Campylobacteriosis (Traveler’s Diarrhoea)

Campylobacteriosis (Traveler’s Diarrhoea) is a venereal disease causing infertility, repeat breeding, abortion in early stages of pregnancy, and gastrointestinal problems in cattle, sheep, goats and human beings.

Etiology

• Campylobacter and Arcobacter are now included in the family campylobacteriaceae.
• It has been identified that C.jejuni and C.coli is responsible for >95% of campylobacter infections.
• However, C. upsaliensis, C.lari, C. fetus subspecies fetus, C.fetus subspecies venerealis, C. jejuni have been isolated from human patients with diarrhoea.

• Campylobacter is a small gram negative, micro aerophilic, curved to spiral, rods shaped organism that possess a single polar flagellum.
• They have a characteristic corkscrew, rapid carting and or spinning kind of motility.

Epidemiology

Prevalence of infection

• Outbreaks occurs following introduction of infected bulls or cows into the breeding farms and the presence of increased number of estrus cows in the herd.
• Prevalence have reported in human and poultry but the rate of prevalence varies between countries and regions.
• Prevalence mostly seen in dairy cattle.

Predisposing factors

• Contaminated soil and housing environment
• Introduction of infected carriers
• Transport

Source of infection

• Both young and older bulls have been identified as carriers for upto 18 weeks post infection, but older bulls are remaining as permanent carrier that has been attributed to the highest proliferation of C. fetus in the major site of epithelial crypts of the penis, in contrast, C. fetus concentration is very less in preputial fluid.
• Environment: soil, air, water (swimming water, recreational streams, disinfected effluent, puddles, pond water, surface waters), protozoans, wild birds and wildlife
• Environmental contamination of pen, farm equipment.
• Infected eggs, hatchery waste and poultry house litters.

Transmission

• Spread of infection occurs during coitus from infected cow to bull and vice versa.
• Bulls below five years of age rarely infected.

Host Affected

• Cattle is highly susceptible for venereal campylobacteriosis as compared to sheep and goats.
• Sheep and goats affected by reproductive and gastrointestinal form of campylobacteriosis.
• Human affected by gastrointestinal and nervous form of infection.
• Poultry species are affected mainly with gastrointestinal form of infection.
• Domestic and farm animals including pet dogs and cats, wild birds, farm animals (cattle, sheep, pigs, ducks, turkeys)
• Insects (beetles, flies)
• Rodents (mice, rats)

Pathogenesis

Naturally infected bulls transmit C.fetus subspecies venerealis from one female to another, without any quality changes in semen and breeding ability.

The organism establishes infection in the prepuce.

In cows, in cervico-vaginal area, during estrus, no uterine infection develop, due to presence of abundant neutrophils in the uterus at the time of estrus which prevent colonization of the organism within the uterus.

But in the later stage of the estrus the organism invade and establish the infection in the uterus.

Within 10 days following mating, the organism establishes infection in the mucous membrane of the vagina and cervix which leads to mild vaginitis, cervicitis and endometritis.

Due to the presence of abundant neutrophils during the estrous period, spread of the infection is limited to endometrium until the progesterone phase. At this phase adhesion molecules keep the organism localised in the intra-luminal location, so that in the absence of IgA/IgG2, no opsonization of the organism occurs.

However, during di-oestrus period, neutrophils are fewer and so the organism multiply in the reproductive tract and colonize the C.fetus subsp. venerealis in the endometrium.

The pathogenic nature of the organism increased because of a protective surface antigen or anti-phagocytic macrocapsule comprising a paracrystalline array of (surface array protein) protein which stimualtes IgA, IgG, and IgM, following colonization of campylobacter.

IgG is an important agglutinin/opsonin secreted by the uterus of convalescent animals helps neutrophils and macrophages in the phagocytic process, while IgA found primarily in the cervico-vaginal mucus, immobilize C. fetus subsp. venerealis within this organ of convalescent animals which leads to carrier status.

After conception if cows infected it may carry the organism. As there is insufficient stimulation of antigen the organism is restricted to the epithelial surface.

Antigenic variation of the bacteria might be an additional factor enhancing the persistence of the carrier status in bulls as well as in cows.

Clinical Signs

Bovine campylobacteriosis

Bovine campylobacteriosis is mainly characterized by infertility, repeat breeding, early embryonic deaths, increased conception rate and abortion in the late pregnancy.

