The following article by Agustina Sucri appeared on 30 April in La Prensa, a 150-year-old Argentinian daily newspaper. It has been machine-translated from its original Spanish.

Dr. Héctor Carvallo, one of the country’s pioneers together with Dr. Roberto Hirsch in demonstrating the efficacy of ivermectin against COVID early on, did not receive any gratitude for his contributions. Far from that, his studies brought him obstacles and persecutions, attempts to prohibit his research from continuing and his results from being known, threats of dismissal, efforts to displace him, slander, and insults that affected his honor and his professional and academic prestige.

This is what Carvallo claims and today, almost three years after it all began, he has decided to expose the secret plot that was activated during the pandemic to hide the efficacy of this drug — which was already on the market and available at low cost — a plot that has been carried out by the Ministry of Health of the province of Buenos Aires.

Carvallo, who has now reported in the courts the officials involved in the scheme to discredit him, regrets that the drug for treatment and prophylaxis of COVID that he was researching could have saved many lives. “By omission they let many people die,” Carvallo asserts in an interview with La Prensa. “There are 42,000 people who should not have died,” he estimates, referring to the Buenos Aires area alone.

Carvallo was director of the Ezeiza Hospital and head of the Medical Clinic of the same health center, where he worked for twenty years (1984-2004) before it changed its name to Hospital Zonal General de Agudos Dr. Eurnekian and moved to another location. In the interview, this physician, who graduated more than forty years ago, tells us that he was also in charge of the undergraduate students at the University of Buenos Aires.

Once retired, he was summoned from the Eurnekian Hospital to take charge “ad honorem” of the Teaching and Research area, which “was totally dormant”. From then on, he was an “advisor” in that area.

Carvallo says that his interest in the application of this drug for COVID was due to the fact that “since a little before the pandemic, I had been observing the studies that were being done in other parts of the world with ivermectin to treat dengue, Zika and Chikungunya.”


“It was giving good results, at least in vitro. And that was an incentive because to this day there is no treatment or prophylaxis for these three diseases,” he says.

“In Australia, Leon Caly and Kylie M. Wagstaff had no epiphany before they decided to put ivermectin in COVID samples to see what would happen. They were working on dengue, Zika and Chikungunya, and when the pandemic started they just changed the focus of the research but based on the procedure they were already doing. And that is when we found out that ivermectin, in vitro, worked,” he explains.

“Aside from that, it was clear that the severe COVID pictures were from exaggerated inflammation, which requires an immunosuppressant. That is, a corticosteroid. So we made the first presentation on the subject in the journal ‘JAMA’ in March 2020, the title of which was: ‘Ivermectin + Dexamethasone: the ideal combination against COVID?'” the physician recalls.

“Since the journal didn’t publish it, we decided to do the research on our own,” he adds. “We knew at the time that scientific journal publications were sponsored by laboratories, but not that it was such a gross problem,” he notes.

In his review of the facts, Carvallo mentions that money was the main difficulty they faced. “In order to do the in vivo research we needed to have the drug, and we didn’t have any resources. We are independent researchers.

“At that time I was at the Eurnekian Hospital and Roberto Hirsch at the Muñiz Hospital. But we could not ask the directors to authorize the purchase of a drug that up to that time was for scabies, lice, and intestinal parasites, for the simple reason that everything was devoted to the purchase of protective equipment for the staff,” he says.

“Hence, we asked three laboratories — Panalab, Cassará, and Elea — to provide us with a large number of samples and we had to explain to them what we wanted them for. The first two laboratories were very generous. Elea didn’t even answer us,” he describes.

“Hirsch requested authorization to carry out the ivermectin prophylaxis study at the Muñíz Hospital and the ethics committee of that hospital approved it. But when it was submitted to the Ministry of Health, under the charge of Fernán Quiros, it was denied because they asked for requirements that he could not meet,” he explains. Hirsch ended up doing a retrospective study, with the informed consent of those who participated, to overcome the difficulties. “That study was carried out with fewer people than the one we did at the Eurnekian Hospital, but it included a longer observation period, which gives it a fundamental value,” Carvallo points out.

“In the case of the Eurnekian Hospital, we followed the corresponding steps. According to ANMAT at that time, in the event of an epidemic situation, if you were going to investigate a product that already existed in the pharmaceutical market, the steps were: to be approved by the Ethics Committee of the hospital in question and to submit the report to the Central Ethics Committee of the Ministry of Health of the province of Buenos Aires. Before doing that, we had a Zoom meeting with the academic advisor of the Ministry of Health, Dr. Mario Rovere, and we explained to him what we wanted to do. Rovere told us: ‘You have to go out and convince the other hospitals to participate’. This was in March 2020′,” he explains.


“With the approval of the hospital’s Ethics Committee, plus the extra approval of the Ethics Committee of the Municipality of Ezeiza, we started doing two simultaneous investigations: one for treatment and one for prophylaxis,” Carvallo continues.

“We got more than 100 volunteers (staff members and family members) who wanted to do ivermectin prophylaxis and we compared that group with another. Most of them had an average age of 40 years and worked in critical areas — doctors on call, ambulance workers, nurses on call,” he points out.

“The other research was to study the treatment of patients who already had confirmed COVID, for which we had to create a severity table and manage the medication according to the patient’s condition — there were outpatients and inpatients. We made a severity score and studied what dose of medication to give each one and how to combine the drugs,” he continues.

“Out of a total of 32 patients matched against their peers, we had only one death while in the other group there were 8 deaths. That is to say that ivermectin had an efficacy of 7 to 1 against the other treatments being used at the time (convalescent serum, hydroxychloroquine, lopinavir and ritonavir, among others),” he enthuses.

“Out of 134 mild patients, we did not have to hospitalize any, while, in parallel, official statistics indicated that 10% of diagnosed patients, even mild, tended to worsen and ended up hospitalized,” he compares.

These prospective studies began at the Eurnekian Hospital in April and concluded in May, says the researcher.

“In the prophylaxis study,” says Carvallo, “after one month there were 14 cases in the control group and none in the group that took ivermectin as prophylaxis”. It was at that moment, he says, when word began to spread that they were doing this research.

The physician points out that, after obtaining approval, they registered the study on the site, which is part of the U.S. National Library of Medicine. And when the studies were completed, they submitted the results to the Ministry of Health. However, the health ministry did not respond.

“That is why we submitted the results to the National Library of Medicine,” says Carvallo, who emphasizes that these were the first results worldwide for ivermectin in prophylaxis and treatment of COVID.

The researcher’s account includes a visit to the Eurnekian Hospital made in the meantime by Governor Axel Kicillof, the then Minister of Health, Daniel Gollán and his vice, Nicolás Kreplak, who received the results of the studies from the hospital director. “Kreplak replied: ‘Oh yes, I knew they were doing this,'” Carvallo says.