RESUMO

Limited dengue virus (DENV) seroprevalence estimates are available for Puerto Rico, which are needed to inform the potential use and cost-effectiveness of DENV vaccines. The Communities Organized to Prevent Arboviruses (COPA) is a cohort study initiated in 2018 in Ponce, Puerto Rico, to assess arboviral disease risk and provide a platform to evaluate interventions. We recruited participants from households in 38 study clusters, who were interviewed and provided a serum specimen. Specimens from 713 children aged 1 to 16 years during the first year of COPA were tested for the four DENV serotypes and ZIKV using a focus reduction neutralization assay. We assessed the seroprevalence of DENV and ZIKV by age and developed a catalytic model from seroprevalence and dengue surveillance data to estimate the force of infection for DENV during 2003-2018. Overall, 37% (n = 267) were seropositive for DENV; seroprevalence was 9% (11/128) among children aged 1 to 8 years and 44% (256/585) among children aged 9 to 16 years, exceeding the threshold over which DENV vaccination is deemed cost-effective. A total of 33% were seropositive for ZIKV, including 15% among children aged 0 to 8 years and 37% among children aged 9 to 16 years. The highest force of infection occurred in 2007, 2010, and 2012-2013, with low levels of transmission from 2016 to 2018. A higher proportion of children had evidence of multitypic DENV infection than expected, suggesting high heterogeneity in DENV risk in this setting.

Assuntos

Assuntos

RESUMO

Chikungunya virus (CHIKV) caused a large outbreak in Puerto Rico in 2014, followed by a Zika virus (ZIKV) outbreak in 2016. Communities Organized for the Prevention of Arboviruses (COPA) is a cohort study in southern Puerto Rico, initiated in 2018 to measure arboviral disease risk and provide a platform to evaluate interventions. To identify risk factors for infection, we assessed prevalence of previous CHIKV infection and recent ZIKV and DENV infection in a cross-sectional study among COPA participants. Participants aged 1-50 years (y) were recruited from randomly selected households in study clusters. Each participant completed an interview and provided a blood specimen, which was tested by anti-CHIKV IgG ELISA assay and anti-ZIKV and anti-DENV IgM MAC-ELISA assays. We assessed individual, household, and community factors associated with a positive result for CHIKV or ZIKV after adjusting for confounders. During 2018-2019, 4,090 participants were enrolled; 61% were female and median age was 28y (interquartile range [IQR]: 16-41). Among 4,035 participants tested for CHIKV, 1,268 (31.4%) had evidence of previous infection. CHIKV infection prevalence was lower among children 1-10 years old compared to people 11 and older (adjusted odds ratio [aOR] 2.30; 95% CI 1.71-3.08). Lower CHIKV infection prevalence was associated with home screens (aOR 0.51; 95% CI 0.42-0.61) and air conditioning (aOR 0.64; 95% CI 0.54-0.77). CHIKV infection prevalence also varied by study cluster of residence and insurance type. Few participants (16; 0.4%) had evidence of recent DENV infection by IgM. Among 4,035 participants tested for ZIKV, 651 (16%) had evidence of recent infection. Infection prevalence increased with older age, from 7% among 1-10y olds up to 19% among 41-50y olds (aOR 3.23; 95% CI 2.16-4.84). Males had an increased risk of Zika infection prevalence compared with females (aOR 1.31; 95% CI 1.09-1.57). ZIKV infection prevalence also decreased with the presence of home screens (aOR 0.66; 95% CI 0.54-0.82) and air conditioning (aOR 0.69; 95% CI 0.57-0.84). Similar infection patterns were observed for recent ZIKV infection prevalence and previous CHIKV infection prevalence by age, and the presence of screens and air conditioners in the home decreased infection risk from both viruses by as much as 50%.

Assuntos

RESUMO

The diagnosis of dengue disease, caused by the dengue virus (DENV) (a flavivirus), often requires serologic testing during acute and early convalescent phases of the disease. Some symptoms of DENV infection, such as nonspecific fever, are similar to those caused by infection with SARS-CoV-2, the virus that causes COVID-19. In studies with few COVID-19 cases, positive DENV immunoglobulin M (IgM) results were reported with various serologic tests, indicating possible cross-reactivity in these tests for DENV and SARS-CoV-2 infections (1,2). DENV antibodies can cross-react with other flaviviruses, including Zika virus. To assess the potential cross-reactivity of SARS-CoV-2, DENV, and Zika virus IgM antibodies, serum specimens from 97 patients from Puerto Rico and 12 U.S.-based patients with confirmed COVID-19 were tested using the DENV Detect IgM Capture enzyme-linked immunosorbent assay (ELISA) (InBios International).* In addition, 122 serum specimens from patients with confirmed dengue and 121 from patients with confirmed Zika virus disease (all from Puerto Rico) were tested using the SARS-CoV-2 pan-Ig Spike Protein ELISA (CDC).† Results obtained for DENV, Zika virus IgM, and SARS-CoV-2 antibodies indicated 98% test specificity and minimal levels of cross-reactivity between the two flaviviruses and SARS-CoV-2. These findings indicate that diagnoses of dengue or Zika virus diseases with the serological assays described in this report are not affected by COVID-19, nor do dengue or Zika virus diseases interfere with the diagnosis of COVID-19.