Reddening of cervix and extension of mild mucopurulent exudate from uterus into cervix and vagina occurs

In contrast, infected heifers which have natural immunity quickly conceive, but remain as carrier for months.

Subacute or chronic form

Moderate problems may develop but resistant to infection due to an anamnestic immune response, where as the newly introduced. susceptible females develop more acute form of disease.

Highly susceptible animals show high prevalence and cause abortion.

In Poultry

• C. jejuni in poultry is invasive in nature.
• Watery droppings, soiling of vent and feathers.
• In severe cases blood spots in droppings.
• Dehydration, depression, and death noticed.

Zoonosis

• In India, Campylobacter fetus subspecies jejuni was isolated from 14.8% of healthy population in rural South India.
• It produce travellers diarrhoea in human beings.

Necropsy Findings

• Diffuse and mild infiltration with inflammatory cells, desquamation of the superficial epithelium observed.
• Periglandular fibrosis is restricted to cystic glands.
• The endometritis has been identified by the presence of infiltrated plasma cells and foci of lymphocytes in the stroma. Not much abnormalities in the prepuce and penile mucosa of the bulls.

Diagnosis

• Based on clinical signs and necropsy findings.
• Isolation and identification of organism.
• Serum agglutination, cervical mucus agglutination, fluorescent antibody and culture tests have been used, however each tests has certain limitations.

Serum agglutination (SA) test

Serum agglutination (SA) test is not a reliable test and and antibodies are rarely found in the blood stream.

Cervical mucus agglutination test (CMA)

Cervical mucus agglutination test (CMA) is a convenient and accurate method for herd level bovine campylobacteriosis, though this test is widely used there is a chances for false positive (Metestral bleeding or rough manipulation of the vagina during collection) and false negative (when cervical mucus dilutes the agglutinins) results.

It takes 60 days following infection for the mucus to become positive on test. In individual animals the stage of estrus cycle and the time of exposure to the disease must be known to identify the infection. Around ten (selected) to twenty animals are enough to diagnose at farm level.

Fluorescent antibody test used to detect antibody.

Sample collection

• Cervical mucus
• Reproductive discharges
• Aborted materials
• Blood and serum

Differential Diagnosis

• Infectious bovine rhinotracheitis
• Brucellosis
• Trichomoniasis
• Leptospirosis
• Listeriosis

Treatment

Macrolide antibiotics (erythromycin, clarithromycin, or azithromycin) are the most effective drugs for Campylobacter jejuni.

Fluoroquinolone antibiotics (ciprofloxacin, levofloxacin, gatifloxacin, or moxifloxacin) can also be used, but the organism is resistant to drugs.

Prevention

In systemically immunized cattle IgG found in the uterus and cervico-vaginal area is adequate enough to protect at the time of exposure.

When the serum antibody titer decrease the immunity also may be expected to decrease, so that reinfection occurs after vaccination and produce systemic anamnestic response. However, once the disease is established in the farm/herd animal will be immune to the infection and they resume the normal status.

The use of artificial insemination is successful in dairy herds. Vaccination is important for prevention of the disease. Vaccination of breeding herd twice prior to the breeding season to increases the high serum IgG titre is imperative. Single vaccination at 2 months prior to breeding is a failure to mount good immune status. Because serum antibody titre decreased rapidly after vaccination and therefore annual booster vaccine is recommended. Both males and females requires vaccination.

Control

Biosecurity: Proper disinfection of AI equipment with 1% sodium hypochlorite, 70% ethanol, 2% glutaraldehyde, Iodine based disinfectants, phenolic disinfectants, or formaldehyde is effective. Treatment with moist heat at 121 degree C for at atleast 15 min or dry heat at 160-170 degree celcius for at least 1 hour will inactivate C. fetus subspecies venerealis, which is also sensitive to gamma irradiation and UV radiation.

International Trade and BVC: In most countries, the import and export of cattle infected with C.fetus subsp. venerealis is prohibited. The guidelines on semen export requires that the bulls involved are C.fetus subsp. venerelais negative. In the European Union all bulls used for AI should be tested and free from campylobacteriosis in order to be licensed.

• Hand washing/sanitising on entry to broiler shed.
• Personnel hygeine.
• Access should be prevented between pets, livestock to the area surrounding the broiler sheds.
• Hygiene barriers to be constructed in all sheds.
• Avoid overcrowding in the sheds.
• Sanitation of water supply.
• Monospecific farms.
• Improved cleaning and disinfection of sheds or extended breaks between flocks.
• Control of beetles