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Confidence in vaccines

Studies show COVID-19 vaccine uptake is high among Brazilians

Alexandre Affonso

Resistance to COVID-19 vaccination has been falling across the country as the immunization program advances, according to a survey by Morning Consult, an international data intelligence company. In April, 20% of Brazilians interviewed said they were unsure or did not intend to get the vaccine. That number dropped to 7% in October, with just 4% certain that they would not to be immunized.

The company has been interviewing residents of various countries since April to monitor acceptance of vaccines against the new coronavirus (SARS-CoV-2). The most recent interviews took place between October 5 and 11, involving some 50,000 people from 15 nations. The results demonstrate a progressive decrease in the level of resistance to the vaccines in all countries, with the exception of Russia. Reticence is higher in many other countries than in Brazil. In the United Kingdom, which took the lead in immunizing against COVID-19, 13% of the population is unsure or does not plan to be vaccinated. The same group accounts for 17% of the population in Germany and 27% in the USA. The USA is doing better than Russia, however, where 43% of the population are unsure or reluctant to get the vaccine.

The relatively greater willingness of Brazilians to be immunized was observed by researchers from several institutions in Rio de Janeiro even before the vaccination campaign began. The group interviewed 173,178 people nationwide between January 22 and 29—which was before Brazil’s National Health Regulatory Agency (ANVISA) authorized emergency use of most of the vaccines available in the country. They found that 154,928 (89.4%) planned to get vaccinated against the novel coronavirus. Of the 18,250 (10.5%) who demonstrated reluctance, only 4,401 were determined not to take the vaccine. “The rest were hesitant, but open to changing their minds,” highlights Daniella Cox Moore, a physician from the Fernandes Figueira Institute of the Oswaldo Cruz Foundation (FIOCRUZ) and one of the authors of the study, published in the journal Vaccine in September.

Alexandre Affonso

Resistance to vaccines against SARS-CoV-2 was highest in the midwest region of the country. The authors analyzed the data provided by respondents to create a more detailed profile of those opposed to immunization. They observed greater reluctance among men aged over 40, with less education, and an average monthly income of less than US$788.68. “Some said they were not afraid of contracting the disease, while others considered the vaccines unnecessary because they had already been infected by the virus,” explains Moore. She points out that men are more likely to expose themselves to risks and reject preventive measures, “which helps explain the greater reluctance among them.” In some cases, the decision was also linked to the country where the vaccine was developed: 35.4% of the 18,250 uncertain participants said they would not take a vaccine produced in China. According to the physician, “this could be the result of disputes between rival political groups or even fake news that accuses the Asian country of having intentionally manufactured the virus to then sell its vaccine as a solution.”

These data reinforce the notion that the phenomenon of vaccine hesitancy—a reluctance, indecision, or refusal to protect oneself, despite vaccines being made available by health services—is not homogeneous worldwide and has different causes. “The reasons associated with this hesitancy are complex and can be particular to the country, vaccine type, or group to which they are being offered,” explains Camila Carvalho Matos, a physician from the Department of Health Sciences at the Federal University of Santa Catarina (UFSC). It may be linked to a lack of confidence in vaccine efficacy and safety or in the motivations of the authorities and policy makers recommending them. “Vaccine hesitancy is high in many African countries,” highlights Matos. “This is partly due to cultural and religious issues, but largely a result of the history of ethical issues related to drug testing on the continent.”

In developed countries such as the USA, France, and the UK, the reluctance is related to the importance of individual freedoms and distrust in the interests of the pharmaceutical industry. A 2019 poll by the Gallup Institute, commissioned by British health foundation the Wellcome Trust, found that one-third of the French population was skeptical about vaccines in general. This sentiment increased after the immunization campaign against the flu pandemic in June 2009, when the World Health Organization (WHO) was accused of being influenced by pharmaceutical companies (see Pesquisa FAPESP issue nº 284).

Even the spread of fake news has not affected Brazilians’ confidence in vaccines

There are also movements in these countries that go beyond denying scientific consensus. According to Yurij Castelfranchi, an Italian sociologist and physicist from the Federal University of Minas Gerais (UFMG), “these European nations are not critical of science itself, but they are concerned about it being used for political and economic gain by governments and private companies.” The phenomenon, he says, is related to the traumatic experiences of Nazism in the first half of the twentieth century and the perceived side effects of industrial development, such as pollution and environmental degradation. “Many Europeans are critical of science and technology while paradoxically being more sensitive to conspiracy theories about the hidden interests of governments and multinationals in relation to the use of vaccines and their possible side effects, especially in the context of crises of confidence in institutions,” explains the researcher, who studies how people perceive and consume science and technology in Brazil and Latin America.

