UALA LUMPUR: Covid-19 booster shots are needed after a certain time period to ensure fully vaccinated individuals’ immunity remains at an optimum level, says Health director-general Tan Sri Dr Noor Hisham Abdullah.
He said there have been cases of waning immunity after receiving the primary doses within a certain period of time.
"From monitoring done by the Institute for Clinical Research (ICR) in Malaysia, a decrease of 20% in immunity has occurred in fully vaccinated individuals.
"As for Sinovac vaccine recipients, there was an immunity decrease of 40% three to five months after receiving the second dose,” he said in a statement on Friday (Jan 21).
According to him, various studies from Israel, United Kingdom and Chile found a decrease in the level of Covid-19 neutralising antibody after three to six months of receiving the complete primary dose, increasing the risk of contracting the virus, especially for high-risk groups.
Dr Noor Hisham said as of Thursday (Jan 20), a total of 10,235,759 individuals or 43.7% of the country's population aged 18 and above had received booster shots.
Meanwhile, he said a total of 4,046 new Covid-19 cases were reported on Friday (Jan 21), an increase compared to the 3,764 infections reported yesterday, adding that this takes the cumulative number of infections in the country to 2,824,973.
Of the new cases today, 0.8% were in categories three, four and five, while 99.2% were in categories one and two, he added.
"A total of 489 infections were import cases and 3,557 involved local transmissions. There are 149 cases in the intensive care unit with 71 requiring respiratory assistance,” he said.
Also, 2,804 recovered cases were reported today, taking the number of recoveries to 2,750,261, he said.
Dr Noor Hisham also said 12 new Covid-19 clusters were recorded today, adding that there are now 220 active clusters in the country. - Bernama