Study of the Long Term Efficacy of Recombinant Hepatitis B Vaccine in Young Adults 20-22 Years After the Primary Vaccination in Nile Delta of Egypt
试验速览
- 阶段
- 不适用
- 发起方
- 入组人数
- 200
- 试验地点
- 1
- 主要终点
- Number of individuals with protective anti-HBs antibody titers
研究概览
简要总结
More than two billion individuals have serological evidence of hepatitis B virus (HBV) infection worldwide. Of these, 240 million are chronic carriers and approximately 786,000 hepatitis B related deaths occur annually.
Currently available hepatitis B vaccines are extremely safe and have an efficacy of >90 percent against all HBV serotypes and genotypes. Thus, HBV infection can potentially be eradicated through global vaccination. A positive immune response to the vaccine is defined as the development of hepatitis B surface antibody (anti-HBs) at a titer of >10 mIU/mL.
Although anti-HBs titers decrease with time, the duration of protection is long. Protection has been estimated to persist for up to 22 years after the primary vaccination schedule. Protection from clinical disease, despite declining or even undetectable anti-HBs levels, is probably due to the priming of memory cells, which are capable of eliciting an anamnestic response when challenged. This is supported by the rapid increases in anti-HBs titers in previously vaccinated individuals who administered booster injections.
详细描述
A significant proportion of the vaccinated population loses both the protective levels of anti-HBs and an anamnestic response. Recommendations for booster vaccination have been proposed in a European consensus statement. Countries like the Netherlands, Germany, Spain, France and Belgium recommend a booster dose depending on the post-vaccination anti-HBs titer. In the UK, a single booster dose is recommended five years after primary vaccination.
In Egypt, the routine infant immunization for hepatitis B virus started in 1992, and was given at 2nd, 4th and 6th months of age. In the present study the investigators will investigate the long term efficacy of hepatitis B vaccination in young adults 20 to 22 years after the primary vaccination in Nile Delta of Egypt.
研究设计
- 研究类型
- Observational
- 观察模型
- Case Only
- 时间视角
- Cross Sectional
入排标准
- 年龄范围
- 20 Years 至 22 Years（Adult）
- 性别
- All
- 接受健康志愿者
- 是
入选标准
- •Age 20-22 years
- •Administration of HBV vaccine during routine infant immunization (2nd, 4th, 6th months after birth)
排除标准
- •Overt co-morbid condition
- •Treatment with immune-modulatory or immune-suppressive drugs
结局指标
主要结局
Number of individuals with protective anti-HBs antibody titers
时间窗: 1 year
Number of individuals having protective anti-HBs antibody titers
次要结局
未报告次要终点
研究者
Sherief Abd-Elsalam
Consultant liver and GIT diseases- Tanta university hospital
Tanta University