Curtailed short-term and long-term survival following infection with non-typhoid Salmonella in Israel

Authors


Corresponding author and reprint requests: M. Weinberger, Infectious Diseases Unit, Assaf Harofeh Medical Center, Zerifin 70300, Israel
E-mail: miriw@netvision.net.il

Abstract

Clin Microbiol Infect 2011; 17: 278–284

Abstract

Among bacterial foodborne pathogens, non-typhoid Salmonella enterica (NTS) is a leading cause of death worldwide. This study assessed short-term and long-term mortality following NTS infection in Israel, and evaluated the effects of age, sex, source of isolation and different serotypes on mortality. The source of data was a national registry of NTS isolates submitted to the Salmonella Reference Center, Government Central Laboratories, in Jerusalem, Israel, during 1997–2006. Vital status was derived from the registry of the Israeli Ministry of the Interior. The survival of a cohort of 15 919 patients infected with the top five NTS serotypes was evaluated by calculating age-standardized mortality ratios (SMRs) and by Cox proportional hazards multivariate regressions at three follow-up time intervals: 30 days, 1 year and end of follow-up. The median follow-up time was 6.44 years (mean, 6.21 years; range, 1 day to 10.80 years). The cumulative crude mortality rates at the three time intervals were 0.68%, 1.86% and 4.40%, respectively, corresponding to increased SMRs of 16.95 (95% CI 13.9–20.46), 4.25 (95% CI 3.78–4.76), and 1.83 (95% CI 1.70–1.97), respectively. Cox regressions revealed that increasing age, extraintestinal source of isolation and NTS serotype had significant effects on mortality within all three follow-up intervals. The risk of mortality was increased for serotypes Infantis and Typhimurium, and decreased for serotypes Virchow and Hadar, as compared with serotype Enteritidis. The study revealed curtailed short-term and long-term survival following NTS infection that persisted for many years following detection by culture.

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