Hepatitis-A-vaccine/typhoid-vaccine

ABSTRACTThe geometric mean concentration (GMC) and the proportion maintaining a protective level (150 enzyme-linked immunosorbent assay (ELISA) units [ELU]/ml) 2 years following a single dose of 25 μg of injectable Vi capsular polysaccharide typhoid vaccine was measured against that of the control hepatitis A vaccine in children 2 to 16 years old in cluster randomized trials in Karachi and Kolkata. The GMC for the Vi group (1,428 ELU/ml) was statistically significantly different from the GMC of the control hepatitis A vaccine group (86 ELU/ml) after 6 weeks. A total of 117 children (95.1%) in the Vi group and 9 (7.5%) in the hepatitis A group showed a 4-fold rise in Vi IgG antibody concentrations at 6 weeks (P< 0.01). Protective antibody levels remained significantly different between the two groups at 2 years (38% in the Vi vaccine groups and 6% in the hepatitis A group [P< 0.01]). A very small proportion of younger children (2 to 5 years old) maintained protective Vi IgG antibody levels at 2 years, a result that was not statistically significantly different compared to that for the hepatitis A group (38.1% versus 10.5%). The GMCs of the Vi IgG antibody after 2 years were 133 ELU/ml for children 2 to <5 years old and 349 ELU/ml for children 5 to 16 years old. In conclusion, Vi capsular polysaccharide typhoid vaccine is immunogenic in children in settings of South Asia where typhoid is highly endemic. The antibody levels in children who received this vaccine remained higher than those in children who received the control vaccine but were significantly reduced at 2 years of follow-up.

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Adverse Events Following Immunization With Combined vs Concurrent Monovalent Hepatitis A and Typhoid Vaccines in Children

Journal of the Pediatric Infectious Diseases Society ◽

10.1093/jpids/piaa031 ◽

2020 ◽

Author(s):

Luis Furuya-Kanamori ◽

Paul Dutton ◽

Alan Leeb ◽

Deborah J Mills ◽

Ross Andrews ◽

...

Keyword(s):

Adverse Events ◽

Hepatitis A ◽

Typhoid Vaccine ◽

Off Label ◽

Combined Vaccine ◽

Typhoid Vaccines

Abstract Combined hepatitis A and typhoid vaccine is available in Australia, but licensed for use from age 16 years; however it is used “off-label” in children. The combined vaccine is well tolerated in children aged 2–16 years and the risk of adverse events is similar to those receiving concurrent monovalent vaccines.

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Application of solid-phase immune electron microscopy to study physical and stability characteristics of enterically transmitted non-a, non-b hepatitis virus

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100102481 ◽

1988 ◽

Vol 46 ◽

pp. 80-81

Author(s):

Charles D. Humphrey ◽

E. H. Cook ◽

Karen A. McCaustland ◽

Daniel W. Bradley

Keyword(s):

Electron Microscopy ◽

Hepatitis A ◽

Hepatitis A Virus ◽

Solid Phase ◽

Etiologic Agent ◽

World Health ◽

Health Concern ◽

Morphological Identification ◽

Immune Electron Microscopy

Enterically transmitted non-A, non-B hepatitis (ET-NANBH) is a type of hepatitis which is increasingly becoming a significant world health concern. As with hepatitis A virus (HAV), spread is by the fecal-oral mode of transmission. Until recently, the etiologic agent had not been isolated and identified. We have succeeded in the isolation and preliminary characterization of this virus and demonstrating that this agent can cause hepatic disease and seroconversion in experimental primates. Our characterization of this virus was facilitated by immune (IEM) and solid phase immune electron microscopic (SPIEM) methodologies.Many immune electron microscopy methodologies have been used for morphological identification and characterization of viruses. We have previously reported a highly effective solid phase immune electron microscopy procedure which facilitated identification of hepatitis A virus (HAV) in crude cell culture extracts. More recently we have reported utilization of the method for identification of an etiologic agent responsible for (ET-NANBH).

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Hepatitis A Antigen in Liver, Bile and Stool

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100115328 ◽

1975 ◽

Vol 33 ◽

pp. 340-341

Author(s):

D.R. Jackson ◽

J.H. Hoofnagle ◽

A.N. Schulman ◽

J.L. Dienstag ◽

R.H. Purcell ◽

...

Keyword(s):

Hepatitis A ◽

Liver Enzymes ◽

Hepatitis A Virus ◽

Type A ◽

Initial Study ◽

Virus Like Particle ◽

Elevated Liver Enzymes ◽

Ag Particles ◽

Ag Particle ◽

Human Stool

Using immune electron microscopy Feinstone et. al. demonstrated the presence of a 27 nm virus-like particle in acute-phase stools of patients with viral hepatitis, type A, These hepatitis A antigen (HA Ag) particles were aggregated by convalescent serum from patients with type A hepatitis but not by pre-infection serum. Subsequently Dienstag et. al. and Maynard et. al. produced acute hepatitis in chimpanzees by inoculation with human stool containing HA Ag. During the early acute disease, virus like particles antigenically, morphologically and biophysically identical to the human HA Ag particle were found in chimpanzee stool. Recently Hilleman et. al. have described similar particles in liver and serum of marmosets infected with hepatitis A virus (HAV). We have investigated liver, bile and stool from chimpanzees and marmosets experimentally infected with HAV. In an initial study, a chimpanzee (no.785) inoculated with HA Ag-containing stool developed elevated liver enzymes 21 days after exposure.

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