ABSTRACT
Background: Infected poultry is one of the most important reservoirs of Salmonella. Aims: The investigation presented here was conducted to examine the occurrence of Salmonella in fecal samples among selected flocks of backyard poultry in Bosnia and Herzegovina (B&H). Methods: Isolation and identification of Salmonella was performed in accordance with BAS EN ISO 6579/AMD 1:2007. When genus Salmonella was confirmed, the determination of the antigenic formula of Salmonella isolates was performed in accordance with BAS CEN ISO/TR 6579-3:2015. After that, Salmonella serotypes were subjected to antibiotic susceptibility testing using EUVSEC sensititre microtiter plates impregnated with different concentrations of antibiotics. At the end, real-time PCR was used to detect extended spectrum ß-lactamases (ESBL) and carbapeneamase encoding genes (bla TEM, bla SHV, bla CTX-M, bla CMY, bla KPC, bla NDM, bla OXA-48, bla VIM and bla GES). Results: Salmonella spp. was detected in pooled feces from four backyards, housed by chickens only. Three isolates were confirmed by slide agglutination as serotype Enteritidis and one as serotype Typhimurium. Antibiotic susceptibility testing by microdilution did not reveal phenotypical resistance among these four isolates. Real-time PCR used to detect ESBL and carbapeneamase encoding genes revealed the bla TEM gene in one S. Enteritidis isolate. Conclusion: Data presented in this study provide further evidence on the circulation of different Salmonella serotypes in backyard poultry in B&H. These findings emphasize the potential role of backyard poultry in the epidemiology of salmonellosis and the risks it poses for keepers, consumers, and general public health.
ABSTRACT
Feral pigeons (Columba livia domestica), which thrive in most European towns and cities, are commonly infected with the zoonotic bacterium Chlamydophila psittaci, the agent of psittacosis (also known as ornithosis) in humans. A number of surveys carried out over the last thirty years across Europe have detected high seropositivity values and high percentages of infection in feral pigeon populations. Overall, when considering data from 11 European countries, seropositivity values to C. psittaci in the sampled populations ranged from 19.4% to 95.6%. In most surveys, the complement fixation test was used, and antibodies were detected in 19.4-66.3% of the samples, with a median of 46.1%. Indirect immunofluorescence and ELISA tests were employed less frequently, but led to the detection of higher percentages of seropositivity (23.7-67.7% and 35.9-95.6%, respectively). Attempts to grow C. psittaci in cell culture or embryonated chicken eggs were successful in 2-42.3% and 0-57.1% of samples, respectively, antigen detection methods were positive in 2.3-40% of samples, while conventional PCR and real-time PCR using different genomic targets detected the organism in 3.4-50% of samples. Twenty-five C. psittaci isolates from pigeons were typed as ompA genotype B (n=14), E (n=10) and E/B (n=1). The huge increase of feral pigeon populations in Europe is a major cause of concern for the detrimental effect of pigeon droppings on environmental hygiene, in addition to the extensive damage due to the fouling of buildings and monuments. The most important pathogenic organism transmissible from feral pigeons to humans is C. psittaci, with 101 cases of disease reported in the literature. Exposure to C. psittaci-contaminated dust, direct contact with pigeons through handling and, to a lesser extent, through pigeon feeding have been identified as hazardous exposures in more than half of the human cases, while loose or transient contacts with feral pigeons have been mentioned in about 40% of the cases. Education initiatives as to the communication of a health risk resulting from contact with pigeons and pigeon excreta should primarily be targeted at individuals who may be exposed to C. psittaci-contaminated dust, such as demolition/construction workers. Recommendations to this category of workers include wearing protective clothes with hoods, boots, gloves and air filter face masks when removing pigeon faeces from roofs, garrets and buildings, especially if working indoors. Monitoring for C. psittaci infections in these workers over time should also be considered. Children should be warned not to handle sick or dead pigeons, and immunocompromised individuals should be advised to carefully limit their contact to feral pigeons. Culling of pigeons by shooting or poisoning is both unethical and ineffective as the place of the killed birds in the population is quickly filled by new juveniles or immigrating birds from neighbouring areas. Pigeon-deterring systems, such as nets and plastic or metal spikes applied to buildings and monuments will prevent their fouling, and the administration of contraceptive drugs may allow size regulation of the pigeon populations. Nevertheless, the measure that will ultimately lead to permanent reduction and will establish healthy sustainable populations is the restriction of indiscriminate feeding by pigeon lovers. The erection of dovecotes and artificial breeding facilities should be considered for providing shelter and a balanced diet to the birds, as well as a chance of interaction for pigeon lovers in a hygienically controlled environment.
