RESUMEN

Leptospira is a bacterial genus that includes several pathogenic species related to leptospirosis. In Colombia, leptospirosis is a mandatorily reported disease, widely distributed across the country. In the Villeta municipality, leptospirosis has been identified as an important cause of febrile illness; however, to date, no studies have been performed to identify the circulating species. A genus-specific qualitative qPCR was performed on DNA extracted from febrile patients' acute-phase whole-blood samples targeting a fragment of the rrs gene. Positive qPCR samples were further amplified for the adk, icdA, LipL32, LipL41, rrs, and secY genes through conventional PCR for sequencing. All high-quality obtained sequences were further assessed through concatenated phylogenetic analysis. A total of 25% (14/56) of febrile patients' acute blood samples were positive for Leptospira spp. High-quality sequences were obtained for only five genes, and analysis through concatenated phylogeny identified that all sequences clustered within the P1/pathogenic clade; some of them formed a robustly supported clade with Leptospira santarosai, and others were closely related with other Leptospira species but exhibited considerable genetic divergence. We describe the presence of pathogenic Leptospira species among febrile patients from the Villeta municipality and identify L. santarosai and other Leptospira species as causative agents of leptospirosis in the region.

RESUMEN

Introduction: Mayaro Fever (MF) is a tropical disease caused by the Mayaro virus (MAYV), with outbreaks documented in Latin America. Methods: A hospital-based fever surveillance in Leticia, Colombian Amazon, collected sera from 1,460 patients aged 5-89 between December 2020 and April 2023. Results: Dengue and malaria were the main diagnoses (19.4 and 5.8%, respectively), leaving 71.4% of cases unidentified after testing. Metagenomic sequencing and real-time RT-qPCR testing identified MAYV in two patients (25-year-old male and an 80-year-old female) exhibiting typical symptoms, of MF including rash, joint pain, and fever. Phylogenetics analysis of these two viruses revealed a close relationship to Peruvian strains within the MAYV D genotype. Discussion: The study of AFI in Leticia, Colombia, identified dengue as prevalent, with malaria, COVID-19, Influenza, and Zika viruses also detected. Despite extensive testing, most cases remained unexplained until metagenomic sequencing revealed MAYV, previously unseen in Colombia but known in neighboring countries. Conclusion: This study presents the first near full-length genomes of MAYV in Colombia, highlighting the need for further seroprevalence studies and enhanced surveillance to understand and control the spread of the virus in the region.

RESUMEN

Acute febrile illness (AFI) and severe neurological disorders (SNDs) often present diagnostic challenges due to their potential origins from a wide range of infectious agents. Nanopore metagenomics is emerging as a powerful tool for identifying the microorganisms potentially responsible for these undiagnosed clinical cases. In this study, we aim to shed light on the etiological agents underlying AFI and SND cases that conventional diagnostic methods have not been able to fully elucidate. Our approach involved analyzing samples from fourteen hospitalized patients using a comprehensive nanopore metagenomic approach. This process included RNA extraction and enrichment using the SMART-9N protocol, followed by nanopore sequencing. Subsequent steps involved quality control, host DNA/cDNA removal, de novo genome assembly, and taxonomic classification. Our findings in AFI cases revealed a spectrum of disease-associated microbes, including Escherichia coli, Streptococcus sp., Human Immunodeficiency Virus 1 (Subtype B), and Human Pegivirus. Similarly, SND cases revealed the presence of pathogens such as Escherichia coli, Clostridium sp., and Dengue virus type 2 (Genotype-II lineage). This study employed a metagenomic analysis method, demonstrating its efficiency and adaptability in pathogen identification. Our investigation successfully identified pathogens likely associated with AFI and SNDs, underscoring the feasibility of retrieving near-complete genomes from RNA viruses. These findings offer promising prospects for advancing our understanding and control of infectious diseases, by facilitating detailed genomic analysis which is critical for developing targeted interventions and therapeutic strategies.

