ABSTRACT Objective: This study aimed to present a temporal and spatial analysis of the 2018 measles outbreak in Brazil, particularly in the metropolitan city of Manaus in the Amazon region, and further introduce a new tool for spatial analysis. Methods: We analyzed the geographical data of the residences of over 7,000 individuals with measles in Manaus during 2018 and 2019. Spatial and temporal analyses were conducted to characterize various aspects of the outbreak, including the onset and prevalence of symptoms, demographics, and vaccination status. A visualization tool was also constructed to display the geographical and temporal distribution of the reported measles cases. Results: Approximately 95% of the included participants had not received vaccination within the past decade. Heterogeneity was observed across all facets of the outbreak, including variations in the incubation period and symptom presentation. Age distribution exhibited two peaks, occurring at one year and 18 years of age, and the potential implications of this distribution on predictive analysis were discussed. Additionally, spatial analysis revealed that areas with the highest case densities tended to have the lowest standard of living. Conclusion: Understanding the spatial and temporal spread of measles outbreaks provides insights for decision-making regarding measures to mitigate future epidemics. Objective 201 Brazil region Methods 7000 7 000 7,00 2019 symptoms demographics status cases Results 95 decade presentation peaks 1 age discussed Additionally living Conclusion decisionmaking decision making epidemics 20 700 00 7,0 9 2 70 0 7,

ABSTRACT The group-specific antigen (gag) plays a crucial role in the assembly, release, and maturation of HIV. This study aimed to analyze the partial sequence of the HIV gag gene to classify HIV subtypes, identify recombination sites, and detect protease inhibitor (PI) resistance-associated mutations (RAMs). The cohort included 100 people living with HIV (PLH) who had experienced antiretroviral treatment failure with reverse transcriptase/protease inhibitors. Proviral HIV-DNA was successfully sequenced in 96 out of 100 samples for gag regions, specifically matrix (p17) and capsid (p24). Moreover, from these 96 sequences, 82 (85.42%) were classified as subtype B, six (6.25%) as subtype F1, one (1.04%) as subtype C, and seven (7.29%) exhibited a mosaic pattern between subtypes B and F1 (B/F1), with breakpoints at p24 protein. Insertions and deletions of amino acid at p17 were observed in 51 samples (53.13%). The prevalence of PI RAM in the partial gag gene was observed in 78 out of 96 PLH (81.25%). Among these cases, the most common mutations were R76K (53.13%), Y79F (31.25%), and H219Q (14.58%) at non-cleavage sites, as well as V128I (10.42%) and Y132F (11.46%) at cleavage sites. While B/F1 recombination was identified in the p24, the p17 coding region showed higher diversity, where insertions, deletions, and PI RAM, were observed at high prevalence. In PLH with virological failure, the analysis of the partial gag gene could contribute to more accurate predictions in genotypic resistance to PIs. This can aid guide more effective HIV treatment strategies. groupspecific group specific (gag assembly release sites (PI resistanceassociated associated RAMs. RAMs . (RAMs) 10 (PLH transcriptaseprotease transcriptase inhibitors HIVDNA DNA 9 regions p (p17 p24. (p24) Moreover sequences 8 85.42% 8542 85 42 (85.42% 6.25% 625 6 25 (6.25% F 1.04% 104 1 04 (1.04% C 7.29% 729 7 29 (7.29% B/F1, BF1 BF , (B/F1) p2 protein p1 5 53.13%. 5313 53.13% 53 13 (53.13%) 81.25%. 8125 81.25% 81 (81.25%) cases RK R K 53.13%, YF Y 31.25%, 3125 31.25% 31 (31.25%) HQ H Q 14.58% 1458 14 58 (14.58% noncleavage non VI V I 10.42% 1042 (10.42% 11.46% 1146 11 46 (11.46% B/F diversity insertions PIs strategies (RAMs (p1 (p24 85.42 854 4 (85.42 6.25 62 2 (6.25 1.04 0 (1.04 7.29 72 (7.29 (B/F1 531 53.13 (53.13% 812 81.25 (81.25% 312 31.25 3 (31.25% 14.58 145 (14.58 10.42 (10.42 11.46 114 (11.46 (p (p2 85.4 (85.4 6.2 (6.2 1.0 (1.0 7.2 (7.2 (B/F 53.1 (53.13 81.2 (81.25 31.2 (31.25 14.5 (14.5 10.4 (10.4 11.4 (11.4 85. (85. 6. (6. 1. (1. 7. (7. 53. (53.1 81. (81.2 31. (31.2 14. (14. 10. (10. 11. (11. (85 (6 (1 (7 (53. (81. (31. (14 (10 (11 (8 ( (53 (81 (31 (5 (3

