COVID-19 environmental surveillance using sewage water conducted from June to December 31 showed that 96.5%, or 28 out of 29 samples taken from international entry points had the presence of the Omicron variant of the SARS-CoV-2 virus.

Health director-general Dr Noor Hisham Abdullah said the results came from tests at the National Public Health Laboratory with one more sample still being tested.

In the same period, the lab received 301 samples from 15 sentinel locations representing each state in the country.

“A total of 288 samples (95.7%) had the presence of SARSCoV-2 and positive for Omicron. Three had no presence while 10 are still being tested,” he said in a statement today.

He said Malaysia’s Covid-19 environmental surveillance is aimed at being the supplementary surveillance in line with the country’s transition to the endemic phase.

He said detecting the presence of the SARS-CoV-2 in sewage water samples provided early warning by allowing them to get an idea on the virus density trend, identify the variants in the community and monitor the intervention controls’ effectiveness in general.

“For sentinel locations in each state, sewage samples are taken from selected sewage treatment plants by the respective district health office,” he said.

“About two or three samples are taken from each location monthly depending on the need. The samples are then sent to the lab for tests.

“For samples from entry points, risk assessment is continually conducted to identify countries with risk.

“Based on the assessment, all flights from the country are then further studied by the Kuala Lumpur International Airport (KLIA) health office.”

He said in general, all the sewage water is brought out of the airport using lavatory trucks to the aircraft waste disposal facilities (AWDF), which is coordinated by airport ground handlers.

After a targeted flight is identified, the sampling is conducted by the health office at KLIA with the assistance of airport authorities before the sewage water is handed over to AWDF.

Noor Hisham said sewage sampling from aircraft is carried out twice weekly, adding that one litre is taken from selected aircraft.

He said in view of the current situation, the sampling involves aircraft from China.

He said this will enable the Health Ministry to monitor the entry of SARS-CoV-2 variants from entry points as a control measure to face the current situation. – Bernama, January 2, 2023.