Coronavirus: we show how big the epidemic can be in Hungary

In recent days, relatively reassuring new coronavirus cases have arrived daily from Hungary. It seems as if the spread of the infection is stagnant, but it is much more that we cannot prove as much as the virus spreads so fast.

Once the testing capacities have reached their limit, we really cannot see a daily number of cases greater than 1000 people, since the country does not conduct more than 10-12 thousand tests on a daily average. Therefore, an increase in the number of cases is only possible if a higher proportion of tests are positive (the epidemic spreads faster).

We have known for a long time that Hungary in the first wave only every 14-15. It is possible that according to the national representative survey, 54,000 Hungarians went through the disease, while at that time we were in 3-4,000 registered cases. In the second wave, the detection rate may have deteriorated. Béla Merkely, rector of the University of Semmelweis, said in early September that roughly every 20 cases had been detected at that time, and epidemiologist Gergely Röst also believed that the detection rate could deteriorate compared to the first wave.

As the rate of symptoms among young people is lower and the virus is spreading among them, I am afraid that our current detection rate has worsened

Röst told Portfolio.

Assuming capacities have reached their limits in the last week or two (ambulances only arrive for tests in 3-4-5 days instead of the 1-2 days before, and that’s enough to wait for test results ), we can assume that the detection rate has deteriorated further. This is also supported by the proportion of positive tests, which has increased from 5 to 6% to 10% in the recent period. If we wanted to keep the rate around 5-6% (which, by the way, already means a high level in itself and indicates a rapid spread of the epidemic), we would have had to do a lot more tests, more tests would have yielded as result more positive cases. The question rightly arises as to why there would be more positive cases, since we could easily get negative results in a series. However, the increase in the number of positive tests may be wrapped up in the number of tests performed because there are currently cases of suspected coronavirus (waiting for the test and the result) that are as likely to get sick as those who have just received their results. in the last days.

In light of the above, we assume that if we increase the number of samples in parallel with the increase in the number of positive cases, we would obtain substantially higher new cases per day. That is, we did not receive an increasing number of cases with a higher level of infection in the population in the data publications of the last days because the number of new tests per day has become relatively low compared to new infections.

To eliminate the problem, we imagine that we increased Hungary’s testing capacities to the last two weeks with a positive positivity rate before capacities are exhausted, eliminating the lengthening of waiting lists. Next, for the sake of simplicity, we calculate what new daily reported case numbers this might have involved. All we had to do was multiply the underdetection rate of 20 obtained by the underdetection rate of 20, and we obtained all the new cases (registered and unregistered), that is, approximately how the epidemic could spread in the country. (The number of actual cases can also be calculated by continuously increasing the undetected rate in parallel with the increase in the number of positive tests and finally multiplying the officially registered cases by more than 20. [jellemzően 21-30 közötti] underdetection rate.)

Based on the above calculation, there may have been between 20,000 and 30,000 new coronavirus cases per day in Hungary in recent days. The actual spread of the disease is shown in the following graph, calculated with a 7-day moving limb:

Although the calculation involves great uncertainty, since in fact no one knows how many of all cases the epidemiological case will find, so another national survey on how many may be infected would be very useful. We also try to delineate the total number of active infections for a case to count as active (infected) for 14 days, so that almost 270,000 active infected people come out.

Another aspect raises the problem of proof capabilities, namely that the proportion of cases in Budapest is constantly decreasing. However, testing is a problem, especially in the capital, and patients have to wait long days in this region. Because ambulances get to the field earlier and infection rates are much lower in many counties than in the capital, they can also better monitor the spread of the virus (relatively more cases are detected per unit of time). Thus, it could have happened that in a few days the share of capital, which had a participation of 40-50% in the daily number of cases, had been reduced to 25% in the last days. This trend also suggests that it would be good to see the real picture more clearly in a representative nationwide survey.