PETALING JAYA: With Malaysians apprehensive about taking the heterologous booster shot (mix-and-match approach), public health experts have assured them that no known health issues have risen from such a practice based on studies that have been conducted, noting that the delivery is safe and effective.
Universiti Malaya Department of Social and Preventive Medicine Faculty of Medicine’s Prof Dr Moy Foong Ming said if individuals have no known severe side effects from the Pfizer vaccine, it is safe to get Pfizer as a booster.
“So far, there have been no reported health issues arising from the mixing – from countries such as Indonesia and Chile – using this regime,” she said.
Dr Moy cited a study by the Chile Health Ministry, pointing out that the vaccine effectiveness with Sinovac as the primary vaccine and Pfizer as the booster had increased from 54% to 95% compared to using Sinovac as the booster, in which the vaccine effectiveness increased only to 74%.
As such, to have greater protection against the Delta variant and other variants that might appear in the future, she said a booster shot was necessary, adding that it was better with a heterologous method.
Dr Moy said current vaccines worked well and could prevent severe disease, hospitalisation and deaths, though the double dose vaccines would wane over time.
“A booster dose will stimulate neutralising antibodies, which are the specific antibodies that stop the virus and protect us from getting Covid-19.
“It is important to have the booster dose, but it is even more important to have the first and second doses. Those who have not been vaccinated for two doses should do so quickly,” she added.
Booster doses began nationwide on Oct 13 for eligible individuals.
But the Health Ministry noted that around 40% of recipients slated for their vaccine booster appointment dates under the National Covid-19 Immunisation Programme did not show up.Universiti Putra Malaysia medical epidemiologist Assoc Prof Dr Malina Osman concurred that current studies had shown that administering heterologous vaccines were “safe and effective”.
“Current data shows its effectiveness and safety. There is no data on long-term complications as we are still in the pandemic situation.
“I recommend that all those who are given appointments for the booster dose come forward and be vaccinated on the given date.
“We are now racing against time, so we need to cover the vaccination as soon as possible to prevent further possible transmissions due to waning antibodies,” she said.
Dr Malina added that booster doses were needed to allow the body to produce more antibodies against the infection.
Universiti Putra Malaysia’s consultant clinical microbiologist Prof Dr Zamberi Sekawi said the mixing of vaccines was proven to stimulate a person’s antibodies.
“Maintaining high antibodies is very important for those who are at high risk of getting Covid-19.
“Studies have also shown that if you have higher levels of antibodies, you are well protected against the virus,” he said.
Dr Zamberi, who is also Malaysian Society of Infectious Diseases and Chemotherapy president, urged the public to take this chance to boost their antibodies as cases were rising.
“We don’t know if our antibodies have waned to very low levels, thus exposing ourselves to Covid-19,” he said.
The Health Ministry had in the past assured the public of the efficacy of a heterologous booster shot.
Initially, Pfizer was the only vaccine approved as a booster shot in the country.
Yesterday, the Health Ministry said the Drug Control Authority had given conditional approval for the Sinovac and AstraZeneca vaccines as booster shots in Malaysia.
On Twitter, Health Minister Khairy Jamaluddin reiterated that the Pfizer booster was the best choice to increase an individual’s level of protection.
With an infectivity rate of 1.04 on Tuesday, Khairy in another tweet also urged the public to practise the Covid-19 SOP.
He added that the ministry had finalised a Heightened Alert System that would kick in when indicators breached certain thresholds.