[ad_1]
The model estimated official figures for the United States, Australia, Canada, South Korea, and 11 European countries. It can be concluded that these figures are far behind the real ones and cannot show the real extent of the prevalence of the infection.
The authors of the model, Australian researchers, used a method called “backcasting”, which projects the number of new deaths per day in reverse, from the time of death to the time of infection. This allows researchers to avoid the use of epidemiological and serological data, which is limited by the scope of the evidence.
And by comparing the numbers in their model with the official numbers of confirmed cases, the researchers predicted the “true” number of infections for each state. According to his calculations, at the end of August, the number of infections in the population was on average 6 times higher than officially announced.
“Unlike the reported cases of infections calculated from RNA testing, the fallback method does not depend on the coverage or capacity of the testing regimen, which can vary greatly between jurisdictions or over time,” said the authors of the study.
This means that this method is much easier to apply regionally, nationally or even internationally than other methods. Furthermore, it is not dependent on the testing regime applied by a particular country and thus can help public health professionals prepare for more active work in regions where testing opportunities are limited.
“Broadly speaking, we looked at statistics on the number of people who died from COVID-19 in a particular country and traced this data down to the number of people who had to be infected to suffer that death,” said Steven, a researcher at Ikigai Research in Australia. Phippas.
“Our method is a new and easy-to-use method to determine the true extent of infection when there is reliable data on COVID-19-related mortality,” said the researcher.
In some countries, infection rates are better than in others. For example, in South Korea, the number of “real” infections was found to be “only” 2.6 times higher than officially reported, while in Italy the number of retrospectively calculated infections was as high as 17.5 times. higher than in statistical summaries.
Collectively, countries around the world have improved their ability to screen the population for COVID-19 since March, better informing citizens about the symptoms of the disease, finding increasingly accurate ways to diagnose the disease and track its spread.
Despite these lessons learned, international figures are far behind “real” figures. Even in Australia, where the detection rate of infected people is one of the highest of all the countries included in the study, the researchers say that the actual detection rate of the virus is almost 5 times lower than the “true” level.
“We have found that COVID-19 infections are much more common than confirmed in many parts of the world, which is very important for both pandemic control and the likelihood of infection.” Our findings raise serious questions about how We deal with all sides of the coronavirus pandemic, including morbidity and damage to the long-term health of infected people, how we enforce and control quarantine conditions, and how we generally make sure to fight the pandemic successfully, “he said. an economist from the Australian National University Quentin Grafton.
By the way, this is not the first time that scientists have discovered a large discrepancy between the number of officially published COVID-19 cases and the actual situation. In practice, since the beginning of the spread of this virus, experts have warned that we are probably underestimating the true prevalence of the virus.
And when testing levels are limited, it is difficult to even determine that a patient has died of coronavirus, as symptoms of this viral disease often overlap with symptoms of chronic disease in the most vulnerable and respected age groups.
Many statistical studies to date have compared the total number of deaths recorded in 2020 with normal death rates in any other year, or antibody tests have identified deaths that were not included in the baseline COVID-19 victims because it is They may not have symptoms of this viral disease.
Most epidemiological models conclude that the actual number of infections is much higher than the number of officially reported cases, but there is little consensus on how much these numbers vary and how that difference varies over time.
Epidemiological data are limited by country-specific testing levels and policies, and antibody tests report a relatively high number of false positive and false negative cases, meaning that even if the number of false positive cases in a country is low, even a few miscalculated results can seriously skew the data.
Calculations from another US study found that the number of people infected in that state in April was 3 to 20 times the official number of cases, largely due to insufficient levels of evidence and, to a lesser extent, , to an inadequate test precision.
Another study, based on antibody tests in the US, showed that the actual level of SARS-CoV-2 infection in May was 10 times higher than officially announced.
The calculations according to the new model were carried out only in high-income countries, where the population tests were sufficiently intensive. But in most of the world, the population tests for COVID-19 are much lower, indicating that the actual number of people infected with COVID-19 is many times greater than the official rate in the world population.
In some countries, such as Belgium, France, Italy and the United Kingdom, the actual infection detection rate has been found to be very low. 2020 August 31, the official figures published by these countries were only 10%. The “actual” number of COVID-19 cases provided by the new analysis.
It is true that it is not yet possible to select a particular way of identifying statistical cases and say that it is the true, unique and ideal; all statistical methods should be seen as complementary, forming a general picture.
Furthermore, epidemiological models so far predict the number of hospitalizations much better than this counting method used by data researchers, and the authors of the latest study fully acknowledge this.
It is also important to note that for the countdown model to be accurate, the age distributions of people infected with COVID-19 must be roughly the same, as older people infected with the disease are more likely to die. . Age dependence on mortality can distort the statistics, as in Australia, for example, by up to 75%. Deaths from COVID-19 were recorded in nursing homes.
Finding the most accurate method to make a good assessment of the past, present and future of COVID-19 cases will take some time. And it is quite possible that it will not even be possible to know exactly how many people will get sick during this pandemic.
On the other hand, an accurate calculation of the actual COVID-19 burden is essential to adequately prepare for this pandemic.
The results of the study were published by the Royal Society Open Science.
[ad_2]
