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1.
PLoS Negl Trop Dis ; 13(12): e0007978, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31877200

RESUMO

The 2015-2017 epidemics of Zika virus (ZIKV) in the Americas caused widespread infection, followed by protective immunity. The timing and burden of the next Zika virus outbreak remains unclear. We used an agent-based model to simulate the dynamics of age-specific immunity to ZIKV, and predict the future age-specific risk using data from Managua, Nicaragua. We also investigated the potential impact of a ZIKV vaccine. Assuming lifelong immunity, the risk of a ZIKV outbreak will remain low until 2035 and rise above 50% in 2047. The imbalance in age-specific immunity implies that people in the 15-29 age range will be at highest risk of infection during the next ZIKV outbreak, increasing the expected number of congenital abnormalities. ZIKV vaccine development and licensure are urgent to attain the maximum benefit in reducing the population-level risk of infection and the risk of adverse congenital outcomes. This urgency increases if immunity is not lifelong.


Assuntos
Fatores Etários , Efeitos Psicossociais da Doença , Surtos de Doenças , Infecção por Zika virus/epidemiologia , Infecção por Zika virus/imunologia , Zika virus/imunologia , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Simulação por Computador , Feminino , Humanos , Lactente , Recém-Nascido , Pessoa de Meia-Idade , Nicarágua/epidemiologia , Vacinas Virais/administração & dosagem , Vacinas Virais/imunologia , Adulto Jovem , Infecção por Zika virus/prevenção & controle
2.
Acta Trop ; 200: 105170, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31518572

RESUMO

Certain vector-borne organisms serve as etiological agents of equine disease. After previously identifying a new Ehrlichia species in horses from Mérida, we aimed to determine the infection frequency and screen for a wide range of vector-borne organisms from 93 tick-exposed, Ehrlichia seropositive horses in this region. PCR assays were performed to identify infection by organisms within the following genera: Anaplasma, Babesia, Bartonella, Ehrlichia, Leishmania, Mycoplasma, Neorickettsia, Rickettsia and Theileria. Overall, 90/93 horses (96.8%) were infected with one or more vector-borne organisms. Ninety (96.8%) horses were infected with Theileria equi and 21 (26.8%) with Babesia caballi. Nine (9.7%) horses were infected with the novel Ehrlichia species previously designated H7, reported in horses from Nicaragua and Brazil. Two horses (2.2%) were infected with Rickettsia felis. Anaplasma, Bartonella, Leishmania, Mycoplasma, or Neorickettsia species DNA was not amplified from any horse. Ticks collected from horses infected with vector-borne organisms were identified as Amblyomma cajennense sensu lato and Dermacentor nitens. Horses in Mérida are infected by a range of vector-borne organisms, including B. caballi, T. equi, Ehrlichia species H7, and R. felis. To the authors' knowledge, this constitutes the first report of molecular detection of R. felis in horses.


Assuntos
Vetores de Doenças , Ehrlichia/genética , Ehrlichia/isolamento & purificação , Ehrlichiose/diagnóstico , Cavalos/microbiologia , Infecções por Rickettsia/diagnóstico , Rickettsia felis/genética , Rickettsia felis/isolamento & purificação , Animais , Gatos , Ehrlichiose/epidemiologia , Nicarágua/epidemiologia , Infecções por Rickettsia/epidemiologia
3.
BMC Pregnancy Childbirth ; 19(1): 282, 2019 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-31391005

RESUMO

BACKGROUND: Until recently, Zika virus (ZIKV) infections were considered mild and self-limiting. Since 2015, they have been associated with an increase in microcephaly and other birth defects in newborns. While this association has been observed in case reports and epidemiological studies, the nature and extent of the relationship between ZIKV and adverse pregnancy and pediatric health outcomes is not well understood. With the unique opportunity to prospectively explore the full spectrum of issues related to ZIKV exposure during pregnancy, we undertook a multi-country, prospective cohort study to evaluate the association between ZIKV and pregnancy, neonatal, and infant outcomes. METHODS: At research sites in ZIKV endemic regions of Brazil (4 sites), Colombia, Guatemala, Nicaragua, Puerto Rico (2 sites), and Peru, up to 10,000 pregnant women will be recruited and consented in the first and early second trimesters of pregnancy and then followed through delivery up to 6 weeks post-partum; their infants will be followed until at least 1 year of age. Pregnant women with symptomatic ZIKV infection confirmed by presence of ZIKV RNA and/or IgM for ZIKV will also be enrolled, regardless of gestational age. Participants will be tested monthly for ZIKV infection; additional demographic, physical, laboratory and environmental data will be collected to assess the potential interaction of these variables with ZIKV infection. Delivery outcomes and detailed infant assessments, including physical and neurological outcomes, will be obtained. DISCUSSION: With the emergence of ZIKV in the Americas and its association with adverse pregnancy outcomes in this region, a much better understanding of the spectrum of clinical outcomes associated with exposure to ZIKV during pregnancy is needed. This cohort study will provide information about maternal, fetal, and infant outcomes related to ZIKV infection, including congenital ZIKV syndrome, and manifestations that are not detectable at birth but may appear during the first year of life. In addition, the flexibility of the study design has provided an opportunity to modify study parameters in real time to provide rigorous research data to answer the most critical questions about the impact of congenital ZIKV exposure. TRIAL REGISTRATION: NCT02856984 . Registered August 5, 2016. Retrospectively registered.


