Seroprevalencia de anticuerpos a virus del sarampión, rubeola, parotiditis, hepatitis B y los tres serotipos de poliovirus, en niños de Quindío, Colombia

bjetivo Determinar la seroprevalencia de anticuerpos a virus de sarampión, rubeola, parotiditis, hepatitis B y los tres serotipos de poliovirus en población infantil del Departamento del Quindío, Colombia.Métodos Se colectaron muestras de sangre de 170 niños en edades comprendidas entre los cinco y nueve años de  nueve departamentos del Quindío. Se determinó la presencia de anticuerpos tipo IgG para sarampión, rubeola y parotiditis  mediante un ELISA indirecto comercial. La inmunidad contra la poliomielitis se determinó por la presencia de anticuerpos neutralizantes a poliovirus según los métodos recomendados por OMS.Resultados De los 170 niños estudiados, 169 (99,41 %), 170 (100 %), and 167 (98,2 %) fueron seropositivos a  poliovirus 1, poliovirus 2, y poliovirus 3, respectivamente. El título promedio geométrico de anticuerpos fue 178 para poliovirus tipo 1, 120 para el tipo 2 y 56 para el tipo 3. De los 170 niños, el 96,47 % estuvo protegido contra parotiditis y rubeola y el 86,47 % contra sarampión. Se demostró respuesta serológica positiva contra el virus de la  hepatitis B solamente en el 62,35 % de las muestras.Conclusiones El programa de inmunización en el Quindío permitió la seroprotección contra los tres serotipos de la polio, rubeola y parotiditis. Sin embargo, la población infantil no está completamente protegida contra la infección con sarampión y virus  de la hepatitis B

Detección de hepatitis B oculta en donantes de bancos sangre, Colombia 2008-2009

Introduction. In Colombian blood banks, screening for the surface antigen of hepatitis B is mandatory in all units collected. Testing of antibody against core antigens is not administered, although this method may be useful to detect donors infected with the hepatitis B virus.Objective. The prevalence of occult hepatitis B was determined by applying a full-serological profile of hepatitis B virus to blood samples of blood donors.Materials and methods. Between April 2008 and October 2009, a prospective cross sectional study was conducted using 628 samples from donors to blood banks located in four Colombian cities.Prevalence for hepatitis B had been previously recorded for these cities. Serological screening was performed for the complete virus; then nucleic acid amplification was tested in sera that were anti-HBc reactive and with a titer of anti-HBs ≤30 mUI/ml.Results. Of the 628 samples tested, 129 met the serological criteria established to be tested nucleic acid amplification. None of them demonstrated evidence of nucleic acid amplification of hepatitis B virus.Conclusions. This is the first study in Colombia to detect the presence of blood donors that may be occult hepatitis B carriers. None was detected.Introducción. En los bancos de sangre colombianos es obligatoria la tamización para el antígeno desuperficie de la hepatitis B en todas las unidades recolectadas, mientras que no lo es para el anticuerpocontra el antígeno central, aunque este último puede ser útil para detectar donantes infectados con elvirus de hepatitis B.Objetivo. Determinar la prevalencia de hepatitis B oculta, mediante la aplicación de un perfil serológicocompleto para el virus de la hepatitis B y pruebas de amplificación de ácidos nucleicos, en donantes desangre de cuatro ciudades colombianas.Materiales y métodos. Entre abril de 2008 y octubre de 2009 se llevó a cabo un estudio prospectivotransversal que incluyó 628 muestras de donantes de cuatro bancos de sangre, ubicados en ciudadescolombianas que registran distintas prevalencias para infección por el virus de la hepatitis B. Se hizola tamización serológica completa para el virus y, posteriormente, pruebas de amplificación de ácidosnucleicos a los sueros con anti-HBc total reactivo y título de anti-HBs ≤30 mUI/ml.Resultados. En total, 129 muestras cumplieron con los criterios serológicos establecidos para sersometidas a pruebas de amplificación de ácidos nucleicos. En ninguna de ellas se obtuvo amplificaciónde ácidos nucleicos del virus de la hepatitis B.Conclusiones. Éste es el primer estudio en Colombia que busca determinar la presencia de donantesde sangre portadores de hepatitis B oculta. No se documentó ningún caso de infección oculta en elestudio

