SINCE the onset of the Covid-19 pandemic, Malaysia and the world have seen a number of coronavirus variants or mutated strains.

This is not surprising, as viruses tend to undergo mutation and, as such, many Covid-19 variants have emerged since the coronavirus was first discovered at the end of 2019.

Malaysia’s first wave of cases were made up of the B strain. This was the same strain traced in Wuhan, China, the epicentre of the coronavirus.

The country’s first few cases were residents of Wuhan who came to Malaysia for a holiday, where they tested positive for Covid-19.

But since then, Malaysia has seen a number of new strains.

Indonesian strain

Director-general of health Dr Noor Hisham Abdullah said that it is possible that the strain in the Sri Petaling Tabligh cluster originated from Indonesia as there were 692 participants from the country.

The strain was also identified in a sample taken from an Indonesian detainee at an immigration detention centre.

Noor Hisham added that the start of the second wave could have originated from Indonesia.

The cluster reported 3,375 cases.

Variants with the D614G mutation

According to the World Health Organisation, a SARS-CoV-2 variant with a D614G substitution in the gene encoding the spike protein emerged in late January or early February last year.

By June 2020, it became the most dominant form of the virus circulating globally.

“Studies in human respiratory cells and in animal models demonstrated that compared to the initial virus strain, the strain with the D614G substitution has increased infectivity and transmission,” the WHO said.

“The SARS-CoV-2 virus with the D614G substitution does not cause more severe illness or alter the effectiveness of existing laboratory diagnostics, therapeutics, vaccines, or public health preventive measures,” it added.

Many cases and clusters in Malaysia were said to contain strains with this particular mutation.

Noor Hisham said in August that the Malaysian Institute for Medical Research detected the D614G mutation in the samples belonging to three cases from the Sivaganga cluster and one case from the Ulu Tiram cluster.

“It is found to be 10 times easier to infect and is easier to spread, if spread by ‘super spreader’ individuals,” he said.

On October 2, Noor Hisham said the IMR also detected the D614G strain in a few samples in the Benteng Lahad Datu prison cluster in Sabah. However, this particular strain was said to have different traits compared to the Sivaganga cluster and its origins could be traced to Indonesia and the Philippines.

A701V variant

On December 25, Noor Hisham said the A701V variant, which was first detected in the Benteng Lahad Datu prison cluster, had spread to a vast majority of Covid-19 clusters in the peninsula.

“Apart from the most prominent spike mutation, D614G, we are now seeing another form of variant, A701V, which was first detected in the Benteng Lahad Datu (Benteng LD) cluster, and subsequently spread to almost all clusters, including in Peninsular Malaysia and Sabah (post-Benteng LD clusters).”

He said the genome sequence was also spotted in the Teratai cluster, which went on to become one of the country’s largest clusters.

“The virus strain was first found among 22 SARS-CoV-2 sequences from the Benteng LD clusters, and subsequently passed on to the vast majority of third wave clusters in Peninsular Malaysia and Sabah.”

The strain was detected in South Africa, Australia, Netherlands and England at about the same time it was reported in Malaysia.

This mutation has a prevalence of about 0.18%.

UK variant

At least two cases containing the UK B.1.1.7 virus strain have been detected in Malaysia.

Noor Hisham said in January this year that an individual who had recently travelled to the United Kingdom tested positive for Covid-19.

He said the UK B.1.1.7 variant is highly transmissible although it does not cause severe symptoms.

On February 5, Noor Hisham said a second case was detected after a citizen recently travelled to the United Arab Emirates.

The variant, which was first found in the UK, reportedly had 17 mutations.

B.1.470 and B.1.160 variants

On Friday, Noor Hisham said that the B1.470 and B.1.160 variants have been detected in Sarawak.

Currently, there is no evidence to show whether the B.1.470 and B.1.160 variants are more infectious.

Universiti Malaysia Sarawak researchers believe that the B.1.470 is likely to have come from Indonesia.

The virus has the D614G mutation.

Meanwhile, the B.1.160 variant is commonly found in European countries such as France (11.2%), Denmark (28%), Switzerland (15.4%) and the United Kingdom (17.2%). – February 14, 2021.