Assuntos
Anormalidades Congênitas/epidemiologia , Complicações Infecciosas na Gravidez/epidemiologia , Complicações na Gravidez/epidemiologia , Resultado da Gravidez/epidemiologia , Infecção por Zika virus/epidemiologia , Adolescente , Adulto , Anticorpos Antivirais/sangue , Brasil/epidemiologia , Estudos de Coortes , Colômbia/epidemiologia , Feminino , Retardo do Crescimento Fetal/epidemiologia , Guatemala/epidemiologia , Humanos , Imunoglobulina M , Lactente , Recém-Nascido , Masculino , Nicarágua/epidemiologia , Peru/epidemiologia , Pré-Eclâmpsia/epidemiologia , Gravidez , Primeiro Trimestre da Gravidez , Segundo Trimestre da Gravidez , Nascimento Prematuro/epidemiologia , Estudos Prospectivos , Porto Rico/epidemiologia , RNA Viral/sangue , Adulto Jovem , Zika virus
4.
Nat Med ; 25(6): 962-967, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31160818

RESUMO

Influenza viruses remain a severe threat to human health, causing up to 650,000 deaths annually1,2. Seasonal influenza virus vaccines can prevent infection, but are rendered ineffective by antigenic drift. To provide improved protection from infection, novel influenza virus vaccines that target the conserved epitopes of influenza viruses, specifically those in the hemagglutinin stalk and neuraminidase, are currently being developed3. Antibodies against the hemagglutinin stalk confer protection in animal studies4-6. However, no data exist on natural infections in humans, and these antibodies do not show activity in the hemagglutination inhibition assay, the hemagglutination inhibition titer being the current correlate of protection against influenza virus infection7-9. While previous studies have investigated the protective effect of cellular immune responses and neuraminidase-inhibiting antibodies, additional serological correlates of protection from infection could aid the development of broadly protective or universal influenza virus vaccines10-13. To address this gap, we performed a household transmission study to identify alternative correlates of protection from infection and disease in naturally exposed individuals. Using this study, we determined 50% protective titers and levels for hemagglutination inhibition, full-length hemagglutinin, neuraminidase and hemagglutinin stalk-specific antibodies. Further, we found that hemagglutinin stalk antibodies independently correlated with protection from influenza virus infection.


Assuntos
Vírus da Influenza A Subtipo H1N1/imunologia , Influenza Humana/imunologia , Influenza Humana/prevenção & controle , Adolescente , Adulto , Idoso , Anticorpos Antivirais/sangue , Criança , Pré-Escolar , Estudos de Coortes , Feminino , Testes de Inibição da Hemaglutinação , Glicoproteínas de Hemaglutininação de Vírus da Influenza/imunologia , Humanos , Lactente , Recém-Nascido , Influenza Humana/epidemiologia , Masculino , Pessoa de Meia-Idade , Nicarágua/epidemiologia , Pandemias/prevenção & controle , Adulto Jovem
5.
Nat Commun ; 10(1): 1246, 2019 03 18.
Artigo em Inglês | MEDLINE | ID: mdl-30886145

RESUMO

The understanding of immunological interactions among the four dengue virus (DENV) serotypes and their epidemiological implications is often hampered by the lack of individual-level infection history. Using a statistical framework that infers full infection history, we analyze a prospective pediatric cohort in Nicaragua to characterize how infection history modulates the risks of DENV infection and subsequent clinical disease. After controlling for age, one prior infection is associated with 54% lower, while two or more are associated with 91% higher, risk of a new infection, compared to DENV-naive children. Children >8 years old have 55% and 120% higher risks of infection and subsequent disease, respectively, than their younger peers. Among children with ≥1 prior infection, intermediate antibody titers increase, whereas high titers lower, the risk of subsequent infection, compared with undetectable titers. Such complex dependency needs to be considered in the design of dengue vaccines and vaccination strategies.


Assuntos
Anticorpos Antivirais/sangue , Vírus da Dengue/patogenicidade , Dengue/imunologia , Interações entre Hospedeiro e Microrganismos/imunologia , Vacinação/métodos , Adolescente , Fatores Etários , Anticorpos Antivirais/imunologia , Criança , Pré-Escolar , Reações Cruzadas/genética , Reações Cruzadas/imunologia , Dengue/sangue , Dengue/epidemiologia , Dengue/virologia , Vírus da Dengue/genética , Vírus da Dengue/imunologia , Vírus da Dengue/isolamento & purificação , Feminino , Humanos , Masculino , Nicarágua/epidemiologia , Estudos Prospectivos , Fatores de Risco , Sorogrupo , Virulência/genética , Virulência/imunologia
6.
PLoS Med ; 16(1): e1002726, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30668565

