KUALA LUMPUR, August 4 — Vaccine breakthrough infections in Malaysia nearly tripled in the past week to some 21,000 total cases, or 15.6 per cent of 132,748 Covid-19 cases reported between July 26 and August 2.
Breakthrough infections in Category Two of disease accounted for 11.1 per cent of the total 132,748 coronavirus cases in that period, followed by Category One (4 per cent), and Category Three (0.35 per cent), while severe cases among the vaccinated in Categories Four and Five comprised 0.1 per cent of total infections.
Official data showed that breakthrough infection rates among vaccinated people — either partially or fully inoculated — more than doubled from 8.5 per cent to 22.4 per cent of daily new coronavirus cases within the span of eight days.
However, 99.3 per cent of 20,684 total breakthrough infections reported from July 26 to August 2 were mild — defined as Categories One to Three of Covid-19 disease — while 97 per cent, or 20,074 cases, were in Categories One and Two. Category Three cases have pneumonia but do not need supplemental oxygen, while Category One and Two are asymptomatic and mild respectively.
Category Four and Five cases — severe cases requiring oxygen or ventilator support — accounted for 0.73 per cent, or 150 cases of the 20,684 breakthrough infections reported from July 26 to August 2.
Dr Christopher Lee, the former national advisor for infectious diseases in the Ministry of Health (MOH), said the data is expected as breakthrough infections among people who have been vaccinated tend to be mild.
“This is the exact objective of the Covid-19 vaccines i.e. to reduce infection risk (which is never 100 per cent), and if infected, to reduce risk of severe disease and death,” he told CodeBlue yesterday when contacted.
However, Dr Lee noted that the data does not specify whether the patients are fully vaccinated or partially vaccinated. Health director-general Dr Noor Hisham Abdullah did not immediately respond to CodeBlue’s request for clarification on MOH’s use of the term “vaccination history”, which refers to breakthrough infection cases. CodeBlue rounded up figures on cases with “vaccination history”, as MOH’s published data only shows percentages.
Vaccine Minister Khairy Jamaluddin said on Monday that the success of the National Covid-19 Immunisation Programme (PICK) will depend on the country’s Covid-19 mortality and hospital admission rates amid reports of breakthrough infections.
Crucial to this is granular data on the classification of people with vaccination history — whether they were fully or partially vaccinated. “I think that will give us better, more granular data on how to interpret the effectiveness of the vaccination programme, especially against the Delta variant,” Khairy said at the Covid-19 Immunisation Task Force (CITF) weekly briefing.
The proportion of vaccine breakthrough infections against daily Covid-19 cases saw a significant jump between July 26 and August 2 — from 8.5 per cent or 1,232 breakthrough infections of 14,516 daily cases on July 26 to 22.4 per cent or 3,525 breakthrough infections out of 15,764 daily cases on August 2.
While the number of breakthrough infections has been rising, Dr Lee said data confirmed that “the large majority of our current cases are among the unvaccinated.”
This is likely attributed to the highly infectious Delta variant — said to be as contagious as chickenpox — with studies showing that vaccinated individuals infected with Delta may be able to transmit the virus as easily as those who are unvaccinated.
According to an internal document by the United States’ Centers for Disease Control and Prevention (CDC), as reported by The Washington Post, while coronavirus vaccines prevent more than 90 per cent of severe disease, they may be less effective at preventing infection or transmission, thus more breakthrough infections and higher community spread may occur.
The CDC document, however, stressed that vaccines reduce the risk of severe disease or death by 10-fold or higher, besides a three-fold reduction in risk of infection.
The federal American agency now recommends wearing a face mask in potential public indoor settings that can spark substantial or high transmission in order to reduce the risk of coronavirus transmission by fully vaccinated people.
Malaysia’s predominantly mild breakthrough infections, albeit inexplicit, seem to fall in line with the latest data from the CDC, where over 99.99 per cent of fully vaccinated individuals in the US have avoided hospitalisation or deaths, despite still being at risk of getting infected with Covid-19.
The data continues to underline the effectiveness of Covid-19 vaccines in preventing serious illness and death from the coronavirus and remains the primary solution for most countries, including Malaysia, to slow the pandemic down.