Direct and Indirect Protection by Influenza Vaccine Given to Children in India

描述(由调查员提供)：急性呼吸道感染每年导致约190万儿童死亡，其中20%在印度。印度儿童中流感的疾病负担不明确，但很可能是巨大的。流感疫苗在美国儿童中是常规使用的，尽管在印度获得了许可，但很少有人接种。事实上，目前尚不清楚一个热带发展中国家的流感疫苗效力是否会与发达国家相同。具体目标1.描述流感疫苗的直接效力和间接效力。这一目标将通过以下方式实现：确定在六个月大的儿童中接种流感疫苗对降低儿童中经实验室确认的流感发病率的有效性；以及使用前瞻性、分组随机、对照、观察者盲法研究，确定流感疫苗接种对居住在印度农村同一社区的未接种疫苗的个人的间接影响。两个社区的所有参与研究的个人(儿童和成人)将通过每周的访问积极监测发热性急性呼吸道疾病(发烧、报告的发烧和任何呼吸道症状)的发生。将根据临床体征和症状，包括脉搏血氧饱和度测定，进一步确定每个FARI的特征，并收集呼吸道样本。FARIS的一个主要亚型将接受流感的实时逆转录聚合酶链式反应检测，阳性样本将接受培养以进行病毒分离。将监测和报告与疫苗相关的不良事件。明确目标2.明确流感临床疾病和结局。这一目标将通过确定居住在研究社区的所有年龄段的人的流感疾病结局的比率和流行病学特征来实现，包括严重疾病的发病率。将确定流感疾病的临床表现，包括共病情况、与流感相关的并发症以及与流感引起的更严重疾病相关的风险因素。除了确定流感疫苗的直接和间接保护作用外，这些研究还将在世界第二大国家发展流感病毒研究和管理的能力。

DESCRIPTION (provided by investigator): Acute respiratory infections result in ~ 1.9 million childhood deaths per year, 20% of the deaths are in India. The disease burden of influenza among children in India is ill defined but is likely substantial. Influenza vaccines are in routine use in children in the US, although licensed in India, they are seldom given. Indeed, it is not known whether influenza vaccine efficacy in a tropical developing country will be the same as in developed countries. Specific Aim 1. Describe influenza vaccine direct and indirect efficacy. This aim will be accomplished by determining the efficacy of influenza vaccination in children six months of age through primary school on decreasing the incidence of laboratory-confirmed influenza in the children; and determining the indirect effects of influenza vaccination on laboratory-confirmed influenza among unvaccinated individuals who are living in the same communities in rural India using a prospective, group randomized, controlled, observer-blinded study. All individuals (children and adults) in both communities who participate in the study will be actively monitored by weekly visits for the occurrence of febrile acute respiratory illness (FARI, reported fever and any respiratory complaint). Each FARI will be further characterized on the basis of clinical signs and symptoms, including pulse oximetry, and a respiratory specimen will be collected. A major subset of FARIs will undergo realtime reverse transcriptase polymerase chain reaction testing for influenza, positive samples will be subjected to culture for virus isolation. Vaccine related adverse events will be monitored and reported. Specific Aim 2. Define influenza clinical disease and outcomes. This aim will be accomplished by defining the rates and epidemiological characteristics of influenza disease outcomes in persons of all ages who are living in the study communities, including the incidence of severe disease. The clinical presentations of influenza disease, including co-morbid conditions, influenza-related complications, and risk factors associated with more severe illness due to influenza will be identified. In addition to defining the direct and indirect protective effect of influenza vaccine, these studies will develop capacity for influenza virus study and management in second largest country in the world.