Mthabisi Tshuma, Chronicle Correspondent
HEALTH experts yesterday said the 21-day national lockdown that starts today is vital in curbing the spread of coronavirus as it allows infected people to show symptoms, get treatment and heal within that period.

President Mnangagwa on Friday declared a total lockdown on the country from today until April 19 in order to contain the spread of Covid-19 which has infected more than 500 000 people worldwide. The country has recorded seven positive cases, with one of them having succumbed to the disease.

Other countries in Africa who have activated the 21-day lockdown are South Africa and Rwanda while Nigeria and Kenya have increased their curfew hours.
Mpilo Central Hospital clinical director, Dr Solwayo Ngwenya said the scientific way of a 21-day lockdown is that usually people show symptoms of coronavirus within 14 days which is called the incubation period.

“So, if someone gets a virus today, it won’t show until at least ten to fourteen days later. Now the 21-day period is to say people who got infected yesterday for example, are going to show signs during this period. This is because everyone is locked down and unable to move around.

“Around day 13 or 14 of the lockdown, these people will now be ill and they will then seek medical attention and will be removed from the community and taken to centres of isolation where they will be treated. Therefore, by removing them they haven’t moved around the community as they were contained in their house,” said Dr Ngwenya.

“Now that they are taken away the other members of the family will also start showing signs and hopefully all of them will show symptoms within the 21-day period. Then when these people have been taken away if the rest of the community is allowed to move around, the scientific thinking is that the infection has  been curtailed.

“What happens is that this 21-day lockdown slows down the infection rate because you have removed people and taken them to isolation centres and they haven’t been able to infect as many people as if they were freely roaming around.

“You may be forced to do another cycle of 21-days or more to contain the virus according to how it is remaining in the community. So over time, the virus keeps being suppressed because less and less people are passing it onto the next person thus that’s what the scientific way of a lockdown is.”

National University of Science and Technology’s Applied Genetics Testing Centre (AGTC) director Mr Zephaniah Dlamini said:

“Symptoms show after 14 days thus let’s assume that someone has been infected in the last seven days or today, so within 14 days he/she will be showing symptoms. So it’s best to then isolate everyone then if there are those who are infected they will show symptoms and will be quarantined and treated. If they are left to interact with other people they will be infecting them without knowing,” said Mr Dlamini.

The Hindu Times of India quoted Tamil Nadu’s director of Public Health K. Kolandasamy saying, “In epidemiological terms, the logic is that we have arrived at an incubation period of 14 days. Give another week for the residual infection to die out, for the tail end, to be entirely safe, and you arrive at 21 days.”

A new research published in the journal “Annals of Internal Medicine” and titled “The Incubation Period of Coronavirus Disease 2019 (COVID-19) From Publicly Reported Confirmed Cases: Estimation and Application” concluded that the median incubation period for COVID-19 is just over five days and that 97.5 percent of people who develop symptoms will do so within 11.5 days of infection.

“Researchers headed by Nicholas Reich, Associate Professor in the School of Public Health and Home Sciences, University of Massachusetts, Amherst, reportedly examined 181 confirmed cases with identifiable exposure and symptom onset windows to estimate the incubation period of COVID-19.

“They conclude that ‘the current period of active monitoring recommended by the U.S. Centers for Disease Control and Prevention [14 days] is well supported by the evidence,” said the report.