Potential Role of Birds in the Epidemiology of Coxiella burnetii, Coxiella-like Agents and Hepatozoon spp.

Abstract

Birds may be involved in the epidemiology of infectious and/or parasitic diseases which affect mammals, including humans. Q fever, caused by Coxiella burnetii, is an important zoonosis causing economic losses mainly due to pathologies induced in ruminants. Even though birds are known to be potential reservoirs of C. burnetii, their role in the epidemiological cycle of the pathogen is not completely verified. In recent years, new bacteria identified as Coxiella-like agents, have been detected in birds affected by different pathologies; the potential role of these bacteria as pathogens for mammals is not currently known. Hepatozoon spp. are haemoprotozoa, causing arthropod borne affections within several vertebrate classes. The infection of vertebrate host develops after ingestion of the arthropod final hosts containing oocysts; different tissues and blood cells are then colonized by other parasite stages, such as merozoites and gamonts. In avian hosts, there are several recognized Hepatozoon species; however, their life cycle and pathogenicity have not been fully elucidated. Referring to a carrier role by avian species and their ticks in the epidemiology of canine hepatozoonosis, the only clinically relevant affection caused by this parasite genus, they would act as carriers of infected ticks and, when Hepatozoon americanum is involved, as paratenic hosts, as well.

Description of an intramonocytic haemoparasite, Hepatozoon lainsoni sp. nov. (Apicomplexa: Adeleorina: Hepatozoidae), infecting Ameiva ameiva lizard (Reptilia: Squamata: Teiidae) in northern Brazil

“…To date, species of Hepatozoon have been reported mainly infecting erythrocytes of reptiles. However, other species infecting mammals and birds are found mainly infecting leucocytes (Smith, 1996 ; Godfrey et al ., 2011 ; Ebani and Mancianti, 2022 ). This study provides molecular analysis and morphological and morphometric descriptions of the blood forms and tissue stages of H. lainsoni sp.…”

Vertical organization of microbial communities in Salineta hypersaline wetland, Spain

“…Furthermore, members of the Coxiella genus have been detected in seawater associated with urban wastewater inputs (Fonti et al, 2021). The farming activities around the Salineta wetland and the presence of migratory birds represent potential sources of Coxiella since it has been detected in the feces of livestock (Mcquiston and Childs, 2002) and wild birds (Ebani and Mancianti, 2022).…”

Pacific Gulls (Larus pacificus) as Potential Vectors of Coxiella burnetii in an Australian Fur Seal Breeding Colony

“…With 47.1% of all cloacal swabs being positive for C. burnetii DNA, there is a substantial probability that PG could disseminate the organism throughout the marine and coastal environments. The detectable presence of C. burnetii in the faeces of birds in other studies has been linked to the spread of C. burnetii into the environment through avian vectors [ 15 ]. Faecal shedding could further be prolonged in birds that are subclinically infected.…”

“…Additionally, it was hypothesized that PGs breeding on Seal Island (SI), a nearby island where (despite the name) there is no AusFS breeding colony, would not have detectable C. burnetii . Considering that the role of birds in the epidemiology of C. burnetii is poorly understood [ 15 ], it is important to have a better grasp of the ecological role of the PG as a potential vector for spreading C. burnetii in marine mammal populations. Whether this pathogen could be a disease risk to the gulls themselves or pose a risk of being spread as a zoonotic infection are important considerations not investigated in this study.…”