Asunto(s)

Metagenómica , Secuenciación de Nanoporos , Humanos , Metagenómica/métodos , Secuenciación de Nanoporos/métodos , Masculino , Femenino , Enfermedades del Sistema Nervioso/microbiología , Enfermedades del Sistema Nervioso/genética , Enfermedades del Sistema Nervioso/virología , Adulto , Persona de Mediana Edad , Nanoporos , Anciano , Metagenoma/genética , Fiebre/microbiología , Fiebre/virología , Escherichia coli/genética

RESUMEN

Infectious disease (ID) cohorts are key to advancing public health surveillance, public policies, and pandemic responses. Unfortunately, ID cohorts often lack funding to store and share clinical-epidemiological (CE) data and high-dimensional laboratory (HDL) data long term, which is evident when the link between these data elements is not kept up to date. This becomes particularly apparent when smaller cohorts fail to successfully address the initial scientific objectives due to limited case numbers, which also limits the potential to pool these studies to monitor long-term cross-disease interactions within and across populations. CE data from 9 arbovirus (arthropod-borne viruses) cohorts in Latin America were retrospectively harmonized using the Maelstrom Research methodology and standardized to Clinical Data Interchange Standards Consortium (CDISC). We created a harmonized and standardized meta-cohort that contains CE and HDL data from 9 arbovirus studies from Latin America. To facilitate advancements in cross-population inference and reuse of cohort data, the Reconciliation of Cohort Data for Infectious Diseases (ReCoDID) Consortium harmonized and standardized CE and HDL from 9 arbovirus cohorts into 1 meta-cohort. Interested parties will be able to access data dictionaries that include information on variables across the data sets via Bio Studies. After consultation with each cohort, linked harmonized and curated human cohort data (CE and HDL) will be made accessible through the European Genome-phenome Archive platform to data users after their requests are evaluated by the ReCoDID Data Access Committee. This meta-cohort can facilitate various joint research projects (eg, on immunological interactions between sequential flavivirus infections and for the evaluation of potential biomarkers for severe arboviral disease).

Asunto(s)

Infecciones por Arbovirus , Humanos , Infecciones por Arbovirus/epidemiología , Estudios de Cohortes , América Latina/epidemiología , Masculino , Femenino , Niño , Arbovirus , Estudios Retrospectivos , Adolescente , Preescolar , Adulto

Asunto(s)

Fiebre Maculosa de las Montañas Rocosas , Humanos , Brasil/epidemiología , Fiebre Maculosa de las Montañas Rocosas/epidemiología

RESUMEN

COVID-19 is a zoonotic coronavirus disease caused by SARS-CoV-2. Its fast spreading by aerosol transmission has made it a highly contagious disease, causing the most recent 2020 pandemic. Although it mainly affects the respiratory system, atypical forms of the disease have been described, including developing an undifferentiated febrile illness without respiratory symptoms, that can represent a diagnostic challenge, mainly in tropical areas where several zoonotic febrile diseases are circulating. Thus, despite the broad clinical spectrum of COVID-19, in the tropics, other zoonotic etiologies should always be considered as differential diagnoses. According to our case reports review, eight different zoonotic febrile diseases misdiagnosed as COVID-19 have been reported in the available scientific literature of four databases. These were only suspected due to the epidemiological history. Thus, making a complete and detailed clinical history of a febrile patient in the tropics is essential to suspect the etiology and request the necessary confirmatory tests. Therefore, COVID-19 must be included as a differential diagnosis of undifferentiated febrile illness in the tropics, but other zoonotic infectious diseases must not be ruled out.

