Chlorine dioxide is a reactive synthetic gas that has been used in the paper industry, decontamination of public buildings, and water purification [5]. Its high reactivity explains its properties to eliminate microorganisms, however, this also determines the potential adverse effects [5]. Despite this, chlorine dioxide has been promoted as a cure for diseases such as malaria, HIV and cancer, among others [12]; it has also been proposed to prevent or treat COVID-19 [13]. However, there is no evidence on the efficacy of chlorine dioxide for such purposes, but there is evidence on its harmful effects, so institutions such as the Pan American Health Organization do not recommend its use [14].
Despite this, the present study found an approximate prevalence of 8% and 16% of chlorine dioxide consumption as prevention and treatment of COVID-19, respectively. We have not found studies published in scientific journals that have evaluated the prevalence of chlorine dioxide consumption in other countries. Although a previous study indicated that chlorine dioxide consumption in Peru is high, based on the number of related media articles and blog posts, a prevalence has not been specified [15]. This assumption is according to what we found, and it must be taken into account that the prevalence in our study could be underestimated, given that most of the population evaluated had characteristics in common, such as educational level, urban residence, etc., that make them less susceptible to the consumption of these substances, as has been previously reported [16].
In addition, the prevalence of chlorine dioxide consumption as a treatment is twice as high as its consumption as prevention. This could be explained by the fact that the diagnosis of COVID-19 can generate greater anxiety [17], and, therefore, desperation to act against the condition, leading to a greater susceptibility to consume this type of substance that is sold as a “miracle cure” for the disease [18]. Both as prevention or treatment of COVID-19, the consumption of this substance can have fatal consequences. On the one hand, those who use it for prevention may neglect adherence to truly effective preventive measures, such as social distancing or the use of masks. On the other hand, those who use it as treatment may tend to become complicated due to the delay in seeking health care. Taking into account that in both cases there may also be cases of intoxication, its consumption has implications not only for health but also for higher healthcare costs and a greater burden on health systems [19].
Factors associated with chlorine dioxide consumption
It was found that male participants consumed chlorine dioxide more frequently to prevent COVID-19. However, studies that evaluated the consumption of other substances (drugs) found no significant differences between the sexes [20]. Studies in other countries even found an association between female sex and the use of other substances (drugs, traditional medicine, vitamin C) for COVID-19 prevention [21]. This suggests the existence of factors specific to chlorine dioxide implicated in its higher consumption among the male population, such as the fact that the promoters of this substance were of the same sex, which may generate empathy in their peers [22]. Additionally, in Peru, according to the National Institute of Statistics and Informatics, men work more than women [23], a fact that could have led them to seek multiple prevention alternatives due to their greater exposure to COVID-19.
Likewise, it was found that being older than 30 years was associated with lower consumption of chlorine dioxide as prevention of COVID-19. In contrast to this, previous studies found heterogeneous results regarding the direction between the association of age and the use of unconventional medical practices [24]. However, for this study, the association found is possibly due to the fact that older people do not rely as much on chemical products and prefer more natural alternatives for this purpose [25]. Another factor that could explain our result is that the older population in Peru does not usually use social networks as an informative medium [26], and this was the main one where campaigns promoting the use of chlorine dioxide were promoted [6], so they may have had less exposure to news promoting its use. However, some studies suggest that fake news may have a greater reach in older populations [27]. For this reason, governments should warn against waves of misinformation from popular social networks and other media.
Among the family factors studied, it was reasonable to think that family members of health science students would have a lower prevalence of the use of substances without scientific evidence, such as chlorine dioxide. However, it was found that having a health sciences student increased the prevalence of consuming this substance to prevent COVID-19. This could be explained by the fact that at the family level the transmission of health information is based on experience, values, and customs [28], given that processes and ideologies that seek to protect health and manage disease triggers are developed in the domestic sphere [29]. In addition, the inexperience of the future physicians may have contributed to the use of chlorine dioxide by the other members. On the other hand, although in the bivariate analysis the presence of a health professional in the home was associated with a lower frequency of chlorine dioxide use, this was not the case when adjusted for the other variables. This could be due to the abundance of gray and scientific information without adequate quality [30], as well as a deficit in the use and applicability of the judicious use of evidence in health professionals in general [31].
