The increase in cases of covid-19 as of August 29 triggered concern on the part of the public and also the government, which has once again reiterated requests to avoid crowds, parties and other massive events. This Wednesday 29 new cases were detected.

There are those who see the number of active cases (on Sunday it reached 250) and the evolution of new cases per day (18 the average of last week) and compare it with the situation in March, and they are not far (the peak of active in April it was 299, and the week with the most cases, at the end of March, had a daily average of 21). And they even wonder if it’s not time to go back with some openings.

However, the latest wave of positive cases has a striking feature: the very low -almost nil- incidence of serious cases or deaths, a percentage much lower than what the figures indicated so far.

From August 29 to September 15, 271 people infected with covid-19 were registered (the figure does not include 12 foreigners who were tested in Uruguay but then left the country). Those two weeks imply the third highest peak of the disease in Uruguay, after the first due to the marriage outbreak, and the outbreak generated from cases in health institutions, in June.

However, of those 271 cases, there is only one person admitted to CTI.

On August 28, before this latest wave of infections began, there were three patients in intensive care. On September 8 it dropped to two. And since September 10, one remained.

Although in the last week there was the second highest number of active cases since the pandemic reached Uruguay, there is only one person sick with covid-19 admitted to an ICU.

In addition, in these 17 days of the second wave, only one death was registered, on September 4. That is to say: the vast majority of those infected during that period have been processing the infection without symptoms or with mild symptoms that did not require interim care. And there are already 40 infected people in that section who have already been discharged.

In other words, according to the data provided by Sinae, it can be inferred that, in the worst hypothesis, only 0.7% of the cases registered in these 15 days (2) ended up in ICS, and 0.3% (one case ) ended in death. That is in the event that those two cases correspond to people who were infected after August 28, something that the Sinae does not report. Otherwise it would be directly zero.

The figures mark a very strong contrast with the general balance of the disease. According to the latest epidemiological report from the Ministry of Public Health (MSP), which recorded data until August 28 -just before the last wave began-, the figures of hospitalizations in intermediate or critical care reached 3%, and the deaths 2.6%. That is to say, almost nine times more deaths than in this last wave and four times more serious cases.

There is an important caveat and that is that some cases that still have the disease can get worse in the next few days (generally it takes two to three weeks for cases to become serious). In any case, the general trend is for a more benevolent wave than it has been until now.

What happened? There is a sum of variables that are in line with what has happened in other countries of the world, although they have epidemiological realities very different from those of Uruguay.

As the infectologist Homero Bagnulo explained in dialogue with El Observador, the specialized literature refers to four hypotheses that explain this lower lethality.

First of all, diagnoses are being made « earlier » and this helps to care for patients before the disease worsens.

The director of the chair of Infectious Diseases at the University of the Republic, Julio Medina, also referred to the same issue and said that this earlier identification « enables a more adequate care and support » of the infected. Medina affirmed that « timing is very important »: as patients come to be treated earlier, they get worse less.

Along with this, Bagnulo explained that current international treatment in intensive care wards is better than it was when the pandemic began and the disease was unknown. “Instead of intubating them at the entrance, in Europe they go with mask ventilation or even a helmet. This is less invasive, has fewer complications and better results are obtained ”, he assured.

Both Bagnulo and Medina highlighted the learning curve in medical treatment and explained that, as with oxygen management, it was key for healthcare teams to adapt to the use of corticosteroids and anticoagulants.

Second, specialists point to the increase in ITC beds as a factor that decreased lethality. Faced with the need caused by the pandemic, health systems around the world focused on the growth of intensive care units. When hospitals in some countries collapsed, every available bed was one more life saved. In the case of Uruguay, the system had beds available at all times.

The third factor handled by the experts refers to the ages. According to Medina, the specialists noted a « percentage increase in younger patients » among those infected with coronavirus. Bagnulo, meanwhile, assured that a good part of the population at risk in the most affected countries has already died from covid-19. The infectologist said that international studies assure that 25% of elderly residents in US nursing homes have already died and up to 40% in Spain.

Finally, the two experts pointed out that social distancing and the widespread use of masks had a positive effect in reducing deaths from coronavirus. But how, if the infections continue to increase? The answer is in the viral load. In some cases, although the mask cannot prevent infection, it does prevent a high viral load that an infected person transmits to another person. In other words, the amount of virus that passes from one person to another is enough to infect them but –thanks to the mask– not so much as to complicate their health.

International data

In Europe today there is talk of the second wave, and in fact Spain is detecting more cases than in March. However, the death toll, although on the rise, is far from those registered in March.

Europe

Spain

The same happens in the US, where the second wave has already passed, which had more cases than the first and the same number of hospitalizations, but much fewer deaths.

In the case of the United States, there are some peculiarities, because it is not strictly a second wave, but rather, in a giant country, the disease is moving to other regions that had not yet been so hit by the pandemic. The same is true in other large countries, such as Mexico or Brazil.