tetano
Editor, Senior Moderator
Virus Res
. 2021 Jun 16;198484.
doi: 10.1016/j.virusres.2021.198484. Online ahead of print.
A novel RdRp-based colorimetric RT-LAMP assay for rapid and sensitive detection of SARS-CoV-2 in clinical and sewage samples from Pakistan
Muhammad Farhan Ul Haque[SUP] 1 [/SUP], Syeda Sadia Bukhari[SUP] 1 [/SUP], Rabia Ejaz[SUP] 1 [/SUP], Faheem Uz Zaman[SUP] 2 [/SUP], Kamalalayam Rajan Sreejith[SUP] 3 [/SUP], Naeem Rashid[SUP] 1 [/SUP], Muhammad Umer[SUP] 4 [/SUP], Naveed Shahzad[SUP] 5 [/SUP]
Affiliations
Abstract
Novel corona virus SARS-CoV-2, causing coronavirus disease 2019 (COVID-19), has become a global health challenge particularly for developing countries like Pakistan where overcrowded cities, inadequate sanitation, little health awareness and poor socioeconomic conditions exist. The SARS-CoV-2 has been known to spread primarily through direct contact and respiratory droplets. However, detection of SARS-CoV-2 in stool and sewage, have raised the possibility of fecal-oral mode of transmission. Currently, quantitative reverse-transcriptase PCR (qRT-PCR) is the only method being used for SARS-CoV-2 detection, which requires expensive instrumentation, dedicated laboratory setup, highly skilled staff, and several hours to report results. Considering the high transmissibility and rapid spread, a robust, sensitive, specific and cheaper assay for rapid SARS-CoV-2 detection is highly needed. Herein, we report a novel colorimetric RT-LAMP assay for naked-eye detection of SARS-COV-2 in clinical as well as sewage samples. Our SARS-CoV-2 RdRp-based LAMP assay could successfully detect the virus RNA in 26/28 (93%) of RT-PCR positive COVID-19 clinical samples with 100% specificity (n = 7) within 20 min. We also tested the effect of various additives on the performance of LAMP assay and found that addition of 1 mg/ml bovine serum albumin (BSA) could increase the sensitivity of assay up to 10[SUP]1[/SUP] copies of target sequence. Moreover, we also successfully applied this assay to detect SARS-CoV-2 in sewage waters collected from those areas of Lahore, a city of Punjab province of Pakistan, declared as virus hotspots by local government. Our optimized LAMP assay could provide a sensitive first tier strategy for SARS-CoV-2 screening and can potentially help diagnostic laboratories in better handling of high sample turnout during pandemic situation. By providing rapid naked-eye SARS-CoV-2 detection in sewage samples, this assay may support pandemic readiness and emergency response to any possible virus outbreaks in future.
Keywords: COVID-19; LAMP; RdRp; SARS-CoV-2; sewage water.
. 2021 Jun 16;198484.
doi: 10.1016/j.virusres.2021.198484. Online ahead of print.
A novel RdRp-based colorimetric RT-LAMP assay for rapid and sensitive detection of SARS-CoV-2 in clinical and sewage samples from Pakistan
Muhammad Farhan Ul Haque[SUP] 1 [/SUP], Syeda Sadia Bukhari[SUP] 1 [/SUP], Rabia Ejaz[SUP] 1 [/SUP], Faheem Uz Zaman[SUP] 2 [/SUP], Kamalalayam Rajan Sreejith[SUP] 3 [/SUP], Naeem Rashid[SUP] 1 [/SUP], Muhammad Umer[SUP] 4 [/SUP], Naveed Shahzad[SUP] 5 [/SUP]
Affiliations
- PMID: 34146608
- DOI: 10.1016/j.virusres.2021.198484
Abstract
Novel corona virus SARS-CoV-2, causing coronavirus disease 2019 (COVID-19), has become a global health challenge particularly for developing countries like Pakistan where overcrowded cities, inadequate sanitation, little health awareness and poor socioeconomic conditions exist. The SARS-CoV-2 has been known to spread primarily through direct contact and respiratory droplets. However, detection of SARS-CoV-2 in stool and sewage, have raised the possibility of fecal-oral mode of transmission. Currently, quantitative reverse-transcriptase PCR (qRT-PCR) is the only method being used for SARS-CoV-2 detection, which requires expensive instrumentation, dedicated laboratory setup, highly skilled staff, and several hours to report results. Considering the high transmissibility and rapid spread, a robust, sensitive, specific and cheaper assay for rapid SARS-CoV-2 detection is highly needed. Herein, we report a novel colorimetric RT-LAMP assay for naked-eye detection of SARS-COV-2 in clinical as well as sewage samples. Our SARS-CoV-2 RdRp-based LAMP assay could successfully detect the virus RNA in 26/28 (93%) of RT-PCR positive COVID-19 clinical samples with 100% specificity (n = 7) within 20 min. We also tested the effect of various additives on the performance of LAMP assay and found that addition of 1 mg/ml bovine serum albumin (BSA) could increase the sensitivity of assay up to 10[SUP]1[/SUP] copies of target sequence. Moreover, we also successfully applied this assay to detect SARS-CoV-2 in sewage waters collected from those areas of Lahore, a city of Punjab province of Pakistan, declared as virus hotspots by local government. Our optimized LAMP assay could provide a sensitive first tier strategy for SARS-CoV-2 screening and can potentially help diagnostic laboratories in better handling of high sample turnout during pandemic situation. By providing rapid naked-eye SARS-CoV-2 detection in sewage samples, this assay may support pandemic readiness and emergency response to any possible virus outbreaks in future.
Keywords: COVID-19; LAMP; RdRp; SARS-CoV-2; sewage water.