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Campylobacter jejuni and Campylobacter coli infections are the leading cause of foodborne gastroenteritis in high‐income countries. Campylobacter colonizes a variety of warm‐blooded hosts that are reservoirs for human campylobacteriosis. The proportions of Australian cases attributable to different animal reservoirs are unknown but can be estimated by comparing the frequency of different sequence types in cases and reservoirs. Campylobacter isolates were obtained from notified human cases and raw meat and offal from the major livestock in Australia between 2017 and 2019. Isolates were typed using multi‐locus sequence genotyping. We used Bayesian source attribution models including the asymmetric island model, the modified Hald model, and their generalizations. Some models included an "unsampled" source to estimate the proportion of cases attributable to wild, feral, or domestic animal reservoirs not sampled in our study. Model fits were compared using the Watanabe–Akaike information criterion. We included 612 food and 710 human case isolates. The best fitting models attributed >80% of Campylobacter cases to chickens, with a greater proportion of C. coli (>84%) than C. jejuni (>77%). The best fitting model that included an unsampled source attributed 14% (95% credible interval [CrI]: 0.3%–32%) to the unsampled source and only 2% to ruminants (95% CrI: 0.3%–12%) and 2% to pigs (95% CrI: 0.2%–11%) The best fitting model that did not include an unsampled source attributed 12% to ruminants (95% CrI: 1.3%–33%) and 6% to pigs (95% CrI: 1.1%–19%). Chickens were the leading source of human Campylobacter infections in Australia in 2017–2019 and should remain the focus of interventions to reduce burden. [ABSTRACT FROM AUTHOR]

Reptiles are carriers of Salmonella and can intermittently shed bacteria in their faeces. Contact with snakes and lizards is a source of human salmonellosis. Here, two populations of reptiles, wild and captive were surveyed for Salmonella. One hundred thirty wild‐caught reptiles were sampled for Salmonella including 2 turtle, 9 snake and 31 lizard species. Fifty‐two of 130 (40%) animals were Salmonella positive: one of 5 (20%) turtles, 7 of 14 (50%) snakes and 44 of 111 (39.6%) lizards. One hundred twenty‐two reptiles were sampled from a zoo collection including 1 turtle, 6 tortoise, 9 lizard, 14 snake and 1 crocodile species. Forty‐two of 122 (34.4%) captive reptiles sampled were Salmonella positive. Salmonella was most commonly isolated from lizards and snakes. Fifteen serotypes were identified from zoo and 19 from wild‐caught reptiles and most were members of subspecies enterica (I), salamae (II), arizonae (IIIa) or diarizonae (IIIb). Antimicrobial susceptibility testing was conducted on all Salmonella isolates; only two exhibited resistance, a Salmonella subsp. (II) ser. 21:z10:z6 (Wandsbek) isolate cultured from a wild‐caught reptile and a Salmonella Typhimurium DT120 isolated from a captive snake. The invasive capacity of reptile‐associated Salmonella strains into cultured human intestinal epithelial (Caco2) and mouse macrophages cell lines (J774A.1) was also investigated. All isolates were invasive into both cell lines. Significant (P ≤ 0.001) variability in invasiveness into polarized Caco2 cells was observed. Salmonella Eastbourne exhibited the highest invasiveness into Caco2 cells and Salmonella Chester the lowest, with mean per cent recoveries of 19.99 ± 0.32 and 1.23 ± 0.30, respectively. Invasion into J774A.1 macrophages was also variable but was not significant. Salmonella subsp. II ser. 17:g,t:‐ (Bleadon) exhibited the highest invasiveness into J774A.1 with a mean per cent recovery of 10.19 ± 0.19. Thus, reptile‐associated Salmonellae are likely to have different capacities to cause disease in humans. [ABSTRACT FROM AUTHOR]

The article presents a retrospective analysis of consecutive microbiologically confirmed enteric fever isolates. The researchers aimed to determine incidence and trends in antibiotic resistance in Australian Salmonella enterica subspecies enterica serovars Typhi (S. Typhi) and Paratyphi (S. Paratyphi) isolates from 1985 to 2010. The analysis found that nalixidic acid resistance has become widespread in enteric fever isolates from the Indian subcontinent and some parts of South-East Asia.

The article discusses "Salmonella" Rubislaw gastroenteritis linked to a pet eastern bearded dragon (Pogona barbata). It describes the case of a four-month-old girl brought to the Australian Capital Territory hospital emergency department in August 2009 with fever, vomiting and bloody diarrhoea with rectal prolapse. Stool culture and serotyping indicated "Salmonella enterica" serotype Rubislaw. After four days of treatment, the child was discharged from the hospital. Salmonellosis is a notifiable infection in all Australian states and territories.