Hepatitis E virus infection in Latin America: a review.

Data reported during recent years reveal the complex picture of the epidemiology of hepatitis E virus (HEV) infection in Latin America. Whereas in countries like Argentina and Brazil is almost identical to the characteristic of most countries from North America and Europe, HEV in the Caribbean and Mexico involves the water-borne, non-zoonotic viral genotypes responsible for epidemics in Asia and Africa. Nevertheless, Latin America has been considered a highly endemic region for hepatitis E in the scientific literature, a generalization that ignores the above complexity. In addition, reports from isolated Amerindian communities, which display well known, important and very specific epidemiological features for hepatitis B and D virus infections are neither taken into account when considering the epidemiology of hepatitis E in the region. This review updates compilation of the available information for the HEV infection, both among humans and other mammals, in Latin America, discusses the strengths and the weaknesses of our current knowledge, and identifies future areas of research.

Seroprevalencia de marcadores de hepatitis B y factores de riesgo asociados en pacientes de hemodiálisis de Ciudad de La Habana; 2002-2003 / Prevalence of hepatitis B virus markers and risk factors associated in haemodialysis patients from Havana city; 2002-2003

No disponible

No disponible

Persistencia de anti-HBs en ancianos inmunizados con una vacuna ADN recombinante anti-hepatitis B: dos años de seguimiento / Anti-HBs persistent to immune aged with a DNA recombinant anti-hepatitis B vaccine: two years of follow

Se aplicó la vacuna recombinante cubana contra el virus de la hepatitis B Herberbiovac HB a un grupo de individuos mayores de 65 años, pertenecientes a un hogar de ancianos de Ciudad de la Habana, a la dosis de 20 ug, con el esquema 0,1 y 6 meses para estudiar su inmunogenicidad, la cual fue evaluada a los 2, 7, 12 meses y 2 años después de aplicada la primera dosis. A los 60 días se obtuvo un 47,1 por ciento de títulos protectores (>10 UI/L) y media geométrica (TMG) de 6,04 UI/L. Cuando se evaluó la respuesta inmune a los 7 meses se logró un 100,0 por ciento de seroprotección (>10 UI/L); 78,6 por ciento de buenos respondedores (títulos antiHBs >100 UI/L) y media geométrica de 136,93 UI/L. Al año, la seroprotección también fue del 100 por ciento, y se logró 61,5 por ciento de títulos >100 UI/L y la media geométrica de 204,61 UI/L. La persistencia de niveles de anticuerpos protectores y TMG 2 años después de aplicada la primera dosis de la vacuna fue de 71,4 por ciento y 24,73 UI/L, respectivamente. Estos resultados evidencian el alto poder inmunogénico de esta vacuna, lo que la hace recomendable para la protección de este grupo de edad contra el virus de la hepatitis B

[Immunogenicity of the Heberbiovac-HB vaccine in doses of 10.5 and 2.5 micrograms in 6-9-year-old students]. / Inmunogenicidad de la vacuna Heberbiovac-HB a las dosis de 10,5 y 2,5 micrograms en niños escolares de 6 a 9 años de edad.

The Heberbiovac-HB recombinant hepatitis B vaccine was administered at dosages of 10.5 and 2.5 micrograms in 3 groups of children aged 6-9 with a vaccination schedule at 0, 1 and 6 months of age. The immunogenecity attained between dosages was compared. The seroconversion with protective titres obtained at 2 months varied from 88.9% with 10 micrograms to 79.4% with 2.5 micrograms, whereas at 7 months it was higher than 98% in the 3 groups. The geometrical mean with 10 mg was 136.63 and 2,356.8 UI/L-1; with 5 micrograms, 77.62 and 1,958.9 UI/L-1; and with 2.5 micrograms, 32.15 and 376.3 UI/UL-1, at 2 and 7 months, respectively. A high immunogenic power of the vaccine is observed at dosages of 10 and 5 micrograms with similar results. In spite of the fact that the dosage of 2.5 micrograms is immunogenic, the response is not desirable. These results state the possibility of using a lower dosage (5 micrograms) for a low risk infantile population, which favors the cost-benefit.

[Infection/immunity by hepatitis B virus in an adult population of Havana City. Cuba 1995]. / Infección/inmunidad por el virus de la hepatitis B en una población adulta de Ciudad de La Habana. Cuba 1995.

The results of a study of markers of infection/immunity by hepatitis B virus in a community of the health area in "Cristobal Labra" polyclinics, City of Habana in 1995. The studied healthy adult population was not included in any vaccination strategy with hepatitis B vaccine. Two markers were studied: Hepatitis B surface antigen and its corresponding antibody (anti-HBs). HBsAg-positivity was 1.05% and anti-HBs positivity was 13.39%. Of anti-HBs-positive cases, 13.39% had titers from 10-50 UI/L and the rest (43.68%) had titers over 50 UI/L.

