Mexico City Officials in Row Over ‘Misleading’ Paper to Justify its Ivermectin Drive

Mexico City officials have been dishing out the animal worm treatment, ivermectin, to citizens with COVID-19 – and published a paper in which they apparently attempted to manufacture evidence that the treatment could reduce COVID-19 hospitalisation to justify their actions.

The paper was removed from the social science platform, SocArXiv, last week for trying to provide justification for “a government program that unethically dispenses (or did dispense) unproven medication apparently without proper consent or appropriate ethical protections according to the standards of human subjects research”, said the platform’s steering committee.

Until 4 January, the Mexican Institute of Social Security (IMSS) had included ivermectin as part of free COVID-19 care kits given to citizens who tested positive for COVID-19 – spending over $1,4million on the treatment, according to Animal Politico.

Ivermectin is mainly used to treat parasitic worms in animals, and is only approved for human use to treat certain parasitic worm infections, head lice and skin conditions like rosacea. 

Merck, which makes ivermectin, has warned that there is no scientific basis to use its medicine to treat COVID-19, while the World Health Organization (WHO) and other regulatory bodies have also stated that there is no evidence that the treatment has an effect on the coronavirus and could be harmful in large doses.

Ivermectin has been promoted as a COVID-19 treatment by conspiracy theorists and anti-vaxxers who claim that “big pharma” has tried to prevent recognition for the medicine as it would undermine their vaccine profits.

Between December 2020 and December 2021, the IMSS dished out 465,345 kits containing ivermectin to people with COVID-19 in Mexico City, the department told Reuters.

Mexico City Secretary of Health Oliva López was one of the paper’s authors.

‘Misleading and false’ paper removed

The row deepened last week after a paper authored by officials from the Mexican Social Security Institute and the Mexico City Ministry of Health – purporting to provide evidence that ivermectin can reduce hospitalisation – was removed from SocArXiv. 

On 4 February, SocArXiv director Philip N Cohen announced the withdrawal of the paper from his platform, which allows social scientists to share papers that have not been peer-reviewed.

Previously, the ​​steering committee of SocArXiv had said that “the article is of very poor quality or deliberately false and misleading”, but said that they had never removed an article and had no policy to do so.

However, they took action after an appeal by University of California-San Diego sociology professor Juan Pablo Pardo-Guerra, who described the paper as “deeply problematic and unethical” – along with the fact that the paper was proving to be hugely popular with readers and had been downloaded over 11,000 times.

According to Pardo-Guerra, the authors – including Mexico City’s Secretary of Health, Oliva Lopez  – had unethically recruited experimental subjects without their informed consent, and used dubious and unscientific methods. 

Generating false ‘evidence’

University of California-San Diego sociology professor Juan Pablo Pardo-Guerra

Pardo-Guerra wrote a blog about the incident last Friday, in which he accused the officials of “actively [generating] false evidence in order to justify their actions”. 

Pardo-Guerra contends that government officials decided to manufacture “evidence” of ivermectin’s efficacy in reducing COVID-19 hospitalisations to justify their expenditure in the face of mounting research proving that the medicine offered no benefit against COVID-19.

“In May 2021, the head of the Digital Agency for Public Innovation, José Merino, presented a small article, signed by him and other officials, as strong evidence supporting the actions of the capital government,” said Pardo-Guerra, who proceeded to pull apart the study.

As the ivermectin kits were not distributed in a randomized, controlled fashion, Merino and his coauthors used a “matching” technique to compare the hospitalization rates of those who received ivermectin with those who did not, simply by finding “similar people” based on sex age, symptoms, and comorbidities, said Pardo-Guerra.

“Without randomized controlled trials, it is simply impossible to say that the reported effects (decreased hospitalizations) are really products of the treatment or result from some other variable that was not considered,” he added.

“The kits also included aspirin and, given the intervention and analysis, it is impossible to know whether the reductions in hospitalizations were the effect of aspirin, ivermectin, or the graphic design of the kit.” 

Pardo-Guerra concluded: “Merino’s article, wrong in its design and analysis and immoral in its way of producing data, has been downloaded more than 11,000 times and is frequently cited on pages of dubious affiliation: from anti-vaccines, from private organizations that sell alternative treatments against covid-19 and other nefarious corners of the internet.”

In response, Merino has requested a hearing with the ​​steering committee of SocArXiv to address their concerns, claiming that they had not raised issues with the paper’s methodology. However, Cohen, the platform’s director, described his complaint as “noise” and added that if he was so confident of his methodology, Merino should send his paper to a peer-reviewed journal.



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