Vaccine aversion took hold in Europe in the late 1990s after British surgeon Andrew Wakefield published a fraudulent article in The Lancet suggesting that the MMR vaccine can cause autism in children. Later studies refuted the connection, and in 2010, more than a decade after the paper was published, it was discovered that Wakefield held shares in a company producing an alternative vaccine. The article was retracted and Wakefield lost his medical license, but the damage was already done.

In Brazil, the phenomenon does not seem to have established an organized movement, as is seen in the USA. “In general, Brazilians are concerned, but they are not opposed to immunization,” says Matos. “Some people reject specific vaccines, but accept others. Some are totally inflexible, while others are open to change. Some, in the end, are willing to get vaccinated, despite their reservations.” Recent studies have found that vaccines added to Brazil’s national immunization program more recently, such as the human papillomavirus (HPV) and rotavirus vaccines, face more resistance than older ones, such as the measles and polio vaccines. “People have this idea that vaccines more recently added to the program have not been tested enough to know their long-term effects,” says the doctor. Some people believe their lifestyle offers them protection, assuming that a healthy diet, physical exercise, or contact with nature is enough to prevent infections.

Alexandre Affonso

Researchers have recently begun to examine the influence of religion on how individuals view certain vaccines. “Uptake of the HPV vaccine is often lower among certain religious groups because it is associated with a sexually transmitted disease,” highlights Matos. There are cases of religious leaders advising their followers against the vaccine and against vaccinating their children because it may encourage them to become sexually active. “Hesitancy in this instance is more linked to people’s attempts to reaffirm who they are and what they believe in than discrediting the importance of vaccines in general.”

Resistance to COVID-19 vaccines is characterized by more specific factors, according to Marcelo Napimoga, an immunologist from the São Leopoldo Mandic School of Medicine and Dentistry in Campinas. One is the speed at which they were developed. “People see the creation of new vaccines as a complex and therefore time-consuming process, which is contrasted by the fact that those now being used against SARS-CoV-2 went through all of the testing phases and began being applied en-masse in less than a year,” he explains. “As a result, groups that are against vaccination, whether for political, ideological, or religious reasons, are skeptical about the safety and efficacy of the vaccines.” One of the Brazilian public’s main concerns identified in the Morning Consult survey is the possible side effects of the vaccines and the speed with which they were developed (see graph above). “Vaccines such as those made by Moderna and Pfizer/BioNTech involve new technologies, another fact that fueled misinformation campaigns,” says Napimoga.

When it comes to trust in vaccines, Brazil stands out among low- and middle-income nations, according to a study published in the journal Vaccines by an international group of researchers in May. The group interviewed 10,491 people from 83 developing countries, including Malaysia, Thailand, Uganda, and the Democratic Republic of Congo. Of the 6,470 Brazilians interviewed, 88.9% said they would be vaccinated against SARS-CoV-2 if the available vaccine had an efficacy rate of 90%. This figure rose to 94.2% if the effectiveness was 95%, the highest among the nations involved in the study.

Alexandre Affonso

The survey results suggest that even political polarization and the spread of fake news and conspiracy theories on social media have failed to affect Brazilians’ confidence in and acceptance of the new coronavirus vaccines. “The main problem is insufficient supply,” underscores Moore. High uptake was essential to Brazil’s successful vaccination campaign, which faced several political setbacks. On October 18, 73% of Brazilians had received one of more doses—one of the highest rates in the world—according to data from the University of Oxford’s Our world in data website. The percentage of the population considered fully vaccinated was was 49.6%.

The situation is different in other countries, including some that have received more doses of the vaccines. Many are still struggling with vaccine resistance among certain groups. Russia was one of the first countries to announce that it had approved a vaccine for the novel coronavirus: Sputnik V. A year later, however, only 32.4% of the population is fully immunized, according to Our world in data. The country’s low vaccination rate has led to a rising number of deaths—the average in September was 800 deaths per day and underreporting is possible.

In addition to questions about the ethical and safety protocols used during the development of Sputnik V, Russian skepticism towards the vaccine stems from a mixture of complacency about the disease and chronic distrust in the authorities, especially among those most critical of President Vladimir Putin’s government, according to Russian sociologist Ekaterina Borozdina, from the Department of Political Science and Sociology at the European University at St. Petersburg. “Vaccine hesitancy in Russia is not due so much to distrust in science itself, but to the long-standing context of tense relations between citizens and the state,” she told The Conversation website in August.

