Some reports of adverse events from Pfizer vaccine recorded in Singapore: MOH official

A nurse prepares to vaccinate healthcare workers at Gleneagles hospital, during the coronavirus disease (COVID-19) outbreak, in Singapore January 19, 2021. REUTERS/Edgar Su
A nurse prepares to vaccinate healthcare workers at the Gleneagles Hospital, during the coronavirus disease outbreak in Singapore on 19 January, 2021. (PHOTO: Reuters)

SINGAPORE — Authorities have received some reports of adverse events arising from a number of people who have received the Pfizer-BioNTech COVID-19 vaccine in Singapore, said a top health official on Friday (22 January).

These reports are in the process of being compiled for submission to the COVID-19 vaccination expert panel for review and recommendations, Ministry of Health (MOH) director of medical services Kenneth Mak said during a virtual COVID-19 multi-ministry taskforce press conference.

“As soon as we're able to get those recommendations out and we have organised and categorised these adverse events, we will be then able to publicise and inform you what those adverse events are,” said Associate Professor Mak, who did not provide a figure on the number of such reports.

Prof Mak noted that in countries that have launched vaccination programmes, the majority of adverse events are very mild. These include pain, redness, swelling, and soreness of the muscles after jabs were administered.

“There are some who have reported fatigue, more generalised muscle aches, and fever. Many of these symptoms, in fact, reflect the body's immune system responding to the vaccine dose that has been injected in them, he added.

“And (there) will be some that may have more serious side effects, which include allergic reactions of a variety of different grades of severity.”

In the US, allergic reactions are occurring at a rate of 11.1 per 1 million vaccinations, according to local health officials. By comparison, flu vaccines cause about 1.3 such reactions per million doses administered.

In Singapore, more than 60,000 people have received their first dose of the Pfizer-BioNTech vaccine as of Friday, including those working in healthcare, nursing homes, frontline and essential services, and seniors in nursing homes.

Separately, 39 staff at the National Centre for Infectious Diseases (NCID) have received their second dose of the vaccine. From next Wednesday, some 5,000 to 10,000 senior residents per precinct in Ang Mo Kio and Tanjong Pagar will be able to receive the vaccine under a pilot.

Prof Mak also spoke at length about the process for tracking such adverse events.

“This goes through the institutions which perform the vaccinations, as well as other doctors who may see patients who have had the vaccination, and have had any adverse effects,” he said.

These reports are then sent to the Health Sciences Authority (HSA), which has a pharmacovigilance programme in place to receive and process them. Such reports are reviewed by expert panels within the HSA to determine the severity of the adverse events.

Reports will also be sent to the MOH, where experts would be consulted to determine whether authorities need to tweak the list of precautions to be taken for the vaccination exercise, said Prof Mak.

He also said that authorities are “very close” to reaching a decision for a second vaccine pending the HSA’s approval, but did not specify which company would be chosen.

Currently, only the Pfizer-BioNTech COVID-19 vaccine has been approved by the HSA for pandemic use here. Two doses are required 21 days apart and it would take up to another two weeks after the second dose for those undergoing vaccination to achieve maximum protection against the virus.

The government has signed advanced purchase agreements with Moderna and Sinovac.

“We anticipate that we would have a decision made soon in our evaluation for one of the vaccines. The other vaccine, I understand, we are still clarifying further details with the company that produces the vaccine,” said Prof Mak.

“We are hopeful that if we are able to get all the information necessary for evaluation, then the HSA can complete its review process and give approval for the other vaccines as well.”

At the press conference, Health Minister and taskforce co-chair Gan Kim Yong said one scheduled Pfizer-BioNTech shipment has been delayed, and that there may be other delays to the shipments of vaccines due to Pfizer’s upgrading of its European manufacturing plant.

“We will continue to monitor our supplies closely to meet our target of vaccinating all Singaporeans and long-term residents in Singapore by the end of this year. But we will need to calibrate our roll out in tandem with our supplies,” he added.

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