The Pfizer-BioNTech vaccine is safe and effective for children aged 12 to 15, the Expert Committee on Covid-19 Vaccination said last night in response to an open letter penned by some doctors which was later retracted.
"The Pfizer-BioNTech vaccine is currently the only Covid-19 vaccine anywhere in the world that has been authorised for use in adolescents aged 12 to 15 years," said the committee.
"The safety profile of the vaccine is consistent with the known safety profile in the adult population and the standards set for other registered vaccines used in immunisation against other diseases."
On Thursday night, 12 doctors posted an open letter calling for children to be given traditional Covid-19 vaccines instead of mRNA ones.
Singapore currently uses two vaccines - Pzifer-BioNTech and Moderna. Both use mRNA technology, which gets cells to make a protein piece on its surface that triggers an immune response.
The Health Sciences Authority (HSA) is still studying the Sinovac vaccine, which is made using a traditional method where killed virus is used. The body recog-nises this and mounts an immune response.
Eleven of the 12 doctors later retracted the letter, saying that "some of our thoughts may be misunderstood by some laypersons. We will, henceforth, ponder in a more professional and pri-vate forum".
The open letter was posted on the HardwareZone forum and also appeared in at least one Telegram chat on vaccination. The retraction appeared in some chats and was confirmed by Dr Paul Yang, the author of the letter.
Dr Yang, a general practitioner, told The Straits Times: "The letter was posted prematurely. It is a letter of advice to my church parents' group. The technical issues are unfortunately too complicated, but accurate factually."
The open letter, which was addressed to "all parents deciding to vaccinate or not to vaccinate their child", caused concern among some parents of young children, especially as two of the doctors who signed it had also signed an open letter in February last year urging people to wear masks when going out - about two months before it was made mandatory here.
In its response yesterday, the Expert Committee on Covid-19 Vaccination said it had recommended that the Pfizer vaccine be used among those aged 12 to 15 years following HSA's approval.
"Our assessment remains that the Pfizer-BioNTech vaccine is safe and efficacious for this age group," it said. "There is currently no credible evidence of an inactivated virus vaccine demonstrating a high vaccine efficacy and safety profile among this age group."
The statement said the committee had noted the contents of the open letter and that 11 of the 12 doctors have retracted it.
The committee said the population in Singapore, including adolescents, continue to remain at risk of infection and onward transmission to their close contacts, as seen in recent local cases and outbreaks involving schoolgoing children.
While the international experience is that Covid-19 appears milder among the young, there remains a risk of complications and long-lasting symptoms in children and adolescents.
"The expert committee therefore recommends that with the availability of a safe and efficacious vaccine, all eligible per-sons should receive the vaccine to attain as high a population coverage of Covid-19 vaccination as possible."
Responding to what was in the open letter, the committee said Covid-19 vaccines cannot alter a person's DNA.
The Pfizer-BioNTech vaccine comprises messenger RNA (mRNA) that contains the ins-tructions to enable the vaccine recipient to build a protein component of the Sars-CoV-2 virus, or spike protein.
"The spike protein does not cause infection, but is recognised by the body's immune system as foreign. The body then mounts an immune response and produces antibodies that protects against future infection by the virus," the committee said.
"The vaccine mRNA is broken down by the body rapidly after the spike protein is built. The mRNA is unable to produce more copies of itself and cannot enter the nucleus of the human cells, where human genetic material ("DNA") is stored," it said.
"Since the human genome is made up of DNA, it is not biologically plausible for the vaccine mRNA to be integrated or to interfere with the DNA of the vaccine recipient."
The chairman of the expert committee, Associate Professor Benjamin Ong, said the vaccine was assessed to be safe and effective for the 12 to 15 age group "after careful assessment and deliberation of the available clinical data".
"There is no inactivated Covid-19 vaccine approved for use in children yet," he added.
The committee said that with more than 200 million doses of the Pfizer vaccine used worldwide, there is currently no evidence for rare but serious effects beyond anaphylaxis, which is a severe allergic reaction that can kill unless treated promptly.
The committee and HSA will continue to monitor and review evidence and information that emerge on long-term safety and efficacy, it said.
Some doctors and scientists said they were aghast at what was put out in the open letter.
Professor Ooi Eng Eong of Duke-NUS Medical School, an expert on emerging infectious diseases who has been involved in developing an mRNA vaccine, said their argument is "pseudoscience" and based on "a lot of misunderstanding of molecular biology and immunology".
He said: "The development of mRNA vaccine, although rapid, was based on more than 20 years of painstaking research. This vaccine technology was not assembled in a hurry. Instead, the world was fortunate that this technology matured at a time when it was needed most."
Dr Desmond Wai, a gastroenterologist in private practice, said that "as a doctor, if I have an academic question, I should ask the Ministry of Health or the experts, directly - especially if my viewpoint/interpretation is different from the mainstream".
He added: "Giving an opinion in the public domain causes confusion to the public. I am aware that as a doctor, the public will take my opinion seriously. So, all the more I should be careful when I give opinions in public."
Dr Kenneth Lyen, a paediatrician in private practice, also disagreed with several of the points raised in the letter. He said: "We are all concerned about the safety and efficacy of vaccines. Life is full of risks and balances. It is safer to be vaccinated than to cross a Singapore street. The choice is yours."