Initial evaluation of universal immunization with a single dose against hepatitis A virus in Central Brazil

ABSTRACT Vaccination against the hepatitis A virus (HAV) administered in two doses has been used effectively in universal child immunization programs in several countries. A single-dose vaccination was adopted in some low-income countries in an attempt to reduce costs without losing effectiveness. In 2014, single-dose universal vaccination was introduced in Brazil for children aged two years. Since such strategy is still not universally accepted, its efficacy should be compared to the two-dose strategy. To assess the humoral response after the single-dose HAV vaccination schedule, a cross-sectional study was conducted in Primavera do Leste, in Mato Grosso state, Central Brazil, including 265 children vaccinated through the National Immunization Program. Blood was collected by using a digital puncture and further applied to filter paper cards. Anti-HAV was detected in 218 out of 265 dried blood spots (DBS). Blood venous samples were collected from 34 out of 47 children who were not anti-HAV positive in DBS samples. Eighteen of them tested positive for anti-HAV, giving a final score of 93.6% (236/252) of seropositivity. In conclusion, this study demonstrated a high rate of anti-HAV positivity in the short term after single-dose hepatitis A vaccination in the population investigated. Moreover, the DBS was shown to be a reliable tool for detecting anti-HAV antibodies.

Vaccination Policy in Korean Armed Forces: Current Status and Future Challenge

Infectious diseases have historically resulted in suspended or cancelled military operations. Vaccination for disease prevention is a critical component of the military's force readiness doctrine. Until recently, Korea had not recognized the importance of vaccinating military personnel. However, a 2011 meningococcal disease outbreak at an army recruit training center led to dramatic changes in the paradigm of traditional medical practice in the Korean armed forces. A new vaccination policy was formed by a 2012 Military Healthcare Service Act. Since then, Neisseria meningitidis, hepatitis A, and measles-mumps-rubella vaccines have been routinely administered to all new recruits early in basic training to ensure protection against these diseases. All active-duty soldiers also receive seasonal influenza vaccination annually. Despite quantitative improvements in vaccination policies, several instances of major infectious diseases and adverse vaccine reactions have threatened soldier health. In the future, vaccination policies in the Korean armed forces should be based on epidemiologic data and military medical research for vaccine use and safety management.

Seroprevalence of hepatitis A immunity among brazilian adult patients with liver cirrhosis: is HAV vaccination necessary?

BACKGROUND: Patients with chronic liver disease have a higher risk of fulminant hepatitis when infected with hepatitis A virus, and vaccination of these patients against such infection is recommended. In Brazil, mainly in the South and Southeast regions, the epidemiology of hepatitis A (HA) has shifted from high to intermediate endemicity, which would have implication on policy of HA vaccination for these populations. OBJECTIVE: To verify the prevalence of HA immunity in adult patients with liver cirrhosis (LC), in Uberlândia MG, a city of Southeastern Brazil. METHODS: Between December 2005 and December 2006, 106 patients with LC were consecutively evaluated. In addition, 75 individuals without LC or alcoholism were evaluated (control group - CG). RESULTS: Total anti-HAV (ELISA methods) was positive in 104 (98.1 percent) patients with LC (82 men, 24 women; mean age, 53.3 ± 11.9 years) and in 74 (98.7 percent) individuals of the CG (55 men, 20 women; mean age, 47 ± 11.6 years), p > 0.05. CONCLUSIONS: For patients with chronic liver disease, in the geographic regions and age groups evaluated, routine vaccination against hepatitis A is not recommended. Moreover, the serum determination of total anti-HAV, used to assess immunity, is five times cheaper than vaccination against hepatitis A and, for this reason, should precede vaccination.

Epidemiological transition of hepatitis A in India: issues for vaccination in developing countries.

With improvement in economic and living conditions of the communities, the age of acquiring hepatitis A virus (HAV) infection is shifting from early childhood to adolescence and young adulthood. Such epidemiological shift leads to an increased incidence of symptomatic HAV infection, including heightened risk of liver failure. Data from India indicate that the population is no longer homogeneous for its HAV exposure profile. Occasional outbreaks of HAV and higher proportions of symptomatic cases are reported amongst older children and adults from different regions of the country. However, the heterogeneous exposure to HAV defies widespread use of the vaccine. The challenge is to recognize the susceptible pockets and take pre-emptive steps. In regions with rapid improvement in living standards and environmental hygiene, there is a need for regular surveillance through structured protocols that are able to identify early signs of epidemiological shift. This review discusses relevant issues and concerns to influence decision making for HAV vaccination in such transition societies.

Vacuna anti hepatitis A / Hepatitis A vaccine

La vacuna anti hepatitis A inactivada es una valiosa herramienta preventiva por su alta inmunogenicidad, inducción de memoria, eficacia y perfil de seguridad. Puede ser utilizada a partir de los 12 meses de vida con excelente seroconversión. Las diferentes vacunas son intercambiables entre sí facilitando su uso en salud pública. La mayor utilidad en países con endemia mediana como Chile está en su uso programático en cohortes y en el control de brotes epidémicos circunscritos. Además representa una estrategia alternativa a la inmunoglobulina normal en el manejo de contactos estrechos en el hogar y en instituciones cerradas. En este artículo se revisan in extenso las experiencias publicadas que fundamentan estas aseveraciones.