Household Transmission of Zoonotic Influenza Viruses in a Cohort of Egyptian Poultry Growers
试验速览
- 阶段
- 不适用
- 状态
- 已完成
- 入组人数
- 2,400
- 试验地点
- 1
- 主要终点
- Incidence of avian influenza (AI) in poultry-exposed populations
研究概览
简要总结
This study seeks to determine the incidence and transmission of avian influenza viruses in humans exposed to poultry. Enrolled subjects will be selected from five different rural areas (villages) in the Nile delta region in Egypt where poultry are commonly raised. From those study sites, 2400 healthy subjects will be monitored for 6 years with annual follow up visits to measure sero-prevalence and exposure variables, and more importantly, biweekly or weekly visits to measure incidence of infection, measure secondary transmission rates, monitor symptoms, and assess immunological response.
Primary Objectives:
- To estimate the incidence of avian influenza (AI) in poultry-exposed human populations.
- To estimate sero-prevalent of AI in poultry-exposed human populations.
- To investigate potential risk factors associated with AI human infections in poultry-exposed individuals.
- To investigate secondary infection risk for household contacts.
Secondary Objectives:
- To characterize the antigenic and genetic makeup of AI viruses infecting humans.
- To monitor the pathogenicity and disease severity of AI viruses causing human infections and the associated immune response.
- To investigate the serologic response following confirmed influenza virus infection.
详细描述
All residents of a household will be invited to participate. After study enrollment, participants will complete a questionnaire to collect data on the demographics and health status of the subjects and the poultry kept at the household. A 3-ml blood sample will be obtained from each subject for serological testing.
Field nurses or physicians will visit each household biweekly (October through March) or weekly (April through September) to determine if any subject has influenza-like illness (ILI), defined according to Centers for Disease Control (CDC) criteria as having measured fever of ≥38ºC. and cough and/or sore throat. Subjects with confirmed ILI (index case) will provide two nasal swabs for a point-of-care rapid influenza A test and PCR. For those who test positive for influenza A by rapid test or PCR on nasal swab (day 1), two 3-ml blood samples will be obtained. In addition, nasal washes, throat swabs, and blood samples will be obtained from all household contacts.
Cloacal swabs will also be collected from the poultry in the household on day 1.
The index case and household contacts will be re-sampled by nasal wash and throat swab on days 3, 6, 9 and 14 post initial diagnosis data, and an additional 3-ml blood sample will be obtained on day 14 for serological testing.
Household contacts who report ILI symptoms during follow-up visits to the index case will then be followed with the same follow-up regimen as the original index case.
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
- 2 Years 至 —(Child, Adult, Older Adult)
- 性别
- All
- 接受健康志愿者
- 是
入选标准
- •Poultry-exposed individuals with poultry in the household willing to participate by signing a consent or assent form as appropriate for age, completing the study questionnaire, and permitting the withdrawal of blood, nasal washes, nasal swabs, and throat swabs.
排除标准
- •Any known immunosuppressive condition or immune deficiency disease (including HIV infection), or ongoing receipt of any immunosuppressive therapy. (Note that we have chosen to exclude such populations because of their increased risk of acquiring infections, they are relatively few, and are not representative of a national sample.)
- •Terminally ill individuals.
- •Children who are less than 2 years old when baseline enrollment is performed.
结局指标
主要结局
Incidence of avian influenza (AI) in poultry-exposed populations
时间窗: Up to 6 years
New cases of avian influenza (AI) in poultry-exposed human populations will be detected using throat and nasal swabs and nasal washes obtained from subjects using rapid tests and molecular techniques.
Sero-prevalence rates of infection with AI viruses
时间窗: Up to 6 years
Prevalence rates will be measured by the presence of antibodies against AI viruses subtypes using a micro-neutralization assay. Incidence rates will be assessed based on molecular detection of AI infection annually with 95% confidence intervals. Risk or protective factors correlated with infection will be measured using the baseline enrollment questionnaire.
Secondary infection risk for household contacts
时间窗: Up to 6 years
Throat and nasal swabs, blood, and nasal washes will be obtained from household contacts of poultry-exposed individuals with a confirmed influenza A infection. These will be tested for the presence of influenza A viruses or antibodies against influenza A viruses.
Risk factors associated with AI human infections in poultry-exposed individuals
时间窗: Up to 6 years
A questionnaire will be used to collect specific occupational, environmental, and behavioral risk factors. These will be correlated to sero-prevalence and incidence of AI infections.
次要结局
- Serologic response following confirmed influenza virus infection(Up to 6 years)
- Pathogenicity and disease severity of AI viruses causing human infections and the associated immune response(Up to 6 years)
- Antigenic and genetic makeup of AI viruses infecting humans(Up to 6 years)
