Detection of coronavirus in environmental surveillance and risk monitoring for pandemic control.

The novel human infectious coronaviruses (CoVs) responsible for severe respiratory syndromes have raised concerns owing to the global public health emergencies they have caused repeatedly over the past two decades. However, the ongoing coronavirus disease 2019 (COVID-19) pandemic induced by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has received unprecedented attention internationally. Monitoring pathogenic CoVs in environmental compartments has been proposed as a promising strategy in preventing the environmental spread and tracing of infectious diseases, but a lack of reliable and efficient detection techniques is still a significant challenge. Moreover, the lack of information regarding the monitoring methodology may pose a barrier to primary researchers. Here, we provide a systematic introduction focused on the detection of CoVs in various environmental matrices, comprehensively involving methods and techniques of sampling, pretreatment, and analysis. Furthermore, the review addresses the challenges and potential improvements in virus detection techniques for environmental surveillance.

Tracking SARS-CoV-2 in Sewage: Evidence of Changes in Virus Variant Predominance during COVID-19 Pandemic.

Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2), responsible for the ongoing coronavirus disease (COVID-19) pandemic, is frequently shed in faeces during infection, and viral RNA has recently been detected in sewage in some countries. We have investigated the presence of SARS-CoV-2 RNA in wastewater samples from South-East England between 14th January and 12th May 2020. A novel nested RT-PCR approach targeting five different regions of the viral genome improved the sensitivity of RT-qPCR assays and generated nucleotide sequences at sites with known sequence polymorphisms among SARS-CoV-2 isolates. We were able to detect co-circulating virus variants, some specifically prevalent in England, and to identify changes in viral RNA sequences with time consistent with the recently reported increasing global dominance of Spike protein G614 pandemic variant. Low levels of viral RNA were detected in a sample from 11th February, 3 days before the first case was reported in the sewage plant catchment area. SARS-CoV-2 RNA concentration increased in March and April, and a sharp reduction was observed in May, showing the effects of lockdown measures. We conclude that viral RNA sequences found in sewage closely resemble those from clinical samples and that environmental surveillance can be used to monitor SARS-CoV-2 transmission, tracing virus variants and detecting virus importations.

Tracking COVID-19 via sewage.

PURPOSE OF REVIEW: We discuss the potential role of the faecal chain in COVID-19 and highlight recent studies using waste water-based epidemiology (WBE) to track severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). RECENT FINDINGS: WBE has been suggested as an adjunct to improve disease surveillance and aid early detection of circulating disease. SARS-CoV-2, the aetiological agent of COVID-19, is an enveloped virus, and as such, typically not associated with the waste water environment, given high susceptibility to degradation in aqueous conditions. A review of the current literature supports the ability to detect of SARS-CoV-2 in waste water and suggests methods to predict community prevalence based on viral quantification. SUMMARY: The summary of current practices shows that while the isolation of SARS-CoV-2 is possible from waste water, issues remain regarding the efficacy of virial concentration and subsequent quantification and alignment with epidemiological data.

Environmental and decontamination issues for human coronaviruses and their potential surrogates.

Pandemic coronavirus disease-2019 (COVID-19) gives ample reason to generally review coronavirus (CoV) containment. For establishing some preliminary views on decontamination and disinfection, surrogate CoVs have commonly been assessed. This review serves to examine the existing science in regard to CoV containment generically and then to translate these findings into timely applications for COVID-19. There is widespread dissemination of CoVs in the immediate patient environment, and CoVs can potentially be spread via respiratory secretions, urine, and stool. Interpretations of the spread however must consider whether studies examine for viral RNA, virus viability by culture, or both. Presymptomatic, asymptomatic, and post-14 day virus excretion from patients may complicate the epidemiology. Whereas droplet spread is accepted, there continues to be controversy over the extent of possible airborne spread and especially now for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). CoVs are stable in body secretions and sewage at reduced temperatures. In addition to temperature, dryness or relative humidity, initial viral burden, concomitant presence of bioburden, and the type of surface can all affect stability. Generalizing, CoVs can be susceptible to radiation, temperature extremes, pH extremes, peroxides, halogens, aldehydes, many solvents, and several alcohols. Whereas detergent surfactants can have some direct activity, these agents are better used as complements to a complex disinfectant solution. Disinfectants with multiple agents and adverse pH are more likely to be best active at higher water temperatures. Real-life assessments should be encouraged with working dilutions. The use of decontamination and disinfection should be balanced with considerations of patient and caregiver safety. Processes should also be balanced with considerations for other potential pathogens that must be targeted. Given some CoV differences and given that surrogate testing provides experimental correlates at best, direct assessments with SARS-CoV, Middle East respiratory syndrome-related coronavirus (MERS-CoV), and SARS-CoV-2 are required.