Archive

Antimicrobial resistance is a problem that arises from the adaptation of pathogens and can be a serious problem in the management of life-threatening bacterial infections, particularly because of its public health significance through the products of food-producing animals. Pigeons come into contact with humans both as food producing animals and in urban environments, and their role as reservoirs of resistance is particularly important. The literature on the assessment of resistance in pigeons is poor, although a number of antibiotics not approved for use in poultry are used for their treatment.

In our study, we were the first in Hungary to assess the antibiotic susceptibility of bacteria isolated from pigeons in a representative manner by region from a total of 22 pigeon farms, using minimum inhibitory concentration (MIC) determinations for 294 isolates. After a preliminary online and then face-to-face questionnaire survey with pigeon fanciers, it was found that most of them (66.7%) keep racing pigeons. 46.7% of the respondents keep 51-100 flocks and 33.3% 101-500 flocks. Fluoroquinolones (13%), colistin (5%) are also used to a significant extent among the substances of critical importance for public health. 66.7% of pigeon fanciers do not carry out susceptibility testing and only 6.7% do so regularly.

Escherichia coli strains (167) showed susceptibility to ceftriaxone, enrofloxacin and colistin based on MIC50 values; 49% resistance to ceftriaxone, 52% resistance to enrofloxacin and 31% resistance to colistin were detected. Staphylococcus strains (74) were found to be susceptible to amoxicillin and ceftriaxone, but resistance to the critically important antibiotics enrofloxacin (92%) and vancomycin (78%), which is used almost exclusively in human medicine, is of concern. Enterococcus strains (53) were susceptible to imipenem, showing 91% resistance to enrofloxacin and 66% resistance to vancomycin. Grouping strains by population size, smaller populations showed more favourable susceptibility data. By type of use, mixed use strains were the most susceptible to antibiotics, followed by ornamental pigeons.

The high levels of resistance to critically important antibiotics are worrying and are a consequence of often unjustified antibiotic use. In the future, there is a need for more widespread and regular surveys of pigeon fanciers and the dissemination of knowledge on correct antibiotic use to them.