High rate of COVID-19 vaccine approvals in Latin America

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BUENOS AIRES, Argentina — More vaccines have been licensed in Latin American countries than anywhere else in the world. However, there is no linear relationship between the number of approvals in a country and the vaccine coverage of its population, according to a review of the COVID-19 Vaccine Tracker and Our World in Data databases by Medscape Spanish Edition. The number of approvals reflects the difficulties faced by the region in ensuring the availability of sufficient quantities of vaccines, according to experts. One of the reasons for the supply issues is that major countries accepted the first batches that hit the market. Another is that there have been delays in delivering doses promised under the COVAX risk-sharing mechanism.

On February 2, the director of the Pan American Health Organization (PAHO) called the Americas the “most unequal” region in the world. At that time, Latin America had an average of 5.4 approved vaccines per country, compared to 5.0 in Asia, 4.7 in Europe, 3.8 in Africa and 2.3 in Oceania. To put those numbers into context, the United States only has three. In addition, a third of the countries in the region have at least seven approved vaccines; this proportion is 22% in Asia and barely 5% in Europe.

Mexico, with 10 approved vaccines, ranks first in Latin America. In the world, it ranks fourth, behind Indonesia, Iran and the Philippines, which each have 11. On December 12, 2020, Mexico granted its first emergency use authorization to Comirnaty ( Pfizer-BioNTech), and became the fourth country in the world. to endorse this product. Since then, other vaccines — Vaxzevria (Oxford/AstraZeneca), Sputnik V (Gamaleya), CoronaVac (Sinovac), Convidecia (CanSino), Covaxin (Bharat Biotech), Ad26.COV2.S (Janssen/Johnson & Johnson), Spikevax (Moderna), Covilo (Sinopharm) and Abdala, a vaccine from Cuba (Center for Genetic Engineering and Biotechnology) — have been authorized.

However, despite all the options, only 59.8% of the Mexican population has completed the primary series, making it the 11th in the region.

“The government undertook to buy all kinds of vaccines to ensure supply. But this caused logistical problems in terms of administration. We had to combine the vaccines in different ways,” said Alejandro Macías Hernández, MD, infectious disease specialist in charge of the Department of Microbiology and Infectious Diseases at the University of Guanajuato in León, Mexico.

But there really aren’t many findings in the literature on the combined approach. “The main combinations accepted in the literature are for the Pfizer-BioNTech, Moderna and Oxford/AstraZeneca vaccines,” he said. Medscape Spanish Edition. “The other combinations used were based more on ‘real world’ evidence.”

The situation is similar in Argentina, which is tied with Nicaragua for the second highest number of approved vaccines in Latin America. Eight vaccines were approved for emergency use, and one booster, and the use of a heterologous series accelerated coverage.

Comirnaty was the first vaccine to be licensed in Argentina, as in Mexico, but administration outside of clinical trials did not begin until September 2021. The second approved vaccine – Sputnik V, December 23, 2020 – became the cornerstone of the vaccination campaign. in the first half of 2021. The next vaccines to be approved were, in chronological order, Vaxzevria, Covishield, Covilo, Convidecia, Spikevax and Sputnik Light. (The COVID-19 Vaccine Tracker mistakenly includes CoronaVac.)

Forced to explore other alternatives

Argentina has the fourth highest rate of primary vaccine coverage in Latin America, at 77.8%, behind Chile, Cuba and Uruguay, which have six, four and three approved vaccines respectively. Nicaragua ranks 13th, with just over half of its population fully vaccinated.

“The countries that have approved the least vaccines are those that have been guaranteed a very large supply of the first approved vials, in particular of the mRNA vaccine and then of the Oxford/AstraZeneca vaccine. In contrast, Argentina and other countries have had to source other vaccines and explore other alternatives,” said Analía Urueña, MD, director of the Center for Studies for the Prevention and Control of Communicable Diseases at ISALUD University in Buenos Aires. Medscape Spanish Edition. She is also one of the coordinators of the Vaccine Confidence Project Latin America.