RESUMEN

BACKGROUND: The study of the etiology of acute febrile illness (AFI) has historically been designed as a prevalence of pathogens detected from a case series. This strategy has an inherent unrealistic assumption that all pathogen detection allows for causal attribution, despite known asymptomatic carriage of the principal causes of acute febrile illness in most low- and middle-income countries (LMICs). We designed a semi-quantitative PCR in a modular format to detect bloodborne agents of acute febrile illness that encompassed common etiologies of AFI in the region, etiologies of recent epidemics, etiologies that require an immediate public health response and additional pathogens of unknown endemicity. We then designed a study that would delineate background levels of transmission in the community in the absence of symptoms to provide corrected estimates of attribution for the principal determinants of AFI. METHODS: A case-control study of acute febrile illness in patients ten years or older seeking health care in Iquitos, Loreto, Peru, was planned. Upon enrollment, we will obtain blood, saliva, and mid-turbinate nasal swabs at enrollment with a follow-up visit on day 21-28 following enrollment to attain vital status and convalescent saliva and blood samples, as well as a questionnaire including clinical, socio-demographic, occupational, travel, and animal contact information for each participant. Whole blood samples are to be simultaneously tested for 32 pathogens using TaqMan array cards. Mid-turbinate samples will be tested for SARS-CoV-2, Influenza A and Influenza B. Conditional logistic regression models will be fitted treating case/control status as the outcome and with pathogen-specific sample positivity as predictors to attain estimates of attributable pathogen fractions for AFI. DISCUSSION: The modular PCR platforms will allow for reporting of all primary results of respiratory samples within 72 h and blood samples within one week, allowing for results to influence local medical practice and enable timely public health responses. The inclusion of controls will allow for a more accurate estimate of the importance of specific prevalent pathogens as a cause of acute illness. STUDY REGISTRATION: Project 1791, Registro de Proyectos de Investigación en Salud Pública (PRISA), Instituto Nacional de Salud, Perú.

Asunto(s)

COVID-19 , Gripe Humana , Humanos , Perú , Gripe Humana/epidemiología , Estudios de Casos y Controles , SARS-CoV-2 , Fiebre/epidemiología , Reacción en Cadena de la Polimerasa , Instituciones de Salud , Prueba de COVID-19

RESUMEN

Context: Acute febrile disease (AFI) in endemic tropical areas is a frequent reason for consulting the emergency services. Infection by 2 or more etiological agents may modify clinical and laboratory parameters, making diagnosis and treatment a challenge. Case report: We report the case of a patient who came from Africa and consults in Colombia, with AFI with thrombocytopenia that was eventually diagnosed to have concurrent infection with Plasmodium falciparum malaria and dengue. Conclusions: Dengue-malaria coinfection infection reports are scarce; it should be suspected in patients living or returning from areas where both diseases are endemic or during dengue outbreaks. This case serves as a reminder of this important condition that causes high morbidity and mortality if it is not early diagnosed and treated.

RESUMEN

Dengue virus (DENV) is the causal agent of dengue fever. The symptoms and signs of dengue vary from febrile illness to hemorrhagic syndrome. IFITM3 and TNFA are genes of the innate immune system. Variants IFITM3 (rs12252 T>C) and TNFA (rs1800629 G > A and rs361525 G>A) might alter gene expression and change the course of the disease. Our first objective was to determine whether these variants were associated with the susceptibility and severity of dengue. The second was to assess the association of these variants with each symptom. We studied 272 cases with suspected dengue infection, of which 102 were confirmed dengue cases (DENV+) and 170 were dengue-like cases without DENV infection (DENV-). Samples of 201 individuals from the general population of Mexico were included as a reference. Genotyping was performed by the polymerase chain reaction-restriction fragment length polymorphism technique. Odds ratios and confidence intervals were calculated using Pearson's chi-square test and later adjusted for age and sex with a binary logistic regression model. Haldane correction is applied when necessary. We found a significantly higher frequency of the A allele of TNFA rs361525 in both the DENV+ and DENV- groups compared with the general population. Focusing on DENV+ and DENV-, the frequency of the A allele of TNFA rs361525 was higher in the DENV+ group. A broad spectrum of symptoms was related to the A allele of both TNFA variants. We conclude that TNFA rs361525 increases the susceptibility to symptomatic dengue but can also be associated with susceptibility to other dengue-like symptoms from unknown causes.

