NCT04723771

Influenza Vaccine Effectiveness of a Quadrivalent Vaccine in Pregnant Women and Young Infants, 2019-2020

Influenza Vaccination Effectiveness of a Quadrivalent Inactivated Vaccine in Pregnant Women and Young Infants (Aged 6 Months and Below) During Influenza Season 2019/2020

• Status: Completed
• Phase: —
• Study type: Observational
• Enrollment: 949 (actual)
• Sponsor: University of Athens · Academic / Other
• Sex: Female
• Age: 18 Years – 45 Years
• Healthy volunteers: Accepted

Summary

Influenza is associated with an increased risk for serious illness, hospitalization and death in pregnant women and young infants. The investigators estimated the effectiveness of a quadrivalent inactivated influenza vaccine (QIV) in pregnant women and their infants in 2019-2020 influenza season. Women were activelly followed during the influenza season on a weekly basis through telephone call in order to collect data about the onset of fever and/or respiratory symptoms by them or their young infants. Polymerase chain reaction testing in pharyngeal samples was offered to pregnant women and infants with influenza-like illness (ILI). A total of 636 pregnant women and 474 infants were studied. A Bayesian beta-binomial model was used.

Detailed description

Study period: Influenza 2019-2020 season The investigators followed actively the pregnant women and their infants in order to collect prospectively data on a weekly basis through phone calls during the entire influenza season. Definitions: * ILI was defined as the sudden onset of symptoms and fever, malaise, myalgia or headache, and cough, sore throat or shortness of breath. * ARI was defined as the presence of at least one respiratory symptom, regardless of fever. * Febrile episode was defined as the presence of fever only. * Fever was defined as a temperature of 38.0 C in at least two measurements within 24h. * The diagnoses of pneumonia and AOM were accepted as reported by the physicians who provided care to the women or their infants. The 2019-2020 QIV Vaxigrip-Tetra was used to vaccinate pregnant women.

Conditions

• Influenza in Human

Timeline

• Start date: 2019-09-01
• Primary completion: 2020-04-30
• Completion: 2020-08-31
• First posted: 2021-01-26
• Last updated: 2021-05-11

Locations

1 site across 1 country: Greece