KUALA LUMPUR, March 7 — The Nigerian Variant B1.525 of Covid-19 has important mutations in the spike protein but they do not affect the ability to detect or trace a person infected with the variant, said Health director-general Tan Sri Dr Noor Hisham Abdullah.
He said this is because existing polymerase chain reaction (PCR) kits use multiple targets to detect variants even though that person can be asymptomatic.
“Currently, no data suggest that this variant is of more virulence or causes increased fatality,” he said in a media statement yesterday in response to questions on the Nigerian variant.
From laboratory study reports, Dr Noor Hisham said, mutation E484K which was also seen in other variants, including the South African (B.1.351) and Brazilian (P.1) variants, had been associated with some level of resistance to neutralising antibodies which were needed to confer protection.
The resistance means a possible reduction in the effectiveness of natural immunity or vaccine-derived immunity against this mutation, he added.
“Mutation D614G causes increased transmissibility due to favourable conditions for the virus to infect permissible cells and replicate.
“Another mutation called Q677H has also been related to a possible increase in transmissibility due to the virus’s efficient binding to human cell receptors,” he said.
Referring to the first two cases of the Nigerian variant in Malaysia, Dr Noor Hisham said it involved a married couple of Indian nationals, aged 36 and 33, who were travelling with their six-year-old son.
He said the husband is a finance professional who has worked for the past two years in Dubai, the United Arab Emirates (UAE) and they travelled to Malaysia as the husband received an employment offer.
“The husband was initially admitted to the Low-Risk Covid-19 Quarantine and Treatment Centre but was transferred to a private medical centre a day later upon his request. He was discharged well on February 9.
“As the wife was in her early pregnancy, she was admitted together with their son to Sungai Buloh Hospital. She was discharged well on February 15,” he said.
Dr Noor Hisham said these two travellers arrived in Malaysia on Jan 31, and the Health Ministry had taken nasopharyngeal and oropharyngeal swabs for RT-PCR at the Kuala Lumpur International Airport (KLIA) as they did not have a pre-departure Covid-19 test.
They were then quarantined at a designated quarantine station and remained asymptomatic; however, the lab-confirmed their RT-PCR results to be Covid-19 positive on February 2.
Dr Noor Hisham said the Institute for Medical Research (IMR) subsequently performed full genome sequencing due to their travel history, and the IMR completed the sequencing analysis on March 4, which showed the two cases had the Nigerian Variant of SARS-CoV-2 (B1.525).