ABSTRACT.
Chagas disease (CD) is a parasitic disease endemic to continental Latin America that has globalized in recent years. The most relevant mechanisms of transmission of CD in non-endemic countries are transfusion with infected blood and mother-to-child transmission. There is limited information regarding practicing physicians’ knowledge of CD transmission, clinical presentation, and treatment in non-endemic countries, including Spain. Our objective was to analyze the level of knowledge about CD in family and community medicine residents and how it has evolved over the last 5 years. A cross-sectional study was performed in the framework of the training program for family and community medicine specialists in Alicante, Spain. Convenience sampling was used to enroll 214 fourth-year family and community medicine residents from 2016 to 2020. Participants completed the validated Chagas Level of Knowledge Scale questionnaire prior to attending the seminar “Health Care for the Immigrant Population.” The mean score on the scale was 7.1/10 points. Only 12 participants (5.6%) answered all questions correctly. Resident physicians who reported having received prior information on CD scored better than those who were not informed (mean, 7.2 versus 6.1 points). Participants from Latin America had scores similar to those of the rest of the participants. Over the 5-year study period, questionnaire scores tended to increase. Knowledge about CD among family and community medicine residents has improved in recent years, although it is still not optimal. Specific training on CD during specialized health care training is warranted.
INTRODUCTION
Chagas disease (CD) is a parasitic disease endemic to continental Latin America.1 In recent years, migration has globalized the relevance of this pathology, with rising diagnoses outside the endemic areas.1,2 The most relevant mechanisms of transmission of CD in non-endemic countries are transfusion with infected blood and congenital transmission from mother to child during pregnancy.1 Better knowledge of CD will allow early diagnosis, control of disease transmission, and adequate clinical management, including specific treatment when indicated.2 A recent study demonstrated the cost-effectiveness of implementing CD screening at the primary care level in non-endemic areas.3 Primary care constitutes the first point of care for patients in the health system and addresses health inequities in a multidisciplinary way. In that regard, migrants constitute one of the priority groups for targeted interventions.4 The most recent estimates show that more than 55,000 people were living with CD in Spain in 2018, 42% of whom were women of childbearing age. The overall underdiagnosis rate was around 71%, with an undertreatment rate of 82.5% in patients older than 14 years and about 60% in children.5
There is limited information regarding practicing physicians’ knowledge of CD transmission, clinical presentation, and treatment in Spain.6,7 Likewise, the level of knowledge about this disease among medical residents specializing in family and community medicine (F&CM) is unknown. This study aimed to assess the level of knowledge about CD in F&CM resident physicians and its evolution from 2016 to 2020.
MATERIALS AND METHODS
This descriptive cross-sectional study involved medical doctors during the fourth year of their training as F&CM doctors in Alicante. It was carried out with the collaboration of the Teaching Unit for Alicante Family and Community Medicine, the official institution in Alicante (a province within the Valencian Autonomous Community in Spain) supervising the training and learning skills of F&CM residents in all hospitals and primary health care centers in the province. The study was approved by the Research Project Evaluation Committee of Miguel Hernández University (Ref: DMC.JRR.01.16), within a project focusing on the level of knowledge about CD among health care professionals and students. All participants were informed of the study objectives before completing the knowledge assessment questionnaire. Participants’ eligibility criteria were as follows: The study included all fourth-year F&CM residents in Alicante, regardless of their nationality, who participated in the annual seminar titled “Health care for the Immigrant Population” as part of their training from 2016 to 2020. Thus, each resident could participate only once. They were invited to respond to the questionnaire at the beginning of the seminar. Anonymity and voluntary participation were guaranteed.
Before starting the face-to-face seminar, attendees completed the self-administered Chagas Level of Knowledge Scale (ChaLKS) for medical doctors (ChaLKS-Medical) questionnaire, a 10-item quiz assessing respondents’ knowledge about the epidemiology, transmission, clinical presentation, and treatment of CD. This instrument was validated in a prior study involving 283 medicine and pharmacy students and residents.8 Eight items have three possible answers: yes, no, and “I don’t know”; two items are multiple-choice. The “I don’t know” responses were coded as wrong answers. Responses to the multiple-choice questions were recorded in subsequent analyses as right or wrong. These questions addressed areas of basic knowledge on CD, considered essential for practicing F&CM in Spain.