Asunto(s)

Dengue , Humanos , Dengue/epidemiología , Reacción en Cadena de la Polimerasa , Alelos , México , Proteínas de la Membrana , Proteínas de Unión al ARN

RESUMEN

We assessed serum samples collected in Cauca Department, Colombia, from 486 persons for Orientia seroreactivity. Overall, 13.8% showed reactive IgG by indirect immunofluorescence antibody assay and ELISA. Of those samples, 30% (20/67) were confirmed to be positive by Western blot, showing >1 reactive band to Orientia 56-kD or 47-kD antigens.

Asunto(s)

Orientia tsutsugamushi , Infecciones por Rickettsia , Tifus por Ácaros , Humanos , Tifus por Ácaros/epidemiología , Colombia/epidemiología , Población Rural , Sensibilidad y Especificidad , Inmunoglobulina M , Anticuerpos Antibacterianos , Ensayo de Inmunoadsorción Enzimática , Orientia

RESUMEN

Arbovirus infections are frequent causes of acute febrile illness (AFI) in tropical countries. We conducted health facility-based AFI surveillance at four sites in Colombia (Cucuta, Cali, Villavicencio, Leticia) during 2019-2022. Demographic, clinical and risk factor data were collected from persons with AFI that consented to participate in the study (n = 2,967). Serologic specimens were obtained and tested for multiple pathogens by RT-PCR and rapid test (Antigen/IgM), with 20.7% identified as dengue positive from combined testing. Oropouche virus (OROV) was initially detected in serum by metagenomic next-generation sequencing (mNGS) and virus target capture in a patient from Cúcuta. Three additional infections from Leticia were confirmed by conventional PCR, sequenced, and isolated in tissue culture. Phylogenetic analysis determined there have been at least two independent OROV introductions into Colombia. To assess OROV spread, a RT-qPCR dual-target assay was developed which identified 87/791 (10.9%) viremic cases in AFI specimens from Cali (3/53), Cucuta (3/19), Villavicencio (38/566), and Leticia (43/153). In parallel, an automated anti-nucleocapsid antibody assay detected IgM in 27/503 (5.4%) and IgG in 92/568 (16.2%) patients screened, for which 24/68 (35.3%) of PCR positives had antibodies. Dengue was found primarily in people aged <18 years and linked to several clinical manifestations (weakness, skin rash and petechiae), whereas Oropouche cases were associated with the location, climate phase, and odynophagia symptom. Our results confirm OROV as an emerging pathogen and recommend increased surveillance to determine its burden as a cause of AFI in Colombia.

Asunto(s)

Infecciones por Bunyaviridae , Humanos , Colombia/epidemiología , Filogenia , Infecciones por Bunyaviridae/complicaciones , Infecciones por Bunyaviridae/epidemiología

RESUMEN

We conducted enhanced acute febrile illness surveillance in an urban slum community in Salvador, Brazil. We found that rickettsial infection accounted for 3.5% of urgent care visits for acute fever. Our results suggest that rickettsiae might be an underrecognized, treatable cause of acute febrile illness in impoverished urban populations in Brazil.

Asunto(s)

Infecciones por Rickettsia , Rickettsia , Anticuerpos Antibacterianos , Brasil/epidemiología , Fiebre/epidemiología , Humanos , Áreas de Pobreza , Infecciones por Rickettsia/diagnóstico , Infecciones por Rickettsia/epidemiología

RESUMEN

The Acute Febrile Illness (AFI) Surveillance Network in Belize is a country-wide active surveillance program aimed at diagnosing vector-borne, respiratory, and enteric pathogens among patients presenting to 11 participating hospitals and clinics with new onset fever. This study describes the epidemiology of dengue virus (DENV) infections in Belize diagnosed through AFI surveillance in 2020. Of the 894 patients enrolled and PCR-tested for DENV in this period, 44 DENV-positive cases (5%) were identified. All four DENV serotypes were detected, with two cases testing positive for DENV serotype 4, which is the first report of this serotype in Belize since 2004. The majority of DENV cases (66%) were diagnosed in the Belize District, which contains the largest urban center in the country (Belize City). Positive cases were detected between January 2020 and September 2020, with the majority (89%) diagnosed during the dry season between January and April, unlike years prior when cases were more often diagnosed during the wet season. Clinical signs and symptoms varied slightly between DENV serotypes. Active surveillance of DENV among AFI cases provides insight into the epidemiologic and clinical characteristics of DENV in Belize. This information is important for informing public health interventions to mitigate DENV transmission.

