Those who are older, Hispanic or pregnant have a higher risk for
listeriosis in the United States, according to investigators from the CDC and
FDA, who recommend further research to better understand the effects of age and
underlying conditions on listeriosis risk in this population.
Previous research indicates that, more than for most other
foodborne pathogens, a consumers susceptibility is the leading risk
factor for listeriosis, Regis Pouillot, PhD, DVM, of the FDA, told
Infectious Disease News. This study not only confirms, but also
quantifies the higher risk of listeriosis among different subpopulations.
Age, pregnancy status and ethnicity were evaluated to identify the RR of
listeriosis among 762 cases identified between 2004 and 2009 that were included
in the Foodborne Diseases Active Surveillance Network; 64 cases were excluded
from the analysis.
The RR for nonpregnant women aged 45 to 59 years was 4.7 (95% CI,
3.3-6.8) vs. 53.8 among those aged older than 85 years (95% CI, 37.3-78.9). In
addition, when compared with non-Hispanics, the RR for listeriosis was higher
among Hispanics (RR=1.8; 95% CI, 1.3-2.5).
When the researchers compared the RR between pregnant and nonpregnant
women, the risk was highest among pregnant women (RR=114.6; 95% CI,
68.9-205.1). Overall, the RR was higher for Hispanic women compared with
non-Hispanic women and increased during the study period: from 2004 to 2006,
the RR was 1.9 (95% CI, 1-3.3) and from 2007 to 2009, the RR was 4.8 (95% CI,
Additional data are currently being gathered by the CDC to better
characterize the impact of various underlying conditions, such as cancer,
diabetes and immunosuppressive therapy, on the increased risk with age,
Pouillot said. These data will help to inform risk-assessment research at
the FDA, which in turn informs risk-management decisions.
Pouillot R. Clin Infect Dis. 2012;54:s405-S410.
The researchers report no relevant financial disclosures.