{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,14]],"date-time":"2026-02-14T09:19:39Z","timestamp":1771060779823,"version":"3.50.1"},"reference-count":49,"publisher":"MDPI AG","issue":"20","license":[{"start":{"date-parts":[[2022,10,17]],"date-time":"2022-10-17T00:00:00Z","timestamp":1665964800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"ACCC Flagship","award":["337552"],"award-info":[{"award-number":["337552"]}]},{"name":"ACCC Flagship","award":["820655"],"award-info":[{"award-number":["820655"]}]},{"name":"EXHAUSTION project","award":["337552"],"award-info":[{"award-number":["337552"]}]},{"name":"EXHAUSTION project","award":["820655"],"award-info":[{"award-number":["820655"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJERPH"],"abstract":"<jats:p>We modelled the impact of selected meteorological factors on the daily number of new cases of the coronavirus disease 2019 (COVID-19) at the Hospital District of Helsinki and Uusimaa in southern Finland from August 2020 until May 2021. We applied a DLNM (distributed lag non-linear model) with and without various environmental and non-environmental confounding factors. The relationship between the daily mean temperature or absolute humidity and COVID-19 morbidity shows a non-linear dependency, with increased incidence of COVID-19 at low temperatures between 0 to \u221210 \u00b0C or at low absolute humidity (AH) values below 6 g\/m3. However, the outcomes need to be interpreted with caution, because the associations found may be valid only for the study period in 2020\u20132021. Longer study periods are needed to investigate whether severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has a seasonal pattern similar such as influenza and other viral respiratory infections. The influence of other non-environmental factors such as various mitigation measures are important to consider in future studies. Knowledge about associations between meteorological factors and COVID-19 can be useful information for policy makers and the education and health sector to predict and prepare for epidemic waves in the coming winters.<\/jats:p>","DOI":"10.3390\/ijerph192013398","type":"journal-article","created":{"date-parts":[[2022,10,17]],"date-time":"2022-10-17T21:11:51Z","timestamp":1666041111000},"page":"13398","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":4,"title":["Impact of Selected Meteorological Factors on COVID-19 Incidence in Southern Finland during 2020\u20132021"],"prefix":"10.3390","volume":"19","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-1621-9691","authenticated-orcid":false,"given":"Lisa","family":"Haga","sequence":"first","affiliation":[{"name":"Finnish Meteorological Institute, Meteorological and Marine Research Programme, Weather and Climate Change Impact Research, P.O. Box 503, 00101 Helsinki, Finland"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Reija","family":"Ruuhela","sequence":"additional","affiliation":[{"name":"Finnish Meteorological Institute, Meteorological and Marine Research Programme, Weather and Climate Change Impact Research, P.O. Box 503, 00101 Helsinki, Finland"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Kari","family":"Auranen","sequence":"additional","affiliation":[{"name":"The Center of Statistics, University of Turku, 20500 Turku, Finland"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2840-1132","authenticated-orcid":false,"given":"Kaisa","family":"Lakkala","sequence":"additional","affiliation":[{"name":"Finnish Meteorological Institute, Space and Earth Observation Centre, Earth Observation Research, P.O. Box 503, 00101 Helsinki, Finland"},{"name":"Finnish Meteorological Institute, Climate Research Programme, Atmospheric Research Center of Eastern Finland, P.O. Box 503, 00101 Helsinki, Finland"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Anu","family":"Heikkil\u00e4","sequence":"additional","affiliation":[{"name":"Finnish Meteorological Institute, Climate Research Programme, Atmospheric Research Center of Eastern Finland, P.O. Box 503, 00101 Helsinki, Finland"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Hilppa","family":"Gregow","sequence":"additional","affiliation":[{"name":"Finnish Meteorological Institute, Meteorological and Marine Research Programme, Weather and Climate Change Impact Research, P.O. Box 503, 00101 Helsinki, Finland"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2022,10,17]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"3243","DOI":"10.1073\/pnas.0806852106","article-title":"Absolute Humidity Modulates Influenza Survival, Transmission, and Seasonality","volume":"106","author":"Shaman","year":"2009","journal-title":"Proc. Natl. Acad. Sci. USA"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"14","DOI":"10.1128\/JVI.03544-13","article-title":"Roles of Humidity and Temperature in Shaping Influenza Seasonality","volume":"88","author":"Lowen","year":"2014","journal-title":"J. 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