Asunto(s)

Virus del Dengue , Dengue , Virosis , Belice , Dengue/diagnóstico , Dengue/epidemiología , Virus del Dengue/genética , Fiebre/epidemiología , Humanos

RESUMEN

BACKGROUND: In malaria-endemic countries, febrile episodes caused by diseases other than malaria are a growing concern. However, limited knowledge of the prevalent etiologic agents and their geographic distributions restrict the ability of health services to address non-malarial morbidity and mortality through effective case management. Here, we review the etiology of fever in Latin America (LA) between 1980 and 2015 and map significant pathogens commonly implicated in febrile infectious diseases. METHODS: A literature search was conducted, without language restrictions, in three distinct databases in order to identify fever etiology studies that report laboratory-confirmed fever-causing pathogens that were isolated from usually sterile body sites. Data analyses and mapping was conducted with Tableau Desktop (version 2018.2.3). RESULTS: Inclusion criteria were met by 625 publications corresponding to data relative to 34 countries. Studies using serology (n = 339) predominated for viral infections, culture (n = 131) for bacteria, and microscopy (n = 62) for fungi and parasites. The pathogen groups most frequently reported were viral infections (n = 277), bacterial infections (n = 265), parasitic infections (n = 59), fungal infections (n = 47), and more than one pathogen group (n = 24). The most frequently reported virus was dengue virus (n = 171), followed by other arboviruses (n = 55), and hantavirus (n = 18). For bacteria, Staphylococcus spp. (n = 82), Rickettsia spp. (n = 70), and Leptospira spp. (n = 55) were frequently reported. Areas with biggest gaps on etiology of fever were apparent. CONCLUSIONS: This review provides a landscape of pathogens causing febrile illness other than malaria in LA for over 30 years. Our findings highlight the need to standardize protocols and report guidelines for fever etiology studies for better comparability of results and improved interpretation. Lastly, we should improve existing national laboratory surveillance systems, especially from low- to middle-income countries, to inform global fever policy priorities and timely identify emerging infections threats. STUDY REGISTRATION: PROSPERO systematic review registration number: CRD42016049281.

Asunto(s)

Fiebre/etiología , Femenino , Fiebre/patología , Humanos , América Latina , Masculino

RESUMEN

OBJECTIVE: To describe a severe case of infection by Leptospira in a woman in the northwest of Mexico. CASE REPORT: A 55-yearold woman from Sonora, México arrived at the Intensive Care Unit due to severe multiple organ failure primarily affecting the respiratory, renal and hepatic systems. Diagnostic tests were performed, and they were positive for anti-Leptospira antibodies, IgM and IgG; and spirochetes were observed on dark field microscopy and confirmed by Polymerase Chain Reaction (PCR). Doxycycline and platelet apheresis transfusion were used as treatment, which led to a very slow recovery. CONCLUSION: The information presented in this study may help in the identification of pathology caused by spirochetes. This case report is the first to present a case of severe leptospirosis in Sonora, México.