ABSTRACT This study aimed to provide further insight into the evolutionary dynamics of SARS-CoV-2 by analyzing the case of a 40-year-old man who had previously undergone autologous hematopoietic stem cell transplantation due to a diffuse large B-cell lymphoma. He developed a persistent SARS-CoV-2 infection lasting at least 218 days and did not manifest a humoral immune response to the virus during this follow-up period. Whole-genome sequencing and viral cultures confirmed a persistent infection with a replication-positive virus that had undergone genetic variation for at least 196 days after symptom onset. SARSCoV2 SARSCoV SARS CoV 2 SARS-CoV- 40yearold yearold 40 year old Bcell B lymphoma 21 followup follow up period Wholegenome Whole genome replicationpositive replication positive 19 onset SARS-CoV 4 1

ABSTRACT In Brazil, Dengue, Zika and Chikungunya viruses constitute a major threat to the public health system. Simultaneous circulation of these arboviruses occurs in many regions of the world due to the expansion of transmission vectors. The infection by these arboviruses triggers similar symptoms during their acute phase. However, in some cases, severe symptoms may occur, leading to different types of disabilities and even death. In this context, considering the similarity of the symptoms, the problems caused by the infection of these arboviruses, and the increasing risk of coinfection in humans, the differential diagnosis of these infections is essential for clinical management and epidemiological investigation. Thus, this study aimed to identify, through diagnosis via Quantitative Polymerase Chain Reaction with Reverse Transcription, arbovirus coinfection in patients from the Tocantins state (Northern Brazil). A total of 495 samples were analyzed, three from which were determined to be a coinfection of Dengue and Chikungunya viruses. The data obtained here indicate the co-circulation and coinfection by Dengue and Chikungunya viruses in the Tocantins state. These results highlight the importance of monitoring the circulation of these arboviruses for the development of health actions that aim their prevention and combat, as well as their clinical and therapeutic management. Brazil system vectors phase However cases occur death context humans investigation Thus identify Transcription Northern Brazil. . Brazil) 49 analyzed cocirculation co combat 4

ABSTRACT Vaccination coverage has been dropping in Brazil and other countries. In addition, immune responses after vaccination may not be homogeneous, varying according to sociodemographic and clinical factors. Understanding the determinants of incomplete vaccination and negative antibody test results may contribute to the development of strategies to improve vaccination effectiveness. In this study, we aimed to investigate the frequency of vaccine adherence, factors associated with incomplete vaccination for measles, mumps, rubella (MMR) and hepatitis A, and factors associated with the seronegative test results for measles, mumps and hepatitis A at 2 years of age. This was a population-based cohort that addressed health conditions and mother/infant nutrition in Cruzeiro do Sul city, Brazil. Vaccination data were obtained from official certificates of immunization. The children underwent blood collection at the two-year-old follow-up visit; the samples were analyzed using commercially available kits to measure seropositivity for measles, mumps, and hepatitis A. We used modified Poisson regression models adjusted for covariates to identify factors associated with incomplete vaccination and negative serology after vaccination. Out of the 825 children included in the study, adherence to the vaccine was 90.6% for MMR, 76.7% for the MMRV (MMR + varicella), and 74.9% for the hepatitis A vaccine. For MMR, after the adjustment for covariates, factors associated with incomplete vaccination included: white-skinned mother; paid maternity leave; raising more than one child; lower number of antenatal consultations; and attending childcare. For hepatitis A, the factors included: white-skinned mother and not having a cohabiting partner. The factors with statistically significant association with a negative antibody test result included: receiving Bolsa Familia allowance for measles and mumps; incomplete vaccination for measles; and vitamin A deficiency for mumps. Strategies to improve the efficiency of vaccine programs are urgently needed. These include improvements in communication about vaccine safety and efficacy, and amplification of access to primary care facilities, prioritizing children exposed to the sociodemographic factors identified in this study. Additionally, sociodemographic factors and vitamin A deficiency may impact the immune responses to vaccines, leading to an increased risk of potentially severe and preventable diseases. countries addition homogeneous effectiveness study MMR age populationbased population based motherinfant infant city immunization twoyearold two year old followup follow up visit 82 906 90 6 90.6 767 76 7 76.7 varicella, varicella , varicella) 749 74 9 74.9 whiteskinned white skinned leave child consultations childcare partner needed efficacy facilities Additionally vaccines diseases 8 90. 76. 74.