Descriptive statistics were used to assess participants’ knowledge of CD. A difficulty index was determined for each question to explore gaps in CD knowledge: the lower the score, the more difficult the question. In addition, we used analysis of variance (ANOVA) to compare participants’ scores across the years after checking their normal distribution and χ2 to compare the frequency of wrong responses to each item according to self-reported previous training in CD and by the location of the university where participants had received their medical degree. The two-tailed significance level for all statistical tests was P < 0.05. All analyses were carried out on SPSS software version 23.0 (SPSS, Inc., Chicago, IL).
The Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) statement guidelines were used to improve the quality of the study (Supplemental material).
RESULTS
Sample and level of knowledge of CD.
Of the total number of F&CM residents from 2016 to 2020 (N = 262), 217 (82.8%) attended the seminar. A total of 214 physicians responded to the questionnaire (98.6% response rate). Most (200; 93.5%) reported having received prior information on CD before starting the training seminar. Thirty-three (15.4%) came from Latin American countries (Table 1).
Table 1.
Description of the sample of participants (N = 214)
| Variable | n | % |
|---|---|---|
| Year of the seminar | ||
| 2016 | 50 (50) | 23.4 |
| 2017 | 32 (44) | 15.0 |
| 2018 | 47 (51) | 22.0 |
| 2019 | 45 (52) | 21.0 |
| 2020 | 40 (65) | 18.7 |
| Location of university where participants earned their medical degree | ||
| Spain | 173 | 80.8 |
| Latin America | 33 | 15.4 |
| Eastern Europe | 6 | 2.8 |
| North Africa | 2 | 0.9 |
| Information received about Chagas disease before seminar | ||
| Yes | 200 | 93.5 |
| No | 14 | 6.5 |
| Setting where participants received prior information on Chagas | ||
| Academic preparation for residency | 156 | 72.9 |
| Medical degree | 58 | 27.1 |
| Knows someone with Chagas disease | ||
| Yes | 26 | 12.1 |
| No | 188 | 87.9 |
Values in parentheses represent total number of family and community medicine residents each year.
For 203 participants (94.9%), CD was a serious disease, and 64 (29.9%) thought that there were doctors sufficiently prepared to treat CD in Spain. Most (N = 207, 96.7%) maintained that travel carried a risk for contracting the disease, and 208 (97.2%) expressed their interest in knowing more about this entity.
Knowledge of CD.
The mean score on the scale among all participants was 7.1/10 points (95% CI: 6.9–7.3). In total, the knowledge scale registered 1,521 correct answers (71.1%) and 619 wrong ones (28.9%). Eleven doctors (5.1%) responded correctly on fewer than five items, 112 doctors (42.3%) got five to seven answers right, 79 (36.9%) responded correctly to eight or nine questions, and 12 (5.6%) answered all questions correctly. Table 2 shows the number of wrong answers for each question. The most frequent mistakes had to do with the drug of choice for treatment, transmission of the disease by blood transfusion or from mother to child, African (non) endemicity of the disease, and identification of the parasite that transmits the disease.
Table 2.
Wrong answers on Chagas knowledge scale and difficulty index of each question (N = 214)
| Knowledge item | Correct answer | Wrong answer | Difficulty index* | |
|---|---|---|---|---|
| n | % | |||
| Is CD endemic to the Americas? | Yes | 13 | 6.1 | 0.94 |
| Is CD endemic to Africa? | No | 75 | 35.0 | 0.65 |
| Is CD endemic to Europe? | No | 0 | 0.0 | 1.00 |
| Can CD be transmitted from mother to child? | Yes | 94 | 43.9 | 0.56 |
| Can CD be transmitted through blood transfusions? | Yes | 98 | 45.8 | 0.54 |
| Can CD be transmitted by kissing bugs? | Yes | 75 | 35.0 | 0.65 |
| Can CD affect the heart? | Yes | 9 | 4.2 | 0.96 |
| Can CD affect the stomach and bowels? | Yes | 24 | 11.2 | 0.89 |
| Is CD diagnosed via serology? | Yes | 41 | 19.2 | 0.81 |
| What drug is used to treat CD? | Benznidazole or nifurtimox | 190 | 88.8 | 0.11 |
CD = Chagas disease.
