Screening for several potential pathogens in feral pigeons (Columba livia) in Madrid

Abstract

BackgroundPathogens with the zoonotic potential to infect humans, such as Campylobacter jejuni, Campylobacter coli and Chlamydophila psittaci, can be found in feral pigeons (Columba livia). Given the high density of these birds in the public parks and gardens of most cities, they may pose a direct threat to public health.MethodsA total of 118 pigeons were captured in three samplings carried out in 2006-2007 in public parks and gardens in Madrid, Spain. Standard haematological and morphological analyses were carried out on the pigeons. PCR was used to screen for the presence of Campylobacter jejuni, C. coli and Chlamydophila psittaci. Positive samples were confirmed by DNA sequencing.ResultsThe analyses demonstrated a high prevalence of Chlamydophila psittaci (52.6%) and Campylobacter jejuni (69.1%) among the birds captured. In contrast, Campylobacter coli was rarely detected (1.1%).ConclusionsPigeons in Madrid can carry Chlamydophila psittaci and Campylobacter jejuni. They may be asymptomatic or subclinical carriers of both pathogens.

Microbiological and parasitological survey of zoonotic agents in apparently healthy feral pigeons

“…However, the positive results were relevant as the pigeons did not show any clinical signs, in accordance with data reported by Vazquez et al (2010), thus supporting the hypothesis that they may act as asymptomatic reservoirs of C. psittaci or other chlamydial species. Moreover, in the absence of clinical signs, the shedding of chlamydia is generally intermittent making it difficult to detect (Tomić et al 2013).…”

“…Casanovas et al (1995) demonstrated that C. jejuni was the most frequently isolated bacterium in 105 pigeons (26.2%) with a greater incidence in the districts of the city of Barcelona regardless of seasonal variation. Vazquez et al (2010) also detected a high prevalence of C. jejuni and low prevalence of C. coli, as in our study. However, despite the frequent isolation of Campylobacter spp.…”

“…Cryptococcus neoformans, Candida albicans, and Chlamydophila psittaci seem to be the most widespread zoonotic agents in the pigeon populations that reside in cities worldwide (Heddema et al 2006, Magnino et al 2009, Tomić et al 2013). Epidemiological surveys for C. psittaci carried out on pigeons across Europe during the last thirty years detected high seropositivity and high prevalence in feces (Heddema et al 2006, Magnino et al 2009, Vazquez et al 2010), although differences were observed among the diagnostic procedures used and the epidemiological conditions found in various studies. However, the presence of zoonotic organisms in feral pigeons does not necessarily cause disease in man, since several other factors such as the transmission route, the infectious dose, the immune status of the people involved and the closeness of contact strongly influence the possibility of infection (Haag-Wackernagel and Moch 2004).…”

Campylobacter in the environment: A major threat to public health

“…Similarly, direct plating onto selective media has been frequently used for the detection of campylobacters in avian/animal fecal samples and/or cecal contents [9,11,66]. Although direct plating of fecal materials on Campylobacter selective agar plates has been successfully employed in detecting the organism in human and birds/animal fecal samples, it might guarantee a high recovery rates of campylobacters particularly from avian and animal origin or might result in failure to detect the organism in feces [67,68], therefore, incubating fecal samples in selective enrichment broth prior to selective plating potentially increase the detection of campylobacters [5]. Indeed, the incubation of avian/animal fecal samples in enrichment broth prior to selective plating was successfully employed in detecting Campylobacter species [10,16,[69][70][71].…”

O pombo (Columba livia) como agente carreador de Salmonella spp. e as implicações em saúde pública

“…Dessa forma, objetivou-se realizar um levantamento acerca da participação do pombo doméstico na possível disseminação de Salmonella spp. Bale, 1991), e seu contato próximo com os seres humanos pode representar risco à saúde pública (Vázquez et al, 2010), pois desempenham um importante papel na epidemiologia de doenças entéricas em seres humanos (Skirrow, 1991).…”