can interfere with an individual’s circadian rhythm, which is regulated by the release of the hormone melatonin. This interference can weaken the immune system and increase the risk of infection.”

“Changes in photoperiod and sunlight exposure have been used to explain the observed latitudinal migration of influenza activity during the winter season. As observed with influenza infection latitudinal belts, lower temperatures are associated with increases in morbidity and mortality. Thus, the interaction of the environment with covid-19 epidemiological data is important and merits further study.” Study concludes: “The epidemiological trends we observed worldwide suggest a seasonal effect for the disease that is not directly controlled by the genomic makeup of the virus. Future studies will need to determine if correlations are more likely the result of effects associated with the environment or the innate immunity of the host.”

Full Study “Temperature and Latitude Correlate with SARS-CoV-2 Epidemiological Variables but not with Genomic Change Worldwide”