INTRODUCTION

On June 7, 2021, the World Health Organization (WHO) reported 173,005,553 confirmed cases of COVID-19, including 3,727,605 deaths ¹. With no effective treatment and few therapies to modify the course of the disease, the global hope of controlling the disease rests on the effective and universal distribution of available vaccines ².

Vaccination is key for succeeding in controlling the disease ³. Despite the growing number of safe and effective vaccines on the market, reluctance to vaccinate is a growing problem with global implications ⁴. This has become an important phenomenon due to outbreaks of preventable diseases that were previously controlled with vaccines ⁵. In the context of the COVID-19 pandemic, vaccination acceptance is a relevant discussion due to misinformation, mistrust and conspiracy theories that have hindered the adoption of community mitigation measures against the disease, such as vaccines ⁶.

There are several studies related to the acceptance of vaccination against COVID-19. Some countries such as China, United States, Ecuador, Malaysia, Indonesia, South Korea, Brazil, South Africa, Denmark and United Kingdom have a high acceptance rate, between 65% and 97% ^{7 - 10}. In contrast, other countries have low acceptance rates, between 55% and 62%, such as Russia and France ^{11 , 12}. Vaccine acceptance varies according to sociodemographic factors such as gender, belonging to ethnic minorities, rural population, economic income or sociological factors such as political tendencies, among others ^{6 , 10 , 13 - 16}. We recently reported that countries from Latin America and the Caribbean intended to vaccinate 80% of their population by February 2020; and that fears of becoming seriously ill, having a family member fall ill from COVID-19 and having depressive symptoms were associated with a higher probability of having the intention to be vaccinated ¹⁷. In contrast, being female and non-binary was associated with a lower vaccination intention ¹⁷.

Peru has been one of the countries most affected by the COVID-19 pandemic. According to the situation room of the Peruvian Ministry of Health (MINSA), more than 1.9 million cases and more than 186,500 deaths due to COVID-19 were reported by June 7, 2021 ^{( 18}. On February 7, 2021, the first batch of vaccines arrived in Peru, initiating the vaccination process against COVID-19. Although more than four million doses have been administered to date ¹⁸, the vaccine is not fully accepted in Peru, as in other parts of the world. According to a survey published by Ipsos in February 2021, if a free vaccine against COVID-19 were available, 35% of the country’s population would not get vaccinated, the first reason being fear of adverse effects ¹⁹. A previous study conducted by the authors on the vaccination intention in Latin America and the Caribbean did not include variations at the departmental level, in order to identify aspects that could individualize vaccination strategies in each of the departments of Peru ¹⁷. Therefore, the aim of this research was to determine the prevalence and factors associated with the intention to be vaccinated (ITV) against COVID-19 in Peru.

MATERIALS AND METHODS

RESULTS

Prevalence of the intention to be vaccinated by departments

The departments with the highest ITV prevalence were provincial Lima (81.4%), metropolitan Lima (77.7%), Junín (76.7%), Callao (75.7%), Huancavelica (75.7%) and Loreto (75.7%). On the other hand, those with the lowest ITV were Madre de Dios (53.9%), Ayacucho (66.1%), Puno (69.5%), Ucayali (69.9%) and Tacna (70.2%) (Figure 1).

Figure 1 Prevalence of vaccination intention according to Peruvian departments 

DISCUSSION

Our results show a high ITV against COVID-19. This is similar to what was found in a multinational study that included Brazil and found that 71.5% of its participants reported a very high or some likelihood of accepting the COVID-19 vaccine ¹¹. In this study, acceptability varied by country, ranging from as high as 90% in China to as low as 55% in Russia ¹¹. Other studies in different countries have also shown different acceptance rates ^{7 , 14 , 22}. The variability among these results may depend on how the research question is posed, which limits comparability ¹⁴. For example, a multinational study conducted by the Imperial College of London in November 2020 asked whether there was a “definite intention” to get the COVID-19 vaccine, with responses ranging from 18 to 65% ²². Our study does not pose the answer in terms of a “definite intention”, which would explain the lower percentages.