Diagnosis of fungal opportunistic infections in HIV/AIDS patients : a cases study in Colombia

Objetivos. Identificar las micosis oportunistas que afectan a los pacientes con VIH/sida, y determinar sus características demográficas, socioeconó-micas y su relación con el número de células T CD4+.Métodos. Se trata de un estudio descriptivo de serie de casos basado en los participantes de un estudio diseñado para determinar el tipo y la frecuencia de las enfermedades oportunistas en pacientes con VIH/sida. Un caso se definió como un paciente con VIH/sida a quien se le diagnosticó una micosis oportunista, entre octubre de 2007 y mayo de 2010. Los pacientes elegibles estaban siendo tratados en dos instituciones médicas de Bogotá. Se recolectaron muestras respiratorias, de líquido cefalorraquí-deo, de sangre y de raspado de lesión orofaríngea, para determinar la presencia de Histoplasma capsulatum, Paracoccidioides brasiliensis, Cryptococ-cus neoformans o Candida spp. Se utilizaron proporciones para resumir las variables cualitativas y medianas para las cuantitativas.Resultados. En 33 (9,8 %) pacientes con VIH/sida del estudio base (n=336), se diagnosticó una o más de las micosis evaluadas. El 75 % tenía entre 23 y 42 años. La frecuencia de estas infecciones fueron: H. capsulatum (n=1; 3,0 %), P. brasiliensis (n=1; 3,0 %), C. neoformans (n=25; 75,8 %), y Cándida spp. (n=7; 21,2 %). Los valores medianos de células T CD4+ fueron de 176 o menos, independientemente de sus manifestaciones clínicas. Conclusión. Se necesitan estudios adicionales para identificar los factores que podrían estar determinando la presencia de las micosis oportunistas en estos pacientes.Q3Comunicación breve92-97Objectives: To identify the opportunistic fungal infections affecting patients with HIV/AIDS, to determine their demographic and socioeconomic characteristics and the number of CD4+ T cells.Materials and methods: This is a descriptive case series study based on a major study aimed at determining the type and frequency of opportu-nistic diseases in HIV/AIDS patients. A case was defined as an HIV/AIDS patient who had evidence of fungal infection at baseline. Eligible patients were being treated at two clinical institutions located in Bogotá, Colombia, between October 2007 and May 2010. Respiratory, cerebrospinal fluid and blood samples and scrapping/swabs of oral lesions were collected in order to determine the presence of Histoplasma capsulatum, Paracocci-dioides brasiliensis, Cryptococcus neoformans or Candida spp. Proportions were used for qualitative variables and medians for quantitative variables. Results: Overall, 33 (10,2%) patients were diagnosed as having one or more of the evaluated fungal infections , out of 336. Seventy five per cent of them were between the ages of 23 and 42. The frequencies of these fungal infections were: H. capsulatum (n=1; 3.0%), P. brasiliensis (n=1; 3.0%), C. neoformans(n=25; 75.8%), and Candida spp. (n=7; 21.2%). The median values of CD4+ T cells were 176 or less, independently of clinical manifestations. Conclusion: Further studies are required to identify factors contributing to the presence of fungal opportunistic infections in these patients

Evaluation of the World Health Organization Global Invasive Bacterial Vaccine-Preventable Disease (IB-VPD) Surveillance Network's Laboratory External Quality Assessment Programme, 2014-2019