RESUMO

BACKGROUND: Zika virus (ZIKV) emerged in northeast Brazil in 2015 and spread rapidly across the Americas, in populations that have been largely exposed to dengue virus (DENV). The impact of prior DENV infection on ZIKV infection outcome remains unclear. To study this potential impact, we analyzed the large 2016 Zika epidemic in Managua, Nicaragua, in a pediatric cohort with well-characterized DENV infection histories. METHODS AND FINDINGS: Symptomatic ZIKV infections (Zika cases) were identified by real-time reverse transcription PCR and serology in a community-based cohort study that follows approximately 3,700 children aged 2-14 years old. Annual blood samples were used to identify clinically inapparent ZIKV infections using a novel, well-characterized serological assay. Multivariable Poisson regression was used to examine the relation between prior DENV infection and incidence of symptomatic and inapparent ZIKV infection. The generalized-growth method was used to estimate the effective reproduction number. From January 1, 2016, to February 28, 2017, 560 symptomatic ZIKV infections and 1,356 total ZIKV infections (symptomatic and inapparent) were identified, for an overall incidence of 14.0 symptomatic infections (95% CI: 12.9, 15.2) and 36.5 total infections (95% CI: 34.7, 38.6) per 100 person-years. Effective reproduction number estimates ranged from 3.3 to 3.4, depending on the ascending wave period. Incidence of symptomatic and total ZIKV infections was higher in females and older children. Analysis of the effect of prior DENV infection was performed on 3,027 participants with documented DENV infection histories, of which 743 (24.5%) had experienced at least 1 prior DENV infection during cohort follow-up. Prior DENV infection was inversely associated with risk of symptomatic ZIKV infection in the total cohort population (incidence rate ratio [IRR]: 0.63; 95% CI: 0.48, 0.81; p < 0.005) and with risk of symptomatic presentation given ZIKV infection (IRR: 0.62; 95% CI: 0.44, 0.86) when adjusted for age, sex, and recent DENV infection (1-2 years before ZIKV infection). Recent DENV infection was significantly associated with decreased risk of symptomatic ZIKV infection when adjusted for age and sex, but not when adjusted for prior DENV infection. Prior or recent DENV infection did not affect the rate of total ZIKV infections. Our findings are limited to a pediatric population and constrained by the epidemiology of the site. CONCLUSIONS: These findings support that prior DENV infection may protect individuals from symptomatic Zika. More research is needed to address the possible immunological mechanism(s) of cross-protection between ZIKV and DENV and whether DENV immunity also modulates other ZIKV infection outcomes such as neurological or congenital syndromes.


Assuntos
Dengue/epidemiologia , Infecção por Zika virus/epidemiologia , Adolescente , Criança , Pré-Escolar , Estudos de Coortes , Dengue/complicações , Vírus da Dengue , Feminino , Humanos , Masculino , Nicarágua/epidemiologia , Reação em Cadeia da Polimerase em Tempo Real , Fatores de Risco , Zika virus , Infecção por Zika virus/etiologia
7.
BMC Nephrol ; 20(1): 21, 2019 01 16.
Artigo em Inglês | MEDLINE | ID: mdl-30651081

RESUMO

BACKGROUND: After two-years of follow-up of 263 apparently healthy 18- to 30-year-old men in communities affected by Mesoamerican nephropathy (MeN), we identified three distinct case groups: a subgroup with (i) established renal dysfunction (case-group 1); individuals with (ii) a rapid decline in kidney function (case-group 2); and individuals with (iii) stable kidney function (non-cases). This paper investigates whether local tests are potentially useful for the timely identification of these case groups. METHODS: Creatinine levels were measured in local laboratories every six months for two years. Aliquots were sent to a centralized laboratory for measurements of cystatin C and creatinine levels. We investigated agreement between the locally and centrally measured creatinine-based Chronic Kidney disease Epidemiology Collaboration (CKD-EPI) equation for estimating the Glomerular Filtration Rate (eGFR). A logistic regression analysis was used to assess predictive factors for case groups 1 and 2 compared to non-cases. Predictive variables were locally measured eGFR, and urinary neutrophil gelatinase-associated lipocalin (uNGAL) levels. The discrimination performance of the model was assessed using the area under the receiver operating characteristic curve (AUC). RESULTS: Considerable variation in local eGFR measurements was observed. The prediction model for case-group 1 included baseline kidney function and with or without uNGAL (AUC = 0.98, 95% confidence interval (CI), 0.91-1.00). The prediction model for case-group 2 also required eGFRScr at six and twelve months after baseline, with or without uNGAL levels (AUC = 0.88; 95% CI 0.80-0.99). CONCLUSIONS: Established renal dysfunction was detected at a single time point using local measurements and uNGAL. For the detection of a rapid decline in kidney function over time, at least 2 more measurements at six and twelve months are needed.