In the USA, reluctance to get vaccinated by people in some states has left the country behind in the global vaccination race, surpassed even by Brazil with respect to the percentage of the population partially or fully protected against the virus. As the more contagious Delta variant spread, the number of daily cases of COVID-19 in the country rose once again, reaching an average of 100,000 per day in August, the highest since February. The majority of new cases and hospital admissions have occurred in Republican states, reflecting the political polarization affecting the nation: regions that vote Republican tend to experience greater vaccine hesitancy. Some groups in the Democratic Party are demanding tougher measures from President Joe Biden to try to encourage vaccine uptake, such as only releasing federal funding to states that meet their vaccination targets.

Brazilians still have great confidence in science and scientists despite recent attacks, according to Castelfranchi

In India, the second most populous country in the world with more than 1.3 billion people, vaccine hesitancy has impaired the country’s immunization campaign, especially in the poorest regions. By mid-October, only 20.2% of Indians had been fully vaccinated. In the state of Bihar, where reluctance is high due to disinformation campaigns on social media claiming the vaccines cause infertility and death, there have been reports of attacks on mobile vaccination centers. Local authorities have been offering household appliances such as refrigerators and fans, and even gold coins to residents as an incentive to get vaccinated.

In Brazil, despite the generally high acceptance, there was some distrust in the COVID-19 vaccines at the beginning of the immunization drive. Wladimir Gramacho, a political scientist from the School of Communication at the University of Brasília (UnB), believes it was linked to political and ideological issues. “Since the pandemic began, political authorities have diverged on the best way of containing it, while members of the federal government have attempted to galvanize their electoral bases by undermining CoronaVac, the vaccine developed by Chinese pharmaceutical company Sinovac Biotech and produced in Brazil by the Butantan Institute in São Paulo,” says the researcher. This affected trust in the Chinese vaccine and acceptance among some of the population, despite it being approved for emergency use in Brazil by ANVISA. Their objections were noted in a study of 2,771 people published in Vaccine by Gramacho and his team in May. The paper showed that respondents were less likely to get immunized against SARS-CoV-2 when told that the vaccine was created in China. “Reluctance was significantly lower for vaccines made in the USA or the UK.”

The situation changed, however, as the vaccination campaign began to advance and the vaccines proved safe and effective. Bruno Luciano Carneiro Alves de Oliveira, a public health expert from the Department of Medicine I at the Federal University of Maranhão (UFMA), says the change is due in part to the public’s memory of Brazil’s successful experiences combating several other diseases through immunization. Another factor that contributed to high uptake among Brazilians was the perceived risks of the disease. “Brazil is one of the countries most affected by the novel coronavirus,” highlights the researcher, who has been monitoring COVID-19 vaccine hesitancy in Maranhão. The number of deaths caused by the disease in the country surpassed 600,000 in October, exceeded only by the USA. “It is reasonable to assume that the fear of infection, in addition to the news about the rising number of cases and deaths and the lack of ICU beds, encouraged people to get vaccinated.” According to Castelfranchi, it is possible that the high acceptance rate is also due to the fact that Brazilians are historically more optimistic about scientific and technological advances than European nations, which are often more skeptical about the benefits. “Compared to Europe and North America, Brazilians have great confidence in science and scientists, despite recent attacks,” emphasizes the researcher.

Scientific articles
Moore, D. C. B. C. et al. Low Covid-19 vaccine hesitancy in Brazil. Vaccine. Vol. 39, no. 42, pp. 6262–68. Oct. 2021.
Bono, S. A. et al. Factors affecting Covid-19 vaccine acceptance: an international survey among low- and middle-income countries. Vaccines. Vol. 9, no. 515, pp. 1–19. May 2021.
Gramacho, W. G. & Turgeon, M. When politics collides with public health: Covid-19 vaccine country of origin and vaccination acceptance in Brazil. Vaccine. Vol. 39, no. 19, pp. 2608–12. May 2021.
Oliveira, B. L. C. A. et al. Prevalência e fatores associados à hesitação vacinal contra a Covid-19 no Maranhão, Brasil (Prevalence and factors associated with Covid-19 vaccine hesitancy in Maranhão, Brazil). Revista de Saúde Pública. Vol. 55, no. 12, p. Apr. 2021.