The Argentine Ministry of Health has published a report on the side effects of the Russian vaccine “Sputnik,” which has been used in the country since the beginning of the year. Argentina is the second foreign country to approve the use of this vaccine, and now more than 11 million people have been vaccinated with it.
The data published by Argentina is particularly valuable because Russia does not publish information on the side effects of locally produced vaccines. There is also no official portal with statistics on vaccinated people – statements mentioning the number of vaccinated people are only occasionally made by Russian authorities.
The report is based on data collected through July 31 of this year. In Argentina, Sputnik and AstraZeneca are the two most popular vaccines and have been administered to almost the same number of people. A total of 11.37 million doses of “Sputnik”, 11.1 million doses of AstraZeneca and 9.7 million doses of Chinese Sinopharm were administered to the country’s population.
In the seven months since mass vaccination began, the national health system has registered 50,463 reports of adverse reactions (156.8 cases per 100,000). Of these, 1.99% (1004 cases) were classified as severe, meaning they required hospitalization. The number of serious side effects after the “Sputnik” vaccine is less than 1% of the total. 38,669 cases of adverse reactions after the Russian vaccine were considered non-severe.
The majority of reports on various side effects were received for “Sputnik”, for AstraZeneca – 2999 reports, for Sinopharm – 2384. Another 3535 cases were not related to any of the vaccines.
Published in Argentina and the distribution of the number of serious side effects depending on the vaccine: 72% of adverse event reports were from women, and the median age of those reporting adverse events was 42.4 years for both sexes.
The report highlights that the response rate of the surveillance system to adverse events was very high at the beginning of the vaccination, because the vaccines were used in pandemic conditions and were all new. In other words, health workers were trained to recognize and report adverse reactions quickly.
Although the number of doses administered to people has increased over time, the number of reports of serious side effects has remained low, according to the Argentine Ministry of Health.
The most common adverse reactions reported after “Sputnik” were headache or muscle/joint pain (136.2 cases per 100,000). There were also cases of fever with headache and/or muscle/joint pain (128.5 cases), local reaction without fever (presumably referring to redness at the injection site – BBC) – 26.9 cases per 100,000. I rarely encountered a high temperature – 16.5 cases per 100,000, local pain – 11.4 cases, local reaction with fever – eight cases, gastrointestinal tract reactions with or without fever – six cases, and the same – allergies.
Very rare side effects of Sputnik include local lymphadenopathy (enlarged lymph nodes – BBC) – such cases occurred at a rate of 0.83 per 100,000, anaphylaxis (0.10 per 100,000), metallic taste in the mouth (0.08), and hyperthermia (0.05). Nine cases were classified by the Argentine Ministry of Health as indeterminate, meaning they could not be definitively linked to vaccination. These included three cases of Guillain-Barré syndrome (an acute autoimmune inflammatory reaction), five cases of various thrombocytopenias, and one case of pericarditis (inflammation of the serous membrane surrounding the heart).
The authors of the report emphasize that data on side effects may change and be clarified as new information emerges.
At the end of August, Argentinean scientists published a preprint of a study concluding that the neutralizing activity of antibodies after the “Sputnik” vaccine increases over a six-month period in those who have not been previously infected with the coronavirus. The researchers took serum samples on the 42nd day after the “Sputnik” vaccination and found that they were less effective in neutralizing the “beta” and “gamma” strains compared to the original Wuhan variant. However, after 120 days of vaccination, the situation changed: the neutralizing activity against the “alpha”, “beta”, “gamma” and “delta” variants was higher compared to the Wuhan variant. The “lambda” variant (discovered in Peru late last year) had slightly lower neutralizing activity. Scientists have summarized that although levels of IgG antibodies to the virus decrease over time, the effectiveness of virus neutralization in vaccinated (previously uninfected) individuals increases. This suggests that antibody maturation occurs several months after vaccination. These are preliminary conclusions and the study has not been peer reviewed.
In Argentina, statistics show that more than 60% have been vaccinated with the first dose and 33% have been fully vaccinated. In late June, it was reported that the country was experiencing problems with the second component of the “Sputnik” vaccine – it had not been available for several months. It was reported that Argentine authorities were negotiating with Russia to obtain a shipment of the second component, as many Argentines who had received their first dose in March-April were still waiting for the second injection in June. After Argentina threatened to cancel the contract, Russia sent a shipment of vaccines to the country, but it contained only 400,000 doses out of an expected 18.7 million. Russian authorities then said their priority was domestic consumption. “At the moment, it is not possible to immediately satisfy the entire demand abroad, but in time all obligations will be fulfilled,” said the press secretary of President Dmitry Peskov.
In Argentina, they have started their own production of the vaccine and have also stated that they can substitute the second dose with AstraZeneca or CanSino vaccines, which also use adenoviral vectors. At the end of August it became known that the Argentine company Richmond had produced over 5 million cans of “Sputnik” since June – the company’s press service reported on Twitter. “We have surpassed the mark of 5 million doses produced in Argentina, including the batch completed yesterday. Currently, we have produced 1,179,625 doses of the first component and 3,890,000 doses of the second component,” the release said.