CHECKING for sewage water bugs proved to be an effective monitoring tool during the Covid-19 pandemic and could prove to be an efficient addition to Bahrain’s public health arsenal during any future crises, according to a recently released report.
The research study titled ‘Presence of SARS-CoV-2 virus in wastewater in the Kingdom of Bahrain during the Covid-19 pandemic’ was conducted by researchers from a number of ministries including Health, Works, Municipalities Affairs and Agriculture, as well as Eastern Health Cluster, Salmaniya Medical Complex, Mansoura University and Al Malaki Hospital.
The findings of the report have been shared on Authorea and are set to be peer-reviewed for submission to an academic journal.
“Several countries, including Bahrain, used wastewater surveillance for disease activity monitoring,” researchers wrote.
“This study aimed to determine the presence of SARS-CoV-2 in untreated wastewater and to correlate it with the disease spread.”
Wastewater samples collected by public health laboratories between October 2020 and October 2022 were reviewed retrospectively.
These samples had been collected from areas across Bahrain and had been subjected to real-time polymerase chain reaction (PCR) tests. These results were then correlated with the number of Covid-19 cases in the area.
Of a total of 387 wastewater samples, 103 or 26.6 per cent samples tested positive.
In late 2020, of 42 samples collected from drainage systems of 42 residential blocks, four or 9.5pc tested positive. The positive samples came from the areas with Covid-19 isolation and treatment facilities, specifically Bahrain International Hospital, Sitra Isolation Centre, Block 742 in A’ali and Block 901 in Hunnaniyah.
The report noted that while wastewater surveillance was initiated in 2020, it was not conducted regularly until 2022.
Between February and October 2022, 345 specimens of wastewater were tested, and 99 or 28.7pc were positive. These samples were taken from 123 distinct residential blocks.
During 2022, peaks were detected in February (60pc), June (45pc), and July (43pc) which corresponded to spikes in the spread of the disease.
Conversely, the lowest detection rate was in August (11pc) and September (0pc) respectively, corresponding to the low number of Covid-19 cases.
Researchers noted that during the initial phase of the pandemic, testing was largely prompted by symptoms, which could easily lead to asymptomatic transmission, resulting in under-detection of the disease spread.
“The wastewater-based surveillance provided an almost real-time, low-cost method to monitor the level of community transmission of SARS-CoV-2,” they added.
“The level of SARS-CoV-2 can be an indication of the presence of a cluster of cases in certain areas and can help in detecting local outbreaks.
“This can assist public health and hospital officials in planning for the mitigation process as well as gauge hospital bed availability and the required care needed.
“Additionally, wastewater surveillance offers valuable data guiding policymakers and helping to monitor the effectiveness of public health measures implemented.”
The research conducted using data from laboratory samples was ethically approved by the Health Research Committee in the Health Ministry.
naman@gdnmedia.bh
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