Studies published in Environmental Bioinformatics and F1000Research have indicated that COVID-19 has a seasonal pattern, due to global change and genetics, respectively.
Both studies were authored by Gustavo Caetano-Anollés, professor in crop sciences and affiliate of Carl R. Woese Institute for Genomic Biology. In the former:
Caetano-Anollés and co-author Nicolas Hernandez showed that correlations between COVID-19 metrics (new cases and deaths, total cases and deaths) and temperature and latitude strengthened during cooler months and at higher latitudes.
They also found that countries that were proactive in reducing emissions had fewer COVID cases and deaths.
In the latter:
Caetano-Anollés teamed up with doctoral student Tre Tomaszewski in the School of Information Sciences at U of I to analyze sequences of more than 12 million SARS-CoV-2 genomes between the start of the pandemic and late July 2022. They watched in a time-series analysis as more than 180,000 mutations appeared, coalesced, persisted, and/or died away across three major variants of concern (VOCs), Alpha, Delta, and Omicron.
Some of these mutations were affected by latitude, and were not as prominent in tropical climates as they were in temperate ones.
You can read more about the respective studies and their findings on the College of ACES website.