2002/01/31 by Clint Tan Chee Leong, Michael J. Seiler, Mark A. Lane · 5 citations
Economics, Econometrics and Finance · Medicine · #Financial Markets and Investment Strategies #Medicine #Hazard ratio #Confidence interval #Demography #Vaccination #Pediatrics #Index case #Proportional hazards model #Transmission (telecommunications) #Disease #Internal medicine #Immunology
paper · doi:10.3905/jwm.2002.320422
published in The journal of wealth management 4(4), 8-23 (Euromoney Institutional Investor)
openalex publication_date 2002/01/31 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/01
<b>Background:</b> Influenza transmission in households is a subject of renewed interest, as the vaccination of children is currently under debate and antiviral treatments have been approved for prophylactic use. <b>Aims:</b> To quantify the risk factors of influenza transmission in households. <b>Design of study:</b> A prospective study conducted during the 1999 to 2000 winter season in France. <b>Setting:</b> Nine hundred and forty-six households where a member, the index patient, had visited their general practitioner (GP) because of an influenza-like illness were enrolled in the study. Five hundred and ten of the index patients tested positive for influenza A (subtype H3N2). A standardised daily questionnaire allowed for identification of secondary cases of influenza among their household contacts, who were followed-up for 15 days. Of the 395 (77%) households that completed the questionnaire, we selected 279 where no additional cases had occurred on the day of the index patient9s visit to the GP. <b>Methods:</b> Secondary cases of influenza were those household contacts who had developed clinical influenza within 5 days of the disease onset in the index patient. Hazard ratios for individual clinical and demographic characteristics of the contact and their index patient were derived from a Cox regression model. <b>Results:</b> Overall in the 279 households, 131 (24.1%) secondary cases occurred among the 543 household contacts. There was an increased risk of influenza transmission in preschool contacts (hazard ratio [HR] = 1.85, 95% confidence interval [CI] = 1.09 to 3.26) as compared with school-age and adult contacts. There was also an increased risk in contacts exposed to preschool index patients (HR = 1.93, 95% CI = 1.09 to 3.42) and school-age index patients (HR = 1.68, 95% CI = 1.07 to 2.65), compared with those exposed to adult index cases. No other factor was associated with transmission of the disease. <b>Conclusion:</b> Our results support the major role of children in the dissemination of influenza in households. Vaccination of children or prophylaxis with neuraminidase inhibitors would prevent, respectively, 32–38% and 21–41% of secondary cases caused by exposure to a sick child in the household.