Asunto(s)

Leptospira , Leptospirosis , Insuficiencia Multiorgánica/microbiología , Antibacterianos/uso terapéutico , Anticuerpos Antibacterianos/sangre , Doxiciclina/uso terapéutico , Femenino , Humanos , Inmunoglobulina G/sangre , Inmunoglobulina M/sangre , Unidades de Cuidados Intensivos , Leptospira/genética , Leptospira/crecimiento & desarrollo , Leptospirosis/complicaciones , Leptospirosis/diagnóstico , Leptospirosis/microbiología , Leptospirosis/terapia , México , Microscopía/métodos , Persona de Mediana Edad , Insuficiencia Multiorgánica/diagnóstico , Insuficiencia Multiorgánica/etiología , Insuficiencia Multiorgánica/terapia , Transfusión de Plaquetas , Reacción en Cadena de la Polimerasa , Índice de Severidad de la Enfermedad

RESUMEN

BACKGROUND: Acute febrile illness (AFI) represent a significant health challenge in the Peruvian Amazon basin population due to their diverse etiologies and the unavailability of specific on-site diagnostic methods, resulting in underreporting of cases. In Peru, one of the most endemic regions to dengue and leptospirosis is Madre de Dios, a region also endemic to emergent bacterial etiologic agents of AFI, such as bartonellosis and rickettsiosis, whose prevalence is usually underreported. We aimed to molecularly identify the presence of Leptospira spp., Bartonella bacilliformis, and Rickettsia spp. by Polymerase Chain Reaction in serum samples from patients with AFI from Puerto Maldonado-Madre de Dios in Peru. METHODS: Serum samples from patients with acute febrile illness were analyzed by real-time PCR for detecting the presence of Bartonella bacilliformis, Leptospira spp. and Rickettsia spp. RESULTS: Bartonella bacilliformis was the most prevalent bacteria identified in 21.6% (30/139) of the samples, followed by Leptospira spp. in 11.5% (16/139) and Rickettsia spp. in 6.5% (9/139) of the samples. No co-infections were observed between these bacteria. The most frequent symptoms associated with fever among all groups, were headaches, myalgias, and arthralgias. We found no statistically significant differences in the clinical presentation between patients infected with each bacterium. CONCLUSIONS: In a previous study, we shown the presence of dengue, chikungunya, Zika and oropouche virus. We were able to identify these pathogens in 29.5% of all the samples, with chikungunya and OROV as the most frequently found in 9.4 and 8.6% of all the samples, respectively. In this study we show that B. bacilliformis (21.6%), Leptospira spp. (11.5%) and Rickettsia spp. (6.5%) accounted for the main etiologies of AFI in samples from Puerto Maldonado-Madre de Dios, Perú. Our analysis of their clinical presentation, further shows the importance of implementing more sensitive and specific on-site diagnostic tools in the national surveillance programs.This study confirms that the un-specificity of signs and symptoms is not only associated with arboviral infections, but also with the clinical presentation of endemic bacterial infections.

Asunto(s)

Infecciones por Bartonella , Bartonella bacilliformis/genética , Leptospira/genética , Leptospirosis , Infecciones por Rickettsia , Rickettsia/genética , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Infecciones por Bartonella/diagnóstico , Infecciones por Bartonella/epidemiología , Infecciones por Bartonella/genética , Infecciones por Bartonella/microbiología , Bartonella bacilliformis/aislamiento & purificación , Niño , Preescolar , Coinfección , Estudios Transversales , Femenino , Fiebre/diagnóstico , Fiebre/epidemiología , Fiebre/microbiología , Humanos , Lactante , Recién Nacido , Leptospira/aislamiento & purificación , Leptospirosis/diagnóstico , Leptospirosis/epidemiología , Leptospirosis/microbiología , Masculino , Persona de Mediana Edad , Tipificación Molecular , Perú/epidemiología , Prevalencia , Reacción en Cadena en Tiempo Real de la Polimerasa , Rickettsia/aislamiento & purificación , Infecciones por Rickettsia/diagnóstico , Infecciones por Rickettsia/epidemiología , Infecciones por Rickettsia/microbiología , Ríos , Sensibilidad y Especificidad , Adulto Joven

