Shedding light on face masks and tests
I WOULD like to clear the confusion and anxiety related to two key social measures — the wearing of quality face masks and Covid-19 testing — to control the spread of Covid-19. This is important so that measures are effective and get the cooperation and support of the public.
Firstly, I refer to the report, “Lowquality face mask a risk to public health”. As someone who advocated the wearing of face masks in public places at the start of the pandemic, I call upon the authorities to implement a minimum quality standard of face masks with correct labelling.
They should come down hard on cases of false labelling, which seems to be prevalent in the unregulated market of face masks for public use now. Most of the three-ply disposable medical face masks, for public use, come from China.
Some months ago, it was reported that there had been many complaints by European countries on the quality of face masks from China, prompting Beijing to issue a “whitelist” of 2,566 manufacturers in China of disposable three-ply face masks meeting the minimum standards of quality set up by the National Medical Products Administration (NMPA), formerly the China Food & Drug Administration.
Based on the feedback, now only a few manufacturers on the NMPA whitelist supply three-ply face masks to Malaysia. Some 90 per cent of the face masks in the market here are of questionable quality and may not be effective in filtering out harmful particles, bacteria and viruses, thereby defeating the purpose of wearing a face mask.
The two common standards of three-ply medical face masks exported fromChina in the approved “whitelist” are the YY 0469 and YY/T 0969. The factory price of the masks is less than RM0.30 each, so it is way below the ceiling price of RM1.
Many unscrupulous traders are profiteering from the sale of face masks at the expense of public health.
So the authorities should allow only the YY 0469 and YY/T 0969 types to be sold to the public and go after those who fraudulently label masks.
The second issue is on Covid-19 testing. There are two types of tests — diagnostic and antibody tests. The common diagnostic test carried out to detect molecular or genetic material of the virus is the real time RT-PCR (reverse transcription polymerase chain reaction) or PCR Test.
It uses a nasal or throat swab, and is reliable and accurate if done by trained personnel, but the results may take at least a day or more. Taking a nasal or throat swab can be uncomfortable and even painful. Therefore, to encourage more people to do testing, the government should consider a new type of PCR test that uses saliva. This test was developed overseas and is available.
A quicker and cheaper diagnostic test to detect fragments of the spike protein of the virus, but which is slightly less accurate, is the Antigen
Test (AT), often with a rapid test kit.
The results can be known in 30 minutes and such tests are popularly used at airports and Immigration centres, where quick results are essential.
It also uses a nasal or throat swab. The United States Food and Drug Adminstration also approved in May a new AT using saliva. It was reported recently that a team of Malaysian scientists has developed a new antigen rapid test kit using saliva.
Antibody tests, not commonly used in Malaysia, are blood tests for determining the presence of antibodies (to the Covid virus), which
would indicate if the subject has been infected. However, it may not tell us when the subject was infected and whether he or she is still infected.
It can also give false results in cases where the antibodies of the subject are only present in the body a week or later after the infection. But this test is useful to know the history of Covid infection of a subject, for epidemiological surveys, including studies on the immunity of a community.