Mexican
scientists
specialized in mathematics, statistics, and infectious diseases warned the country might present up to 25 more COVID-19 cases than those confirmed by test kits. This would imply that there are between 881,000 and 1,270,000 Mexicans infected with the new virus; most of them would show no symptoms but can infect others.
The data comes from calculations made by scientists consulted by EL UNIVERSAL . On this vein, Alejandro Macías , considered the top expert of the H1N1 epidemic of 2009 when he was the national commissioner for the Prevention and Control of Influenza of Mexico’s Health Ministry (SSA), explained that as long as there are no laboratory tests to look for antibodies in the blood of people, as happened in New York, the exact number of infections will be unknown.
Nevertheless, he considered that due to the measure of the disease and its spread, the country currently has over 1 million people infected with COVID-19.
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“In Mexico, we will hardly have less than 1% of the national population infected with the coronavirus . I don’t think it will be less than that and there will hopefully be more infections so that people have antibodies. If we’re 127 million people , at least 1,270,000 could be already infected in Mexico. This number can be controversial but if I say that 1% of the population is infected no one is surprised and it doesn’t matter,” he stressed.
Arturo Erdely Ruiz
, professor of the Acatlán School of Higher Studies (FES), calculates that the new disease can be 23 times bigger than what is registered in the latest projections published by the SSA on May 3.
The number is obtained from applying an expansion factor of 23 times that implies the number of cases confirmed by tests. Estimates say that there could be over 881,452 contagions in the country. Most of them can be carriers of the virus but show no symptoms, which does not prevent them from being infected.
“This factor was initially set at 31.3 times but it has decreased. The last time I calculated it with the information provided on May 3 , it was around 23 times. That is the relation we can have between confirmed and estimated cases. Most of the expected cases are mild ; the minority will be serious and will require hospitalization,” the expert explained to EL UNIVERSAL.
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On May 3, the SSA said that, according to the Centinel model , there were 104,562 confirmed COVID-19 in the country. This system is a kind of survey implemented by the federal government to identify coronavirus cases in 475 health units that monitor the respiratory disease. Its objective is to collect high-quality data instead of collecting a great amount of low-quality information.
By dividing the 104,562 estimated cases between 4,524 confirmed cases as of May 3, the multiplication factor calculated by Erdely was of 23 estimated COVID-19 cases for every confirmed case.
“According to the factor I propose, I calculated that Mexico will have some 900,000 estimated contagions by Tuesday. We must not fear; they are mild cases; some have already recovered. What we’re saying is that, by the end of the year, Mexico could have 1.8 million cases, ” said the mathematician.
The expansion factor can vary depending on the evolution of the pandemic, but the SSA is no longer including in its daily report the data that would help scientists make precise projections .
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Gustavo Cruz
, a member of the Institute for Applied Mathematics and Systems Research (IIMAS) told EL UNIVERSAL that the number of cases is not registered with precision, however, this happens all over the world, where the expansion factor has reached up to 50% , which can still happen in Mexico.
“ We calculate the expansion factor for the number of contagions between 50 and 80, but, I stress, it’s a very big number because it includes people who get infected and never show symptoms , those who never noticed they were infected .” He added.
“The figures presented by the government are only from those people who arrive in health services . What I’m saying is that for every one of them, there are nearly 50 who never receive medical care and infect others. This is a projection we made at the beginning of the pandemic in China and other Asian countries ,” he said.
Since April 8 , the SSA revealed that there are more contagions in the country than what it is possible to confirm through laboratory tests . By applying an expansión factor of 8.4 , it calculated back then that there were 26,519 cases although only 3,181 had been confirmed with laboratory tests.
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