Difficulty index (0 to 1) calculated during the validation study of the knowledge scale7; lower values represent more difficulty.
Evolution of the level of knowledge of CD.
Throughout the 5-year study period, the frequency of correct answers gradually increased (F = 2.9; P = 0.023; Table 3). Globally, the score increased +0.8 (95% CI: 0.4–1.4) points. Table 4 shows this evolution for each of the 10 items evaluated. In general, all of the questions followed a similar pattern of increased knowledge. The exception was the item on African (non) endemicity of CD, which showed an uneven frequency of right answers, with similar results in 2016 and 2020.
Table 3.
Scores on the knowledge scale, 2016 to 2020 (N = 214)
| Year | n | Mean score | SD | 95% CI | |
|---|---|---|---|---|---|
| 2016 | 50 | 6.8 | 1.7 | 6.4 | 7.3 |
| 2017 | 32 | 6.6 | 1.8 | 5.9 | 7.3 |
| 2018 | 47 | 7.0 | 1.4 | 6.6 | 7.4 |
| 2019 | 45 | 7.5 | 1.1 | 7.2 | 7.8 |
| 2020 | 40 | 7.6 | 1.6 | 7.0 | 8.1 |
Table 4.
Frequency of wrong answers to each question, 2016 to 2020 (N = 214)
| 2016 | 2017 | 2018 | 2019 | 2020 | P value* | ||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| Item | n | % | n | % | n | % | n | % | n | % | |
| Is CD endemic to the Americas? | 2 | 4.0 | 5 | 15.6 | 2 | 4.3 | 2 | 4.4 | 2 | 5.0 | 0.20 |
| Is CD endemic to Africa? | 14 | 28.0 | 20 | 62.5 | 8 | 17.0 | 20 | 44.4 | 13 | 32.5 | 0.001 |
| Is CD endemic to Europe? | 0 | 0.0 | 0 | 0.0 | 0 | 0.0 | 0 | 0.0 | 0 | 0.0 | 1.00 |
| Can CD be transmitted from mother to child? | 27 | 54.0 | 14 | 43.8 | 22 | 46.8 | 17 | 37.8 | 14 | 35.0 | 0.38 |
| Can CD be transmitted through blood transfusions? | 21 | 42.0 | 14 | 43.8 | 27 | 57.4 | 19 | 42.2 | 17 | 42.5 | 0.51 |
| Can CD be transmitted by kissing bugs? | 20 | 40.0 | 10 | 31.2 | 24 | 51.1 | 6 | 13.3 | 15 | 37.5 | 0.004 |
| Can CD affect the heart? | 3 | 6.0 | 4 | 12.5 | 1 | 2.1 | 1 | 2.2 | 0 | 0.0 | 0.73 |
| Can CD affect the stomach and bowels? | 9 | 18.0 | 5 | 15.6 | 4 | 8.5 | 4 | 8.9 | 2 | 5.0 | 0.28 |
| Is CD diagnosed via serology? | 15 | 30.0 | 7 | 21.9 | 8 | 17.0 | 6 | 13.3 | 5 | 12.5 | 0.18 |
| What drug is used to treat CD? | 47 | 94.0 | 30 | 93.8 | 45 | 95.7 | 38 | 84.4 | 30 | 75.0 | 0.012 |
CD = Chagas disease.
P value was obtained by χ2.
Differences in knowledge of CD.
Resident physicians who reported having previously received information on CD did better on the knowledge questionnaire (mean score, 7.2 points, SD 1.5 points) than those who did not (6.1 points, SD 2.0 points; P = 0.009). The score was similar between participants who studied medicine in Latin America and those who studied medicine in other locations. No differences were found in the number of correct answers between those who studied medicine in Latin America and those who studied in Europe (7.2 points, SD 1.6 points versus 6.84 points, SD 1.2 points; P = 0.11). However, none of the doctors from Latin America made a mistake on the item regarding the endemicity of CD to the Americas or the fact that cardiac disease is among its most important manifestations. Instead, the physicians who studied medicine in Latin America tended to make mistakes on items about digestive involvement, vertical transmission, and the African (non) endemicity of the disease.
