COVID-19 ISO Insights

Municipal Wastewater May Contain COVID-19 Clues

April 13, 2020

By: Christopher Sirota, CPCU

Although the Centers for Disease Control and Prevention (CDC) and the World Health Organization (WHO) both stress that the main path of the novel coronavirus transmission is via respiratory droplets, some researchers are looking at the outbreak from a gastrointestinal angle, and learning about another means of potential transmission and about possibly a new clue for diagnosis and epidemiological predictions: exposure to infected human stool.

Fortune reports that researchers in China have found the novel coronavirus (SARS-CoV-2) in samples of COVID-19 patient faeces, and the Chinese Center for Disease Control and Prevention now recommends:

drinking boiled water, avoiding eating raw food, implementing separate meal systems, frequent hand-washing, disinfecting toilets, and preventing water and food contamination from patients’ stool […to avoid fecal-oral transmission from contaminated hands, food, and water that can] cause infection when the microbes enter the mouth or eyes, or are inhaled

The researchers reportedly noted that rectal swabs detected COVID-19 even when oral swabs were negative, which indicated to them:

that patients may harbor the virus in the intestine at the early or late stage of disease, and that a blood test for antibodies against the virus should be considered to better understand patterns of infection.

The article explains that the novel coronavirus targets both the lungs and intestines because the virus apparently binds to a type of protein receptor found in both organs.

In a related article, Nature reports that researchers found COVID-19 in rectal swabs of pediatric patients "none of whom required respiratory support or intensive care and all of whom lacked signs of pneumonia." The article also described two other studies that showed similar findings suggesting that, per one expert, "'[a]symptomatic children and adults may be shedding infectious virus and they could transmit it. This is another reason to emphasize good personal hygiene…'"

Using Wastewater as COVID-19 Radar

If the SARS-CoV-2 virus can be found in human stool, then naturally it may exist in municipal wastewater. DW reports that researchers pursued this line of thought and were successful in identifying the novel coronavirus in the wastewater of a city in the Netherlands. In fact, they reportedly identified SARS-CoV-2 ahead of the first confirmed COVID-19 cases in that city, Amersfoort; specifically, they found "that the virus was present in the sewage on March 5, weeks before any cases were reported in the city."

According to the article "[s]ewage surveillance has been previously used to detect the presence of poliovirus and drug prevalence in populations. The [KWR Water Research Institute] is confident their research could be beneficial in tracking the spread of COVID-19."

A related article in Gov Tech, reports that a U.S. startup that has previously surveyed wastewater for opioids is now offering municipalities free analysis of their wastewater to help identify COVID-19 in the local population. According to the article, the startup hopes "testing could also help track the effectiveness of interventions and offer early warnings if the virus re-emerges, if it proves to have a seasonal cycle." The startup also reportedly hopes to provide more to data to help improve epidemiological models.