Longitudinal analysis of Giardia duodenalis assemblages in animals inhabiting drinking water catchments in New South Wales and Queensland – Australia (2013–2015)

Zoonotic Cryptosporidium and Giardia in marsupials—an update

“…It is also possible that marsupials may be acquiring assemblage A from co-grazing with other animals in catchments. For example, in the study by Zahedi et al ( 2020 ), assemblage AI sequences determined at the gdh locus in kangaroos were identical to sheep-derived sub-assemblage AI isolates from the same catchment. Evidence to date suggests that G. duodenalis sub-assemblage AI is largely confined to animals and is rarely found in humans (Klotz et al 2022 ).…”

“…There has been one report of assemblage C in eastern gray kangaroos (Ng et al 2011 ) and two reports of assemblage D in eastern gray kangaroos (Ng et al 2011 ) and a single quenda (Hillman et al 2019 ). Assemblage E has been reported in a single quenda (Thompson et al 2010 ), eastern gray kangaroo (Zahedi et al 2020 ), and a red-necked wallaby (Zou et al 2022 ). There has also been one report of an assemblage C and D mixture in three quendas (Thompson et al 2010 ).…”

“…Similarly, the identification of the livestock-associated assemblage E in marsupials, is also likely due to mechanical carriage from co-grazing pastures with livestock. Little is known about cyst shedding in marsupials but mean cyst shedding per gram of faeces of 7.8 × 10 3 (median = 6 × 10 3 ) (range 1 × 10 2 –2.2 × 10 4 ) was reported in eastern gray kangaroos using qPCR (Zahedi et al 2020 ).…”

“…The dominance of the zoonotic G. duodenalis assemblages A and B in marsupials may be due to spill-back from humans as interactions between humans and small marsupials are common and include humans offering food (Hillman and Thompson 2016 ; Hillman et al 2017a ; Hillman et al 2017b ; Hillman et al 2019 ). The few subtyping studies conducted have detected the largely animal-associated sub-assemblage AI in a common planigale (Thompson et al 2010 ), brushtailed rock-wallabies (Vermeulen et al 2015b ), a single eastern gray kangaroo, and wombat in a Melbourne catchment (Koehler et al 2016b ) and in eastern gray kangaroos in Sydney catchments (Ng et al 2011 ; Zahedi et al 2020 ). It is also possible that marsupials may be acquiring assemblage A from co-grazing with other animals in catchments.…”

Variation in the Structure and Composition of Bacterial Communities within Drinking Water Fountains in Melbourne, Australia

“…Research investigating microorganisms within drinking water in Australia has addressed environments including recreational parks [28], groundwater bores [29], private water tanks [30,31], water catchments [32][33][34] and DWDSs [35] and has often focussed on specific pathogenic microorganisms including Escherichia coli [35], Cryptosporidium and Giardia [33,36] and nontuberculous Mycobacterium species [37][38][39] rather than investigating the composition of the entire community via high-throughput sequencing technologies. Clearly, an appropriate investigation into the identity and relative abundance of bacteria residing in water sourced from point-of-use locations (fountains) is necessary.…”