PETALING JAYA: The self-test kits (Rapid Antigen test) that use saliva for Covid-19 screening will ramp up the testing rate in the country but the results must be followed up with a confirmatory RT-PCR test, say health experts.
Universiti Malaya Department of Social and Preventive Medicine Faculty of Medicine’s Prof Dr Moy Foong Ming said these self-testing kits would enable more people to be tested at a faster rate and would take the pressure off diagnostic laboratories.
For individuals, Dr Moy said these testing kits would also reduce the need for people to travel to a healthcare facility to conduct the test and at the same time avoid transmitting the virus to others.
However, Dr Moy noted that the public still must go for a confirmatory reverse transcription polymerase chain reaction (RT-PCR) test as these self-test kits were not as accurate as the gold standard.
“With the home test kits, the government must set new rules that all positive cases must report to the health authorities and proceed with RT-PCR tests,” she said when contacted yesterday.
The RT-PCR test is considered the gold standard in diagnosing Covid-19 and is able to detect minute quantities of Covid-19 virus’ ribonucleic acid (RNA) in the nasal or throat swab sample taken from a person.
“The self-test kits can have false positives or false negatives as these tests are not as accurate as the RT-PCR.
“The test results may also be influenced by the way an individual performs the test. They must read and follow the manufacturer’s instructions in order for the results to be reliable and accurate.
“The home Covid-19 tests may provide accurate positive results in symptomatic individuals while negative test results in symptomatic individuals should be repeated with the RT-PCR test because these tests are usually less accurate.
“When an asymptomatic individual tests positive on a home test kit, the possibility of a false-positive should be considered and the results should be confirmed using the RT-PCR,” she said.
Health director-general Tan Sri Dr Noor Hisham Abdullah had said that studies conducted by the Medical Research Institute found that two self-test devices (Rapid Antigen test) that use saliva for Covid-19 screening have sensitivity levels of above 90%.
Dr Noor Hisham noted that the Medical Device Authority is detailing the usage guidelines, adding that it will be completed by next week.
Universiti Putra Malaysia medical epidemiologist Assoc Prof Dr Malina Osman concurred that these self test-kits would enable more people to be tested, adding that allowing testing to be done at home would reduce logistical issues and charges.
Dr Malina noted that any screening tests too should have the same sensitivity rates as the gold standard.
“If the sensitivity and specificity values are more than 90% for any screening test, then it should be considered as a good and reliable screening test,” she said.
Malaysian Public Health Physicians Association president Datuk Dr Zainal Ariffin Omar believed that these self-testing kits would be easier to handle as patients could do it themselves in their own home.
“The test should speed up our testing capabilities. Also, with a sensitivity rate of more than 90% it is reliable. But, do note that this is only a rapid antigen test not a RT-PCR test so it is good just for screening purposes,” he said.
