Epidemiology of Seasonal Coronaviruses: Establishing the Context for the Emergence of Coronavirus Disease 2019

Abstract

Public health preparedness for coronavirus (CoV) disease 2019 (COVID-19) is challenging in the absence of setting-specific epidemiological data. Here we describe the epidemiology of seasonal CoVs (sCoVs) and other cocirculating viruses in the West of Scotland, United Kingdom. We analyzed routine diagnostic data for >70 000 episodes of respiratory illness tested molecularly for multiple respiratory viruses between 2005 and 2017. Statistical associations with patient age and sex differed between CoV-229E, CoV-OC43, and CoV-NL63. Furthermore, the timing and magnitude of sCoV outbreaks did not occur concurrently, and coinfections were not reported. With respect to other cocirculating respiratory viruses, we found evidence of positive, rather than negative, interactions with sCoVs. These findings highlight the importance of considering cocirculating viruses in the differential diagnosis of COVID-19. Further work is needed to establish the occurrence/degree of cross-protective immunity conferred across sCoVs and with COVID-19, as well as the role of viral coinfection in COVID-19 disease severity.

Different pattern of pre-existing SARS-COV-2 specific T cell immunity in SARS-recovered and uninfected individuals

“…Six other coronaviruses are known to infect human. Four of them are endemically transmitted 5 and cause common cold (OC43, HKU1, 229E and NL63), while SARS-CoV (defined from now as SARS-CoV-1) and MERS-CoV have caused limited epidemics of severe pneumonia 6 . All of them trigger antibody and T cell responses in infected patients: however, antibody levels appear to wane relatively quicker than T cells.…”

Breadth and function of antibody response to acute SARS-CoV-2 infection in humans

“…Cross-reactivity among betacoronaviruses has also been reported in polyclonal sera (21,22). Human coronavirus OC43, discovered in the 1960s, is one of the major betacoronaviruses that cause common colds in the community (23,24), and severe respiratory infections in elderly and immunocompromised individuals (22,25). Epidemiologic surveys reveal that OC43 infection can occur in early childhood, and that OC43 seropositivity reaches nearly 90% in adults (26,27).…”

No SARS-CoV-2 cross-neutralization by intravenous immunoglobulins produced from plasma collected before the 2020 pandemic

“…Recovered plasma is usually obtained from elder donors. A trend towards increasing probability of hCoV-229E infections with age was detected in the Scottish [3] and US [4] population. Furthermore, higher hCoV-229E specific nAb titers were found in older study participants (60-85 years) compared to younger ones (21-40 years) [10].…”

“…The virus belongs to the Coronaviridae family of viruses which contains several species of importance for human health. The human coronaviruses (hCoVs) 229E, NL63, OC43, and HKU1 are in circulation as seasonal respiratory viruses that mostly cause self-limiting and mild infections but which can also lead to pneumonia and bronchiolitis [2][3][4] Due to the widespread and long-term circulation of hCoVs, and the pooling of plasma from thousands of donors for every lot of IVIG, it was shown that IVIGs contain significant levels of hCoV nAb levels, as was shown for example for hCoV-NL63 [5]. Whether these hCoV antibodies cross-react with or even neutralize the related SARS-CoV-2 has not been fully elucidated.…”