COVID update: Georgia follows Japan trajectory, for now

As COVID-19 infections in Georgia continue to grow slowly but steadily, it is time to take a closer look at how this development compares with the outbreaks in other countries. While Georgia is on the same trajectory as Japan, it currently falls short of the benchmark set by some other wealthy east Asian countries. 
14.04.2020. This is the  conclusion made by Dr. Lorenz HILFIKER, a Swiss mathematician based in Tbilisi. With his kind permission, Caucasian Journal is publishing the findings he posted in his blog, which provides data-focused coverage of the COVID-19 crisis in Georgia.

The first cases in Georgia were confirmed around the same time as in many European countries. Yet, the virus has so far spread considerably less than in most of the Western world.

For example, my native country Switzerland recorded its first case on February 25, just one day before Georgia. Today (April 10) the tally for Switzerland stands at about 24 thousand confirmed cases and one thousand fatalities, while Georgia has recorded merely 230 cases and three fatalities to date.

Here is a chart of all countries which have reached 100 cumulative confirmed cases at least a week ago (thin grey lines).

Сlick to enlarge.    Image (c) Lorenz Hilfiker
A straight line in this chart corresponds to exponential growth with a fixed transmission rate. The steeper the slope of a line, the faster the spread of the virus. The four dashed lines indicate exponential growth where cases double daily, every third day, every week and every two weeks, respectively.

We define day zero for each country as the day when the hundredth case was recorded. Georgia hit that number eleven days ago, and we can see in the chart, that it has managed to keep the speed of the spread rather low ever since. On average, it takes eight to nine days in Georgia for confirmed cases to double. For countries at this early stage of an outbreak, that is a pretty low number. However, Georgia’s almost straight line also indicates, that the country is still in the phase of exponential growth.

Let us look at some other countries. China‘s outbreak gathered momentum way back in January in the city of Wuhan. After an initial phase of very rapid spread (with cases doubling almost every day) Wuhan was placed under lockdown (day 4 on our chart), and drastic measures were taken all across the country. About one week later, we can see the onset of a flattening of China’s trajectory.

Iran, Western Europe and the US were next in line to battle the virus. Their reactions were markedly slower and less decisive than China’s. Correspondingly, the trajectories of those countries are set to peak later and at a higher level than China’s.

Among the countries with more recent outbreaks, Brazil and India do not seem to have been able to use the time factor to their advantage. Despite trailing Italy by almost three weeks, they seem very much on track to catch up with some of the worst-affected countries.

On quite a different trajectory we find Japan, which, due to its proximity to China, has been affected very early on. Despite having little time to prepare, the country has managed to keep the transmission rate at a relatively low level, without suppressing the spread altogether.

Japan is a particularly interesting case from the Georgian perspective, since Georgia is currently following its trajectory with a delay of almost six weeks.

Most strikingly, Japan was able to slow down the epidemic despite avoiding comprehensive testing as well as some of the more restrictive measures other countries are relying on. The New York Times writes, that “part of Japan’s seeming resistance to infection may result from measures common in the culture, including frequent hand-washing and bowing instead of shaking hands. People are also much more likely to wear masks on trains and in public spaces.”

Let us compare Georgia’s trajectory with some more specific groups of countries:
Сlick to enlarge         Image (c) Lorenz Hilfiker
Georgia currently sticks out among all but one of these groups as the country with the most successful response to the coronavirus. However, the benchmark clearly are the wealthy east Asian countries:
  • Infections in Japan, Singapore and Hong Kong have been growing exponentially, albeit at a much slower pace than in Europe before the countermeasures.
  • Taiwan and Brunei managed to almost completely suppress transmission from the beginning.
  • South Korea and Malaysia both experienced an explosive initial spread due to a single event (christian and muslim religious mass gatherings, respectively), but have since been able to slow it down. South Korea in particular, thanks to early rigorous testing and radical tracing and tracking, has flattened the curve in record time.
It is perhaps worth noting, that many of these countries had previous experience with outbreaks of highly infectious respiratory diseases (Hong Kong, Singapore and Taiwan with SARS in 2003, South Korea with MERS in 2015).

Can Georgia repeat Taiwan’s feat of capping the curve before it reaches 500 cases? Or will the upcoming easter celebrations lead to a sudden spike in infections, throwing Georgia onto an entirely different trajectory?

If neither of these scenarios comes to pass, Georgia will continue to trail Japan, with infections growing slowly but steadily. While this may avert disaster for now, it also does not offer an exit strategy. In the case of Japan, this has started to become a problem. Reports suggest a general hygiene fatigue may have set in among the population. A recent new surge of infections has prompted the government to change course and declare a state of emergency on April 7 at last.

All data used in this article is publicly available in the Johns Hopkins CSSE COVID-19 data repository:

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