Protective Effect of Food Against Inactivation of Human Coronavirus OC43 by Gastrointestinal Fluids

Abstract

The involvement of the gastrointestinal (GI) tract in severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection has been reported in multiple studies. Since it has been demonstrated that human intestinal epithelial cells support productive viral replication and that a substantial portion of infected individuals shed the virus in feces, the possibility of fecal–oral and fecal-respiratory modes of transmission have been proposed for SARS-CoV-2. In order to establish viral replication in the intestine, enteric viruses need to retain their infectivity in often low pH gastric fluids, and in intestinal fluids, which contain digestive enzymes and bile salts. In this study, we examined whether human coronaviruses OC43 (HCoV-OC43) can remain infectious in simulated GI fluids that models human fasting-state and fed-state, in the presence or absence of food. We demonstrated that except for fasting-state gastric fluid (pH 1.6), the virus can remain infectious in all other gastrointestinal fluids for 1 h. Furthermore, we demonstrated that presence of food could significantly improve viral survival in gastric fluids. Therefore, this study provides evidence that ingestion with food could protect the virus against inactivation by the GI fluids.

Effectiveness of neutral electrolyzed water in inactivating HCoV-OC43 and SARS-CoV-2 on the surfaces of plastic and the medicinal plant Centella asiatica (L.) urban

“…Water is commonly present on the surface of raw plant materials. Furthermore, HCoV-OC43 can remain infectious in simulated gastrointestinal fluids during feeding, and food may increase its stability ( Harlow et al, 2022 ). In this study, water showed no or low antiviral activity against dried HCoV-OC43 compared with NEW.…”

Survival of human coronavirus 229E at different temperatures on various food-contact surfaces and food and under simulated digestive conditions

“…A previous study also demonstrated that the infectivity of SARS-CoV-2 and HCoV-229E was maintained in FaSSIF but lost in FeSSIF containing bile salt ( Lee et al, 2020 , Zhou et al, 2017 ). Other studies showed that HCoV-OC43 and MERS-CoV were resistant to FaSSIF and FeSSIF ( Harlow et al, 2022 , Zhou et al, 2017 ). In another study, residual SARS-CoV-2 mNeonGreen reporter virus was present after 1 h of treatment with simulated small intestinal fluid ( Zang et al, 2020 ).…”

“…HCoV-OC43 survived at all FeSSGF pHs as in this study. Additionally, the presence of food (cucumber) in FeSSGF significantly increased the survival of HCoV-OC43 ( Harlow et al, 2022 ). This study showed that HCoV-229E maintained its infectivity in FaSSIF (pH 7), whereas the virus was inactivated in FeSSIF (pH 5) containing pancreatin.…”

“…In addition, some patients with GI symptoms have been reported to have higher pH values in their stomach, indicating that the virus may survive gastric conditions and bind to angiotensin converting-enzyme 2 (ACE2), which is predominantly expressed in pulmonary epithelial cells, as well as in the duodenum and small intestine ( Hikmet et al, 2020 ). ACE2 is the main receptor for SARS-CoV-2 binding to target cells ( Harlow et al, 2022 ). The virus is then processed to release viral contents into the host cell cytosol ( Hoffmann et al, 2020 ).…”

Efficacy of washing produce in removing human coronavirus OC43 and murine norovirus

“…The concentration of infectious viral particles for HCoV‐OC43 was determined by TCID 50 using MRC‐5 cells as described previously (Harlow, et al 2022). A negative control consisting of MEM maintenance media and a positive control consisting of diluted HCoV‐OC43 stock, were also included.…”