Researchers assess wastewater sampling for SARS-CoV-2 surveillance

In a recent study published in the PLoS ONE journal, researchers assessed the feasibility of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) surveillance using wastewater sampling.

Study: The feasibility of SARS-CoV-2 surveillance using wastewater and environmental sampling in Indonesia. Image Credit: Vastram/Shutterstock
Study: The feasibility of SARS-CoV-2 surveillance using wastewater and environmental sampling in Indonesia. Image Credit: Vastram/Shutterstock

Coronavirus disease 2019 (COVID-19) patients have been found to shed the virus in their stools without displaying any gastrointestinal symptoms. As a result, SARS-CoV-2 ribonucleic acid (RNA) can be found in environmental wastewater, which comprises human excreta and wastewater from sewage treatment facilities. Wastewater monitoring for public health purposes has been used to check for the presence of drugs of abuse, such as opioids, antimicrobial-resistant enteric bacteria, and the poliovirus in local populations. It has been suggested that regular testing for SARS-CoV-2 in wastewater could help identify current outbreaks or anticipate potential ones.

About the study

In the present study, researchers investigated the feasibility of conducting wastewater-based epidemiology (WBE) surveillance in Indonesia.

The team built the first wastewater-based SARS-CoV-2 epidemiology surveillance program in the Special Region of Yogyakarta province in Indonesia. The province has two different types of wastewater treatment plant (WWTP) systems in operation: (1) a central WWTP run by the provincial government and (2) community WWTPs, which are autonomously run by each local community.

In three of the five districts in the Special Region of Yogyakarta province, routine WBE surveillance and soil testing were started. As these regions have the maximum coverage of the central wastewater system, the team selected six sub-districts from Yogyakarta city and two each from Sleman district and Bantul district. Furthermore, 12 clustered settlements were chosen that used small community WWTPs. The grab sampling technique or passive sampling was used to collect the samples.

Barcodes for each sample were pre-printed on the bottles. The central and community WWTPs, rivers, septic tanks, and several entry sites of a torpedo-style passive sampler were employed to gather samples. The passive samplers were collected 24 hours post-deployment. Zip-lock bags were used to collect soil samples. Before RNA extraction and reverse-transcription quantitative real-time polymerase chain reaction (RT-qPCR) analysis, all processed samples from soil samples, passive samplers, and wastewater samples were kept at -80 °C. The SARS-CoV-2 RT-PCR assay and synthetic SARS-CoV-2 RNA control were used to identify the SARS-CoV-2 RNA.

The recovery efficiency and the actual value of SARS-CoV-2 RNA were also reported. Multiple SARS-CoV-2 RNA controls, such as an MS2 phage control at various known concentrations and negative control, were included in each qPCR run. Additionally, the RT-qPCR assay's limit of detection (LOD) was established.

Results

A total of 544 samples were obtained throughout the 10-week sampling period, and 54% of them tested positive for SARS-CoV-2 RNA. For positive results for the SARS-CoV-2 nucleocapsid (N) and open reading frame (ORF)-1ab genes, the median cycle threshold (Ct) values were 35.1 and 33.9, respectively. Manhole samples had the highest positive rate, whereas soil samples had the lowest.

The samples collected in July 2021 had the highest positivity rate of 77%. By the end of September 2021, the rate had dropped to 25%, reflecting a decreased detection rate correlated with a reduction in the frequency of reported COVID-19 clinical cases in the community. By employing the grab approach, the N gene was found in 74% of sewage samples, 64% of near-source tracking (NST) water samples, 50% of river samples, and 3% of NST soil samples. This result was in line with the ORF1ab gene target; however, more soil samples tested positive for the ORFlab gene than for the N gene.

Overall, the study findings showed that it was possible to track the community burden of infections in Indonesia by implementing a WBE surveillance system for SARS-CoV-2. Additional information about the prevalence and distribution of COVID-19 in the community is revealed by this combination of sampling techniques. Future research is needed to determine whether WBE can detect SARS-CoV-2 outbreaks early in this environment.

Journal reference:
Bhavana Kunkalikar

Written by

Bhavana Kunkalikar

Bhavana Kunkalikar is a medical writer based in Goa, India. Her academic background is in Pharmaceutical sciences and she holds a Bachelor's degree in Pharmacy. Her educational background allowed her to foster an interest in anatomical and physiological sciences. Her college project work based on ‘The manifestations and causes of sickle cell anemia’ formed the stepping stone to a life-long fascination with human pathophysiology.

Citations

Please use one of the following formats to cite this article in your essay, paper or report:

  • APA

    Kunkalikar, Bhavana. (2022, October 18). Researchers assess wastewater sampling for SARS-CoV-2 surveillance. News-Medical. Retrieved on June 17, 2024 from https://www.news-medical.net/news/20221018/Researchers-assess-wastewater-sampling-for-SARS-CoV-2-surveillance.aspx.

  • MLA

    Kunkalikar, Bhavana. "Researchers assess wastewater sampling for SARS-CoV-2 surveillance". News-Medical. 17 June 2024. <https://www.news-medical.net/news/20221018/Researchers-assess-wastewater-sampling-for-SARS-CoV-2-surveillance.aspx>.

  • Chicago

    Kunkalikar, Bhavana. "Researchers assess wastewater sampling for SARS-CoV-2 surveillance". News-Medical. https://www.news-medical.net/news/20221018/Researchers-assess-wastewater-sampling-for-SARS-CoV-2-surveillance.aspx. (accessed June 17, 2024).

  • Harvard

    Kunkalikar, Bhavana. 2022. Researchers assess wastewater sampling for SARS-CoV-2 surveillance. News-Medical, viewed 17 June 2024, https://www.news-medical.net/news/20221018/Researchers-assess-wastewater-sampling-for-SARS-CoV-2-surveillance.aspx.

Comments

The opinions expressed here are the views of the writer and do not necessarily reflect the views and opinions of News Medical.
Post a new comment
Post

While we only use edited and approved content for Azthena answers, it may on occasions provide incorrect responses. Please confirm any data provided with the related suppliers or authors. We do not provide medical advice, if you search for medical information you must always consult a medical professional before acting on any information provided.

Your questions, but not your email details will be shared with OpenAI and retained for 30 days in accordance with their privacy principles.

Please do not ask questions that use sensitive or confidential information.

Read the full Terms & Conditions.

You might also like...
IgG from long COVID patients induces specific symptoms in mice, confirming autoimmunity's role