ABSTRACT Numerous tests employed to predict cardiac and functional status are expensive and not widely accessible for a considerable number of patients, particularly those diagnosed with Chagas disease (CD) residing in remote and endemic regions. To date, there is no knowledge of studies that have validated instruments that address functionality in an expanded way, including the biopsychosocial factors in patients with CD. This study aims to evaluate the psychometric properties of the World Health Organization Disability Assessment Schedule (WHODAS 2.0), in its 12-item shortened version (WHODAS-12) when applied to patients with CD. This is a cross-sectional study of a prospective cohort that follows individuals with CD (SaMi-Trop). Data collection took place between October 2019 and March 2020. In the interviews, sociodemographic information, life habits, clinical information, and indicators of disability measured by WHODAS-12 were collected. Descriptive analysis, internal consistency and construct validity of the instrument were performed. A total of 628 patients with CD were interviewed, most were women (69.5%), their mean age was of 57 years, and most declared an average self-perception of health (43.4%). The 12 items of WHODAS-12 were distributed into three factors, which together account for 61% of the variance. The Kaiser–Meyer–Olkin (KMO) index was 0.90, indicating adequacy of the sample for factor analysis. The internal consistency of the global scale showed alpha = 0.87. The percentage of incapacity was 16.05%, indicating mild incapacity for the evaluated patients. WHODAS-12 is a valid and reliable measure to assess the disability of the Brazilian population with CD. (CD regions date way WHODAS 2.0, 20 2.0 , 2 0 2.0) 12item item WHODAS12 (WHODAS-12 crosssectional cross sectional SaMiTrop. SaMiTrop SaMi Trop . (SaMi-Trop) 201 2020 interviews information habits WHODAS-1 collected analysis performed 62 interviewed 69.5%, 695 69.5% 69 5 (69.5%) years selfperception self perception 43.4%. 434 43.4% 43 4 (43.4%) 1 61 variance KaiserMeyerOlkin Kaiser Meyer Olkin KMO (KMO 090 90 0.90 087 87 0.87 1605 16 05 16.05% 2. WHODAS1 (WHODAS-1 (SaMi-Trop 202 WHODAS- 6 69.5 (69.5% 43.4 (43.4% 09 9 0.9 08 8 0.8 160 16.05 (WHODAS- 69. (69.5 43. (43.4 0. 16.0 (69. (43. 16. (69 (43 (6 (4 (

ABSTRACT Chagas disease (CD) is a neglected disease caused by the protozoan Trypanosoma cruzi. It has high morbidity and mortality rates and mainly affects socially vulnerable populations. This is a cross-sectional study, with retrospective and prospective data collection. Using questionnaires applied to environmental surveillance coordinators, we characterized the status of CD surveillance activities in municipalities endemic for the disease in Northern Minas Gerais State (MG) and Jequitinhonha Valley (Vale do Jequitinhonha). Moreover, we spatialized the vulnerability index for chronic CD in the study area. The population consisted of 22 environmental surveillance coordinators, active in 2020, from Northern MG and Jequitinhonha Valley, 21 municipalities included in the SaMi-Trop research project, and Montes Claros municipality. After applying the questionnaires to the coordinators, a descriptive analysis of the variables was performed. To characterize the active municipalities, the explanatory variables collected in the questionnaire were compared with the dichotomous variable. Bivariate descriptive analysis was performed. Finally, geoprocessing techniques were used to spatialize the data and prepare maps. Regarding the team of endemic combat agents (ECA), 90.9% reported the lack of a specific team for CD vector control actions. Of the 22 municipalities participating in this study, nine were active (41.1%). Only 25% (n=2) of active municipalities (9% of the municipalities studied) met the target of visiting 50% of households per year. Finally, 81.1% of the coordinators stated that in their municipality, they developed actions linked to primary health care (PHC). The implementation of CD surveillance activities weakened in the endemic region. Few municipalities have a surveillance team, with low regularity of active surveillance and noncompliance with the program’s goal. The results suggest insufficient recording of activities in the information system, considering that there are municipalities that report performing the activities, but no production record was observed in the system. (CD cruzi populations crosssectional cross sectional collection (MG Vale Jequitinhonha. . Jequitinhonha) Moreover area 2 2020 SaMiTrop SaMi Trop project municipality performed variable Finally maps ECA, ECA , (ECA) 909 90 9 90.9 41.1%. 411 41.1% 41 1 (41.1%) 25 n=2 n2 n (n=2 9% (9 studied 50 year 811 81 81.1 PHC. PHC (PHC) region programs program s goal system 202 (ECA 90. 41.1 4 (41.1% n= (n= ( 5 8 81. (PHC 20 41. (41.1 (n (41. (41 (4

