Evaluating the effectiveness of the influenza vaccine during respiratory outbreaks in Singapore's long term care facilities, 2017.
Vaccine
; 37(29): 3925-3931, 2019 06 27.
Article
em En
| MEDLINE
| ID: mdl-31160102
ABSTRACT
Influenza outbreaks occur periodically in Long Term Care Facilities (LTCFs) and vaccination is critical in preventing influenza infections. We evaluated the influenza vaccine effectiveness (VE) during respiratory outbreaks in LTCFs reported to the Ministry of Health, Singapore in 2017. A test-negative design was used to estimate the ratio of the odds of testing positive for influenza among vaccinated individuals to the odds among unvaccinated individuals. The VE was calculated as (1-odds ratio)â¯×â¯100%. For adjusted VE, the estimates were derived using logistic regression adjusted for age group, gender, month of illness, and number of days from date of illness onset till to swab collection date. Estimates by influenza subtypes and post-vaccination time periods (15-180â¯days & 181-365â¯days) were also calculated using stratified data. 264 individuals, with 118 laboratory-confirmed influenza cases [32 A(H1N1)pdm09, 75 A(H3N2), 11 A(untypable)], were included in the analysis. No one was identified to be infected with influenza B. The overall adjusted VE estimate was 40.5% (95% CI -12.2-68.5%), while the subtype-specific adjusted VE estimates were -43.4% (95% CI -312.4-50.2%) against A(H1N1)pdm09 and 57.1% (95% CI 5.7-80.5%) against A(H3N2). At 15-180â¯days post-vaccination period, the adjusted VEs were 59.3% (95% CI 18.0-79.8%) against all influenza, 35.4% (95% CI -123.5-81.3%) against A(H1N1)pdm09 and 67.9% (95% CI 22.5-86.7%) against A(H3N2). Estimates were not significant at 181-365â¯days post-vaccination. The influenza vaccine showed varying effectiveness among individuals in Singapore's LTCFs in 2017, with a higher effectiveness among those who were more recently vaccinated. It remains an important tool in preventing influenza infections, especially for those who are at high risk of influenza-related complications.
Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Vacinas contra Influenza
/
Surtos de Doenças
/
Vacinação
/
Assistência de Longa Duração
/
Influenza Humana
/
Potência de Vacina
Tipo de estudo:
Etiology_studies
/
Observational_studies
/
Prognostic_studies
/
Risk_factors_studies
/
Screening_studies
Limite:
Adult
/
Aged
/
Aged80
/
Female
/
Humans
/
Male
/
Middle aged
País/Região como assunto:
Asia
Idioma:
En
Ano de publicação:
2019
Tipo de documento:
Article