Assuntos
Testes de Função Renal , Rim/fisiopatologia , Insuficiência Renal Crônica/epidemiologia , Adolescente , Adulto , Albuminúria/etiologia , Albuminúria/urina , Área Sob a Curva , Creatinina/sangue , Creatinina/urina , Cistatina C/sangue , Progressão da Doença , Doenças Endêmicas , Seguimentos , Taxa de Filtração Glomerular , Humanos , Lipocalina-2/sangue , Masculino , Nicarágua/epidemiologia , Curva ROC , Insuficiência Renal Crônica/sangue , Insuficiência Renal Crônica/fisiopatologia , Insuficiência Renal Crônica/urina , Risco , Inquéritos e Questionários , Adulto Jovem
8.
Am J Orthopsychiatry ; 89(2): 296-303, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30102059

RESUMO

Homelessness is a global phenomenon that affects groups in situations of poverty and social exclusion, in both developed and developing nations. However, the scientific literature on homeless people in developing countries is scant. This work shows the difficulties defining homelessness and examines the necessary criteria for who will be deemed a homeless person in a developing country. Furthermore, the results of the Point-In-Time (PIT) count of homeless people-a measure of the number of homeless people on a specific day-done in the city of León, Nicaragua (population: 185,000). Throughout the PIT count, 82 unduplicated people living in homelessness were tallied (76% male, 23% female), of which 47 answered a questionnaire. Most of the homeless people in León are male, mestizo, of Nicaraguan nationality, with a primary level education or less, and in a situation of chronic homelessness. Results showed a mean age of 47 years for these individuals. Most of the homeless people showed a bad physical appearance, had poor personal hygiene, and wore dirty clothing. Around half of the homeless observed seemed to have problems related to mental health, alcohol, and/or drugs. (PsycINFO Database Record (c) 2019 APA, all rights reserved).


Assuntos
Países em Desenvolvimento/estatística & dados numéricos , Pessoas em Situação de Rua/estatística & dados numéricos , Transtornos Mentais/epidemiologia , Feminino , Pessoas em Situação de Rua/classificação , Pessoas em Situação de Rua/psicologia , Humanos , Higiene , Masculino , Pessoa de Meia-Idade , Nicarágua/epidemiologia , Aparência Física , Pobreza
10.
Kidney Int ; 94(6): 1205-1216, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30466566

RESUMO

An epidemic of chronic kidney disease (CKD) of unknown etiology, known as Mesoamerican Nephropathy (MeN), has been ongoing in Latin America for at least two decades. MeN primarily affects young adults without traditional CKD risk factors, and agricultural workers are disproportionately afflicted. We previously identified an acute phase of MeN that involves acute kidney injury (AKI) with tubulointerstitial nephritis and systemic inflammation. Because clinical disease progression in MeN is not yet understood, we sought to determine clinical predictors for progression from acute MeN to CKD. Through ongoing surveillance in Nicaragua, local physicians reported cases of acute MeN and CKD among agricultural workers. We analyzed clinical data collected during the acute MeN encounter to identify factors associated with progression to CKD. From February 2015 to May 2017, 586 agricultural workers (median age 27.8 years, 90% male) presented with acute MeN. The majority had a normal baseline creatinine, and leukocyturia (98.8%) and peripheral leukocytosis (80.7%) were common. Ultimately, 49 (8.4%) progressed to CKD, the majority of those within 6 months. CKD was attributed to MeN in all cases, and none had diabetes or hypertension. The strongest predictors of CKD progression were anemia and paresthesias at presentation, while leukocytosis was associated with renal recovery. Clinical markers of acute MeN may help clinicians identify patients at high risk for rapid progression to CKD, which in turn can inform early clinical management. Future studies should seek to determine the underlying etiology of disease and identify optimal interventions to interrupt the pathophysiologic process of MeN.


Assuntos
Lesão Renal Aguda/patologia , Nefrite Intersticial/patologia , Insuficiência Renal Crônica/diagnóstico , Lesão Renal Aguda/sangue , Adulto , Biomarcadores/análise , Progressão da Doença , Feminino , Taxa de Filtração Glomerular , Humanos , Incidência , Masculino , Nicarágua/epidemiologia , Prognóstico , Estudos Prospectivos , Insuficiência Renal Crônica/epidemiologia , Insuficiência Renal Crônica/patologia , Medição de Risco/métodos , Fatores de Risco , Adulto Jovem
11.
Parasit Vectors ; 11(1): 585, 2018 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-30419951

RESUMO

BACKGROUND: Vector-borne diseases constitute a major problem for veterinary and public health, especially in tropical regions like Central America. Domestic dogs may be infected with several vector-borne pathogens of zoonotic relevance, which may also severely compromise canine health. METHODS: To assess the prevalence of canine vector-borne diseases in Nicaragua, 329 dogs from seven cities, which were presented to the veterinarian for various reasons, were included in this study. Dogs were examined clinically and diagnostic blood samples were taken for analysis of packed cell volume (PCV) and presence of microfilariae as well as antigen of Dirofilaria immitis and antibodies to Ehrlichia spp., Anaplasma spp. and Borrelia burgdorferi (sensu lato) by use of a commercially available rapid ELISA. To detect current infections, specific PCRs for the detection of E. canis, A. platys and A. phagocytophilum were carried out on blood samples of the respective seropositive dogs. Microfilaremic blood samples, as well as D. immitis antigen positive samples were further subjected to PCR and subsequent sequencing for filarial species identification. RESULTS: Antibodies against Ehrlichia spp. were present in 62.9% of dogs, while Anaplasma spp. seroprevalence was 28.6%. Antibodies against species of both genera were detected in 24.9% of dogs. Borrelia burgdorferi (s.l.) antibodies were not detected. Dirofilaria immitis antigen was present in six animals (1.8%), two of which also showed D. immitis microfilariae in buffy coat. In addition to D. immitis, Acanthocheilonema reconditum was identified by PCR and sequencing in two of four additional microfilaremic blood samples, which were tested negative for D. immitis antigen. Current E. canis infections as defined by DNA detection were present in 58.5% of Ehrlichia-seropositive dogs, while 5.3% of Anaplasma-seropositive dogs were PCR-positive for A. platys, 2.2% for A. phagocytophilum and 16.0% for both Anaplasma species. Current E. canis infection had a statistically significant negative impact on PCV, whereas no relationship between infection status and clinical signs of disease could be observed. CONCLUSIONS: These results indicate that canine vector-borne diseases are widespread in Nicaragua and that dogs may constitute a reservoir for human infection with E. canis, A. phagocytophilum and D. immitis. Thus, the use of repellents or acaricides to protect dogs from vector-borne diseases is strongly recommended.


