Detection of the coronavirus in wastewater treatment plants (WWTP) has generated some concern about whether these plants could be a focus for the transmission of covid-19, but according to a study carried out in the province of Granada the risk seems minimal.
Researchers from the Faculty of Pharmacy of the University of Granada (UGR) have carried out a epidemiological analysis, based on rapid covid-19 antibody tests (IgG / IgM) carried out on 134 workers from 59 wastewater treatment plants in the Andalusian province.
The results, published in the International Journal of Water Resources Development, show in this group a seroprevalence (prevalence in blood) of 8.95% in IgG for SARS-CoV-2, a result similar to the incidence rate found for the general population of the province (9.6%).
Both the workers of the wastewater treatment plants and the nearby populations do not have an added risk of covid-19, as they do not register an incidence in antibodies (neither IgG, nor IgM) higher than that of the rest of the population
“This indicates that both these workers and the populations that are near these WWTPs do not have an added risk, as they do not register an incidence of antibodies (neither IgG, nor IgM) higher than those observed in the rest of the population. ”, Explains the main author of this work, professor Maximino Manzanera Ruiz, of the Department of Microbiology of the UGR.
During the treatment of the wastewater, the nucleic acids of SARS-CoV-2 had been detected, which together with the aerosols that are generated, represented, in theory, a risk for the workers of the treatment plants, but these findings indicate that current security measures are sufficient for your protection against covid-19.
The results also suggest that there is no relevant transmission of the coronavirus through wastewater, minimizing the feco-oral transmission of the disease (process by which a disease is transmitted through the feces of an infected person).
Useful information for vaccination
“With these results we can conclude that the risk of infection by the fecal-oral route it is almost nil, In addition, these types of studies make it possible to prioritize which professional sectors should be vaccinated before, because they have a greater risk of contagion, ”says Manzanera.
With these results we can conclude that the risk of infection through the fecal-oral route is almost nil.
Maximino Manzanera Ruiz (UGR)
“On the other hand,” he adds, “our research allows us to monitor the pandemic through wastewater without the need to use high biological security facilities (such as 3 or 4 biohazard laboratories), which allows us to work in a larger number of laboratories for a better follow-up of the incidence ”. In addition, the study points out that the virus detected in the wastewater is inactive, perhaps due to its association with other particles present.
The authors, together with professors from the Higher Technical School of Roads of the UGR and the company Gis4Tech, are currently designing a more effective method of searching for infected persons through the water sanitation network.
Rights: Creative Commons.