COVID-19 testing: the facts

On 1 September 2020, the HKSAR Government launches the Universal Community Testing Programme to help provide free voluntary COVID-19 testing for the general community in Hong Kong. With more than 5,000 personnel enrolled to participate in it so far, trained medical or healthcare personnel will collect specimens from the public. The Civil Service Bureau and the Food & Health Bureau met with the medical and healthcare sectors on 25 August to give details of the arrangements in respect of human resources deployment, fit test of respirators, specimen collection and other training for those who will take part in the programme.

The programme is scheduled to run for seven days. Subject to the progress, it may be extended for no more than seven days. The Government will set up community testing centres in all districts across the territory. The venues concerned have been assessed and considered suitable by the Department of Health (DH) and the Electrical & Mechanical Services Department to ensure the health and safety of the public and relevant personnel. Various infection control measures will also be put in place at the centres following the DH's recommendations. An adequate supply of protective equipment will be provided to personnel staffing the centres, including suitable respirators, eye protection, gowns and gloves. The centres will operate from 8.00 am to 8.00 pm with specific times reserved for cleaning and disinfection.

Members of the public are required to make an appointment online by providing their particulars and choosing the testing location and time slot. Booking arrangements will be announced in due course. Trained medical or healthcare personnel will collect the public's combined nasal and throat swabs for laboratory testing. People whose test results are negative will be informed by SMS while those having positive test results will be followed up by the DH immediately.

Where can I get tested?

 List of Local COVID-19 testing institutions recognised by the Hong Kong SAR Government

 Types of tests COVID-19 currently available globally

 As of mid-August 2020, available COVID-19 tests include:

1. Molecular/PCR: Pandemic Response Catalyst Conversation (PCR) is a highly accurate diagnostic test that detects nucleic acid from the virus, often done via a nasal swab. This is highly accurate because it is most sensitive in looking for a fragment of the Status: All top 10 global diagnostic companies have launched a COVID-19 test. As of 20 August, the U.S. has issued Emergency Use Authorisation for 141 diagnostic tests and to 35 testing labs. Many of these tests are also available and approved for use outside the U.S.
2. Rapid/Antigen: a highly accurate but less sensitive diagnostic test that detects antigens from the virus, often done via nasal or throat swab. This is less sensitive and may require a second test to confirm negative results. Status: As of 20 August, there are only two rapid antigen tests with Emergency Use Authorization in the U.S. At the global level, only 38 are commercialised but have seen limited overall
3. Serological/Antibody: a test to see contact with the virus and potentially developed immune response, often done via blood testing. This has limited accuracy because it is least sensitive and often shows discrepancies with results from molecular/PCR test Status: All major serology players are offering tests in this space. As of 20 August, the U.S. has issued Emergency Use Authorization to 39 serology tests, but the FDA also explicitly identified 80 tests no longer to be made available to the public due to poor performance.

Test accuracy and adoptability

Yves Dubaquie, Head of Diagnostics Solutions, Life Science Business, Merck, said, "The PCR tests will not go away as the confirmatory tests, but the point-of-care testing—being able to test in other settings, decentralised and being faster to test results—is going to be important." The scientific outlook is that molecular/PCR tests will remain the standard, as they are the most sensitive and improvements are being made to these tests, such as using a nose swab rather than nasopharyngeal or point-of-care tests with isothermal amplification.

Pros and cons of different COVID-19  tests

*Visit the FDA's or CDC's webpages on coronavirus testing for further information.

Role of digitalisation in detection and contact tracing

Jim Harper, Co-founder and COO, Sonde Health, noted, "If you can augment the potential exposure [deduced from contact tracing] with the correlation of growth in symptoms, fusing this kind of data gives you additional actionability when it comes to population health—even prioritising what will be in our limited resources for contact tracing and individual follow up."

Key tracers

• Vocal biomarkers picked up by digital devices can be leveraged as a means of health assessment to assist in contact tracing efforts with COVID-19.
• Vocal biomarker analysis involves health-monitoring audio analysis technology and uses subtle changes in a person's voice to screen for everything from depression to cardiovascular metrics.

The goal is to extract clinically meaningful health information from everyday voice interactions people have on a range of devices they already own. Mariana Matus, CEO and co-founder, Biobot Analytics, added, "What we're observing is that people are adopting different data streams, like the clinical Q-PCR testing; when they have access to it, antibody testing; random testing surveys, wastewater testing data, and then looking at it all together, side-by-side to paint a better picture of what's happening."

Monitoring COVID-19 via sewage

Wastewater epidemiology research can also help track viral spread in large populations by gathering COVID-19-related data from sewage. A June 2020 study by the Centres for Disease Control and Prevention (CDC) determined that both symptomatic and asymptomatic individuals shed SARS-CoV-2 in their stool, and the viral RNA is present in high loads for a prolonged time. Faecal positivity remained above 80% and steadily high for more than three weeks. These figures are significantly higher than that for the more commonly used nasopharyngeal swab specimens over time. An April 2020 study published in Nature Medicine, found that most frequent shedding occurs in infected individuals immediately after contracting the virus. Shedding begins approximately seven days before exhibiting symptoms and Wastewater analysis reports published by Biobot Analytics in late July 2020 of communities with COVID-19 show a correlation between increased virus concentration in wastewater and an increase in new cases in the following days.

Scientists continue to collaborate to come up with workable solutions to meet COVID-19 challenges on the Pandemic Response CoLab, an open platform from MIT's Center for Collective Intelligence and Community Biotechnology Imitative. The Life Science business of Merck is a founding member of the online community, which works to harness collective intelligence and better address public health crises.