ABSTRACT Background: Chagas disease (ChD) is a neglected tropical disease that is caused by the protozoan parasite Trypanosoma cruzi and can negatively impact quality of life (QoL). This study aimed to assess and compare QoL between individuals with and without ChD. Methods: This cross-sectional study was performed within a concurrent cohort study (REDS). The participants were derived from two blood donation centers: São Paulo capital and Montes Claros, Minas Gerais, Brazil. Participants with ChD were identified in blood donations by serological diagnosis between 2008 and 2010, and those without ChD were donors with negative serology identified during the same period. QoL was assessed using the World Health Organization Quality of Life-BREF questionnaire. Logistic regression was used to compare sociodemographic and clinical characteristics between the groups, and mean, standard deviation, and beta regression were used to compare QoL. Results: In total, 611 individuals participated in the study (328 with ChD and 283 without ChD). Participants with ChD had lower QoL in the physical (p=0.02) and psychological (p<0.01) domains than did individuals without CD. Conclusions: Individuals with ChD had worse QoL perceptions. These results provide a comprehensive understanding of the impact of ChD on individuals' QoL, while also highlighting potential opportunities for improving the care and treatment of those affected. Background (ChD . (QoL) Methods crosssectional cross sectional REDS. REDS (REDS) centers Claros Gerais Brazil 200 2010 period LifeBREF Life BREF questionnaire groups mean deviation Results total 61 328 (32 28 ChD) p=0.02 p002 p 0 02 (p=0.02 p<0.01 p001 01 (p<0.01 CD Conclusions perceptions affected (QoL (REDS 20 201 6 32 (3 2 p=0.0 p00 (p=0.0 p<0.0 (p<0.0 3 ( p=0. p0 (p=0. p<0. (p<0. p=0 (p=0 p<0 (p<0 p= (p= p< (p< (p

ABSTRACT Among individuals coinfected with HCV and HIV, studies of mortality from non-hepatic causes have shown inconsistent results. The aim of this study was to investigate the contribution of HCV and HIV co-infection to mortality from hepatic and non-hepatic causes in Brazil. This retrospective cohort study included blood donors from Fundação Pró-Sangue de São Paulo (FPS) who were followed from 1994 to 2016 to compare mortality and its causes between HIV-HCV coinfected individuals versus those seronegative for all tested infections. Records from the FPS database and the Mortality Information System were linked through a probabilistic record Relationship (RL). The Hazard Ratio (HR) was estimated using Cox multiple regression models. HCV-HIV coinfected individuals compared to seronegative individuals had a higher risk of death from all causes (HR = 14.54), non-liver neoplasms (HR = 2.55), infections (HR = 10.37) and liver disease (HR = 7.0). In addition, HCV mono-infected individuals compared to seronegative individuals had a higher risk of death from all causes (HR = 2.23), liver cancer (HR = 32.21), liver disease (HR = 14.92), infection (HR = 3.22), and trauma (HR = 1.68). Individuals coinfected with HCV and HIV have increased overall mortality and death due to infections, liver diseases and non-liver neoplasms as compared to those uninfected with HCV and HIV. nonhepatic non results coinfection co Brazil PróSangue Pró Sangue (FPS 199 201 HIVHCV RL. RL . (RL) HR models HCVHIV 14.54, 1454 14.54 , 14 54 14.54) nonliver 2.55, 255 2.55 2 55 2.55) 10.37 1037 10 37 7.0. 70 7.0 7 0 7.0) addition monoinfected mono infected 2.23, 223 2.23 23 2.23) 32.21, 3221 32.21 32 21 32.21) 14.92, 1492 14.92 92 14.92) 3.22, 322 3.22 3 22 3.22) 1.68. 168 1.68 1 68 1.68) 19 20 (RL 145 14.5 5 25 2.5 10.3 103 7. 2.2 32.2 149 14.9 9 3.2 16 1.6 6 14. 2. 10. 32. 3. 1.

