First evidence of tropical seasonality of coronavirus HCoV-OC43 in response to climate change in Córdoba, Argentina

Abstract

HCoV-OC43 causes acute upper and lower respiratory infections and is an important cause of morbidity and mortality globally in children under 4 years of age. It has a varied clinical picture, in mono and co-infection that prevails in autumn-winter like other respiratory agents. Circulation, classical/molecular epidemiology and seasonality of HCoV-OC43 and the relationship with other respiratory agents were determined in children aged 1 month to 14 years with low ARI, hospitalized at the Municipal Children's Hospital (HIM) of Córdoba.

It was an annual and descriptive study on 1,053 respiratory samples from 1/07/2018 to 30/06/2019. The panel of 8 routine respiratory viruses was detected by Immunofluorescence (IF) Kit from Millipore U.S.A., in the HIM and in the Virological HCoV-OC43 was detected by One Step RT-PCR according to protocol of Vabret et al. (2001) whose primer amplifies viral M protein. This strategy complemented both methodologies, which were not compared, but completed the study.

The overall prevalence of respiratory agents was high at 77.86 % per FI, with a prevalence of 5.41 % for HCoV-OC43 including mono and BM co-infections also high, although this does not allow comparison. Cases predominated in children 2 years of age, male, with mild clinical symptoms such as colds, catarrh and more severe ones such as bronchial obstructive syndrome, bronchiolitis and asthma. In addition, the seasonality presented when analyzing temperature, precipitation and humidity, with respect to the characteristic behavior of these respiratory agents, was noteworthy. There was a high number of cases of HCoV-OC43 in monoinfection in summer, as a new finding, suggesting a lack of seasonality as a consequence of anthropic behavior within the Model of Appropriation of Nature that explains part of the climate change.

This research provides a valuable methodological tool for the health of the community, completing the differential diagnosis, the appropriate treatment and providing strategies for public health in the region. It is also a concrete scientific contribution to the knowledge of the variability or non-seasonality of HCoV-OC43 that has been occurring for decades and encourages us, as a future perspective, to continue and expand our knowledge of this agent and other respiratory viruses.