Assuntos
Reservatórios de Doenças/veterinária , Vetores de Doenças , Doenças do Cão/epidemiologia , Doenças do Cão/imunologia , Estudos Soroepidemiológicos , Anaplasma/imunologia , Anaplasma/isolamento & purificação , Anaplasmose/epidemiologia , Anaplasmose/transmissão , Animais , Anticorpos Antibacterianos/sangue , Anticorpos Anti-Helmínticos/sangue , Antígenos de Bactérias/sangue , Antígenos de Helmintos/sangue , Borrelia burgdorferi/imunologia , Borrelia burgdorferi/isolamento & purificação , Dirofilaria immitis/imunologia , Dirofilariose/epidemiologia , Dirofilariose/transmissão , Reservatórios de Doenças/parasitologia , Doenças do Cão/microbiologia , Doenças do Cão/parasitologia , Cães , Ehrlichia/imunologia , Ehrlichia/isolamento & purificação , Ehrlichia canis/imunologia , Ehrlichia canis/isolamento & purificação , Ehrlichiose/epidemiologia , Ehrlichiose/transmissão , Ehrlichiose/veterinária , Humanos , Doença de Lyme/epidemiologia , Doença de Lyme/transmissão , Doença de Lyme/veterinária , Masculino , Nicarágua/epidemiologia
12.
Am J Trop Med Hyg ; 99(6): 1591-1597, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30298802

RESUMO

The prevalence and intensity of soil-transmitted helminth (STH) infections in schoolchildren from Corn Islands (Nicaragua) were examined to detect mono- or poly-STH infected children, measuring different intensity levels, and to elucidate measurably increased odds of being anemic. A total of 341 stool samples provided by 2- to 15-year-old children were examined using a concentration technique and a Kato-Katz slide. Intensity of infection was expressed as eggs per gram (epg) of feces to classify light, moderate, or heavy intensity infection. A finger-prick blood sample was obtained from each student in the field. Soil-transmitted helminth prevalence was 54.3%, with Trichuris trichiura as the most prevalent species (48.9%). The combination T. trichiura/Ascaris lumbricoides (12.6%) was the most common. When T. trichiura or A. lumbricoides appeared as a single infection, light or moderate intensity infections were seen, whereas when multiple species were identified, heavy infections were present. Anemia was detected in those with any kind of STH infection (42.7%), with statistically significant differences (P = 0.004) when compared with uninfected individuals (28.2%). Polyparasite infection with one parasite species at moderate intensity and the other parasite species at light intensity or absent was found to be a significant factor for the odds of being anemic (odds ratio = 2.07). The present study reveals a high level of STH transmission requiring a deworming control program in Corn Islands and pointing to the need of improving the education and sanitary conditions of the population to avoid environmental contamination and reinfection.


Assuntos
Anemia/epidemiologia , Ascaríase/epidemiologia , Ascaris lumbricoides/isolamento & purificação , Tricuríase/epidemiologia , Trichuris/isolamento & purificação , Adolescente , Anemia/complicações , Anemia/parasitologia , Animais , Ascaríase/complicações , Ascaríase/parasitologia , Ascaríase/transmissão , Ascaris lumbricoides/classificação , Criança , Pré-Escolar , Coinfecção , Fezes/parasitologia , Feminino , Humanos , Ilhas/epidemiologia , Masculino , Nicarágua/epidemiologia , Contagem de Ovos de Parasitas , Prevalência , Instituições Acadêmicas , Solo/parasitologia , Tricuríase/complicações , Tricuríase/parasitologia , Tricuríase/transmissão , Trichuris/classificação
13.
Emerg Infect Dis ; 24(10): 1882-1888, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30226161

RESUMO

During August 2012-November 2014, we conducted a case ascertainment study to investigate household transmission of influenza virus in Managua, Nicaragua. We collected up to 5 respiratory swab samples from each of 536 household contacts of 133 influenza virus-infected persons and assessed for evidence of influenza virus transmission. The overall risk for influenza virus infection of household contacts was 15.7% (95% CI 12.7%-19.0%). Oseltamivir treatment of index patients did not appear to reduce household transmission. The mean serial interval for within-household transmission was 3.1 (95% CI 1.6-8.4) days. We found the transmissibility of influenza B virus to be higher than that of influenza A virus among children. Compared with households with <4 household contacts, those with >4 household contacts appeared to have a reduced risk for infection. Further research is needed to model household influenza virus transmission and design interventions for these settings.


