Dengue fever, chikungunya, and zika are highly prevalent arboviruses transmitted by hematophagous arthropods, with a widely neglected impact in developing countries. These diseases cause acute illness in diverse populations, as well as potential cardiovascular complications. A systematic review was carried out to investigate the burden of cardiac involvement related to these arboviruses. Multiple databases were searched for articles that investigated the association of cardiovascular diseases with arboviruses, published up to March 2022. Relevant articles were selected and rated by two independent reviewers. Proportion meta-analysis was applied to assess the frequency-weighted mean of the cardiovascular findings. A total of 42 articles were selected (n = 76,678 individuals), with 17 manuscripts on dengue and 6 manuscripts on chikungunya undergoing meta-analysis. The global pooled incidence of cardiac events in dengue fever using a meta-analysis was 27.21% (95% CI 20.21–34.83; I² = 94%). The higher incidence of dengue-related myocarditis was found in the population younger than 20 years old (33.85%; 95% CI 0.00–89.20; I² = 99%). Considering the studies on chikungunya (n = 372), the global pooled incidence of cardiac involvement using a meta-analysis was 32.81% (95% CI 09.58–61.49, I² = 96%). Two Zika studies were included that examined cases of infection by vertical transmission in Brazil, finding everything from structural changes to changes in heart rate variability that increase the risk of sudden death. In conclusion, cardiac involvement in arboviruses is not uncommon, especially in dengue fever.

SUMMARY Fever of undetermined origin (FUO) is a challenging entity with a striking presence in hospitals around the world and can be associated with a myriad of differential diagnoses. It is defined as axillary temperature ≥ 37.8 ° C on several occasions, lasting ≥ three weeks, in the absence of diagnosis after three days of hospital investigation or three outpatient visits. The main etiologies are: infectious, neoplastic, and rheumatic. The diagnosis is based on the detailed clinical history and physical examination of these patients, in order to direct the specific complementary tests to be performed in each case. Empirical therapy is not recommended (with few exceptions) in patients with prolonged fever, as it may disguise and delay the diagnosis and conduct to treat the specific etiology. The prognosis encompasses mortality of 12% - 35%, varying according to the underlying etiology. In this sense, the objective of this study is to review the main topics about fever of undetermined origin, bringing historical and scientific aspects, national and international.

OBJECTIVE: The aim of this study was to investigate whether the degree of urbanization influences the prevalence of chronic kidney disease Brazilian indigenous people.METHODS: This is a cross-sectional study conducted between 2016 and 2017 in northeastern Brazil and includes individuals aged between 30 and 70 years from two specific indigenous groups who volunteered to participate in the study: the Fulni-o people (lowest degree of urbanization) and the Truka group (greater degree of urbanization). Cultural and geographical parameters were used to characterize and measure the magnitude urbanization. We excluded individuals with known cardiovascular disease or renal failure who required hemodialysis. Chronic kidney disease was defined as a single measurement of an estimated glomerular filtration rate <60 mL/min/1.73 m2 using the Chronic Kidney Disease Epidemiology Collaboration creatinine equation.RESULTS: A total of 184 indigenous people from the Fulni-o group and 96 from the Truka group with a median age of 46 years (interquartile range: 15.2) were included. We found a chronic kidney disease rate of 4.3% in the total indigenous population, generally affecting an older population: 41.7% over 60 years old (p<0.001). The Truka people had a chronic kidney disease prevalence of 6.2%, with no differences in kidney dysfunction across age groups. The Fulni-o participants had a chronic kidney disease prevalence of 3.3%, with a higher proportion of kidney dysfunction in older participants (of the six Fulni-o indigenous people with chronic kidney disease, five were older).CONCLUSION: Our results suggest that a higher degree of urbanization seems to negatively influence the prevalence of chronic kidney disease Brazilian indigenous people.

Background: Chikungunya fever (CHIKF) is a serious public health problem with a high rate of infection and chronic disabling manifestations that has affected more than 2 million people worldwide since 2005. In spite of this, epidemiological data on vulnerable groups such as Indigenous people are scarce, making it difficult to implement public policies in order to prevent this disease and assist these populations. Objective: To describe the serological and epidemiological profile of chikungunya virus (CHIKV) in two Indigenous populations in Northeast Brazil, as well as in an urbanized control community, and to explore associations between CHIKV and anthropometric variables in these populations. Methodology/Principal findings: This is a cross-sectional ancillary study of the Project of Atherosclerosis among Indigenous Populations (PAI) that included people 30 to 70 years old, recruited from two Indigenous tribes (the less urbanized Fulni-ô and the more urbanized Truká people) and an urbanized non-Indigenous control group from the same area. Subjects underwent clinical evaluation and were tested for anti-CHIKV IgG by enzyme-linked immunosorbent assay. Serological profile was described according to ethnicity, sex, and age. The study population included 433 individuals distributed as follows: 109 (25·2%) Truká, 272 (62·8%) Fulni-ô, and 52 (12%) from the non-Indigenous urbanized control group. Overall prevalence of CHIKV IgG in the study sample was 49.9% (216; 95% CI: 45·1–54·7). When the sample was stratified, positive CHIKV IgG was distributed as follows: no individuals in the Truká group, 78·3% (213/272; 95% CI: 72·9–83·1) in the Fulni-ô group, and 5.8% (3/52; 95% CI: 1.21–16) in the control group. Conclusions/Significance: Positive tests for CHIKV showed a very high prevalence in a traditional Indigenous population, in contrast to the absence of anti-CHIKV serology in the Truká people, who are more urbanized with respect to physical landscape, socio-cultural, and historical aspects, as well as a low prevalence in the non-Indigenous control group, although all groups are located in the same area.

Arthropod-borne viral diseases are acute febrile illnesses, sometimes with chronic effects, that can be debilitating and even fatal worldwide, affecting particularly vulnerable populations. Indigenous communities face not only the burden of these acute febrile illnesses, but also the cardiovascular complications that are worsened by urbanization. A cross-sectional study was conducted in an Indigenous population in the Northeast Region of Brazil to explore the association between arboviral infections (dengue, chikungunya, and Zika) and cardiac biomarkers, including cardiotrophin 1, growth differentiation factor 15, lactate dehydrogenase B, fatty-acid-binding protein 3, myoglobin, N-terminal pro-B-type natriuretic peptide, cardiac troponin I, big endothelin 1, and creatine kinase-MB, along with clinical and anthropometric factors. The study included 174 individuals from the Fulni-ô community, with a median age of 47 years (interquartile range 39.0 to 56.0). High rates of previous exposure to dengue, chikungunya, and Zika were observed (92.5%, 78.2%, and 95.4% anti-IgG, respectively), while acute exposure (anti-IgM) remained low. The biomarkers were linked to age (especially in the elderly), obesity, chronic kidney disease, and previous or recent exposure to chikungunya. This study pioneers the use of Luminex xMAP technology to reveal the association between cardiac inflammatory biomarkers and exposure to classical arboviruses in an Indigenous population undergoing urbanization.