Social Network–Based Recruitment Successfully Reveals HIV-1 Transmission Networks Among High-Risk Individuals in El Salvador

HIV in Central America is concentrated among certain groups such as men who have sex with men (MSM) and female sex workers (FSW). We compared social recruitment chains and HIV transmission clusters from 699 MSM and 757 FSW to better understand factors contributing to ongoing HIV transmission in El Salvador

Circulating Strains of Human Respiratory Syncytial Virus in Central and South America

Human respiratory syncytial virus (HRSV) is a major cause of viral lower respiratory tract infections among infants and young children. HRSV strains vary genetically and antigenically and have been classified into two broad subgroups, A and B (HRSV-A and HRSV-B, respectively). To date, little is known about the circulating strains of HRSV in Latin America. We have evaluated the genetic diversity of 96 HRSV strains by sequencing a variable region of the G protein gene of isolates collected from 2007 to 2009 in Central and South America. Our results show the presence of the two antigenic subgroups of HRSV during this period with the majority belonging to the genotype HRSV-A2

FcyRIIA-131 asociado a casos severos de dengue en Honduras

Dengue is a disease of worldwide importance. To understand more about the pathogenesis of dengue the interest in the search for genetic factors in the host has recently increased. We investigated whether single nucleotide polymorphisms (SNPs) in genes coding for DC-SIGN, Fc receptor (FcyRIIA) and vitamin D receptor (VDR) are associated with severe dengue and whether in this study group the severity of dengue is associated with secondary infections. A total of 200 cases of dengue patients were investigated in Tegucigalpa, Honduras, 100 cases of classic dengue and 100 cases of dengue hemorrhagic classified according to 2007 WHO criteria. Genotyping was performed using PCR-RFLP and additionally this technique was compare to the ¡PLEX assay (SEQUENOM ® Inc. USA). A significantly increased risk of severe disease was observed in FcyRIIA in carriers of genotype CC versus TC (Chi2 = 5.29, P = 0.02, OR = 2.22). The G allele variant of the DC-SIGN1-336 was not associated with severe dengue disease. The VDR genotype frequency of CC genotype compared whit CT scan shows a tendency to increase in severe forms compared to mild forms of the disease (Chi2= 3.36, P= 0.06, OR= 0.35). These preliminary data provide new insights into the role of genetic factors in dengue; knowledge of more SNPs associated with dengue will provide information on possible mechanisms of pathogenesis and protection. DOI: http://dx.doi.org/10.5377/rct.v0i13.1714 Revista Ciencia y Tecnología, No. 13, diciembre 2013: 67-80El dengue es una enfermedad de importancia a nivel mundial, por eso recientemente se ha incrementado el interés en buscar los factores genéticos en el huésped asociado a la severidad de la enfermedad, para poder entender más sobre la patogénesis del dengue. Se investigó si polimorfismos de nucleótido simple (SNP) en genes que codifican para DC-SIGN1-336, el receptor Fc (FcyRIIA) y el receptor de la vitamina D (VDR), están asociados con el dengue severo y si en el grupo de estudio la severidad del dengue se asocia a las infecciones secundarias. Para esta investigación se estudió a un total de 200 participantes con dengue, quienes fueron investigados en Tegucigalpa; 100 casos de dengue clásico y 100 de dengue hemorrágico, clasificados de acuerdo a los criterios de la OMS 2007. La genotipificación se realizó utilizando PCR RFLP comparado con el ensayo iPLEX (SEQUENOM ® Inc. EE.UU.). Un aumento significativo de riesgo de enfermedad severa se observó en FcyRIIA-131, en los portadores de los genotipos CC versus TC (Chi2 = 5.29, P = 0.02, OR = 2.22). El alelo G de la variante DC-SIGN-336 no se asoció con dengue severo, para el VDR-352 la frecuencia del genotipo CC en comparación con el TC muestra una tendencia a aumentar en las formas severas respecto a las formas leves de la enfermedad (Chi2 = 3.36, P = 0.06, OR =0.35). Estos datos preliminares aportan nuevos conocimientos sobre el papel de los factores genéticos en el dengue; el conocimiento de estos SNP asociados con dengue proporcionará información sobre los posibles mecanismos de la patogénesis y protección. DOI: http://dx.doi.org/10.5377/rct.v0i13.1714 Revista Ciencia y Tecnología, No. 13, diciembre 2013: 67-8

