ABSTRACT
The ongoing COVID-19 pandemic is caused by SARs-CoV-2. The virus is transmitted from person to person through droplet infections i.e. when infected person is in close contact with another person. In January 2020, first report of detection of SARS-CoV-2 in faeces, has made it clear that human wastewater might contain this virus. This may illustrate the probability of environmentally facilitated transmission, mainly the sewage, however, environmental conditions that could facilitate faecal oral transmission is not yet clear. We used existing Pakistan polio environment surveillance network to investigate presence of SARs-CoV-2 using three commercially available kits and E-Gene detection published assay for surety and confirmatory of positivity. A Two-phase separation method is used for sample clarification and concentration. An additional high-speed centrifugation (14000Xg for 30 min) step was introduced, prior RNA extraction, to increase viral RNA yield resulting a decrease in Cq value. A total of 78 wastewater samples collected from 38 districts across Pakistan, 74 wastewater samples from existing polio environment surveillance sites, 3 from drains of COVID-19 infected areas and 1 from COVID 19 quarantine center drainage, were tested for presence of SARs-CoV-2. 21 wastewater samples (27%) from 13 districts turned to be positive on RT-qPCR. SARs-COV-2 RNA positive samples from areas with COVID 19 patients and quarantine center strengthen the findings and use of wastewater surveillance in future. Furthermore, sequence data of partial ORF 1a generated from COVID 19 patient quarantine center drainage sample also reinforce our findings that SARs-CoV-2 can be detected in wastewater. This study finding indicates that SARs-CoV-2 detection through wastewater surveillance has an epidemiologic potential that can be used as supplementary system to monitor viral tracking and circulation in cities with lower COVID-19 testing capacity or heavily populated areas where door-to-door tracing may not be possible. However, attention is needed on virus concentration and detection assay to increase the sensitivity. Development of highly sensitive assay will be an indicator for virus monitoring and to provide early warning signs.
Subject(s)
Environmental Monitoring , RNA, Viral/analysis , SARS-CoV-2/genetics , Wastewater/virology , COVID-19/pathology , COVID-19/transmission , COVID-19/virology , Humans , Pakistan , Polyproteins/genetics , Quarantine , Real-Time Polymerase Chain Reaction , SARS-CoV-2/isolation & purification , Viral Proteins/geneticsABSTRACT
Pandemic of novel Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) infections in China is now become global public health crisis. At present 87.64% of the world is infected by this deadly illness. The risk from this epidemic depends on the nature of the virus, including how well it transmits from person to person, and the complications resulting from this current illness. The novel coronavirus has killed thousands of people in China and other countries as well; its rate of mortality is increasing day by day. There is an urgent need to control the virus by developing vaccine or any other antiviral drugs to save the world from this deadly viral infection.
Subject(s)
COVID-19/epidemiology , COVID-19/transmission , Global Health/statistics & numerical data , Public Health , SARS-CoV-2/pathogenicity , Antiviral Agents/therapeutic use , COVID-19/mortality , China/epidemiology , Developing Countries , HumansABSTRACT
The sudden outbreak of the novel Coronavirus infectious disease (COVID-19) resulted in significant challenges to global health systems. One of the primary challenges is rapid, reliable, and accurate detection of the severe acute respiratory syndrome coronavirus 2 (SARS-COV-2) virus among the suspected COVID-19-infected individuals. At present, quantitative real-time PCR (qRT-PCR) is a widely used diagnostic method. However, it requires expensive instruments and expertise in the interpretation of results. These constraints reflect the significant need for the development of alternative diagnostic options. This study will validate the use and efficiency of the reverse transcriptase loop-mediated isothermal amplification (RT-LAMP) assay as a potential alternative for the detection of COVID-19. For this purpose, a cohort of 297 suspected COVID-19 patients was tested using both the RT-LAMP assay and the conventional RT-PCR method. For the RT-LAMP assay, three genes (orf-1ab, N, and S) were identified as the target sites for the detection of COVID-19. Based on a comparative assessment, 117 out of 124 positive COVID-19 cases were observed using the RT-LAMP technique with an overall 91.45% sensitivity. Interestingly, where a consensus on 163 individuals free of SARS-Cov-2 was observed, RT-LAMP specificity was 90%. Based on these findings, the robustness of the technique, and the reduced dependency on expensive instrumentation, RT-LAMP-based COVID-19 detection is strongly recommended as a potential alternative assay.