Furthermore, it is noteworthy that having medical information (and not health professionals in general) as the main source of information about COVID-19 was associated with a lower prevalence of using chlorine dioxide as a preventive, which could be explained by the quality of information that a physician could provide about the false claims of chlorine dioxide. Also, the lack of an adequate source of information led many people to believe the sensationalist explanations of the product [32]. However, in the case of those who took chlorine dioxide as a treatment measure, the source of information was not associated, which leads us to believe that the fear of worsening or death from COVID-19 infection was greater and sufficient to influence their consumption, despite having received adequate information.
An interesting finding is that having comorbidities was associated with higher consumption of chlorine dioxide as COVID-19 prevention. These patients have a higher risk of mortality from COVID-19 [33], in addition to the fact that measures to treat their diseases may lead them to expose themselves more and decrease their preventive practices against COVID-19 [34]. Feeling more susceptible, the concern may lead them to seek complementary measures [35] such as evidence-free solutions to prevent the disease.
However, in the face of a disease detected as a threat, perceived susceptibility does not act the same as perceived severity [36]. In our study, people who considered COVID-19 a dangerous and fatal disease consumed less chlorine dioxide for prevention and treatment. This is similar to a study where it was found that being aware of COVID-19 severity may predict greater adherence to recommended prevention practices [37]. Both perceived severity and susceptibility depend on knowledge about the condition [36], so again, it is important to make efforts to combat infodemia and improve knowledge in the population so that people can improve their health practices and be able to recognize the ineffectiveness of practices without scientific evidence.
Concerning the use of other substances, it was found that the use of medicines and medicinal plants to prevent COVID-19 was associated with higher consumption of chlorine dioxide as a preventive measure. The use of medicinal plants [38] and self-medication are common practices in Peru, especially during the pandemic [20]. However, the fact that people consume one of these measures does not mean that they trust in its efficacy [39] leading them to seek more than one preventive measure such as medicines and to rely on pseudoscientific beliefs such as the consumption of chlorine dioxide [35]. This practice may result in the population having a false sense of security and relaxing preventive measures against COVID-19 [40].
It is crucial to highlight the importance of educating the population, which with an adequate source of information can learn about the damage that chlorine dioxide can have and its lack of benefits for COVID-19. As observed in our study, the belief that chlorine dioxide is not effective is associated with a lower consumption as prevention and treatment of COVID-19. The consumption of chlorine dioxide and its associated factors should be evaluated in other countries that have been under similar social and political influences as Peru. Information should be regulated by the media following the recommendations of institutions such as the Pan American Health Organization, which does not recommend chlorine dioxide, and not pseudoscientists.
Limitations and strengths
The present study has limitations that should be taken into account. First, the non-probabilistic sampling used makes it difficult to extrapolate the prevalences of chlorine dioxide consumption found, since, in the sample studied, the high percentage of women would decrease them, while the high percentage of young people would increase them. Secondly, the survey was distributed virtually and to acquaintances of the authors and collaborators of the study, a fact that could have led to the characteristics found in the sample studied (high percentage of young people, with higher education and from the urban sector). Thirdly, the sample of patients with a history of COVID-19 was considerably smaller than those without COVID-19, making the estimates for the first group more imprecise. However, a total of 3610 individuals were included, including respondents with and without a history of COVID-19, from the 24 departments of Peru. In addition, it should be taken into account that the prevalence of chlorine dioxide consumption was alarmingly high, so the study reveals a real problem in the country and to our knowledge, this is the first study that evaluates the factors associated with chlorine dioxide consumption in the general Peruvian population.