Assuntos
Características da Família , Influenza Humana/epidemiologia , Influenza Humana/transmissão , Saúde da População Urbana , Adolescente , Fatores Etários , Criança , Pré-Escolar , Feminino , História do Século XXI , Humanos , Lactente , Recém-Nascido , Vírus da Influenza A/classificação , Vírus da Influenza A/genética , Influenza Humana/história , Influenza Humana/virologia , Masculino , Nicarágua/epidemiologia , Vigilância da População , Fatores Socioeconômicos
14.
Proc Natl Acad Sci U S A ; 115(42): 10762-10767, 2018 10 16.
Artigo em Inglês | MEDLINE | ID: mdl-30266790

RESUMO

Dengue virus (DENV) is the most prevalent human vector-borne viral disease. The force of infection (FoI), the rate at which susceptible individuals are infected in a population, is an important metric for infectious disease modeling. Understanding how and why the FoI of DENV changes over time is critical for developing immunization and vector control policies. We used age-stratified seroprevalence data from 12 years of the Pediatric Dengue Cohort Study in Nicaragua to estimate the annual FoI of DENV from 1994 to 2015. Seroprevalence data revealed a change in the rate at which children acquire DENV-specific immunity: in 2004, 50% of children age >4 years were seropositive, but by 2015, 50% seropositivity was reached only by age 11 years. We estimated a spike in the FoI in 1997-1998 and 1998-1999 and a gradual decline thereafter, and children age <4 years experienced a lower FoI. Two hypotheses to explain the change in the FoI were tested: (i) a transition from introduction of specific DENV serotypes to their endemic transmission and (ii) a population demographic transition due to declining birth rates and increasing life expectancy. We used mathematical models to simulate these hypotheses. We show that the initial high FoI can be explained by the introduction of DENV-3 in 1994-1998, and that the overall gradual decline in the FoI can be attributed to demographic shifts. Changes in immunity and demographics strongly impacted DENV transmission in Nicaragua. Population-level measures of transmission intensity are dynamic and thus challenging to use to guide vaccine implementation locally and globally.


Assuntos
Anticorpos Antivirais/sangue , Vírus da Dengue/isolamento & purificação , Dengue/epidemiologia , Dengue/transmissão , Estudos Soroepidemiológicos , Adolescente , Criança , Pré-Escolar , Dengue/virologia , Feminino , Humanos , Masculino , Nicarágua/epidemiologia , Estudos Prospectivos , Vigilância em Saúde Pública , Fatores de Tempo
15.
Ticks Tick Borne Dis ; 9(6): 1565-1572, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-30098931

RESUMO

The neotropical climate of Central America provides ideal conditions for ticks, which may transmit several human pathogens, including spotted-fever group Rickettsia. Dogs may act as sentinels or reservoirs for human tick-borne diseases due to shared tick species. Here, ticks were collected from 680 client-owned dogs in Nicaragua and Costa Rica, and a total of 316 tick pools were investigated for Rickettsia infection by quantitative real-time PCR (qPCR) targeting the gltA gene. Subsequently, up to six further genomic targets (16S rDNA, gltA, sca4, ompA, ompB and the 23S-5S intergenic spacer) were investigated for Rickettsia species determination. The predominant tick species was Rhipicephalus sanguineus sensu lato (s.l.) (19.9% of dogs infested in Costa Rica, 48.0% in Nicaragua), followed by Ixodes boliviensis (3.1% in Costa Rica / none in Nicaragua) and Amblyomma ovale (4.8% in Costa Rica, 0.9% in Nicaragua). In total, 22 of 316 tick pools containing 60 of 1023 individual ticks were Rickettsia-positive as determined by qPCR, resulting in a minimum infection rate (MIR) of 2.2%. In detail, MIR in Rh. sanguineus s.l. was 0.7% (7/281 pools), in I. boliviensis 33.3% (12/13 pools) and in A. ovale 9.7% (3/22 pools). For 11 of 12 positive I. boliviensis pools and one of six positive Rh. sanguineus s.l. pools, the species could be determined as R. monacensis. R. amblyommatis was identified in one Rh. sanguineus s.l. pool from Costa Rica and one A. ovale pool from Nicaragua. Nine of 12 R. monacensis-positive tick pools were collected in San Rafael de Heredia, Costa Rica, indicating a high local occurrence in this area. This study supports recent evidence that R. monacensis is present on the American continent. Its high local occurrence among dog-associated I. boliviensis, which may also parasitize humans, in Costa Rica gives cause for concern, as R. monacensis is also pathogenic to humans.