Introduction. In 2009, the World Health Organization (WHO) established the Global Invasive Bacterial Vaccine Preventable Disease (IB-VPD) Surveillance Network (GISN) to monitor the global burden and aetiology of bacterial meningitis, pneumonia and sepsis caused by Haemophilus influenzae (Hi), Neisseria meningitidis (Nm) and Streptococcus pneumoniae (Sp).Hypothesis/Gap Statement. The GISN established an external quality assessment (EQA) programme for the characterization of Hi, Nm and Sp by culture and diagnostic PCR.Aim. To assess the performance of sentinel site laboratories (SSLs), national laboratories (NLs) and regional reference laboratories (RRLs) between 2014 and 2019 in the EQA programme.Methodology. Test samples consisted of bacterial smears for Gram-staining, viable isolates for identification and serotyping or serogrouping (ST/SG), plus simulated cerebrospinal fluid (CSF) samples for species detection and ST/SG by PCR. SSLs and NLs were only required to analyse the slides for Gram staining and identify the species of the live isolates. RRLs, and any SLs and NLs that had the additional laboratory capacity, were also required to ST/SG the viable isolates and analyse the simulated CSF samples.Results. Across the period, 69-112 SS/NL labs and eight or nine RRLs participated in the EQA exercise. Most participants correctly identified Nm and Sp in Gram-stained smears but were less successful with Hi and other species. SSLs/NLs identified the Hi, Nm and Sp cultures well and also submitted up to 56 % of Hi, 62 % of Nm and 33 % of Sp optional ST/SG results each year. There was an increasing trend in the proportion of correct results submitted over the 6 years for Nm and Sp. Some SSLs/NLs also performed the optional detection and ST/SG of the three organisms by PCR in simulated CSF from 2015 onwards; 89-100 % of the CSF samples were correctly identified and 76-93 % of Hi-, 90-100 % of Nm- and 75-100 % of Sp-positive samples were also correctly ST/SG across the distributions. The RRLs performed all parts of the EQA to a very high standard, with very few errors across all aspects of the EQA.Conclusion. The EQA has been an important tool in maintaining high standards of laboratory testing and building of laboratory capacity in the GISN

An RNAi in silico approach to find an optimal shRNA cocktail against HIV-1

<p>Abstract</p> <p>Background</p> <p>HIV-1 can be inhibited by RNA interference <it>in vitro </it>through the expression of short hairpin RNAs (shRNAs) that target conserved genome sequences. <it>In silico </it>shRNA design for HIV has lacked a detailed study of virus variability constituting a possible breaking point in a clinical setting. We designed shRNAs against HIV-1 considering the variability observed in naïve and drug-resistant isolates available at public databases.</p> <p>Methods</p> <p>A Bioperl-based algorithm was developed to automatically scan multiple sequence alignments of HIV, while evaluating the possibility of identifying dominant and subdominant viral variants that could be used as efficient silencing molecules. Student t-test and Bonferroni Dunn correction test were used to assess statistical significance of our findings.</p> <p>Results</p> <p>Our <it>in silico </it>approach identified the most common viral variants within highly conserved genome regions, with a calculated free energy of ≥ -6.6 kcal/mol. This is crucial for strand loading to RISC complex and for a predicted silencing efficiency score, which could be used in combination for achieving over 90% silencing. Resistant and naïve isolate variability revealed that the most frequent shRNA per region targets a maximum of 85% of viral sequences. Adding more divergent sequences maintained this percentage. Specific sequence features that have been found to be related with higher silencing efficiency were hardly accomplished in conserved regions, even when lower entropy values correlated with better scores. We identified a conserved region among most HIV-1 genomes, which meets as many sequence features for efficient silencing.</p> <p>Conclusions</p> <p>HIV-1 variability is an obstacle to achieving absolute silencing using shRNAs designed against a consensus sequence, mainly because there are many functional viral variants. Our shRNA cocktail could be truly effective at silencing dominant and subdominant naïve viral variants. Additionally, resistant isolates might be targeted under specific antiretroviral selective pressure, but in both cases these should be tested exhaustively prior to clinical use.</p

Prolonged Excretion of Poliovirus among Individuals with Primary Immunodeficiency Disorder: An Analysis of the World Health Organization Registry