[Filter paper sampling for the detection of anti-hepatitis A IgM antibodies]. / Toma de muestra en papel de filtro para la detección de anticuerpos IgM antivirus de la hepatitis A.

The usefulness of the whole sample taking in filter paper for the detection of anti-HAV IgM is described. 168 serum and filter paper samples were simultaneously compared. No alterations were observed in the specificity of the enzyme-linked immunosorbent assay for the catchment of IgM in the 52 samples of the control group or in the other 116 from patients with clinical suspicion of acute viral hepatitis. A sensitivity, specificity and coincidence of 100% was obtained on comparing the filter paper with the dilution 1:500 with the serum. The correlation established between the values of optical density of the positive results to anti-HAV IgM, the filter paper at dilution 1:500 and the serum was of 0.895. On applying this type of sample taking in a group of hospitalized patients, 100% of coindicence with clinical suspicion was attained. Besides, it was proved its usefulness for the diagnosis of a viral hepatitis outbreak. According to our results, it is recommended the introduction of this type of sample taking in the diagnosis of hepatitis A.

[Immunogenicity of the Heberbiovac-HB vaccine in the physically and mentally handicapped]. / Inmunogenicidad de la vacuna Heberbiovac-HB en impedidos físicos y mentales.

The recombinant DNA Heberbiovac-HB vaccine against hepatitis B was applied to 2 groups of children at 2 homes for the physically and mental disabled at doses of 10 and 5 micrograms with the scheme 0, 1 and 6 months to study its immunogenicity, which was evaluated at 2, 7 and 12 months after the first dose was administered. On the 60th day it was obtained 80.9% of seroprotection in children who received 10 micrograms, whereas in the group that was vaccinated with 5 micrograms 65.0% of seroprotection was attained and there were no significant differences between the groups. 100% of seroprotection (> or = 10 UI/L) was obtained in the 2 vaccinated groups when the immune response was measured 1 month after the third dose was applied. A year later, seroprotection was 100% for the 2 groups of children. The geometrical mean of the antibody titres (TMG) reached levels above 10 UI/L, which is the minimum protector, in the 2 study groups 30 days after the second dose. A month after the third dose, the TMG attained values of 527.7 UI/L in the group of 10 micrograms and of 324.7 UI/L in that of 5 micrograms. No remarkable differences were found between the groups (p < 0.05). Finally, 365 days later, the TMG descended to 139.7 UI/L and 57.3 UI/L in the same groups, respectively. It was demonstrated the high immunogenic power of this vaccine, which makes it recommendable for protecting the physical and mentally disabled children from hepatitis B virus.

[Adverse reactions and immune response to Heberbiovac-HB vaccine administered to infants simultaneously with DPT and VA-MENGOC-BC]. / Reacciones adversas y respuesta inmune de la vacuna Heberbiovac-HB aplicada a lactantes, simultáneamente con la DPT y la VA-MENGOC-BC.

The Cuban recombinant yeast-derived hepatitis B vaccine (Heberbiovac-HB) was administered to 2 groups of infants aged 3 months. A dosage of 10 micrograms was used through a scheme of 0, 1 and 6 and 0, 1, 2 and 12, coinciding with the DPT and anti-meningococcal vaccines, according to the immunization schedule. Reactogenicity and immunogenicity were studied in both groups. The reactions observed were mild and similar to other studies, where fever , erythema and induration were the most common signs. These 2 groups had high percentages of children with titres of antibodies anti HBs above 100 UI/L-1. It is demonstrated the acceptable reactogenicity of the vaccine and the non-immunological interference of other vaccines.

[Infection by hepatitis B and C viruses in high-performance athletes]. / Infección por los virus de la hepatitis B y C en deportistas de alto rendimiento.

It is reported the possible relationship between the infection caused by viral agents of predominantly parenteral transmission, such as the hepatitis B virus (HBV), the hepatitis C virus (HCV), and the human immunodeficiency virus (HIV) and the sports practice. It was conducted a study of seroprevalence of the infection by HBV and HCV in Cuban high performance athletes. Only 1.3% of positivity to the HBV infection was found. This positivity is related to the sports discipline they practice and some considerations are made on this regard.

[Purification and proteic characterization of a Cuban strain of the hepatitis A virus]. / Purificación y caracterización proteica de una cepa cubana del virus de la hepatitis A.

