The study published in the journal Nature npj Clean Water reports water bodies influence by treated or untreated wastewater are likely not associated with the spread of COVID-19. The paper’s authors include distinguished Internal Water Association Fellow Dr. Charles Haas.
The challenges posed by COVID-19 require many diverse fields of research engagement to address. Understanding risks relating to exposure of the infectious agent, SARS-CoV-2, is key among them. Kumar et al. have assembled relevant literature with the aim of developing a risk assessment for recreators using bodies of natural water. However, the authors have introduced a number of shortcomings into their analysis, which in our opinion results in a substantial overestimate of the underlying risks of exposure and infection. We briefly discuss them below.
Despite prolonged SARS-CoV-2 RNA detection in the stool of infected and convalescent patients1, observations of intact virions2 and evidence of virion infectivity in stool are sparse3. In nasopharyngeal clinical specimens, RNA is found to be more persistent (median duration 34 days) compared to culturable virus4 (median duration 7 days), thus establishing that observations of SARS-CoV-2 RNA alone are not sufficient to confirm the presence of infectious virus.
it is likely that the risks of SARS-CoV-2 infection associated with recreational exposures to waters under the influence of treated wastewater (if any) are orders of magnitude below those estimated by Kumar et al. despite their assertion that “the estimated chance of infection for COVID-19 in this study could be underestimated.” Thus, it is unsurprising that, to our knowledge, no cases of COVID-19 have been linked to such exposures. We would also note that further work is needed in the contexts of unsewered areas, lower and middle income countries with uncontrolled waste management, and open defecation7.
My Profile
