The Effect of Giving BCG Vaccine at Birth to Low Birth-weight Infants on Development of Allergy and Asthma in Childhood - Follow up of a Randomised Trial in Guinea-Bissau
试验速览
- 阶段
- 不适用
- 状态
- 已完成
- 入组人数
- 487
- 试验地点
- 1
- 主要终点
- Skin prick test
研究概览
简要总结
The prevalence of asthma and allergic diseases is increasing worldwide. Infections and vaccinations in childhood may have an impact on the subsequent development of asthma and allergy. In Guinea-Bissau, the investigators previously found that Bacille Calmette-Guérin (BCG) vaccine was associated with reduction in atopy. Since then the investigators have conducted a randomised trial of BCG vaccine given at birth to low birth-weight infants. The present study aims to follow up children enrolled in the BCG randomised trial to assess for asthma and allergy later in childhood. Based on previous observations, the investigators expect children allocated to receive BCG at birth will have a reduction in allergy profile when compared to children who did not receive BCG at birth.
详细描述
Background: Prevalence of asthma and allergy is increasing worldwide, and the cause is unclear. Previous work by the Bandim Health Project and others has identified that infections and routine childhood vaccinations have an impact on the development of atopic sensitisation and allergic symptoms later in life. A number of these studies have found association between BCG vaccination and reduction in atopy and allergy. Only one randomised trial has been conducted of BCG vaccine to protect against allergy with inconclusive results. The present project provides the opportunity to follow-up children born low birth-weight who were randomised to receive BCG vaccine at birth or to receive BCG later in infancy as part of regular care.
Hypothesis:
- Children given BCG vaccine at birth will have reduced prevalence of positive skin-prick test and allergic symptoms when compared with children who did not receive BCG at birth
- Early BCG vaccination will be associated with reduced prevalence of positive skin prick test and allergic symptoms
- Early DTP vaccination will be associated with increased prevalence of positive skin-prick tests and allergic symptoms
Objectives:
- to examine the effects of environmental factors, including BCG, DTP and measles vaccines, on atopy (determined by skin-prick tests) and symptoms of asthma, eczema and food allergy
- to examine the sex-differential effects of vaccination on atopy and allergic symptoms
- to determine the association between faecal microbial diversity, atopy and food allergy
研究设计
- 研究类型
- Observational
- 观察模型
- Cohort
- 时间视角
- Retrospective
入排标准
- 年龄范围
- 3 Years 至 9 Years（Child）
- 性别
- All
- 接受健康志愿者
- 否
入选标准
- •Previous enrolment in NCT00146302
- •Living within Bandim Health Project study area
排除标准
- •Children with known history of anaphylaxis
- •Children with skin infections or severe skin conditions for who SPT could not be reliably performed
- •Children currently taking anti-histamine medication
结局指标
主要结局
Skin prick test
时间窗: Single observation at time of consent - DAY 1
Skin prick tests to common aero and food allergen
次要结局
- Symptoms of asthma(Single observation at time of consent - DAY 1)
- Symptoms of eczema(Single observation at time of consent - DAY 1)
- Symptoms of food allergy(Single observation at time of consent - DAY 1)