The variability in the results may also be due to the timing of the study ¹⁴. In the United States, the acceptance rate ranged from 72% in April to 48% in October 2020 ¹⁴. In Italy, vaccine acceptance increased after confinement ²³. In Peru, the Ipsos survey showed that the percentage of Peruvians accepting vaccination decreased from 75% in August 2020 to 59% in February 2021 ¹⁹. The differences found between that survey and our study could be because confidence increased over time due to the advent of vaccines and more information available about vaccines ²⁴. A previous study in countries in the Latin American and Caribbean region, which used the same source of information as this study, reported that the country with the highest ITV was Mexico (88.4%) and the lowest ITV was Haiti (43.2%) ¹⁷.

Likewise, it is possible that as the risk perception increased in the country, so did the ITV ^{14 , 23}. In the weeks prior to the survey, due to the increase of the number of cases and deaths ¹⁸, the news of the lack of oxygen and available hospital beds may have increased the sense of vulnerability and, with it, the acceptance of the vaccine. A study in Turkey showed that 40% of those who initially had doubts about the vaccine considered it necessary as the pandemic progressed ²⁵. Similarly, in France, more nurses shifted from rejection to hesitancy or acceptance of the vaccine ²⁶.

Similar to our study, other countries show lower ITV in women ^{14 , 27}. Although the reasons for these gender differences are not entirely clear, a European multinational study suggested that it might be due to women showing more concern regarding adverse effects and vaccine safety than men ²⁷.

Although few studies have included rural populations ¹⁴, some aspects may explain our finding: living in a village or other rural area was associated with lower ITV. Rural residents are often reluctant to seek medical care or engage in preventive health behaviors compared to urban populations ²⁸. Similarly, difficult access to the Internet limits telemedicine ²⁹ and access to disease- and vaccine-related information, leading to centralization of information and its dissemination by less rigorous means that promote ineffective therapies to the detriment of the vaccine ³⁰.

As with our study, other authors have suggested that the perceived risk of becoming infected, fear of the severity of the disease, a history of having been infected, or knowing an infected friend or relative were predictors of ITV ¹⁴. These findings are not limited to the COVID-19 vaccine, as similar results have been found for the acceptability of other vaccines ³¹. On the other hand, the prospect of not being able to work and the consequent economic insecurity and mental health problems could explain why people with depressive symptomatology and food insecurity are more likely to accept vaccination.

Most studies suggest that the influence of medical advice is the most important factor in accepting vaccination ¹⁴. In our study, although the advice of health workers was significant, WHO recommendations were more so. Despite the fact that the WHO disseminated discrepant information during the course of the pandemic ³², its status as the governing body on public health issues gives it credibility, so that reinforcing the importance of its messages would increase the ITV in our population. Similarly, as health workers are an important factor, the dissemination of standardized evidence-based messages should be considered, for example, during teleconsultation or with representative medical figures in regions with lower vaccine acceptance. In China, confidence in physicians as disseminators of vaccine-related information is 80% and in the United States it is 62%. On the other hand, in the United States, only 54% of the population trust the vaccine if it is approved by the Food and Drug Administration (FDA) ¹⁴. The fact that politicians’ recommendations are associated with a lower probability of ITV is worrisome, since they are frequently present in the media; however, it is understandable due to the lack of trust in them ³³. In the United States, political factors and the influence of former President Donald Trump affected vaccine acceptance, which should also be considered in our country ¹⁴.

Our study has some limitations. First, it is based on the responses of users of a social network to which not everyone has access. Nevertheless, it is a social network used by 94% of Peruvians, according to a survey conducted by Ipsos in 2020 ³⁴. Secondly, the variables included and their definition are subject to the pre-established definition of the matrix survey. Third, the data were obtained by self-reporting, so there may be an underreporting of information. Fourth, causality cannot be established between the variables evaluated due to the study design. Fifth, the measurements used to assess food and economic security have not been validated, but they provide relevant information for the study. Sixth, the findings could be biased due to the rejection rate of users in a Facebook survey, as well as due to the possibility of occurrence of voluntary response bias. Seventh, some of the associated factors found had a low measure of association, so their interpretation should be done cautiously, despite the statistical significance that the result may have. In spite of this, this is a study with a large sample size with national representativeness that can help to understand the research topic.

In conclusion, three out of four respondents reported having the ITV. Adequate communication strategies based on potentially modifiable factors could increase the possibility of acceptance of the COVID-19 vaccine in our country. Considering that the vaccination campaign will be a long-term task, continuous monitoring of vaccine acceptance is necessary to steer strategies in order to achieve the results proposed by the government.