Population-Attributable Risk Estimates for Risk Factors Associated withCampylobacterInfection, Australia

Abstract

multicenter, prospective case-control study involving 1,714 participants >5 years of age was conducted in Australia to identify risk factors for Campylobacter infection. Adjusted population-attributable risks (PARs) were derived for each independent risk factor contained within the fi nal multivariable logistic regression model. Estimated PARs were combined with adjusted (for the >5 years of age eligibility criterion) notifi able disease surveillance data to estimate annual Australian Campylobacter case numbers attributable to each risk factor. Simulated distributions of "credible values" were then generated to model the uncertainty associated with each case number estimate. Among foodborne risk factors, an estimated 50,500 (95% credible interval 10,000-105,500) cases of Campylobacter infection in persons >5 years of age could be directly attributed each year to consumption of chicken in Australia. Our statistical technique could be applied more widely to other communicable diseases that are subject to routine surveillance. F oodborne gastroenteritis is a major public health concern in many countries, including Australia. A recent study estimated that 5.4 million cases (95% credible interval [CrI] 4.0-6.9 million), 15,000 hospitalizations (95% CrI 11,000-18,000), and 80 deaths (95% CrI 40-120) annually are caused by foodborne gastroenteritis in Australia (1). Norovirus, enteropathogenic Escherichia coli, Salmonella spp., and Campylobacter spp. accounted for 88% of the estimated 1.5 million (95% CrI 1.0-1.9 million) cases of foodborne disease caused by known pathogens.Among known foodborne pathogens, Campylobacter spp. are the most frequently reported enteric pathogens in Australia (2). The incidence of Campylobacter infection steadily increased from 1991 through 2001 but has been relatively stable since. In 2005, >15,000 cases were reported in Australia, a crude rate of 113.0/100,000 population. However, because of underreporting, ≈223,000 Campylobacter infections are estimated to occur annually; ≈75% of these are foodborne (3). Most of these infections are sporadic.Case-control studies have identifi ed a range of different risk factors for infection; consumption of chicken is the most frequently reported (4-9). Some of these studies report population-attributable fractions associated with independent risk factors, but no estimates of the total magnitude of infection caused by chicken or other risk factors have yet been reported. Using a multicentered, prospective casecontrol study, we aimed to develop a multivariable logistic regression model that identifi ed independent foodborne and nonfoodborne risk factors for Campylobacter infection for this sample (7) and calculate population-attributable risk (PAR) proportions. These PARs were then combined with annual Campylobacter infection surveillance data to estimate the total number of infections (with associated CrIs) among persons >5 years of age attributable to specifi c risk factors that occur in the community each year in Australia.

Risk attribution ofCampylobacterinfection by age group using exposure modelling

“…8 to 29 . 3 % [13,15,38,39]. Recent source attribution studies based on the multilocus sequence typing method (MLST) from England, Scotland and New Zealand estimated that 50-80 % of human cases were related to the chicken reservoir [37,[40][41][42].…”

Impact of Rurality, Broiler Operations, and Community Socioeconomic Factors on the Risk of Campylobacteriosis in Maryland

“…Although the adjusted odds ratio (AOR) for cooked chicken was lower than that for undercooked chicken, the higher population-attributable risk (PAR) was explained by a higher proportion of exposed case-patients (74.3% reported eating cooked chicken) (Stafford 2008).…”

“…In general, insufficient temperatures and cooking times as well as cross-contamination lead to Campylobacter exposure and thus increased risk of infection. In a multicenter, prospective case-control study conducted by Stafford et al (2008) reported that preventing cross-contamination through washing the cutting board after use with raw chicken (mOR, 0.5; 95% CI, 0.3-0.7) and washing hands after handling raw chicken (mOR, 0.5; 95% CI, 0.4-0.6), were practices associated with a reduced risk of campylobacteriosis .…”

Caracterização molecular de linhagens de Campylobacter coli isoladas de origens diversas

“…Na Austrália, a estimativa é de que ocorram mais de 200.000 casos anualmente (Stafford et al, 2008) e os gastos com infecções entéricas excedem 1,2 bilhões de dólares anualmente (Abelson et al,2006).…”

“…O Campylobacter é a causa mais comum de doença bacteriana veiculada por alimento na Europa, Estados Unidos e alguns outros locais do mundo (Stafford et al, 2008;EFSA, 2015;CDC, 2015) representando um enorme desafio para a saúde e um elevado impacto socioeconômico. Entretanto, reconhecimento do patógeno nas doenças gastrointestinais é dificultado tanto pelas condições de crescimento do microrganismo como pela subnotifição da doença (Jore et al, 2010;Havelaar et al, 2013;EFSA, 2015).…”