KUALA LUMPUR, Feb 7 – Omicron became the dominant coronavirus variant in Malaysia about a month ago, comprising 80 per cent of sequenced Covid-19 cases on January 10.
According to Our World In Data, Omicron went from 0.25 per cent of sequenced Covid-19 cases in Malaysia on November 29 last year and to 4 per cent on December 13, before a rapid spike to 65 per cent in just a fortnight later on December 27.
In another two weeks, Omicron comprised 80 per cent of sequenced cases on January 10, replacing, as the dominant strain, Delta that formed the remaining 20 per cent.
These numbers may not reflect the complete breakdown of reported Covid-19 cases in Malaysia since only a fraction undergo genome sequencing.
According to the global GISAID database, Malaysia sequenced and shared just 0.5 per cent of 390,515 reported Covid-19 cases in the last 90 days, or 1,984 sequences.
Other ASEAN countries sequenced a bigger proportion of their reported coronavirus infections in the past three months, such as Cambodia (30.5 per cent), Brunei (15.1 per cent), Indonesia (2.6 per cent), Singapore (2 per cent), and Thailand (0.9 per cent).
Daily Covid-19 cases in Malaysia surged to 10,089 yesterday, the highest 24-hour increase since October 2 with 10,915 infections.
According to the CovidNow site, Malaysia’s seven-day average is currently 6,891 Covid-19 cases, a 46 per cent increase from a week ago, with the positive rate jumping to 5.5 per cent.
A positive rate exceeding 5 per cent shows the likelihood of more Covid-19 infections not being captured in testing and surveillance programmes. All states, including the Klang Valley region, recorded positive rates at 5 per cent and above, except Terengganu, Perak, Labuan, and Sarawak.
Prof Dr David Pereira, who is director of Universiti Malaysia Sarawak’s (Unimas) Institute of Health and Community Medicine (IHCM), said in a statement yesterday that Omicron comprised 78 per cent of 58 sequenced Covid-19 cases in Sarawak from January 3 to 26. Of the sample, 45 Omicron infections were detected, compared to 13 Delta cases.
“The 78 per cent detect rate suggests that Omicron has replaced Delta as the dominant circulating variant in Sarawak,” Dr Pereira said in the statement released by Sarawak Disaster Management Committee chairman Douglas Uggah Embas’ office.
Dr Pereira said the Omicron cases were detected in samples taken from Kuching, Samarahan, Sibu, Kapit, Mukah, and Miri.
He also said the majority of Omicron cases were of the BA.1.1 lineage, but three cases of the more infectious BA.2 sub-variant were identified in Kapit.
“Most of these cases had happened through community transmission.”
The BA.2 version of Omicron, dubbed as the “stealth” sub-variant, does not have the same missing target gene as the BA.1 sub-variant that could be identified from common RT-PCR tests. This means unlike BA.1 cases that could be easily presumed Omicron from PCR testing, BA.2 can only be picked up from the more time-consuming genome sequencing.
BBC reported a Denmark study that found BA.2 was “substantially” more transmissible than BA.1, but a separate UK study found no evidence that Covid-19 vaccines would be any less effective against symptomatic disease for either the BA.2 or BA.1 sub-variants. Data so far also does not show that BA.2 leads to more severe illness than previous Omicron sub-variants.
