ABSTRACT
We aimed to estimate influenza vaccine effectiveness (VE) against laboratory-confirmed influenza during three influenza seasons (2010/11 to 2012/2013) in Spain using surveillance data and to compare the results with data obtained by the cycEVA study, the Spanish component of the Influenza Monitoring Vaccine Effectiveness (I-MOVE) network. We used the test-negative casecontrol design, with data from the Spanish Influenza Sentinel Surveillance System (SISS) or from the cycEVA study. Cases were laboratory-confirmed influenza patients with the predominant influenza virus of each season, and controls were those testing negative for any influenza virus. We calculated the overall and age-specific adjusted VE. Although the number of patients recorded in the SISS was three times higher than that in the cycEVA study, the quality of information for important variables, i.e. vaccination status and laboratory results, was high in both studies. Overall, the SISS and cycEVA influenza VE estimates were largely similar during the study period. For elderly patients (> 59 years), the SISS estimates were slightly lower than those of cycEVA, and estimates for children (014 years) were higher using SISS in two of the three seasons studied. Enhancing the SISS by collecting the date of influenza vaccination and reducing the percentage of patients with incomplete information would optimise the system to provide reliable annual influenza VE estimates to guide influenza vaccination policies.
Subject(s)
Influenza A Virus, H1N1 Subtype/immunology , Influenza Vaccines/administration & dosage , Influenza Vaccines/immunology , Influenza, Human/prevention & control , Sentinel Surveillance , Adolescent , Adult , Aged , Aged, 80 and over , Case-Control Studies , Child , Child, Preschool , Female , Humans , Infant , Infant, Newborn , Influenza A Virus, H1N1 Subtype/classification , Influenza A Virus, H1N1 Subtype/isolation & purification , Influenza, Human/epidemiology , Influenza, Human/virology , Male , Middle Aged , Outcome Assessment, Health Care , Spain/epidemiology , Vaccination/statistics & numerical data , Young AdultABSTRACT
A second-generation surveillance system of people infected with human immunodeficiency virus (HIV) has been implemented in Spain. Behavioural and clinical data were collected between 2002 and 2011 through an annual one-day, cross-sectional survey in public hospitals, including all in- and outpatients receiving HIVrelated care on the survey day. Mean age increased over time (from 38.7 years in 2002 to 43.8 years in 2011) and 68.4% of the 7,205 subjects were male. The proportion of migrants increased from 6.1% to 15.9%, while people who inject or used to inject drugs (PWID and Ex-PWID) decreased and men who have sex with men (MSM) and heterosexuals increased. Unprotected intercourse at last sex increased among MSM and PWID/Ex-PWID. Patients receiving antiretroviral treatment increased significantly from 76.0% to 88.2% as did those with CD4 T-cell counts ≥350 (from 48.2% to 66.9%) and viral copies <200 (from 47.0% to 85.2%). HIV-infected people with hepatitis C virus RNA decreased from 36.0% in 2004 to 29.9% in 2011, while those with HBsAg remained stable at around 4.4%. Implementation of a low-cost, sustainable system for second-generation surveillance in people living with HIV is feasible. In Spain, the information obtained has helped to define and refine public health policy and document treatment effectiveness.
Subject(s)
HIV Infections/epidemiology , Health Behavior , Hepatitis C/epidemiology , Population Surveillance/methods , Sexual Behavior , Substance Abuse, Intravenous/epidemiology , Adult , Anti-Retroviral Agents/therapeutic use , CD4 Lymphocyte Count , Cross-Sectional Studies , Female , HIV Infections/drug therapy , HIV Infections/transmission , Health Surveys , Hepatitis C/transmission , Heterosexuality/statistics & numerical data , Homosexuality, Male/statistics & numerical data , Hospitals, Public , Humans , Male , Middle Aged , Socioeconomic Factors , Spain/epidemiologyABSTRACT
Adjusted early estimates of the 2013/14 influenza vaccine effectiveness (VE) in Spain for all age groups was 35% (95% CI: -9 to 62), 33% (95% CI: -33 to 67) and 28% (95% CI: -33 to 61) against any influenza virus type, A(H1N1)pdm09 and A(H3N2) viruses, respectively. For the population targeted for vaccination, the adjusted VE was 44% (95% CI: -11 to 72), 36% (95% CI: -64 to 75) and 42% (95% CI: -29 to 74), respectively. These preliminary results in Spain suggest a suboptimal protective effect of the vaccine against circulating influenza viruses.
Subject(s)
Influenza A Virus, H1N1 Subtype/immunology , Influenza A Virus, H3N2 Subtype/immunology , Influenza Vaccines/administration & dosage , Influenza, Human/prevention & control , Outcome Assessment, Health Care , Adolescent , Adult , Aged , Aged, 80 and over , Case-Control Studies , Child , Child, Preschool , Female , Humans , Infant , Influenza A Virus, H1N1 Subtype/genetics , Influenza A Virus, H1N1 Subtype/isolation & purification , Influenza A Virus, H3N2 Subtype/genetics , Influenza A Virus, H3N2 Subtype/isolation & purification , Influenza, Human/epidemiology , Influenza, Human/virology , Logistic Models , Male , Middle Aged , Population Surveillance , Spain/epidemiology , Vaccination , Young AdultABSTRACT
We present early estimates of influenza vaccine effectiveness (VE) in the population targeted for vaccination, during 25 December 2011 to 19 February 2012. The adjusted VE was 55% (95% CI: 3 to 79) against any type of influenza virus and 54% (95% CI: 1 to 79) against influenza A(H3N2) virus. This suggests a moderate protective effect of the vaccine in the targeted population in a late influenza epidemic with limited match between vaccine and circulating strains.
