SENIOR citizens without health conditions should not take a second booster shot without first consulting a doctor, medical experts said.

They told The Malaysian Insight that the current Covid-19 protocols such as masking, physical distancing and regular hand-washing rare good enough to keep people safe.

There is also a lack of conclusive data on the effectiveness of a fourth shot, they added.

Former deputy health minister Dr Lee Boon Chye said the Israel experience showed that the efficacy of a fourth dose waned after after six to eight weeks.

High-risk groups such as the elderly with co-morbidities and immunocompromised in Malaysia now have the option of getting a fourth dose.

Lee asked: “What is the basis of this recommendation?

“When the vaccine wanes after a few weeks, are they then going to administer a fifth dose two months later?”

Lee said the decision to administer a fourth dose must be based on data and take into account the vaccine side effects.

“Disease risk and post-vaccination side effects have to be balanced. We need data to prove that.”

Existing vaccines may also not be ideal as a second booster shot, Lee added.

“No matter which brand of vaccine you use now, it may not be ideal to deal with the new strains.”

The Health Ministry has made a second booster of a different vaccine brand available to recipients of the Sinovac and Sinopharm primary jabs.

Only for high-risk groups

Virologist Dr Chee Hui Yee said the World Health Organization had only recommended a fourth shot for people who were immunocompromised.

“If you are above 60, have chronic illnesses or are prone to coughs and colds and your respiratory functions are not good, then you can consider getting a fourth shot.

“For senior citizens who are healthy, if they want to get the second booster shot they should first consult a doctor.

“There are concerns that there might be discomfort post-vaccination which will only be detected six to nine months later.”

On whether a fourth shot will be effective against Omicron XE, a mutation of the Omicron BA.1 and BA.2 strains, Chee said there is no data to support this.

Dr Moy Foong Ying from Universiti Malaya’s Social and Preventive Medicine Department agreed that healthy senior citizens should refrain from taking a fourth shot.

“I personally think that it is not necessary for the time being. We should focus on epidemic prevention like wearing masks, washing hands and maintaining physical distance.”

However, senior citizens who have high blood pressure or diabetes can consider getting the fourth dose, she said.

Moy said more attention should also be given to senior citizens who have not received their first booster shot.

“The fourth shot is only 50% effective; if is only if you are very weak that a fourth shot should be considered.

“But if you don’t get three shots of the vaccine you will get severe symptoms if you catch Omicron. Therefore, the government should encourage people to get the third shot first.”

As of April 18, 67.9% of the adult population have received three shots. – April 20, 2022.