RESUMEN

BACKGROUND: The causes of acute febrile illness (AFI) in Latin America are diverse and their complexity increases as the proportion of fever due to malaria decreases, as malaria control measures and new pathogens emerge in the region. In this context, it is important to shed light on the gaps in the epidemiological characteristics and the geographic range for many AFI aetiologies. OBJECTIVES: To review studies on community-acquired fever aetiology other than malaria in Latin America, and to highlight knowledge gaps and challenges needing further investigation. SOURCES: PubMed from 2012 to April 2018. CONTENT: We found 17 eligible studies describing 13 539 patients. The median number of pathogens tested per individual was 3.5 (range 2-17). A causative pathogen could be determined for 6661 (49.2%) individuals. The most frequently reported pathogen during the study periods was dengue virus (DENV) (14 studies), followed by chikungunya virus (nine studies) and Zika virus (seven studies). Among the studies reporting concurrent infections, 296 individuals (2.2%) were found to have co-infections. In-hospital mortality was reported in eight (47%) studies, ranging between 0% and 18%. IMPLICATIONS: DENV fever is the febrile illness most frequently reported, reflecting its importance, while chikungunya and zika viruses present increasing trends since their emergence in the region. Studies with systematic and harmonized approaches for detection of multiple pathogens are needed and would probably reveal a higher burden of neglected pathogens such as Rickettsia spp. and arenaviruses. The lack of point-of-care tests and harmonized approach limits the care provided by health professionals and the efficacy of surveillance for AFI in the region.

Asunto(s)

Fiebre/epidemiología , Fiebre/etiología , Enfermedad Aguda , Coinfección/epidemiología , Coinfección/etiología , Fiebre/diagnóstico , Fiebre/terapia , Geografía Médica , Mortalidad Hospitalaria , Humanos , América Latina/epidemiología , Vigilancia de la Población , Prevalencia

RESUMEN

BACKGROUND: With their increasing availability in resource-limited settings, mobile phones may provide an important tool for participatory syndromic surveillance, in which users provide symptom data directly into a centralized database. OBJECTIVE: We studied the performance of a mobile phone app-based participatory syndromic surveillance system for collecting syndromic data (acute febrile illness and acute gastroenteritis) to detect dengue virus and norovirus on a cohort of children living in a low-resource and rural area of Guatemala. METHODS: Randomized households were provided with a mobile phone and asked to submit weekly reports using a symptom diary app (Vigilant-e). Participants reporting acute febrile illness or acute gastroenteritis answered additional questions using a decision-tree algorithm and were subsequently visited at home by a study nurse who performed a second interview and collected samples for dengue virus if confirmed acute febrile illness and norovirus if acute gastroenteritis. We analyzed risk factors associated with decreased self-reporting of syndromic data using the Vigilant-e app and evaluated strategies to improve self-reporting. We also assessed agreement between self-report and nurse-collected data obtained during home visits. RESULTS: From April 2015 to June 2016, 469 children in 207 households provided 471 person-years of observation. Mean weekly symptom reporting rate was 78% (range 58%-89%). Households with a poor (<70%) weekly reporting rate using the Vigilant-e app during the first 25 weeks of observation (n=57) had a greater number of children (mean 2.8, SD 1.5 vs mean 2.5, SD 1.3; risk ratio [RR] 1.2, 95% CI 1.1-1.4), were less likely to have used mobile phones for text messaging at study enrollment (61%, 35/57 vs 76.7%, 115/150; RR 0.6, 95% CI 0.4-0.9), and were less likely to access care at the local public clinic (35%, 20/57 vs 67.3%, 101/150; RR 0.4, 95% CI 0.2-0.6). Parents of female enrolled participants were more likely to have low response rate (57.1%, 84/147 vs 43.8%, 141/322; RR 1.4, 95% CI 1.1-1.9). Several external factors (cellular tower collapse, contentious elections) were associated with periods of decreased reporting. Poor response rate (<70%) was associated with lower case reporting of acute gastroenteritis, norovirus-associated acute gastroenteritis, acute febrile illness, and dengue virus-associated acute febrile illness (P<.001). Parent-reported syndromic data on the Vigilant-e app demonstrated agreement with nurse-collected data for fever (kappa=.57, P<.001), vomiting (kappa=.63, P<.001), and diarrhea (kappa=.61, P<.001), with decreased agreement as the time interval between parental report and nurse home visit increased (<1 day: kappa=.65-.70; ≥2 days: kappa=.08-.29). CONCLUSIONS: In a resource-limited area of rural Guatemala, a mobile phone app-based participatory syndromic surveillance system demonstrated a high reporting rate and good agreement between parental reported data and nurse-reported data during home visits. Several household-level and external factors were associated with decreased syndromic reporting. Poor reporting rate was associated with decreased syndromic and pathogen-specific case ascertainment.

