To control spread of coronavirus, let’s throw a dice!

By MUNGAI KIHANYA

The Sunday Nation

Nairobi,

22 March 2020

Why is coronavirus spreading so fast? One of the reasons is that it is not deadly! It kills only a few of those infected. Indeed, the World Health Organisation estimates that the fatality rate is about 3 per cent worldwide. A recent survey in Wuhan, China, where the disease first identified puts it at about 1.4 per cent.

With this low fatality rate, it means that many of the people who get infected get an opportunity to pass it on to others before the virus clears from their body. If there were more deaths, then many victims would be dying before infecting many others.

But the relatively low fatality rate alone does not explain the rapid growth of infections. The spread of all infectious diseases follows a simple mathematical model: the rate of infections is directly proportional to the number of infected people.

In other words, the more the number of infections, the faster the disease spreads. This is what gives rise to an exponential growth in number of infections. It means that, in equal time intervals, the infection rate increases by a constant factor.

It has been observed that, in many countries, the number of coronavirus infections is doubling after every 5 to 7 days. The first patient in Kenya was reported on Friday 13th March; by the time of writing this (Wednesday 18th March – five days later) there were seven confirmed cases.

This works out to an average daily increment of about 48 per cent – a very high rate. If we continue this way without changing our habits, there will be almost 750 confirmed case in Kenya by the end of this month!  For this reason, health authorities need to react very quickly to curb the spread before it gets out of control.

Even though the coronavirus is transferred through physical contact, you don’t need to directly touch the infected person in order to catch it. The infected person may touch a surface and leave the virus there. Then another person touches that surface, picks some of the viruses and transfers them to another surface.

If you touch that second surface, you could get the virus. In short, coronavirus can hop over several people without infecting them and infect the one at the end of the chain.

Since no vaccine is available, it is important to reduce the number of contacts between people. Thus, crowded rooms must be closed and all non-essential travel avoided. This is the reason why the government closed down al schools immediately after the first case was confirmed.

Some countries have resorted to city-wide or nationwide “lock-downs”. Essentially, declaring a curfew. To avoid things degenerating that far, I think it would be wise to declare random public holidays.

The best days would be either Tuesday, Wednesday or Thursday. The Interior Cabinet Secretary can simply throw a dice and, if it falls at, say, the number 3, then declare the following day a public holiday!