ABSTRACT
In Argentina, the four strategies of epidemiological surveillance from the National System of Health Surveillance (SNVS) are Diseases of Mandatory Report (C2), Sentinel Units (SU), Laboratory Surveillance (SIVILA) and National Programs (National Plan of Blood, information from blood banks). They collect information about viral hepatitis (VH). The objective of this work was to analyze the information recorded by the SUs of VH for hepatitis B and C in the period between January 1th 2007 and December 31h 2010. In this period, out of the 1,769 cases recorded (entered by 21 of 24 SUs), 806 entries were hepatitis B, 848 hepatitis C and 115 belonged to other definitions. The relative proportions between hepatitis B and hepatitis C were heterogeneous between the SUs. The age distribution was homogeneous, being the predominant group in acute hepatitis B the 25- to 34-year-old group. In hepatitis C, the age distribution was broader. The distribution by sex and risk factors was heterogeneous between the different SUs. In hepatitis C, genotype 1 was the predominant one. In conclusion, the information provided by the SUs contributes as an evidence of the public health problem posed by this pathology in our country.
Subject(s)
Hepatitis B/epidemiology , Hepatitis C/epidemiology , Sentinel Surveillance , Adult , Argentina/epidemiology , Age Distribution , Sex Distribution , Risk Factors , Female , Humans , Male , Disease Notification , Middle AgedABSTRACT
La infección por el virus de hepatitis A (HAV) es endémica en Argentina. El uso de técnicas moleculares permitió extender la detección del RNA del HAV en sueroy heces en pacientes con diferentes presentaciones clínicas. Comparamos la sensibilidad del protocolo de RT-PCR que usamos con cebadores dirigidos a distintas regiones del genoma, resultando la detección de la región VP3 C terminal la más sensible. Se obtuvieron prospectivamente muestras de suero y materia fecal de 20 niños con hepatitis aguda autolimitada por HAV. El RNA del HAV fue detectado en 18/20 niños en muestras basales y en 19/20 sumando una muestra posterior. El RNA del HAV fue detectable en 9/20 acientes hasta 30 días en suero; en materia fecal en 2/20 hasta 60 días y en 1/20 hasta 90 días. La secuencia genómica para la región VP1/2A en 8 muestras demostró que todas pertenecían al subgenotipo IA, aunque eran diferentes entre sí. Solo en 1/11 niños con falla hepatica fulminante fue posible la detección del RNA del HAV utilizando la región VP3 C terminal y el genotipo fue I. La reciente introducción de la vacunación universal en niños de 1 año de edad en Argentina podría disminuir drásticamente la circulación del virus, emergiendo nuevas fuentes de infección y permitiendo la introducción de nuevos genotipos. Las técnicas moleculares aplicadas al estudio de la historia natural de la infección y a la vigilancia epidemiológica contribuyenal control y la toma de decisiones eficientes en políticas de Salud Pública.
Hepatitis A virus (HAV) infection is endemic in Argentina. Molecular tools have allowed HAV RNA detection to be extent to sera and feces from patients with different clinical backgrounds. We compare the sensitivity of the RT-PCR protocol we follow using primers targeting different genomic regions and VP3 C terminal was the most sensitive. Sequential sera and fecal samples were obtained from 20 children with acute self limited Hepatitis A. HAV RNA was detectable in 18/20 children if sera and stool specimens were collected at the onset of symptoms and in 19/20 if a later sample was considered. HAV RNA was detectable in serum from 9/20 patients until day 30 and in feces from 2 patients until day 60 and until day 90 in one. Genomic sequences from VP1/2A region in 8 samples showed they all belong to subgenotype IA although they were different between them. HAV RNA was detectable only in 1/11 sera from children with acute liverfailure when VP3 C terminal fragment was searched and it belonged to genotype I. Universal vaccination in one year old children was recently implemented in Argentinaand it will dramatically enable the decrease of the viral circulation, making new sources of infection emerge and allowing the introduction of new genotypes. The application of molecular tools to the study of the natural history of infection and to the epidemiologicsurveillance may contribute to efficient control and lead to rational decisions in public health policies.
Subject(s)
Humans , Male , Female , Infant , Child, Preschool , Child , Adolescent , Feces/virology , Hepatitis A/diagnosis , Hepatovirus/isolation & purification , Viremia/virology , Virus Shedding , Acute Disease , Hepatitis A/complications , Hepatitis A/virology , Hepatovirus/genetics , Liver Failure, Acute/blood , Liver Failure, Acute/virology , Molecular Sequence Data , Oligonucleotide Probes , Prospective Studies , RNA, Viral/analysis , Reverse Transcriptase Polymerase Chain Reaction , Sensitivity and Specificity , Time FactorsABSTRACT
Las cepas de virus de hepatitis E (HEV) encontradas en casos esporádicos humanos y en cerdos en Argentina corresponden al genotipo 3. Se han descripto variantes de este genotipo asociadas a fallas hepáticas fulminantes (FHF) en adultos de Japón e Inglaterra. En Argentina el 30% de las FHF en adultos y en niños es de etiología desconocida. Para estudiar si el HEV podría ser el agente etiológico asociado a FHF en niños se analizaron el suero y/o la materia fecal de 35 niños (edad media 6 años, 20 mujeres, 15 varones) durante 2003 y 2004. El HEV RNA fue detectado por RT-nested PCR con cebadores dirigidos a las regiones ORF 1 y ORF 2. El HEV RNA pudo detectarse en 3 casos. Dos eran varones de 12 años residentes en la provincia de Buenos Aires y el tercero, una niña de 3 años de la provincia de Corrientes. El análisis de las secuencias muestra que las 3 variantes son distintas, pero pertenecen todas al genotipo 3 y están muy relacionadas a las cepas encontradas previamente en casos esporádicos en humanos y en cerdos de Argentina. Estos datos sugieren una posible relación entre FHF y HEV en niños de Argentina e indican la necesidad de considerar la infección con HEV en el diagnóstico diferencial de las FHF. Se necesitan más estudios que demuestren el verdadero impacto de esta infección y el beneficio potencial de na vacuna para HEV, actualmente en fase III.
Strains of hepatitis E virus (HEV) isolated from Argentinian patients with sporadic hepatitis, as well as from swine from Argentina, belong to genotype 3. HEV genotype 3 variants have been described associated with acute liver failure (ALF) in adults from Japan and the United Kingdom. In Argentina, 30% of ALF in adults and children are of unknown aetiology. To study if HEV could be an aetiological agent associated with ALF in children, serum and/or fecal samples from 35 children (mean age: 6 years, 20 female, 15 male) were analyzed during 2003 and 2004. HEV RNA was detected by RT-nested PCR with primers designed within ORF 1 and ORF 2 regions. HEV RNA could be detected in three cases. Two were 12-year-old boys from Buenos Aires province and the third was a 3- year-old girl from Corrientes province. Sequence analysis indicates that the three isolates are distinct from each other but all belong to genotype 3, exhibiting a close relationship with swine and human strains from sporadic cases of HEV, previously reported in Argentina. This data suggests a potential link between ALF and HEV in children in Argentina and indicates the need for the determination of HEV status in the differential diagnosis in ALF. Further studies would aid in determining the true impact of this infection in Argentina and the potential benefits of a vaccine against HEV, presently in phase III trials.