The National Polio Laboratory (NPL) of the Research Institute for Tropical Medicine (RITM) on December 7, 2022 informed its stakeholders through the 7th Polio Multistakeholders’ Meeting (MSHM) about updates on environmental surveillance (ES) of polioviruses and other pathogens in the Philippines; progress on the establishment of a concentration laboratory in Mindanao; and transition plans of ES in the country.
With the proposed concentration laboratory in Mindanao, NPL shall now be able to expedite detection of viral pathogens and address the challenge of compromised integrity of samples from the said region due to prolonged transport.
Coupled with the physical expansion of ES is NPL’s vision to also establish a genome sequencing laboratory for SARS-CoV-2 testing based on the existing polio ES network. This comes after the realized need to expand coverage of testing of other viral pathogens and aid in early outbreak response to prevent future epidemics and pandemics.
Aside from polioviruses and SARS-CoV-2, wastewater-based epidemiology (WBE) has been proven effective in the detection of other viruses causing infectious such as hepatitis A and monkeypox.
“ES provides valuable supplementary information, particularly in urban populations where surveillance is limited especially in situations where people are no longer going to hospitals for testing, persistent virus circulation is suspected, or frequent virus reintroduction is perceived. We have recognized its importance during the ‘twindemic’ of polio and SARS-CoV-2,” said RITM Director Dr. Celia Carlos in her opening remarks.
From only two (2) regions and three (3) sites covered in 2017, the NPL ES network is now covering all 17 regions in the country and is currently monitoring 54 sites in 48 provinces. By 2023, NPL eyes to bring the numbers up to 81 provinces, 10 major cities, and 69 sites.
Establishment of Mindanao ES laboratory
The establishment of the Mindanao ES concentration laboratory (ESCL) currently follows a phase-based approach which is aimed to be completed by 2024. It shall undergo four (4) phases which include advocacy and consultation, capacity building, pilot implementation, and sustainability, monitoring, and evaluation.
On August 2022, NPL has already completed Phase 1 of the establishment, which entails all preliminary consultations with relevant partners have already been accomplished and that a specific location in Davao has already been selected for the laboratory. As cascaded in the previous MSHM, Davao is an ideal choice for laboratory establishment as its location strategically allows for air, naval, and land transport of samples.
Phase 1 activities included frequent engagements with the Davao Center for Health Development (CHD), and the Davao Regional Epidemiology and Surveillance Unit (RESU) for risk and on-site assessments of the proposed location and area.
As for the second phase of establishment, NPL is expected to complete all capacity building efforts after delivery and set-up of equipment to the Mindanao ESCL. NPL has hired and trained new staff for the laboratory in the person of Ms. Haya Ahlea Yusop who is expected to regularly process 13 samples from Mindanao regions and report results to NPL.
Once fully established, Mindanao ESCL shall perform two-phase concentration of wastewater samples. On the other hand, RITM shall perform virus isolation and molecular testing of concentrates. Pilot implementation of the Mindanao ESCL is targeted to be rolled out by March 2023.
Aside from Mindanao, preparations for the establishment of the Luzon and Visayas ESCLs are also underway. NPL is currently procuring supplies and identifying an available facility for the establishment of the Visayas ESCL. As for the proposed Luzon ESCL, NPL has already reached out to the Manila Waters Company Inc. (MWCI) last November 2022 for their assistance in the necessary preparations.
Diversifying Pathogen Testing
The 7th Polio MSHM also served as an avenue for the in-depth discussion of WBE and ES for COVID-19. NPL Technical Supervisor Dr. Lea Apostol presented her study that reveals that wastewater RNA peaked weeks prior to peak in reported clinical data of COVID-19 infections. Omicron variants were also detected in the samples before these were detected in humans.
Backed by research, ES for SARS-CoV-2 can prove crucial for effective COVID-19 management in the country. Specifically, this will provide information on the level of infection in a geographical scale, and can complement national COVID-19 testing efforts.
“Following the acute phase of the COVID-19 pandemic, we see the importance of sustaining environmental surveillance as a source of information; like other countries, we now realize the importance of monitoring other pathogens as well in the environment,” said Dr. Apostol on behalf of RITM Laboratory Research Division Chief Dr. Amado Tandoc III.
To achieve the goal of SARS-CoV-2 detection through ES, NPL aims to transition its testing algorithm from virus isolation to polymerase chain reaction (PCR), and genome sequencing. Eventually, NPL aims to establish a sequencing laboratory.
“[A]side from the fact that it will provide us with advanced laboratory technologies, this will also improve [turnaround time] in releasing [of] results…For further confirmatory tests (for SARS-CoV-2), it will take up to 35 days before we could release the results. But once we [could] do the sequencing, turnaround time will take 28 days or even less,” elaborated NPL Science Research Specialist II Ma. Anne-Lesley Valencia.
On October 20, 2022, NPL, World Health Organization (WHO), and the Victorian Infectious Diseases Reference Laboratory (VIDRL) in Australia convened through an online meeting to discuss the necessary preliminary activities for the establishment of the sequencing laboratory by 2023.
by Anel Azel Dimaano