Divulgação, Notícias

Manaus: chaotic picture and successive records of infections by the new coronavirus

The more people continue to be infected with any variant of the virus, the greater the chance that it will evolve into something even more dangerous and uncontrollable

05/02/2021
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Changes in the Spike protein can affect the transmissibility of the virus, as well as make it more resistant to vaccines developed by different laboratories worldwide

With 1,641 deaths reported in only the first 20 days of February, Manaus, capital of the state of Amazonas (AM), shocked the world with the brutality and monstrosity represented by the loss of dozens of lives by suffocation inside and outside hospitals. For Dr. Jesem Orellana, epidemiologist and researcher at the Oswaldo Cruz Foundation of Amazonas (Fiocruz/AM), the problem in Manaus and perhaps in Brazil, is the lack of public policies aimed at controlling the epidemic outside the hospital. We have to stop the community transmission of the new coronavirus in the population or, at least, keep it at controlled levels, because whoever chooses to control the epidemic inside the hospital ends up opting for death, he points out. Faced with the collapse of the health system, the epidemiologist defended, in an alert released on January 21, the urgent dispatch of an international observer mission, as it is no longer possible to trust the different levels of management that are at the head of the state pandemic.

In December, a study published in the journal Science, estimated that 76% of Manauaras had previously been exposed to the new coronavirus. So how do you explain the second wave that caused the health system to collapse, putting Manaus in an emergency situtation for the next six months? Regarding the estimate, Dr. Orellana clarifies that the study has a serious and common methodological problem in samples of convenience such as blood donors, the selection bias. “As a consequence, the study overestimated the number of possible infected people. For example, the data presented for the possible prevalence of infection in April was less than 5%, a value incompatible with the epidemiological data available in relation to viral circulation at the time, as the month of April was the most critical during the first wave of COVID-19”, he says. Still according to the researcher, this is a fact that can be easily checked in any open-acess database or even in articles already published and cited in the study itself. “Another indication of this problem is the estimate of 52.5% made by that same study for the possible prevalence of infection in June, which is in sharp contrast to the estimate of 14.6% made by EPICOVID-19 in June 2020 (Phase 2), the only population-based study that assessed the seroprevalence of infection in Manaus”, he adds.

The epidemiologist argues that if the estimates for mid-October did not make practical sense, they now make even less. According to him, this is concerning and perhaps it has influenced the decision making of politicians, businessmen and the population, which may have felt endorsed by science, by an article published in the journal Science, one of the most respected in the world. “People believed in herd immunity by the natural route and ended up abandoning social distancing and other measures aimed at containing viral circulation, and the result is what we see now, a second wave marked by explosive and dramatic increase in the number of new cases, hospitalizations and, above all, deaths due to COVID-19”, he laments.

However, that same article criticizes the epidemiological situation in Manaus, stating that herd immunity by natural means cannot be considered an acceptable option. Doctor Orellana agrees with the statement, although he criticizes the percentage of 76% infected in mid-October, considered unreal and incompatible with a second wave as violent as that experienced in Manaus, especially in the month of January, which even had a higher mortality peak than in the first wave. “However, this article brings an interesting contribution that forces us to consider that a considerable part of the individuals who are getting sick now may be cases of reinfection”, he observes.

In the researchers opinion, herd immunity by natural means, at the population level, is an alternative that has proved to be largely unethical and above all inhumane. For him, this is unfortunately a consequence not only of bad management, but of the lack of an effective policy for the control of viral circulation during the pandemic in Brazil and, in particular, in Manaus, as well as of bad science, which creates erroneous expectations and creates an environment of false victory over the virus. The result, according to Dr. Orellana, is that unfortunately we are immersed in what we can consider as one of the worst health and humanitarian tragedies recorded during the entire pandemic, at least so far.

Can the chaotic scenario of Manaus be repeated in Brazil?

The epidemiologist considers it unlikely to have a scenario equal to or worse than that of Manaus, repeating itself in another large Brazilian metropolis. He argues that the state of Amazonas even before entering the pandemic already had disadvantages: wide social inequality; poor infrastructure in health services; little quantity of doctors and nurses per 100 thousand inhabitants; so many other professionals who are needed for specialized care for respiratory infectious disease; lack of beds in the Intensive Care Unit (ICU) in the interior of the state, which overload the medium and high complexity hospital network in Manaus; or even the insufficient number of professionals with medical residency in the ICU.

In addition to this, the bitter state with the historical corruption that dragged on during the pandemic, in addition to fraud, poor management of COVID-19 by those responsible for the Municipality and State, low effectiveness of policies to contain the circulation of the virus, disbelief of the population in the second wave and, finally, a new strain. “These are circumstances that put Manaus in a peculiar situation and, therefore, I see this chaotic scenario as unlikely to repeat itself in another Brazilian city, although it is not impossible. The case is that people need to play their parts maintaining the measures of physical distance, proper use of masks, hygiene, and avoid crowding, otherwise, other cities can be harshly punished by COVID-19 during the second wave”, he says.

New coronavirus variant detected in Manaus

Doctor Orellana recalls that the knowledge we have about the new variant of Sars-CoV-2 is basically due to the surveillance effort of the Ministry of Health of Japan, an initiative that led Brazil to carry out a more in-depth assessment. “From a phylogenetic point of view, the variant detected in Manaus has some characteristics that may be associated with greater transmissibility and this would be the 18th detected in Amazonas. This does not mean that we have 18 variants, but that Laboratory surveillance, in particular, genomics has managed to detect these”, he adds.

Asked why the variant of the Amazon coronavirus is among the three that concern scientists, he explains that this is because it has characteristics that approximate the phylogenetic profile observed in the United Kingdom and South Africa, both associated with greater infectivity.  This is an important issue that concerns not only scientists, but especially decision makers in the area of public health and the population, points out the researcher. Probably, the new variant is one of the components that helps to explain the chaotic scenario observed in Manaus from December to January.

Finally, the researcher recognizes that the concern with this new variant is justified, since there are different medical reports suggesting a greater number of those infected with apparently more serious clinical conditions, including the younger ones. However, Doctor Orellana is categorical in stating that it is too early to make any more forceful assessment in relation to a possible greater pathogenicity of this new variant, since the greater clinical severity of these patients may be influenced by the collapse of the medical-hospital network or by the fact of the disease affecting more vulnerable patients who had not yet fallen ill. “In order to be better understood, we need to carry out further studies, not only to assess the clinical evolution of affected patients, but also to improve the diagnostic capacity, especially of genomic surveillance, essential for the timely detection of new variants and for the confirmation or disposal possible reinfections”, he concludes.