Individuals with primary immunodeficiency disorder may excrete poliovirus for extended periods and will constitute the only remaining reservoir of virus after eradication and withdrawal of oral poliovirus vaccine. Here, we analyzed the epidemiology of prolonged and chronic immunodeficiency-related vaccine-derived poliovirus cases in a registry maintained by the World Health Organization, to identify risk factors and determine the length of excretion. Between 1962 and 2016, there were 101 cases, with 94/101 (93%) prolonged excretors and 7/101 (7%) chronic excretors. We documented an increase in incidence in recent decades, with a shift toward middle-income countries, and a predominance of poliovirus type 2 in 73/101 (72%) cases. The median length of excretion was 1.3 years (95% confidence interval: 1.0, 1.4) and 90% of individuals stopped excreting after 3.7 years. Common variable immunodeficiency syndrome and residence in high-income countries were risk factors for long-term excretion. The changing epidemiology of cases, manifested by the greater incidence in recent decades and a shift to from high- to middle-income countries, highlights the expanding risk of poliovirus transmission after oral poliovirus vaccine cessation. To better quantify and reduce this risk, more sensitive surveillance and effective antiviral therapies are needed

Aetiology and incidence of diarrhoea requiring hospitalisation in children under 5 years of age in 28 low-income and middle-income countries: findings from the Global Pediatric Diarrhea Surveillance network.

Introduction: Diarrhoea remains a leading cause of child morbidity and mortality. Systematically collected and analysed data on the aetiology of hospitalised diarrhoea in low-income and middle-income countries are needed to prioritise interventions. Methods: We established the Global Pediatric Diarrhea Surveillance network, in which children under 5 years hospitalised with diarrhoea were enrolled at 33 sentinel surveillance hospitals in 28 low-income and middle-income countries. Randomly selected stool specimens were tested by quantitative PCR for 16 causes of diarrhoea. We estimated pathogen-specific attributable burdens of diarrhoeal hospitalisations and deaths. We incorporated country-level incidence to estimate the number of pathogen-specific deaths on a global scale. Results: During 2017–2018, 29 502 diarrhoea hospitalisations were enrolled, of which 5465 were randomly selected and tested. Rotavirus was the leading cause of diarrhoea requiring hospitalisation (attributable fraction (AF) 33.3%; 95% CI 27.7 to 40.3), followed by Shigella (9.7%; 95% CI 7.7 to 11.6), norovirus (6.5%; 95% CI 5.4 to 7.6) and adenovirus 40/41 (5.5%; 95% CI 4.4 to 6.7). Rotavirus was the leading cause of hospitalised diarrhoea in all regions except the Americas, where the leading aetiologies were Shigella (19.2%; 95% CI 11.4 to 28.1) and norovirus (22.2%; 95% CI 17.5 to 27.9) in Central and South America, respectively. The proportion of hospitalisations attributable to rotavirus was approximately 50% lower in sites that had introduced rotavirus vaccine (AF 20.8%; 95% CI 18.0 to 24.1) compared with sites that had not (42.1%; 95% CI 33.2 to 53.4). Globally, we estimated 208 009 annual rotavirus-attributable deaths (95% CI 169 561 to 259 216), 62 853 Shigella-attributable deaths (95% CI 48 656 to 78 805), 36 922 adenovirus 40/41-attributable deaths (95% CI 28 469 to 46 672) and 35 914 norovirus-attributable deaths (95% CI 27 258 to 46 516). Conclusions: Despite the substantial impact of rotavirus vaccine introduction, rotavirus remained the leading cause of paediatric diarrhoea hospitalisations. Improving the efficacy and coverage of rotavirus vaccination and prioritising interventions against Shigella, norovirus and adenovirus could further reduce diarrhoea morbidity and mortality

The Global Landscape of Pediatric Bacterial Meningitis Data Reported to the World Health Organization-Coordinated Invasive Bacterial Vaccine-Preventable Disease Surveillance Network, 2014-2019.