Assuntos
Doenças do Cão/epidemiologia , Infecções por Rickettsia/veterinária , Rickettsia/isolamento & purificação , Carrapatos/fisiologia , Animais , Costa Rica/epidemiologia , Doenças do Cão/parasitologia , Cães , Humanos , Larva/crescimento & desenvolvimento , Larva/fisiologia , Nicarágua/epidemiologia , Ninfa/crescimento & desenvolvimento , Ninfa/fisiologia , Reação em Cadeia da Polimerase em Tempo Real/veterinária , Infecções por Rickettsia/epidemiologia , Infecções por Rickettsia/parasitologia , Risco , Carrapatos/crescimento & desenvolvimento
16.
Rev Gastroenterol Peru ; 38(2): 131-137, 2018.
Artigo em Espanhol | MEDLINE | ID: mdl-30118458

RESUMO

INTRODUCTION: Few pediatric studies classify the irritable bowel syndrome (IBS) subtypes. OBJECTIVE: To describe the characteristics and subtypes of IBS in children from Panama, Ecuador, El Salvador, Nicaragua and Mexico. MATERIAL AND METHODS: Prevalence study performed in children between 8 and 18 years of age with a diagnosis of IBS. The children answered the Questionnaire for Pediatric Gastrointestinal Symptoms Roma III for Schoolchildren and Adolescents (QPGS-III) to identify functional gastrointestinal disorders. Variables such as age and sex were taken into account. The subtypes of IBS were classified in IBS with constipation (IBS-c), with diarrhea (IBS-d), mixed (IBS-m) and without subtype (IBS-ss). Statistical analysis included measures of central tendency, two-tailed student t-test, chi-square test, and Fisher's exact test, with a significant p<0.05. RESULTS: We included 79 children (54.4% female, 12.1±2.1 years) presenting IBS-ss in 55.7%, IBS-c in 15.2%, IBS-m in 15.2% and SII-d in 13.9%. Severe pain predominated most of the day and with mucous stools; possible associations for IBS-d school and sex. CONCLUSION: After IBS-ss, the IBS-e, IBS-d and IBS-m are similar, being the possible risk factors for IBS-d, the public school and the female gender.


Assuntos
Síndrome do Intestino Irritável/classificação , Síndrome do Intestino Irritável/epidemiologia , Adolescente , Criança , Equador/epidemiologia , El Salvador/epidemiologia , Feminino , Humanos , Síndrome do Intestino Irritável/diagnóstico , Masculino , México/epidemiologia , Nicarágua/epidemiologia , Prevalência , Fatores de Risco
17.
Proc Natl Acad Sci U S A ; 115(37): 9294-9299, 2018 09 11.
Artigo em Inglês | MEDLINE | ID: mdl-30150394

RESUMO

In 2015, a Zika epidemic in Brazil began spreading throughout the Americas. Zika virus (ZIKV) entered Managua, Nicaragua, in January 2016 and caused an epidemic that peaked in July-September 2016. ZIKV seropositivity was estimated among participants of pediatric (n = 3,740) and household (n = 2,147) cohort studies, including an adult-only subset from the household cohort (n = 1,074), in Managua. Seropositivity was based on a highly sensitive and specific assay, the Zika NS1 blockade-of-binding ELISA, which can be used in dengue-endemic populations. Overall seropositivity for the pediatric (ages 2-14), household (ages 2-80), and adult (ages 15-80) cohorts was 36, 46, and 56%, respectively. Trend, risk factor, and contour mapping analyses demonstrated that ZIKV seroprevalence increased nonlinearly with age and that body surface area was statistically associated with increasing seroprevalence in children. ZIKV seropositivity was higher in females than in males across almost all ages, with adjusted prevalence ratios in children and adults of 1.11 (95% CI: 1.02-1.21) and 1.14 (95% CI: 1.01-1.28), respectively. No household-level risk factors were statistically significant in multivariate analyses. A spatial analysis revealed a 10-15% difference in the risk of ZIKV infections across our 3-km-wide study site, suggesting that ZIKV infection risk varies at small spatial scales. To our knowledge, this is the largest ZIKV seroprevalence study reported in the Americas, and the only one in Central America and in children to date. It reveals a high level of immunity against ZIKV in Managua as a result of the 2016 epidemic, making a second large Zika epidemic unlikely in the near future.


Assuntos
Epidemias , Infecção por Zika virus/epidemiologia , Zika virus , Adolescente , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Nicarágua/epidemiologia , Fatores de Risco , Estudos Soroepidemiológicos , Fatores Sexuais
18.
Glob Health Action ; 11(1): 1428467, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29975179

RESUMO

BACKGROUND: Nicaraguans have migrated internally and internationally for centuries due to economic, political and sociocultural factors. Deficiencies in the country's health care system have produced inequities in people's access to health care and medicines. Remittances have become an important source of income, partly invested in health. OBJECTIVES: The overall aim of the study was to analyse migration-health relations in contemporary Nicaragua within a broader context of socio-economic transformations. METHODS: The study uses a mixed-methods approach, combining qualitative interview data and quantitative survey data. RESULTS: The findings show that migration is commonly practised as a strategy for making a living and is related to the struggle for a better life. Health concerns are indirectly embedded in people's mobile livelihoods, but also directly influence migration motives. Furthermore, migration involves both advantages and disadvantages for health. Physical and sexual violence can come to an end for migrating women, health care and medicine can become more accessible for internal migrants, and vulnerabilities caused by environmental disasters can be avoided by moving. Moreover, remittances can improve people's everyday life and health. Yet migration can also be a stressful and health-damaging event. International migrants, particularly the undocumented, can have problems accessing health care, and also experience much danger at border crossings. Transnational families can suffer emotionally as well as physically due to separation. Findings from the survey show that family members of migrants do not rate their physical health as good as often as non-migrating families. CONCLUSIONS: The Nicaraguan population is not guaranteed its social rights of citizenship. This results in mobile livelihoods and the need for translocal social support (e.g. remittances). Migration can have both positive and negative effects on health for migrants and their family members; geographical distance and social differences are key to the outcome.


