Leaving no stone unturned in light of the COVID-19 faecal-oral hypothesis? A water, sanitation and hygiene (WASH) perspective targeting low-income countries
Author
Gwenzi, Willis
Institutions
Abstract
The human coronavirus disease (COVID-19) is now a global pandemic. Social
distancing, hand hygiene and the use of personal protective equipment dominate the current fight
against COVID-19. In developing countries, the need for clean water provision, sanitation and
hygiene have only received limited attention. The current perspective examines the latest
evidence, on the occurrence, persistence and faecal-oral transmission of severe acute respiratory
syndrome coronavirus-2 (SARS-CoV-2), the etiological agent for COVID-19. Evidence shows
that SARS-CoV-2 proliferate in the human gastrointestinal system, and is shed via faeces.
SARS-CoV-2 can survive and remain viable for up to 6 to 9 days on surfaces. Recent
wastewater-based epidemiological studies from several countries also detected SARS-CoV-2
RNA in raw wastewaters. Shell disorder analysis show that SARS-CoV-2 has a rigid outer shell
conferring resilience, and a low shell disorder conferring moderate potential for faecal-oral
transmission. Taken together, these findings point to potential faecal-oral transmission of SARS-CoV-2, which may partly explain its rapid transmission. Three potential mechanisms may
account for SARS-CoV-2 faecal-oral transmission: (1) untreated contaminated drinking water,
(2) raw and poorly cooked marine and aquatic foods from contaminated sources, and also raw
wastewater-based irrigation (e.g., salads) and aquaculture, and (3) vector-mediated transmission
from faecal sources to foods, particularly those from open markets and street vending. SARSCoV-2 faecal-oral transmission could be particularly high in developing countries due to several
risk factors, including; (1) poor drinking water, wastewater and sanitation infrastructure, (2) poor
hygiene and food handling practices, (3) unhygienic and rudimentary funeral practices, including
home burials close to drinking water sources, and (4) poor social and health care systems with
low capacity to cope with disease outbreaks. Hence, clean drinking water provision, proper
sanitation, food safety and hygiene could be critical in the current fight against COVID-19.
Future research directions on COVID-19 faecal-oral transmission are highlighted.