Assuntos

RESUMO

Serological cross-reactivity has proved to be a challenge to diagnose Zika virus (ZIKV) infections in dengue virus (DENV) endemic countries. Confirmatory testing of ZIKV IgM positive results by plaque reduction neutralization tests (PRNTs) provides clarification in only a minority of cases because most individuals infected with ZIKV were previously exposed to DENV. The goal of this study was to evaluate the performance of a ZIKV/DENV DUO IgM antibody capture ELISA (MAC-ELISA) for discriminating between DENV and ZIKV infections in endemic regions. Our performance evaluation included acute and convalescent specimens from patients with real-time reverse transcription polymerase chain reaction (RT-PCR)-confirmed DENV or ZIKV from the Sentinel Enhanced Dengue Surveillance System in Ponce, Puerto Rico. The ZIKV/DENV DUO MAC-ELISA specificity was 100% for DENV (N = 127) and 98.4% for ZIKV (N = 275) when specimens were tested during the optimal testing window (days post-onset of illness [DPO] 6-120). The ZIKV/DENV DUO MAC-ELISA sensitivity of RT-PCR confirmed specimens reached 100% for DENV by DPO 6 and for ZIKV by DPO 9. Our new ZIKV/DENV DUO MAC-ELISA was also able to distinguish ZIKV and DENV regardless of previous DENV exposure. We conclude this novel serologic diagnostic assay can accurately discriminate ZIKV and DENV infections. This can potentially be useful considering that the more labor-intensive and expensive PRNT assay may not be an option for confirmatory diagnosis in areas that lack PRNT capacity, but experience circulation of both DENV and ZIKV.

Assuntos

RESUMO

Dengue is an ongoing health risk for Peace Corps Volunteers (PCVs) working in the tropics. On May 2019, the Peace Corps Office of Health Services notified the Centers for Disease Control and Prevention (CDC) of a dengue outbreak among PCVs in Timor-Leste. The purpose of this investigation was to identify the clinical, demographic, and epidemiological characteristics of PCVs with dengue and recommend dengue preventive measures. To identify PCVs with dengue and describe disease severity, the medical records of PCVs reporting fever during September 2018-June 2019 were reviewed. To identify factors associated with dengue virus (DENV) infection, we administered a questionnaire on demographics, travel history, and mosquito avoidance behaviors and collected blood specimens to detect the anti-DENV IgM antibody to diagnose recent infection. Of 35 PCVs in-country, 11 (31%) tested positive for dengue (NS1, IgM, PCR), eight requiring hospitalization and medical evacuation. Among 27 (77%) PCVs who participated in the investigation, all reported having been recently bitten by mosquitoes and 56% reported being bitten most often at home; only 16 (59%) reported having screens on bedroom windows. Nearly all (93%) PCVs reported using a bed net every night; fewer (70%) reported using mosquito repellent at least once a day. No behaviors were significantly associated with DENV infection. Raising awareness of dengue risk among PCVs and continuing to encourage mosquito avoidance behavior to prevent dengue is critical. Access to and use of measures to avoid mosquito bites should be improved or implemented. Peace Corps medical officers should continue to receive an annual refresher training on dengue clinical management.

Assuntos

RESUMO

We evaluated nucleic acid amplification testing (NAAT) for Zika virus on whole-blood specimens compared with NAAT on serum and urine specimens among asymptomatic pregnant women during the 2015-2016 Puerto Rico Zika outbreak. Using NAAT, more infections were detected in serum and urine than in whole blood specimens.

Assuntos

RESUMO

Zika virus (ZIKV) has recently caused a large epidemic in the Americas that is associated with birth defects. Although ZIKV is primarily transmitted by Aedes mosquitoes, ZIKV RNA is detectable in blood and semen of infected individuals for weeks or months, during which sexual and other modes of transmission are possible. However, viral RNA is usually detectable longer than infectious virus is present. We determined the frequency of isolation of infectious virus from semen and serum samples prospectively obtained from a cohort of patients in Puerto Rico. We confirmed isolation of infectious virus on the basis of a tissue culture cytopathic effect, an increase in virus genome copy equivalents (GCE), and positive results of immunofluorescence analysis; virus in infected cells was quantitated by flow cytometry. These criteria confirmed the presence of infectious virus in semen specimens from 8 of 97 patients for up to 38 days after initial detection when virus loads are >1.4 × 106 genome copy equivalents/mL. Two serum isolates were obtained from 296 patients. These findings can help guide important prevention guidelines for persons that may potentially be infectious and transmit ZIKV sexually.

