Outcomes of Pandemic Influenza in Pregnancy: an Observational Cohort Study
试验速览
- 阶段
- 不适用
- 入组人数
- 200
- 试验地点
- 8
- 主要终点
- Influenza A(H1N1)v infection: will be as diagnosed by polymerase chain reaction(PCR) from nasal or nasopharyngeal (NP) swabs, and/or seroconversion to influenza A(H1H1)v.
研究概览
简要总结
We propose to follow a cohort of pregnant and post-partum Canadian women through the fall and winter of 2009/2010 and the anticipated second and third waves of the current pandemic in order to better understand the incidence, complications and risk factors for severe disease due to H1N1 influenza in pregnant women, and to contribute data on the safety and effectiveness of antivirals and vaccines in this population.
The primary hypotheses to be tested are:
(i) pandemic influenza infection in the second and third trimester of pregnancy is associated with an increase in adverse fetal outcomes (fetal loss, stillbirth, neonatal mortality, significant neonatal morbidity, prematurity) (ii) close contact with young children (<2 yrs) at home or work is the most important risk factor for influenza in pregnant women (iii) higher scores on a scale of community infection prevention (a combination of self-reported hand hygiene adherence, avoidance of ill persons and avoidance of crowds) are protective against influenza (iv) receipt of seasonal influenza vaccine from 2007 to 2009 will increase the risk of illness due to influenza A(H1N1)v in the second and third waves of the pandemic.
(v) pandemic influenza vaccine is effective in preventing symptomatic influenza in pregnant women.
(vi) vaccination of pregnant women against a particular strain of influenza protects their infants against influenza infection in the first six months of life.
详细描述
Subjects will be consented to participate in the study. They will complete a web-based baseline questionnaire. Participants will be given a nasal swab kit with instructions for obtaining swabs. Baseline blood (10mls) will be drawn for influenza serology and for measurement of total IgG and IgG subtypes. An email will be sent to each participant within 24 hours of their enrolment to welcome them to the study.
Participants will be asked to complete a weekly diary using web-based data entry. An email will be sent to each participant every Monday during the study reminding the participant to complete their weekly diary and to report and submit a nasal swab if they have any symptoms of an acute respiratory illness. Reminder emails will be sent 48 hours later if the weekly form remains incomplete. Participants will be telephoned if forms remain incomplete for three weeks. Weekly emails will also be used to update participants about vaccine availability, current vaccine recommendations, and any changes in expert recommendations for pregnant women.
Once every four weeks additional questions will be asked on the weekly survey. If any participant develops symptoms compatible with an acute viral respiratory illness they will be asked to collect and submit a nasal swab as soon as possible after the onset of symptoms and to complete an illness starting the day of symptom onset and ending when all symptoms are either absent or mild, or for 3 days, whichever is longer. Subjects will be notified if results are positive for influenza along with the local Medical Officer of Health. Treatment for influenza will be discussed with each infected participant by a physician investigator.
Repeat serology and blood for total IgG and IgG subtype will be drawn at the time of delivery to the six week post partum. Women will notify the study when they are admitted for delivery or termination of pregnancy and will be interviewed either in person at the hospital, or over the telephone within 3 weeks of delivery. A chart review will be performed to identify any complications at delivery or termination, and to record neonatal outcomes. Post-partum, mothers will continue their own weekly and illness diaries and weekly diaries for their infants will be added.
Pregnant women requiring hospital admission for influenza in hospitals participating in surveillance for the Toronto Invasive Bacterial Diseases Network (TIBDN) and Serious Outcomes Surveillance (SOS) for the PHAC/CIHR Influenza Research Network (PCIRN), as well as pregnant women with influenza admitted to intensive care units as part of the Canadian Critical Care Clinical Trials Group Influenza Surveillance System (ICU-Flu) will be approached. Risk factor data from the baseline and weekly questionnaires will be collected retrospectively from these women. With consent, women will be followed to delivery/termination, and the same information collected regarding neonatal outcomes as was collected for other women in the cohort.
研究设计
- 研究类型
- Observational
- 观察模型
- Cohort
- 时间视角
- Prospective
入排标准
- 性别
- Female
- 接受健康志愿者
- 是
入选标准
- •Participants must:
- •be and pregnant, and, at the time of enrolment, not more than 30 weeks gestation.
- •be greater than or equal to 16 years of age
- •give written informed consent prior to entry
- •be available for follow-up during the study period
- •have convenient access to a computer with internet access
- •know basic skills for use of the internet
- •have the ability to complete questionnaires in either English or French
排除标准
- 未提供
结局指标
主要结局
Influenza A(H1N1)v infection: will be as diagnosed by polymerase chain reaction(PCR) from nasal or nasopharyngeal (NP) swabs, and/or seroconversion to influenza A(H1H1)v.
时间窗: October 2009 to June 2010
Primary analysis for risk factors for infection will consider only symptomatic infection, defined as acute respiratory illness/ influenza like illness (fever (at least one measured T\>=38°C) and cough and one other local or systemic symptom compatible with influenza) during the pregnancy with seroconversion to A(H1N1)v not explained by vaccination. Seroconversion defined as a 4 fold increase in hemagglutination inhibition titer from 1st to 2nd serum sample. Symptoms compatible with influenza defined as fever, cough, coryza, generalized myalgias, sore throat, headache, severe fatigue.
次要结局
- Adverse fetal/neonatal outcome.(October 2009-June 2010)