Campylobacter spp. as a cause of foodborne infections in humans

Saturday, October 3, 2015

In our August issue of Better Pork, veterinary consultant Ernest Sanford reviewed the effects of salmonella in pigs and humans. Here, he discusses another bacterial organism that can cause serious health problems for humans. However, poultry is the primary source

by ERNEST SANFORD

P reviously, I charted the path of Salmonella foodborne infection in humans, contracted from eating pork infected with Salmonella spp. I also pointed out that pork became the number one source of Salmonella food poisoning in people after the poultry industry had spent several decades in "cleaning up" poultry meat and eggs so that they were no longer the leading source of Salmonella infections in people.  

Campylobacter spp. is another bacterial organism causing foodborne infections in humans and hence another example of a zoonotic infection. In this case, however, the pig is a mere bystander as a source of Campylobacter foodborne infection in humans. Here's why.

Campylobacter spp. infections in humans are caused primarily by Campylobacter jejuni, which is a common inhabitant in the intestines of poultry. It is almost nonexistent in pigs. Virtually 100 per cent of pigs (and similarly 100 per cent of all farm animals such as cattle, sheep and goats) harbour Campylobacter coli, a related but different Campylobacter spp., in their intestines.  C. coli is infrequently identified or associated with infections or disease in humans.

Campylobacter spp. is the most commonly isolated bacterial pathogen from people with diarrhea worldwide, even more common than infections with Salmonella spp. C. jejuni, the most common isolate of the Campylobacters in human diarrhea cases, accounts for more than 99 per cent of the Campylobacter spp. isolated. C. coli is isolated in less than one per cent of Campylobacter spp. diarrhea cases in humans.

Campylobacter jejuni infection causes severe diarrhea in humans and is one of the most common causes of human gastroenteritis worldwide. Infection with C. jejuni usually results in enteritis, which is characterized by abdominal pain, diarrhea, fever and malaise. The symptoms usually persist for between 24 hours and a week, but may last longer. Diarrhea can vary in severity from plain loose stools to bloody stools.

The disease is usually self-limiting. However, it does respond to antibiotics. Severe or prolonged cases (those with accompanying fevers, blood in stools) may require more aggressive antibiotic therapy, using ciprofloxin, erythromycin or azithromycin. About 90 per cent of cases respond to ciprofloxacin treatment. Fluid and electrolyte replacement therapy may be required for serious cases.

Improperly prepared poultry products contaminated with the offending C. jejuni bacterium are a common source of Campylobacter gastroenteritis in humans. BP

S. Ernest Sanford, DVM, Dip Path, Diplomate ACVP is a swine veterinary consultant based in London