Resistencia del VIH en mujeres embarazadas de Honduras durante el año 2015

Antiretroviral therapy (ART) in pregnant women has contributed to the prevention of HIV transmission from mother to child. However, the development of HIV-1 resistance to antiretroviral therapy is a serious problem, which can reduce the efficacy of treatment in pregnant women, generating a risk of transmission from mother to child and also generating impact on the clinical management of pregnant women or children who become infected.This study determined the presence of resistance in HIV-1 positive pregnant women (receiving ARV) who live in Tegucigalpa and San Pedro Sula during the year 2015. A total of 63 participants were tested and 35 of them obtained a successful HIV-1 pol gene amplification to evaluate the presence of resistance mutations.Quantification of viral load and CD4 count was performed on all participants. The overall prevalence of resistance was 17%. Of all the participants, 62% had detectable viral load and 16% had cell counts ≤200 cells / mm3. The prevalence of resistance, viremia and low cell counts indicated that there could be a risk of vertical transmission in this cohort.This study provides current data on the prevalence of resistance to antiretroviral therapy in HIV-1 positive pregnant Honduran women. The study reflects the need for routine and permanent tests, viral load and CD4 count, in order to support the prevention of HIV-1 transmission to the mother and child.  El tratamiento antirretroviral (TARV) en mujeres embarazadas ha contribuido a la prevención de la transmisión del VIH de madre a hijo. Sin embargo, el desarrollo de resistencia del VIH-1 a la TARV es un problema latente y puede reducir la eficacia del tratamiento en las mujeres embarazadas, generar un riesgo de transmisión de madre a hijo e impactar el manejo clínico de las mujeres embarazadas o de los niños que resulten infectados.Este estudio determinó la presencia de resistencia en mujeres embarazadas VIH-1 positivo (recibiendo TARV) de Tegucigalpa y San Pedro Sula durante el año 2015. Un total de 63 participantes fueron analizadas y en 35 de ellas se obtuvo amplificación exitosa del gen pol del VIH-1 para evaluar la presencia de mutaciones asociadas a resistencia.La cuantificación de carga viral y conteo de CD4 fue realizado a todas las participantes. La prevalencia global de resistencia fue del 17 %. Un 62 % de las participantes presentaron carga viral detectable y en el 16 % recuentos celulares ≤200 celulas/ mm3. La prevalencia de resistencia, la viremia y bajos recuentos celulares indican que podría existir un riesgo de transmisión vertical en esta cohorte.Este estudio proporciona datos actuales sobre la prevalencia de la resistencia a la TARV en población femenina embarazada VIH-1 positivo de Honduras y refleja la necesidad de realizar de forma rutinaria y permanente pruebas de resistencia, carga viral y conteo de CD4, con el fin de apoyar en la prevención de la tramision del VIH-1 en el binomio madre-hijo.

Prevalencia de la resistencia genotípica a los fármacos antirretrovirales en pacientes VIH positivos de Tegucigalpa

