Influenza in Human
Conditions
Keywords
influenza, quadrivalent influenza vaccine, influenza vaccine effectiveness, pregnancy, pregnant women, infants
Brief 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.
Interventions
None listed
Sponsors
Hellenic Pasteur Institute
University of Athens
Study design
Observational model
COHORT
Time perspective
PROSPECTIVE
Eligibility
Sex/Gender
FEMALE
Age
18 Years to 45 Years
Healthy volunteers
Yes
Inclusion criteria
Pregnant women \>18 years old and \<45 years old, cared at Alexandra General Hospital (Athens, Greece) between October 16 and January 27, 2020
Exclusion criteria
* \<18 years old or \>45 years old * not in stable health * already vaccinated against influenza * history of Guillain-Barré syndrome * history of hypersensitivity to influenza vaccines * immunosuppression * history of investigational drug \<30 days * history of immunoglobulins or blood products \<3 months * fever at day of interview (enrollment day)
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| rates of laboratory-confirmed influenza in vaccinated and unvaccinated pregnant women | 2019-2020 influenza season | influenza vaccine effectiveness against laboratory-confirmed influenza in pregnant women |
| rates of laboratory-confirmed influenza in young infants whose mothers were vaccinated and in infants of unvaccinated mothers | 2019-2020 influenza season | influenza vaccine effectiveness against laboratory-corfirmed influenza in young infants |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| rates of acute respiratory infection, influenza-like illness, febrile episode, use of antibiotics, use of antivirals, pneumonia, acute otitis media (for infants only), healthcare seeking and hospitalization in pregnant women and their infants | 2019-2020 influenza season | influenza vaccine effectiveness against the abovementioned secondary outcomes |
Countries
Greece
Outcome results
None listed