Abstract Introduction Leg ulcers (LUs) are relatively common in patients with sickle cell anemia (SCA). The role of inflammation and nitric oxide (NO) pathways in the pathophysiology of the LU is not understood. Objective The aim of this study was to verify the association between inflammatory molecules and nitric oxide metabolites (NOx) and the occurrence of the LU in patients with SCA. Method It was a cross-sectional study on adult participants with SCA followed at Fundação Hemominas, a public blood center in Brazil. Eligible participants were recruited and included in one of two groups: Group 1, comprised of cases with SCA (Hb SS) and at least one LU at the time of inclusion in the study and Group 2, comprised of controls with SCA without a history of LU, matched by sex and age to cases. Participants were interviewed to obtain sociodemographic data and blood samples were collected. Clinical and laboratory data were abstracted from medical records. Nitric oxide metabolites (NOx) and inflammatory molecules were quantified using an immunoassay and Multiplex xMAP® technology, respectively. Eighty-seven individuals were included, ranging in age from 17 to 61 years (mean 40 ± 10.7 years); 30 had LU and 57 were controls without LU. Results Participants with LU had significantly higher levels of interleukin 8 (IL-8), IL-10, IL-15, NOx and platelet and white blood cell (WBC) counts, when compared to those without LU. Participants with LU had a significantly higher risk of having a history of osteomyelitis and a higher use of antiseptic soap in bathing, when compared to those without LU. Conclusion In conclusion, our results showed that NOx, inflammatory molecules and hematological features were associated with LU in Brazilian adults with SCA.

Abstract Objectives: To determine the incidence and risk of adverse obstetric and neonatal outcomes according to SARS-CoV-2 infection severity in pregnant women. Method: Open prospective study of pregnant women tested for SARS-CoV-2 by serological and molecular assays during pregnancy or delivery in two hospitals in Sao Paulo, Brazil from April 12, 2020, to February 28, 2021. Five groups were considered for analysis: C0, negative COVID-19 results and no COVID-19 symptoms; C1, positive COVID-19 results, and no symptoms; C2, positive COVID-19 results with mild symptoms; C3, positive COVID-19 results with moderate symptoms; and C4, positive COVID-19 results with severe symptoms. The association between obstetric and neonatal outcomes and COVID-19 severity was determined using multivariate analysis. Results: 734 eligible pregnant women were enrolled as follows: C0 (n = 357), C1 (n = 127), C2 (n = 174), C3 (n = 37), and C4 (n = 39). The following pregnancy and neonatal outcomes were associated with severe COVID-19: oligohydramnios (adjusted Odds Ratio [aOR] = 6.18; 95% CI 1.87‒20.39), fetal distress (aOR = 4.01; 95% Confidence Interval [CI] 1.84‒8.75), preterm birth (aOR = 5.51; 95% CI 1.47‒20.61), longer hospital stay (aOR = 1.66; 95% CI 1.36‒2.02), and admission to the neonatal intensive care unit (aOR = 19.36; 95% CI, 5.86‒63.99). All maternal (n = 6, 15.4%, p < 0.001) and neonatal (n = 5, 12.5%, p < 0.001) deaths and most fetal deaths (n = 4, 9.8%, p < 0.001) occurred in C4 group. Moderate COVID-19 was associated with oligohydramnios (aOR = 6.23; 95% CI 1.93‒20.13) and preterm birth (aOR = 3.60; 95% CI 1.45‒9.27). Mild COVID-19 was associated with oligohydramnios (aOR=3.77; 95% CI 1.56‒9.07). Conclusion: Adverse pregnancy and neonatal outcomes were associated with maternal symptomatic COVID-19 status, and risk increased with disease severity. HIGHLIGHTS COVID-19 increases the rates of adverse pregnancy and neonatal outcomes. Serious cases are associated with oligohydramnios, fetal distress, prematurity, neonatal ICU admission, maternal and neonatal deaths. The maternal clinical status dictates obstetric and neonatal outcomes.

