Investigation of Immune Amnesia Following Measles Infection in Select African Regions
试验速览
- 阶段
- 不适用
- 状态
- 已完成
- 入组人数
- 264
- 试验地点
- 2
- 主要终点
- Change in pre-existing immunity
研究概览
简要总结
The goal of this observational study is to investigate the effects of measles virus (MeV) infection on pre-existing immunity, vaccine response, and susceptibility to subsequent illness in children aged 1-15 either with or without acute MeV infection.
详细描述
This is a prospective, observational, longitudinal study to be conducted in West Africa. Eligible children will be enrolled into 1 of 2 arms: acute MeV infection (cases) or no acute MeV infection (controls) as assessed using upper respiratory specimens and blood samples. Blood samples will be collected at screening/enrollment (Day 0) and follow-up visits on Day 14, Week 13, and Week 52, and tested for humoral and cellular immune responses to endemic pathogens to determine changes in antibody diversity and antibody secreting cells (ASCs). All children in each arm will receive rabies vaccination (standard 3-dose series given as pre-exposure prophylaxis [PrEP]), with the first dose randomized to either Week 8 or Week 47 after enrollment. Biological samples will be collected after vaccination to assess if the immune stimulus (rabies vaccine) response differs: 1) between children with and without MeV infection, and 2) based on the timing of the receipt of the rabies vaccine.
研究设计
- 研究类型
- Observational
- 观察模型
- Cohort
- 时间视角
- Prospective
入排标准
- 年龄范围
- 1 Year 至 15 Years（Child）
- 性别
- All
- 接受健康志愿者
- 是
入选标准
- •Aged 1 to 15 years.
- •Ability of the participant's legal or culturally acceptable representative to provide informed consent.
- •Ability to give assent, as appropriate.
- •Stated willingness of parent/guardian and participant as appropriate, to comply with all study procedures.
- •Willingness to receive rabies vaccine.
- •Meet the criteria for assignment to Group 1 or Group 2, as follows:
- •Group 1, cases (acute MeV infection):
- •Clinical signs and symptoms suggestive of acute MeV infection (Koplik spots or skin rash) AND
- •Laboratory confirmed measles:
- •Upper respiratory specimen (swab) PCR for measles positive, OR
- •Serum IgM for measles positive.
- •Group 2, controls (no acute MeV infection):
- •No clinical signs and symptoms suggestive of acute MeV infection (Koplik spots or skin rash) AND
- •Upper respiratory specimen (swab) PCR negative for MeV AND
- •Serum measles IgM negative AND
- •Serum measles IgG positive and previously vaccinated for measles (2nd dose will be offered if appropriate). If serum measles IgG is negative, participant must be willing to be vaccinated regardless of prior measles vaccine history to meet this criterion.
排除标准
- •HIV infection or any other immunosuppressive condition or medications.
- •Pregnant or lactating.
- •History of prior measles or immunologic evidence of prior measles in the absence of prior measles vaccination.
- •Severe anemia, defined as hemoglobin less than 8 g/dL.
- •Any acute or chronic condition which, in the opinion of the investigator, constitutes a contraindication to participation in this study.
研究组 & 干预措施
Group 1 - Actue MeV Infection
Participants have acute MeV infection.
干预措施: Verorab (Biological)
Group 2 - No Actue MeV Infection
Participants do not have acute MeV infection.
干预措施: Verorab (Biological)
结局指标
主要结局
Change in pre-existing immunity
时间窗: Week 13 after baseline
Mean change in a panel of antibody levels over 13 weeks as measured by multiplex serological methods and targeted ELISAs for confirmation.
Effect of MeV infection on immune response to a controlled immune stimulus (rabies vaccination)
时间窗: 14 days after last PrEP regimen vaccination
Proportion of subjects with rabies virus neutralizing antibodies (RVNA) titer ≥ 0.5 IU/mL as measured by rapid fluorescent focus inhibition test
Effect of MeV infection on immune response to a controlled immune stimulus
时间窗: 5-6 weeks after the first rabies vaccine dose
Proportion of subjects with an RVNA titer ≥ lower limit of quantification
次要结局
- Change in pre-existing immunity(Week 52 after baseline)
- Change in healthcare system encounters(1 year following enrollment)