Assuntos

RESUMO

Dengue is a disease caused by infection with one of the four dengue virus serotypes (DENV-1, -2, -3, and -4). The virus is transmitted to humans by Aedes sp. mosquitoes. This enveloped virus contains a positive single-stranded RNA genome. Clinical manifestations of dengue can have a wide range of outcomes varying from a mild febrile illness to a life-threatening condition. New techniques have largely replaced the use of DENV isolation in disease diagnosis. However, virus isolation still serves as the gold standard for detection and serotyping of DENV and is common practice in research and reference laboratories where clinical isolates of the virus are characterized and sequenced, or used for a variety of research experiments. Isolation of DENV from clinical samples can be achieved in mammalian and mosquito cells or by inoculation of mosquitoes. The experimental methods presented here describe the most common procedures used for the isolation, serotyping, propagation, and quantification of DENV.

Assuntos

Assuntos

RESUMO

Se presentan 9 casos de traumas raquimedulares que ingresaron al Hospital de Niños J.M. de los Ríos de Caracas entre los años de 1982 inclusive. la edad de consulta osciló entre 11 meses y 10 años, encontrándose la mayoría debajo de los 5 años de edad. Habían 4 masculinos y 3 femeninos. Tres casos se debieron a arrollamientos de automóviles, 2 casos a caída de cuna, 1 caso por lesión contundente en región cervical y un caso de un niño maltratado por intento de violación. Dos casos de arrollamientos severos presentaron lesiones extraneurológicas, tipo fractura de cráneo, hematomas subdurales, uno de ellos murió por bronconeumonía bilatel y coagulopatía de consumo. Los niveles clínicos estuvieron todos por debajo de D10 y uno solo fue D4. Tres casos fueron intervenidos quirurgicamente con buena evolución y los 3 restantes permanecieron iguales. Se subraya la diferencia entre trauma primario medular y secundario. Se enfatiza la inmovilización de estos pacientes y los inconscientes hasta el diagnóstico. La tomografía computada espinal añade una buena ayuda al diagnóstico

Assuntos

RESUMO

Los autores exponen su experiencia en pacientes en edad pediátrica con hemorragia intracraneana, en un período comprendido entre 1980 a 1984, en el Servicio de Neurocirugía del Hospital de Niños "J.M de los Rios", de Caracas, Venezuela. Se presentan 25 casos; la serie incluye 20 con traumatismo cráneo-encefálico, 4 casos de similar etiología, asociados a enfermedad hematológica de base (hemofilia), 3 casos de malformaciones arteriovenosas y 2 pacientes con hemorragia espontánea. La edad de presentación fue entre 3 meses y 12 años de vida. Al 76% (19) de los pacientes se les practicó intervención quirúrgica, con una mortalidad del 10.5% (2 casos). Se revisa la literatura en relación a este problema

Assuntos

RESUMO

Se presentan 9 casos de traumas requimedulares que ingresaron al hospital de Niños J.M. de Los Ríos de Caracas entre los años de 1980 a 1982 inclusive. La edad de consulta osciló entre 11 meses y 10 años, encontrándose la mayoría debajo de los 5 años de edad. Habían 4 masculinos y 3 femeninos. Tres casos se debieron a arrollamiento de automoviles, 2 casos a caída de cuna, 1 caso por lesión contundente en región cervical y un caso de un niño maltratado por intento de violación. Dos casos de arollamientos severos presentaron lesiones extraneurológicas, tipo fractura de cráneo, hematomas subdurales, uno de ellos murió por bronconeumonía bilateral y coagulopatía de consumo. Los niveles clínicos estuvieron todos por debajo de D10 y uno sólo fue D4. Tres casos fueron intervenidos quirúrgicamente con buena evolución y los 3 restantes permanecieron iguales. Se subraya la diferencia entre trauma primario medular y secundario. Se enfatiza la inmovilización de estos pacientes y los inconscientes hasta el diagnóstico. La tomografía computada espinal añade una buena ayuda al diagnóstico

Assuntos

RESUMO

Loa autores exponen su experiencia en pacientes en edad pediátrica con hemorragia intracraneana, en un período comprendido entre 1980 a 1984, en el servicio de neurocirugía del Hospital de Niños: J.M. de los Ríos, de Caracas, Venezuela. Se presentan 25 casos; la serie incluye 20 con traumatismos cráneo-encefálico, 4 casos de similar etiología, asociados a enfermedad hematológica de base (hemofilia), 3 casos de malformaciones arteriovenosas y 2 pacientes con hemorragia espontánea. La edad de presentación fue entre 3 meses y 12 años de vida..

Assuntos

RESUMO

Se presentan once (11) casos de niños con diagnóstico de escafocefalia, en los cuales se practicó la nueva técnica neuroquirúrgica de craniectomía rectangular del vertex, desde noviembre de 1982 a marzo de 1984 (16 meses) con resultados satisfactorios hasta este momento. La edad osciló entre 5 meses y 18 meses. Del sexo masculino fueron ocho (8) pacientes y femenino tres (3) pacientes. Hubo inicio de regeneración osea a las ocho (8) semanas con mejor remodelación craneal y supresión de la hipertensión endocraneal

Assuntos