Abstract Objectives: The aim of the present study was to evaluate if neutralizing antibody responses induced by infection with the SARS-CoV-2 strain that was dominant at the beginning of the pandemic or by the Gamma variant was effective against the Omicron variant. Methods: Convalescent sera from 109 individuals, never exposed to a SARS-CoV-2 vaccine, who had mild or moderate symptoms not requiring hospitalization following either a documented SARS-CoV-2 ancestral strain infection or a Gamma variant infection, were assayed for in vitro neutralizing antibody activity against their original strains and the Omicron variant. Results: Following an infection with the ancestral strain, 56 (93.3%), 45 (77.6%) and 1 (1.7%) serum sample were positive for neutralizing antibodies against the ancestral, Gamma variant, and Omicron variant, respectively. After infection with the Gamma variant, 43 (87.8%) and 2 (4.1%) sera were positive for neutralizing antibodies against the Gamma and Omicron variants, respectively. Conclusions: Neutralizing antibodies generated following mild or moderate infection with the SARS-CoV-2 ancestral strain or the Gamma variant are not protective against the Omicron variant. HIGHLIGHTS Individuals previously infected with SARS-CoV-2 ancestral strain do not develop neutralizing antibodies against the Omicron variant. Omicron variant escapes immune response after SARS CoV-2 previous infection with the SARS CoV-2 Gamma variant. Individuals previously infected with SARS-CoV-2 ancestral strain or with SARS-CoV-2 Gamma variant will likely have little protection if subsequently exposed to the Omicron variant.

ABSTRACT In 2022, an outbreak of monkeypox is being reported in non-endemic areas, with unusual clinical manifestations. The detailed clinical description of the first patient that received the diagnosis of monkeypox in Brazil is reported here, whose clinical manifestations can easily lead to misdiagnosis of sexually transmitted infections. A 41 years old male presented to an emergency room with a vesicular rash with eight days of evolution. He had traveled to Portugal and Spain and reported non-penetrative sexual involvement with three different male individuals. On the third day of symptoms, he sought medical care and received empirical treatment directed to sexually transmitted infections. As the symptoms did not improve, he sought medical attention at an infectious disease referral center presenting, on admission, an ulcerated penile lesion with central necrotic crusts, a disseminated pleomorphic skin rash and an oropharyngeal ulcer. The monkeypox diagnosis was suspected due to the characteristics of the lesions and the history of intimate contact with casual partners, and it was later confirmed by sequencing the almost complete monkeypox genome. The patient was hospitalized for pain control, which required opiate administration. He developed a secondary bacterial infection on the penile lesions, which were treated with oral antibiotics. He was discharged after 14 days, with lesions in process of re-epithelialization. Given the current outbreak, we must consider the possibility of monkeypox in patients with suggestive lesions, anywhere on the body (including the genitals), added to an epidemiological link or history of intimate contact with strangers or casual partners.

ABSTRACT Background: Despite their worldwide occurrence, the distribution and role of insect-specific flaviviruses (ISFs) remain unclear. Methods: We evaluated the presence of ISFs in mosquitoes collected in São Paulo, Brazil, using reverse transcription and semi-nested polymerase chain reaction (PCR). Some of the positive samples were subjected to nanopore sequencing. Results: Twelve mosquito pools (2.8%) tested positive for flavivirus infection. Nanopore sequencing was successfully performed on six samples. Phylogenetic analysis grouped these sequences into genotype 2 of Culex flavivirus (CxFV). Conclusions: The identification of CxFV genotype 2 at new locations in São Paulo highlights the importance of understanding the role of ISFs in mosquito vector competence.

ABSTRACT COVID-19 disease is spread worldwide and diagnostic techniques have been studied in order to contain the pandemic. Immunochromatographic (IC) assays are feasible and a low-cost alternative especially in low and middle-income countries, which lack structure to perform certain diagnostic techniques. Here we evaluate the sensitivity and specificity of eleven different IC tests in 145 serum samples from confirmed cases of COVID-19 using RT-PCR and 100 negative serum samples from blood donors collected in February 2019. We also evaluated the cross-reactivity with dengue using 20 serum samples from patients with confirmed diagnosis for dengue collected in early 2019 through four different tests. We found high sensitivity (92%), specificity (100%) and an almost perfect agreement (Kappa 0.92) of IC assay, especially when we evaluated IgG and IgM combined after 10 days from the onset of symptoms with RT-PCR. However, we detected cross-reactivity between dengue and COVID-19 mainly with IgM antibodies (5 to 20% of cross-reaction) and demonstrated the need for better studies about diagnostic techniques for these diseases.