KUALA LUMPUR, Dec 14 — Those currently undergoing quarantine after returning to Malaysia from abroad will be tested and released on the 10th day if found negative for Covid-19, Tan Sri Dr Noor Hisham Abdullah said today.

However, the Health director-general said other factors will have to be taken into account as well, such as logistical issues.

"We will consider if those under quarantine now can be shortened. We can run tests on the eighth or ninth day, and if it is negative, they can be released on the 10th day,” he said in his daily Covid-19 briefing.

The Health Ministry announced a shorter mandatory quarantine yesterday, from 14 to 10.

The new requirement took effect today.

Dr Noor Hisham said the decision by the ministry was made based on available medical and scientific data.

"There did not appear to be much difference between a 14-day quarantine and 10-day quarantine, so it is an acceptable risk we can take,” he said.

Yesterday, the director-general said the revised quarantine period is in line with the current Covid-19 situation in the country and clinical reports worldwide, adding that several countries have also revised their mandatory quarantine period.

These include the United Kingdom, Germany and Belgium who have all shortened the quarantine period to 10 days, while France has shortened it to seven days.

It is understood the risk of post-quarantine infection will decrease according to the quarantine time period, since the rate of infection is highest in the first week after exposure.