Asunto(s)

Teléfono Celular/estadística & datos numéricos , Fiebre/terapia , Gastroenteritis/terapia , Aplicaciones Móviles/estadística & datos numéricos , Vigilancia de Guardia , Enfermedad Aguda , Adolescente , Niño , Preescolar , Estudios de Cohortes , Femenino , Guatemala , Humanos , Lactante , Recién Nacido , Masculino , Factores de Riesgo , Población Rural

Asunto(s)

Fallo Hepático Agudo/etiología , Proteínas de Neoplasias/genética , Neuroblastoma/complicaciones , Neuroblastoma/genética , Preescolar , Enfermedad Crítica/terapia , Servicio de Urgencia en Hospital , Humanos , Fallo Hepático Agudo/terapia , Masculino , Mutación , Proteínas de Neoplasias/deficiencia , Neuroblastoma/diagnóstico , Pronóstico , Enfermedades Raras , Diálisis Renal/métodos , Resultado del Tratamiento , Secuenciación del Exoma/métodos

RESUMEN

BACKGROUND: Malaria is endemic in countries located in tropical and sub-tropical regions. The increasing flow of domestic and international travellers has made malaria a relevant health problem even in non-endemic regions. Malaria has been described as the main diagnosis among travellers presenting febrile diseases after returning from tropical countries. In Brazil, malaria transmission occurs mainly in the Amazon region. Outside this area, malaria transmission is of low magnitude. METHODS: This cross-sectional study aimed to describe the experience in the diagnosis of malaria in a reference centre located outside the Brazilian Amazon Region, emphasizing the differences in clinical and laboratory markers between cases of malaria and those of other febrile diseases (OFD). Medical charts from adult patients (≥18 years) who underwent a thick smear test (TST) for malaria, between January 2001 and December 2014, were retrospectively reviewed. RESULTS: A total of 458 cases referred to perform the TST were included. Malaria was diagnosed in 193 (42 %) episodes. The remaining 265 episodes (58 %) were grouped as OFD. The majority of malaria episodes were acquired in the Brazilian Amazon Region. The median time between the onset of symptoms and the TST was 7 days. Only 53 (11.5 %) episodes were tested within the first 48 h after symptom onset. Comparing malaria with OFD, jaundice, nausea, vomiting, and reports of fever were more prevalent in the malaria group. Low platelet count and elevated bilirubin levels were also related to the diagnosis of malaria. CONCLUSIONS: The results indicate that outside the endemic area travellers presenting febrile disease suspected of being malaria underwent diagnostic test after considerable delay. The reporting of fever combined with a recent visit to an endemic area should promptly evoke the hypothesis of malaria. In these cases, specific diagnostic tests for malaria should be a priority. For cases that jump this step, the presence of elevated bilirubin or thrombocytopaenia should also indicate a diagnosis of malaria.

Asunto(s)

Pruebas Diagnósticas de Rutina/métodos , Fiebre/diagnóstico , Fiebre/epidemiología , Malaria/diagnóstico , Malaria/epidemiología , Viaje , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Brasil/epidemiología , Estudios Transversales , Femenino , Humanos , Masculino , Persona de Mediana Edad , Prevalencia , Estudios Retrospectivos , Adulto Joven