Assuntos
Emigração e Imigração/estatística & dados numéricos , Renda/estatística & dados numéricos , Motivação , Migrantes/psicologia , Família/psicologia , Acesso aos Serviços de Saúde , Nível de Saúde , Humanos , Nicarágua/epidemiologia , Apoio Social , Fatores Socioeconômicos
19.
PLoS Negl Trop Dis ; 12(7): e0006670, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-30059496

RESUMO

Chikungunya virus (CHIKV) has been detected sporadically since the 1950s and includes three distinct co-circulating genotypes. In late 2013, the Asian genotype of CHIKV was responsible for the Caribbean outbreak (CO) that rapidly became an epidemic throughout the Americas. There is a limited understanding of the molecular evolution of CHIKV in the Americas during this epidemic. We sequenced 185 complete CHIKV genomes collected mainly from Nicaragua in Central America and Florida in the United States during the 2014-2015 Caribbean/Americas epidemic. Our comprehensive phylogenetic analyses estimated the epidemic history of the Asian genotype and the recent Caribbean outbreak (CO) clade, revealed considerable genetic diversity within the CO clade, and described different epidemiological dynamics of CHIKV in the Americas. Specifically, we identified multiple introductions in both Nicaragua and Florida, with rapid local spread of viruses in Nicaragua but limited autochthonous transmission in Florida in the US. Our phylogenetic analysis also showed phylogeographic clustering of the CO clade. In addition, we identified the significant amino acid substitutions that were observed across the entire Asian genotype during its evolution and examined amino acid changes that were specific to the CO clade. Deep sequencing analysis identified specific minor variants present in clinical specimens below-consensus levels. Finally, we investigated the association between viral phylogeny and geographic/clinical metadata in Nicaragua. To date, this study represents the largest single collection of CHIKV complete genomes during the Caribbean/Americas epidemic and significantly expands our understanding of the emergence and evolution of CHIKV CO clade in the Americas.


Assuntos
Febre de Chikungunya/virologia , Vírus Chikungunya/isolamento & purificação , Adolescente , Ásia/epidemiologia , Febre de Chikungunya/epidemiologia , Vírus Chikungunya/classificação , Vírus Chikungunya/genética , Vírus Chikungunya/fisiologia , Criança , Pré-Escolar , Epidemias , Feminino , Variação Genética , Genoma Viral , Genótipo , Humanos , Masculino , Nicarágua/epidemiologia , Filogenia , Viagem , Estados Unidos/epidemiologia , Adulto Jovem
20.
J Am Soc Nephrol ; 29(8): 2200-2212, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29907699

RESUMO

Background Epidemic levels of CKD of undetermined cause, termed Mesoamerican nephropathy in Central America, have been found in low- and middle-income countries. We investigated the natural history of, and factors associated with, loss of kidney function in a population at high risk for this disease.Methods We conducted a 2-year prospective, longitudinal study with follow-up every 6 months in nine rural communities in northwestern Nicaragua and included all men (n=263) and a random sample of women (n=87) ages 18-30 years old without self-reported CKD, diabetes, or hypertension. We used growth mixture modeling to identify subgroups of eGFR trajectory and weighted multinomial logistic regression to examine associations with proposed risk factors.Results Among men, we identified three subpopulations of eGFR trajectory (mean baseline eGFR; mean eGFR change over follow-up): 81% remained stable (116 ml/min per 1.73 m2; -0.6 ml/min per 1.73 m2 per year), 9.5% experienced rapid decline despite normal baseline function (112 ml/min per 1.73 m2; -18.2 ml/min per 1.73 m2 per year), and 9.5% had baseline dysfunction (58 ml/min per 1.73 m2; -3.8 ml/min per 1.73 m2 per year). Among women: 96.6% remained stable (121 ml/min per 1.73 m2; -0.6 ml/min per 1.73 m2 per year), and 3.4% experienced rapid decline (132 ml/min per 1.73 m2; -14.6 ml/min per 1.73 m2 per year; n=3 women). Among men, outdoor and agricultural work and lack of shade availability during work breaks, reported at baseline, were associated with rapid decline.Conclusions Although Mesoamerican nephropathy is associated with agricultural work, other factors may also contribute to this disease.


Assuntos
Agricultura , Taxa de Filtração Glomerular/fisiologia , Exposição Ocupacional/efeitos adversos , Insuficiência Renal Crônica/diagnóstico , Insuficiência Renal Crônica/epidemiologia , Adolescente , América Central/epidemiologia , Progressão da Doença , Doenças Endêmicas , Feminino , Humanos , Incidência , Testes de Função Renal , Modelos Logísticos , Estudos Longitudinais , Masculino , Análise Multivariada , Nicarágua/epidemiologia , Estudos Prospectivos , Medição de Risco , Índice de Gravidade de Doença , Adulto Jovem
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