Covid-19 could linger in the environment

PESHAWAR:

Facing a threat as mysterious and arcane as the novel coronavirus means that researchers are constantly trying understand the obscure contagion and present latest information as it is revealed. Given the rigorous worldwide research, several theories and predictions pertaining Covid-19 have been released in the last few months, only to be replaced and updated by new findings. In March 2020, when the World Health Organisation (WHO) declared Covid-19 as a pandemic, the primary routes of the disease’s viral transmission were considered to be through respiratory droplets and close person-to-person contact. But then, later research also suggested an increasing possibility of fecal to oral transmission, which added to present understanding. However, latest studies carried out by Pakistan’s National Institute of Health (NIH), warns that the virus could affix itself to the environment and open flood gates for a new form of transmission. Supported by the WHO, the research states that despite people not showing Covid-19 symptoms or testing positive in certain areas, the contagion could still be found in sewage and wastewaters and take the region by surprise when its least prepared. “Henceforward, a deep analysis of environmental samples will be an indicator for monitoring the virus and also serve as forewarning for the disease,” it indicated. A copy of the research available with The Express Tribune, reads that the Covid-19 pandemic, caused by SARs-CoV-2, was earlier considered to be transmitted from person-to-person via respiratory droplets and fecal-oral transmission. In order to determine this, the country’s existing polio environment surveillance network was used to investigate presence of SARs-CoV-2 using three commercially available kits and E-Gene detection published assay for surety and confirmation of positive. It further stated that a total of 78 wastewater samples were collected from 38 districts [each sampling site represent 100,000 – 300,000 population] across the country. Out of which 74 wastewater samples were collected from existing polio environment surveillance sites, three from drains of Covid-19 infected areas and one from a Covid-19 quarantine centre drainage. Upon testing all of the samples for presence of SARs-CoV-2, the research reveals, an alarming 21 wastewater samples from 13 districts tested positive. “SARs-CoV-2 RNA positive samples from areas with Covid-19 patients and quarantine center drainage systems strengthen the findings and the use of wastewater surveillance in the future,” the research expounded.

The study findings indicate that SARs-CoV-2 detection through wastewater surveillance has an epidemiological potential. This could be used as an early warning system to monitor viral tracking and circulation in cities with lower Covid-19 disease burden or heavily populated areas where door-to-door tracing may not be possible. “Attention is needed on virus concentration and detection assay to increase sensitivity. Development of highly sensitive assay will be an indicator for virus monitoring and to provide early warning signs,” the study concluded.

Published in The Express Tribune, July 14^th, 2020.