Evaluating effectiveness, protection of boosters

Dr Andrew Kiyu Dawie Usop speaks during the virtual talk.

KUCHING: Based on recent observations and development of vaccines and varying results, experts have propounded the possibility that booster doses of the Covid-19 vaccine may be needed to provide effective protection against other variants of the virus.

In saying this, Sarawak Covid-19 Vaccine Advisory Group (Scovag) chairman Prof Datuk Dr Andrew Kiyu Dawie Usop said there are ongoing studies regarding the effectiveness of vaccines against certain variants.

“These variants are from the mutation of the virus. There are various variants and some can be more infectious, some can evade the antibodies in the body, and so on,” he said during Sarawak Development Institute’s (SDI) brown bag virtual talk on ‘Sarawak Covid-19 Vaccination Campaign’ held via Zoom today.

He said some of these Covid-19 variants were the B.1.1.7 variant which was first found in the United Kingdom, B.1.351 (South Africa), and P.1 (Brazil).

He explained that the efficacies of the current vaccines against some of these variants were not the same.

“For instance, for the UK (variant), the vaccines have the same efficacy. However, it is the South African variant which is the main concern and the cause questioning whether you need to have a booster dose to fight against the variant.”

“In the first place, it is important for vaccines that we use to be highly efficacious. This will prevent the emergence of variants,” added Dr Kiyu, who is also a professor of Public Health in the Faculty of Medicine and Health Sciences of Universiti Malaysia Sarawak (Unimas).

He stressed that Covid-19 vaccines had a role in reducing new cases, severe cases, and deaths. He said vaccinating a high proportion of the population, around 70 to 80 percent, could also prevent the formation of epidemics.

Addressing concerns on whether the vaccine would be safe for people with allergies, he said minor allergies such as asthma were not an absolute contraindication.

He said vaccine recipients with allergies could also request to be observed by medical personnel at the vaccination centre for longer than the usual observation period of 15 minutes.

Dr Radziah Mohamad, public health specialist and principal assistant director of the Family Health Development Section of the State Health Department (JKNS), assured that people with allergies or comorbidities would be assessed at the vaccine centre by medical personnel before being vaccinated.

“If they are not fit to be vaccinated at that time, they may defer or they may advise the person to go to the hospital to take the vaccine in a better place in preparation for if anything untoward happens.”

She added that those with health issues such as diabetes, asthma, and hypertension should be vaccinated as they are at risk of complications if they get infected with Covid-19.

Dr Kiyu said people with human immunodeficiency virus (HIV) or acquired immunodeficiency syndrome (AIDS) and cancer should receive the vaccine. This is due to the low immunity and their antibody response that may not be as high.

Dr Radziah said according to official guidelines, the Pfizer-BioNTech vaccine was safe for pregnant and breastfeeding mothers whereby the Sinovac vaccine is not. There is yet safety data available for pregnant women in regards to this matter. 

She also said that the current guidelines stated that those who had already been infected with Covid-19 could be deferred for three to six months.

“We have a limited supply of vaccines and those who have been infected before already have their protection. Thus, it is safe to defer them and we will follow up with their vaccination after three to six months.”