The objective of this study was to determine the prevalence of HIV drug-resistance in treated and untreated patients. One-hundred samples of HIV-positive patients of Tegucigalpa were analyzed, 50 samples from patients prior to antiretroviral therapy and 50 samples from patients on antiretroviral therapy with treatment failure.HIV-1 pol sequences were generated to determine the presence of drug resistance mutations using the Stanford calibrated population resistance tool according to the WHO Surveillance Drug Resistance Mutations for untreated patients and the Stanford Database list of mutations for treated patients.The results shows that drug-resistance mutation prevalence in patients before treatment initiation was 19 % [IC 95 %: 9-33%], 8.3 % for NRTI, 12.5 % for NNRTI and 6.25 % for PI; the most common mutation founded were: M184V, K103N, M46I. The prevalence of drug-resistance mutations in patients on therapy was 82 % [IC 95 %:60-90%], 58 % for NRTI, 74 % for NNRTI, and 22 % for PI.In conclusions, we observed a significance increase in the prevalence of drug-resistance mutations in untreated patients compared with previous studies, which is of great concern because it limits the effectiveness of first-line treatment. Although the prevalence of acquired resistance in patients with therapeutic failure remains slightly constant remains high, requiring treatment changes to second or third line in these patients, causing an economic impact on public health.Revista Ciencia y Tecnología, N° 15, December 2014: 147-160El objetivo de la investigación fue determinar la prevalencia de resistencia del VIH a las drogas antirretrovirales en pacientes tratados y no tratados. Para tal efecto, se analizaron 100 muestras de pacientes VIH positivos, 50 previos a iniciar tratamiento y 50 bajo tratamiento con evidencia de falla terapéutica, de Tegucigalpa.Secuencias del gen pol del VIH-1 fueron generadas para determinar la presencia de mutaciones asociadas a resistencia, utilizando la herramienta calibrada para la vigilancia de la resistencia propuesta por la OMS para pacientes pretratados y la lista de mutaciones de la base de datos de Stanford para pacientes bajo tratamiento.Los resultados muestran que la prevalencia de farmacorresistencia en pacientes previos a iniciar tratamiento fue del 19 % [IC 95 %: 9-33 %], el 8.3 % presentaron mutaciones contra los NRTI, el 12.5 % contra los NNRTI y el 6.25 % contra los PI. Las mutaciones con mayor frecuencia fueron: M184V, K103N, M46I. La prevalencia de mutaciones asociadas a resistencia en los pacientes en falla terapéutica fue del 82 % [IC 95 %:60-90 %], el 58 % contra los NRTI, 74 % contra los NNRTI y el 22 % contra los PI.En conclusión, se observó un marcado aumento en la prevalencia de mutaciones asociadas a resistencia en pacientes no tratados, comparada con estudios anteriores, lo cual es de mucha preocupación, ya que limita la eficacia del tratamiento de primera línea. Aunque la prevalencia de resistencia adquirida en pacientes con falla terapéutica se mantiene ligeramente constante, sigue siendo alta, requiriendo de cambios de tratamiento a segunda o tercera línea en estos pacientes, ocasionando un impacto económico en la salud pública.Revista Ciencia y Tecnología, N° 15, diciembre 2014: 147-16

A single early introduction of HIV-1 subtype b into central america accounts for most current cases

Human immunodeficiency virus type 1 (HIV-1) variants show considerable geographical separation across the world, but there is limited information from Central America. We provide the first detailed investigation of the genetic diversity and molecular epidemiology of HIV-1 in six Central American countries. Phylogenetic analysis was performed on 625 HIV-1 pol gene sequences collected between 2002 and 2010 in Honduras, El Salvador, Nicaragua, Costa Rica, Panama, and Belize. Published sequences from neighboring countries (n = 57) and the rest of the world (n = 740) were included as controls. Maximum likelihood methods were used to explore phylogenetic relationships. Bayesian coalescence-based methods were used to time HIV-1 introductions. Nearly all (98.9%) Central American sequences were of subtype B. Phylogenetic analysis revealed that 437 (70%) sequences clustered within five significantly supported monophyletic clades formed essentially by Central American sequences. One clade contained 386 (62%) sequences from all six countries; the other four clades were smaller and more country specific, suggesting discrete subepidemics. The existence of one large well-supported Central American clade provides evidence that a single introduction of HIV-1 subtype B in Central America accounts for most current cases. An introduction during the early phase of the HIV-1 pandemic may explain its epidemiological success. Moreover, the smaller clades suggest a subsequent regional spread related to specific transmission networks within each country

Genetic Analysis of Influenza A/H1N1 of Swine Origin Virus (SOIV) Circulating in Central and South America

Since the first detection of swine origin virus (SOIV) on March 28, 2009, the virus has spread worldwide and oseltamivir-resistant strains have already been identified in the past months. Here, we show the phylogenetic analysis of 63 SOIV isolates from eight countries in Central and South America, and their sensitivity to oseltamivir