BACKGROUND: The World Health Organization (WHO) coordinates the Global Invasive Bacterial Vaccine-Preventable Diseases (IB-VPD) Surveillance Network to support vaccine introduction decisions and use. The network was established to strengthen surveillance and laboratory confirmation of meningitis caused by Streptococcus pneumoniae, Haemophilus influenzae, and Neisseria meningitidis. METHODS: Sentinel hospitals report cases of children 137 000 suspected meningitis cases were reported by 58 participating countries, with 44.6% (n = 61 386) reported from countries in the WHO African Region. More than half (56.6%, n = 77 873) were among children <1 year of age, and 4.0% (n = 4010) died among those with reported disease outcome. Among suspected meningitis cases, 8.6% (n = 11 798) were classified as probable bacterial meningitis. One of 3 bacterial pathogens was identified in 30.3% (n = 3576) of these cases, namely S. pneumoniae (n = 2177 [60.9%]), H. influenzae (n = 633 [17.7%]), and N. meningitidis (n = 766 [21.4%]). Among confirmed bacterial meningitis cases with outcome reported, 11.0% died; case fatality ratio varied by pathogen (S. pneumoniae, 12.2%; H. influenzae, 6.1%; N. meningitidis, 11.0%). Among the 277 children who died with confirmed bacterial meningitis, 189 (68.2%) had confirmed S. pneumoniae. The proportion of pneumococcal cases with pneumococcal conjugate vaccine (PCV) serotypes decreased as the number of countries implementing PCV increased, from 77.8% (n = 273) to 47.5% (n = 248). Of 397 H. influenzae specimens serotyped, 49.1% (n = 195) were type b. Predominant N. meningitidis serogroups varied by region. CONCLUSIONS: This multitier, global surveillance network has supported countries in detecting and serotyping the 3 principal invasive bacterial pathogens that cause pediatric meningitis. Streptococcus pneumoniae was the most common bacterial pathogen detected globally despite the growing number of countries that have nationally introduced PCV. The large proportions of deaths due to S. pneumoniae reflect the high proportion of meningitis cases caused by this pathogen. This global network demonstrated a strong correlation between PCV introduction status and reduction in the proportion of pneumococcal meningitis infections caused by vaccine serotypes. Maintaining case-based, active surveillance with laboratory confirmation for prioritized vaccine-preventable diseases remains a critical component of the global agenda in public health.The World Health Organization (WHO)-coordinated Invasive Bacterial Vaccine-Preventable Disease (IB-VPD) Surveillance Network reported data from 2014 to 2019, contributing to the estimates of the disease burden and serotypes of pediatric meningitis caused by Streptococcus pneumoniae, Haemophilus influenzae and Neisseria meningitidis

Role of age and comorbidities in mortality of patients with infective endocarditis

[Purpose]: The aim of this study was to analyse the characteristics of patients with IE in three groups of age and to assess the ability of age and the Charlson Comorbidity Index (CCI) to predict mortality. [Methods]: Prospective cohort study of all patients with IE included in the GAMES Spanish database between 2008 and 2015.Patients were stratified into three age groups:<65 years,65 to 80 years,and ≥ 80 years.The area under the receiver-operating characteristic (AUROC) curve was calculated to quantify the diagnostic accuracy of the CCI to predict mortality risk. [Results]: A total of 3120 patients with IE (1327 < 65 years;1291 65-80 years;502 ≥ 80 years) were enrolled.Fever and heart failure were the most common presentations of IE, with no differences among age groups.Patients ≥80 years who underwent surgery were significantly lower compared with other age groups (14.3%,65 years; 20.5%,65-79 years; 31.3%,≥80 years). In-hospital mortality was lower in the <65-year group (20.3%,<65 years;30.1%,65-79 years;34.7%,≥80 years;p < 0.001) as well as 1-year mortality (3.2%, <65 years; 5.5%, 65-80 years;7.6%,≥80 years; p = 0.003).Independent predictors of mortality were age ≥ 80 years (hazard ratio [HR]:2.78;95% confidence interval [CI]:2.32–3.34), CCI ≥ 3 (HR:1.62; 95% CI:1.39–1.88),and non-performed surgery (HR:1.64;95% CI:11.16–1.58).When the three age groups were compared,the AUROC curve for CCI was significantly larger for patients aged <65 years(p < 0.001) for both in-hospital and 1-year mortality. [Conclusion]: There were no differences in the clinical presentation of IE between the groups. Age ≥ 80 years, high comorbidity (measured by CCI),and non-performance of surgery were independent predictors of mortality in patients with IE.CCI could help to identify those patients with IE and surgical indication who present a lower risk of in-hospital and 1-year mortality after surgery, especially in the <65-year group