In April 2021, the World Health Organization criticized the “shocking imbalance” in the distribution of vaccines and decried the fact that, of the 700 million doses of vaccines administered worldwide, rich countries had received 87, 0% and low-income countries only 0.2%. Vaccine shipments from the Serum Institute of India were delayed due to an outbreak of the Delta variant in that country, which also delayed shipments from COVAX.

Have the many vaccines available led to what marketers call “choice paralysis”? Or could it be that, because there are so many options, people feel that some vaccines are better or safer than others, thereby undermining general trust in this public health intervention? Urueña does not think so because, except in isolated cases, people have been vaccinated with the product that was available in their jurisdiction; unlike the United States, the decision about which vaccine to get was not made at the individual level.

The results of the Bunge y Born Foundation 2021 Vaccine Confidence Study, conducted in Argentina, were presented earlier this month. There does not appear to be a correlation between the number of approved vaccines and public trust, reported lead researcher Guadalupe Nogués, PhD. And, in general, acceptance of COVID-19 vaccines has been found to be very high.

“Vaccination strategies were dynamic and began to show that vaccine interchangeability was not only possible, but also more effective” in terms of immune response, Urueña said. Medscape Spanish Edition. “It helped build confidence that it was not necessary to stick to the same vaccine for all doses in a primary series.”

Other Latin American countries that have an above-average number of approved vaccines are Brazil, Paraguay and Venezuela, each with seven, and Bolivia and Chile, each with six.

The COVAX “fiasco” and market realities

“The problems can be attributed to reliance on a single purchasing mechanism, COVAX, which turned out to be a fiasco,” said Sonia Arza Fernández, MD, head of the Department of Preventive Medicine at the School of Science. from the National University of Asunción in Paraguay.

“Additionally, the authorities’ lack of foresight regarding delivery delays has hampered efforts to seek alternatives to bulk purchases with other countries,” she said. Medscape Spanish Edition.

“So when we found ourselves in the midst of waves of COVID deaths, vaccinating people mostly with donated doses, we felt justified in moving towards approving various vaccines. To this day, we continue to to lag behind in terms of vaccination coverage and purchases through COVAX are not meeting the needs of the country,” she added. According to Our World in Data, only 43.6% of Paraguay’s population has completed the primary vaccination series, which is the second lowest rate in Latin America, just ahead of Guatemala.

The fact that Latin America has a higher number of approvals than other regions of the world reflects the lack of availability of vaccines at the start of the pandemic, said Jarbas Barbosa, MD, PhD, deputy director of PAHO, during a weekly press briefing.

“We had manufacturers who, for market reasons, were looking for stronger markets who were already ready to buy their vaccines. In this situation, many other manufacturers looked to Latin American countries as places where they could submit their products and get approval,” Barbosa said. Recount Medscape Spanish Edition.

The most notable examples are vaccines from Russia and China. To date, Sputnik V has been approved in Russia, two-thirds of Latin American countries, and a handful of European countries (mainly Eastern Europe): Albania, Belarus, Bosnia and Herzegovina, Hungary, North Macedonia, Montenegro, San Marino, Serbia and Turkey.

And with the exception of Honduras and Costa Rica, virtually every other country in the region has approved vaccines developed by Chinese pharmaceutical companies: Sinovac’s CoronaVac and Sinopharm’s Covilo (also known as BBIBP-CorV). As was the case with Sputnik V, these two companies had limited success in bringing their products to the European market.

But diversity has its advantages. “Some remarkable studies have shown that when a country has different vaccines, it can more easily manage vaccination rounds by combining one vaccine for the primary vaccination with another for the third or booster dose,” Barbosa concluded.

By February 15, 1.5 million doses of the Pfizer-BioNTech vaccine, donated by Spain, and 150,000 doses of the Moderna vaccine had been shipped to Ecuador and Haiti respectively, according to PAHO. With these shipments, COVAX distributed 100 million doses in Latin America and the Caribbean. However, coverage remains uneven across the region, PAHO noted.

Macías Hernández, Urueña, Nogués and Arza Fernández did not disclose any relevant financial relationship.

This article originally appeared in the Spanish edition of Medscape.

Follow Matías A. Loewy of Medscape Spanish Edition on Twitter @MLoewy.

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