DISCUSSION
Our study shows that the level of knowledge about CD among doctors training in F&CM has tended to improve in recent years. The number of right answers about the appropriate drug treatment of CD has increased, although the proportion of incorrect responses is still persistently high. Despite the increase in knowledge in this group, we suggest that knowledge about the transmission routes of the disease, which is key for preventing autochthonous and congenital infections as well as controlling blood donations, remains insufficient.
There is a scarcity of studies about CD awareness among primary care physicians or family doctors in non-endemic countries, and our results are consistent with them; there is still room for improvement.9–11 To our knowledge, there have been no published studies about its evolution over time.
The previous validation study (ChaLKS) identified essential knowledge about CD that F&CM physicians should possess in order to properly identify and manage this disease.8 Our results, together with the documented increase in imported cases of CD in recent years,12 suggest that this area of knowledge warrants dedicated focus during specialty training. Prior training in CD or contact with people with CD predicts better knowledge of the disease, which suggests that regulated training during undergraduate studies can improve knowledge levels.13 This need for enhanced training acquires special relevance in the context of the globalization of other infectious diseases apart from CD and the need to adapt to this reality.14
In Spain, the diagnosis and management of this pathology has been carried out mainly in the hospital environment, with these tasks falling to the tropical medicine/international health units,15,16 unlike in endemic countries, where CD is managed in primary care.17,18 However, the importance of primary care in CD is gaining ground in our setting, with family physicians acquiring experience in managing the disease and the side effects of its drug treatment.19,20 The efficiency of screening for CD at the primary care level has been demonstrated, and more family physicians are receiving training.3,21 Therefore, this imported pathology, which has often become a chronic disease that needs to be periodically monitored in our patients, could be managed in primary care. Moreover, providing comprehensive care for patients with CD in this setting could help eliminate barriers related to access to the health care system and adherence to follow-up.2
This study highlights the relevance of training F&CM residents in this pathology, as primary health care doctors, either alone or in collaboration with hospital professionals, can play a fundamental role in identifying people at risk, diagnosing cases, and managing patients with CD clinically and pharmacologically. Furthermore, F&CM teams perform community health activities that are vital for the population susceptible to CD.
Turning to specific questions on the ChaLKS questionnaire, our results show confusion about the African endemicity of the disease, an aspect that has not improved over time among future family doctors. This may be due to the similarity between the microorganisms that cause CD (American trypanosomiasis) and sleeping sickness (African trypanosomiasis), both flagellate protozoa of the genus Trypanosoma. Despite the obvious differences between these entities in terms of insect vector, transmission, pathogenesis, clinical presentation, and treatment, there is persistent confusion among students and young professionals in medicine and pharmacy during teaching activities.11,13 These aspects further underline the need to improve training on this and other emerging diseases in future health care professionals.
One positive finding was that practically all participants wanted more information about CD, which suggests that many would be interested in attending workshops or conferences on this disease. That said, the responsibility for training residents in imported and emerging diseases should not reside with new physicians themselves.
This study is limited by its performance in a single province of Spain, meaning that the results may not be generalizable to other regions or countries. In addition, participants’ knowledge about CD was not assessed after the seminar to verify the effectiveness of the training. Finally, the sample was composed exclusively of F&CM residents in the province of Alicante. Extrapolation of the results to other contexts and professional cadres should be done with caution.
Future research on this topic, including the evaluation of whether/how teaching plans improve future health care professionals’ knowledge on CD in both endemic and non-endemic areas, is desirable.
In conclusion, although knowledge about CD among F&CM residents seemed to improve in the last 5 years, it is not yet sufficient to prepare them for professional practice with patients affected by this entity. There is a need for training on CD in future F&CM physicians during their residency, oriented toward rapid and adequate diagnosis of the disease and the correct treatment of patients.
Supplemental Materials
ACKNOWLEDGMENTS
We thank all participants of this study. We acknowledge Meggan Harris for proofreading of the manuscript.
Note: Supplemental materials appear at www.ajtmh.org.
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