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Campylobacter spp

Campylobacter spp. was isolated from human stools first in 1972. Since then, the development of selective media demonstrated the Campylobacter spp. thermophilic primarily C. jejuni and C. coli are frequent in human infections, one of the leading causes of acute diarrhea in humans, besides being in other infections. In human infections, the species found are: C. jejuni (80-90%), C. coli (7%), C. lari, C. hyointestinalis and C. upsaliensis (1%). They can also cause enteritis and abortions in some animals. Other animals are asymptomatic carriers and act as a reservoir of this organism. In animals it has a high prevalence in poultry species (40-100%).

Thermophilic Campylobacter species are: C. jejuni and C. coli (urease positive thermophilic), C. lari and C. upsaliensis.

C. jejuni is in most animal reservoirs is the predominant species isolated chicken and cattle.

Some species tend to be associated with host animals:

·         C. coli, C. hyointestinalis, C. mucosalis in intestine of pigs.

·         Upsaliensis C. and C. helveticus predominant in dogs and cats.

·         C. fetus subsp. fetus in intestinal tract of cattle and sheep.

·         C. lanienae in feces of cattle.

Wild birds are an important reservoir of Campylobacter spp. including urease positive thermophilic C. jejuni and C. lari.

The natural habitat of most species of Campylobacter is the gut of birds and other warm - blooded animals, which in most no symptoms.

Epidemiology

Campylobacter can penetrate into the medium, including drinking water through the feces of animals or humans infected. Although they can not grow in the environment, they can survive in the environment for several weeks at 4 ° C.

The major vehicle for human infection is meat broiler either by eating improperly this cooked meat or cross - contamination of ready meals.

For epidemiological control the following problems: 1) is a zoonotic disease transmitted from chickens and other birds in which no symptoms; 2) methods available for sampling and testing for detection and quantification give variable results so the results of epidemiological studies follow are not comparable; 3) Unlike other pathogenic little it is known about its survivability under usual conditions of food processing .; 4) the belief that thermophilic Campylobacter were sensitive to environmental conditions outside the host are not supported with the epidemiological evidence.

Microbiological methods for detection

They were designed many culture media for the isolation of Campylobacter, most of them including various antimicrobials which act as inhibitors accompanying microbial flora.

The Campylobacter spp. are very demanding and antimicrobial agents incorporated into the selective media inhibit the growth of some species as C. upsaliensis, C. hyointestinalis and C. fetus.

Conventional culture methods are slow and tedious, requiring 1 to 2 days of culture in enrichment media, plating to obtain isolated colonies, and, subsequent culture on selective media for the isolation and then after at least 2 other days for biochemical characterization.

Therefore, detection by culture methods do not provide a true measure of the frequency and the diversity of species in different hosts and their products.

PCR testing can provide a more accurate description of the prevalence of campylobacter associated cattle. However the presence of inhibitors of the PCR test in feces is an important obstacle which limits the usefulness of the PCR test. Some inhibitors as bile salts, degradation of hemoglobin, polysaccharides, polyphenols derived from plants, ...

Tests in IVAMI

·      Detection by isolation by culturing in selective media from stool samples, meat breaths, water, clinical samples of other types, etc.

·         Detection by genomic PCR tests from any human, animal or food sample.