The purification and protein characterization of one of the Cuban isolated strains of hepatitis A virus was carried out. For this, it was necessary to separate the virus from the infected cell by extraction steps with detergents, concentration by ultrafiltration and finally, ultracentrifugation in saccharosoglycerol discontinuous gradient. Protein concentration, as well as the antigenic activity in the different fractions of the gradient were determined. For the protein characterization of the microorganism, those fractions with the greatest specific activity were analyzed by polyacrylamide gel electrophoresis and by Western blotting. It was shown that the viral material was purified and concentrated in the last fractions of the gradient. Bands corresponding to the structural proteins of hepatitis A were observed through electrophoresis and Western blotting.

[The immunogenicity of the Heberbiovac-HB vaccine in the elderly]. / Inmunogenicidad de la vacuna Heberbiovac-HB en ancianos.

The Cuban recombinant vaccine against the hepatitis B virus was applied to a group of individuals over 65 from a geriatric home in Havana City. Dose of 20 ìg were administered within a scheme from 0.1 to 6 months in order to study its immunogenicity, which was evaluated at 2, 7, and 12 months after the first dose. 47.1% of protective titres and geometrical mean of 6.04 UI/L were obtained after 60 days. 100% of seroconversion (UI/L) and seroprotection (10 UI/L) and geometric mean of 136.93 UI/L were obtained when the immune response was evaluated on the 7th month. Finally, after a year, seroconversion and seroprotection were also of 100%, and the geometric mean was of 204.61 UI/L. It was proved the high immunogenic power of this vaccine, which makes it recommendable to protect this age group from the hepatitis B virus.

[The immunogenicity of the Heberbiovac-HB vaccine in children]. / Inmunogenicidad de la vacuna Heberbiovac-HB en niños.

The Cuban recombinant vaccine against hepatitis B virus was applied with doses of 10 ìg to children under 15 in a scheme from 0, 1 to 6 months. The immunogenicity was evaluated at 2, 7, and 12 months and showed 100% of seroconversion with protective titres. 65.9, 100, and 83.5% of the vaccinated attained titres higher that 100 UI/L at 60, 210, and 360 days. The geometrical mean was of 213.6, 8208.2, and 568.0 UI/L, respectively. All the groups obtained 100% of seroconversion; however, there were significant differences (p < 0.05) in favor of the preschool and school children compared with those over 10 as regards the response level (titres higher than 100 UI/L) and the geometrical mean of antibody titres in the 3 samples. It was demonstrated the high immunogenic power of the vaccine at these ages, which makes it recommendable for their protection against the hepatitis B virus (HBV).

[Outbreaks of hepatitis A in the City of Havana in the year 1991]. / Estudio de brotes de hepatitis A ocurridos en Ciudad de La Habana en el año 1991.

Fifty-six outbreaks of hepatitis A infection were studied in City of Havana between January and September, 1991. In 34 of these, the presence of the hepatitis A virus (HAV) was confirmed, either by the detection of specific serum IGM antibodies to the HAV or by the detection of the antigen in the feces of the subjects under study. Diagnosis was not made in some of the outbreaks due to the insufficient number of samples sent to the laboratory. Of the 453 blood serum samples under study, 126 were positive for IGM antibodies to HAV (27.8%): a there was a good correlation between the presence of this immunoglobulin and the levels attained by the alanyl aminotransferase enzyme (ALT). Only in 19 feces samples, of the 263 under study, was the HAV antigen detected, which accounted to 7.2%; it was demonstrated that this marker is not useful for the diagnosis of an outbreak of hepatitis A infection.

[Development and evaluation of an ELISA for the detection of IgM antibodies against the hepatitis A virus]. / Desarrollo y evaluación de un ELISA para la detección de anticuerpos IgM contra el virus de la hepatitis A.

We present the results of the normalization of an IgM capture ELISA method for the diagnosis of type A viral hepatitis with reagents produced in the laboratory and its comparison with the "Diag-A-Hep" commercial ELISA. The results attained were: sensibility by 91%; specificity by 100%; and coincidence of the two systems by 97%. Results are discussed and their relationship with clinical symptoms and epidemiological characteristics is established. The results attained in 13 serum samples taken from patients seen during 2 acute viral hepatitis outbreaks agreed with clinical findings.

[Virologic diagnosis of an outbreak of epidemic hemorrhagic conjunctivitis by an indirect immunofluorescence technique. Cuba.1989]. / Diagnóstico virológico de un brote de conjuntivitis hemorrágica epidémica mediante la técnica de inmunofluorescencia indirecta. Cuba, 1989.

The causative agent of an hemorrhagic conjunctivitis outbreak was assessed through the study of 18 conjunctival exudates using the indirect immunofluorescence technique and isolation in cell culture of human embryo fibroblasts. In addition, 395 paired serum samples were studied and Enterovirus 70 was found to be responsible for the outbreak.