PETALING JAYA: With the infectivity rate rising to 1.0, health experts believe that the Delta variant, rising workplace clusters and sporadic cases are major contributors to the high number of Covid-19 cases.

Based on the daily Covid-19 reports, Universiti Putra Malaysia medical epidemiologist Assoc Prof Dr Malina Osman said most of the new clusters came from the workplace, contributing to the rising infectivity rate, or the R-naught (R0) value.

“With the presence of the Delta variant and other variants of concern (VOCs), together with poor SOP adherence, more people get infected, ” she said when contacted yesterday.

Although the country had been increasing its vaccination rates, she said the targeted immunisation had to be at least 40% of the population.

“Our target is for the R0 to be less than 0.5. If it is still higher than that, the number of new and active cases will be relatively within the ranges that we have now.

“While the vaccination programme is in progress, all sectors in red zones need to be closed temporarily for at least two weeks or only be allowed to operate if at least half of their employees have been vaccinated, ” she said.

“All those in green zones, or states with one- to three-digit cases, should be allowed to move to Phase Two of the National Recovery Plan (NRP), ” Dr Malina said.

Since the start of Phase One of the NRP on June 1, the R0 levels nationwide dropped from 1.07 to 0.90 on June 12, but steadily rose from June 13 and hit 1.0 by Monday.

The R0 of a virus is a measure of its transmission or number of new infections generated by each case.

For example, an R0 rate of 1.0 means that on average, each infected person will infect one other person they come into contact with.

Universiti Kebangsaan Malaysia health economics, hospital and health management Prof Dr Sharifa Ezat Wan Puteh believed the R0 had not dropped since many private companies were still allowed to operate at different capacities.

She also expressed concern about the VOCs and the variants of interest in the country.

“We don’t really know their prevalence in the community. The prevalence, albeit small at this point, may be bigger than what we anticipate and is concerning, ” she said.

Universiti Kebangsaan Malaysia epidemiologist Assoc Prof Dr Azmi Mohd Tamil said he would not rely on R0 as an indication of whether the infection is under control.He said as long as there were cases in the community, the outbreak would continue unless the majority of the population was immune to the disease.