KUALA LUMPUR: With the growing rate of Covid-19 infection in some parts of the country, experts have called for mandatory quarantine to be implemented.
Like a ticking time bomb, the concern now has shifted to how fast the virus is growing, which is measured by Rt (actual transmission rate at a given time).
Epidemiologist Professor Datuk Dr Awang Bulgiba Awang Mahmud said that Rt should now be the focus for the country in understanding the transmission of Covid-19.
"R0 is R at the beginning of the epidemic when the entire population is susceptible.
"As time goes by, some people would have been exposed to the outbreak, and so we should start using Rt."
He explained that Rt which recorded a reading of 1.0 and above meant the virus would be spreading quickly, while a reading of below 1.0 meant it would stop spreading.
"There are different Rt for different parts of the country, provided that you can get good data for these localities. The Rt for Sabah and Kedah is above 1 at the moment, but not for other parts of the country," he told the New Straits Times.
While cases in Kedah were contained following the Targeted Enhanced Movement Control Order (TEMCO), he said the situation in Sabah was exacerbated following an increased population movement due to the state snap election campaigns as well as an influx of migrants.
"I would suggest that anyone coming back to the peninsula or Sarawak be tested on arrival and quarantined for 14 days, as cases have already been reported in the peninsula which originated from Sabah.
"Most infections have been reported in the east coast districts of Sabah, so very aggressive active case detection (ACD) also needs to be done in those districts," said the Universiti Malaya professor.
"If cases continue to rise quickly and ACD is no longer feasible due to a shortage of resources, then TEMCO may need to be imposed for some districts, but this should be a last resort as there are a lot of socio-economic implications from such a measure."
On when the infectivity rate would be expected to drop again, Awang said it relied on the type of intervention such as ACD to contain the infection in Sabah.
"Covid-19 in Sabah could be contained within a few weeks. If ACD is not possible and TEMCO needs to be implemented in some districts, the process may take longer as we would need to test everyone in the districts.
Malaysian Public Health Physicians' Association president Datuk Dr Zainal Ariffin Omar said it was important to implement the 14-day mandatory quarantine for people arriving from Sabah.
Dr Zainal said the mandatory quarantine should be imposed on anyone who had been in Sabah with or without having them tested for Covid-19.
"The 14 days of quarantine is very important. The person may be negative or positive anytime during the period."
Dr Zainal said although it was possible to lower the R0, the current situation in Sabah was very dynamic with new and active clusters currently on the rise.
"The main concern for Sabah in regard to the virus is the state snap election," he said.
Universiti Putra Malaysia epidemiology and biostatistics expert Associate Professor Dr Malina Osman said the country needed at least six weeks to see a drop in the infectivity rate.
Dr Malina said to reduce the infection rates, the public must continue to adhere to the standard operating procedures (SOP).
"The current situation warrants special attention as there is a sign of an impending new wave in Sabah that has the potential to spread to other parts of the country," she said, adding that she also supported calls for those arriving from Sabah to be quarantined.
Epidemiologist Professor Dr Sanjay Rampal noted that the local transmission cases in the country were still low despite the spike in certain areas, with most Covid-19 cases being imported ones.
"The cases from those who entered the country illegally are a bigger problem here, as the transmission may spread to a few generations before being identified and controlled.
"This multi-generational unabated transmission may help explain the sudden spike in reported cases. The cases may have developed over time, but are only now being diagnosed.
"It is important to establish whether community transmission is high in the localised areas to allow the authorities to increase preparedness and surveillance."
Dr Sanjay said more information was needed on whether community transmission had increased in Sabah in order to warrant mandatory quarantine.
Associate Professor Dr Kamarul Imran Musa said quarantine as well as isolation were two of the most effective measures to contain the transmission of infectious diseases like Covid-19.
"By quarantining everyone who comes from Sabah, we will minimise the risk of infection to be exported to other states.
"However, the better option would be to quarantine individuals who come from the four affected districts in Sabah.
"In addition to that, it is also good to also quarantine those coming from the districts identified as the yellow zones, where there are 1 to 40 positive Covid-19 cases."
To curb the infection from spreading beyond state borders, Kamarul felt that the government should continue to impose strict movement control in the red zone areas while keeping a close watch on yellow zone areas.
"We need to remind the public that the infections in Sabah and Kedah had possibly happened due to community transmission rather than local transmission.
"Community transmission means that someone who is infected by the virus had unknowingly come into contact with confirmed cases, making the source of infection untraceable."
Meanwhile, Dr G. Jayakumar, a professor of Community and Occupational Medicine at the Faculty of Medicine in Melaka Manipal Medical College said it was advisable to make it compulsory for those returning from Sabah to be quarantined at home.
"The authorities may want to impose a two-week quarantine rule for those leaving Sabah when the RO reaches 1.6.
"The focus here is to reduce community transmission and prevent interstate propagation of the virus.
"Additionally, the authorities have to curtail movement of people especially illegals along their porous state land borders," he said.
For Dr Khor Swee Kheng, health systems and policies specialist, quarantine should remain a necessary public health tool as Covid-19 would continue to be around for a while.