Presentation on theme: "BRUCELLOSIS-2 Lecture on Epidemiology – 07-03-2012 L. Makrai SZIU-FVS, Department of Microbiology and Infectious Diseases."— Presentation transcript:
BRUCELLOSIS-2 Lecture on Epidemiology – 07-03-2012 L. Makrai SZIU-FVS, Department of Microbiology and Infectious Diseases
OVINE EPIDIDYMITIS AND ORCHITIS CAUSED BY Brucella ovis Occurs in most sheep-raising regions of the world (Australia, New Zealand, North and South America, South Africa, many countries in Europe) Infertility, epididymitis, orchitis in rams Sporadic abortion in ewes (placentitis) Increased perinatal mortality B. ovis, only sheep is susceptible
Epidemiology Introduction into a herd: with matured, infected, asymptomatic rams B. ovis is shed with urine and semen Lifelong infection Ewe: infected with semen (venereal transmission) several month – get shot of brucella ascending infection: epididymis, testicle, accessory genital glands: inflammation, necrosis, oedema, fibrosis, spermatokele
Clinical and Pathological findings incubation period: 5-9 weeks skin of scrotum is flushed painfull and enlarged epididymis and testicles abnormal gait unilateral or bilateral testicular atrophy with swelling and hardening of the epididymis decreasing quality of semen and sexual activity, reduced fertility in rams Chronic lesions: abscesses and necrotic foci in the testicles, uneven surface, calcification sporadic abortion in ewes increased perinatal mortality
Diagnosis Epidemiological situation, clinical signs Palpation of testicles microscopic and bacteriological examination of semen serology:- AGID - CFT - ELISA PCR (urine, semen, preputial washes) Differential diagnosis:- Histophilus somni - Actinobacillus seminis - B. melitensis Treatment: Pointless!
Prevention, Eradication Castration of infected rams! young, immature rams: separated rearing ELISA test 4-6 weeks intervals: removing seropositive rams
SWINE BRUCELLOSIS Occurence –Worldwide in swine-raising regions –It has been eradicated from domesticated pigs in the US, Canada, European countries and Australia, but it persits in wild and feral swine population. Biotype 1-3: worldwide 2: wild boars in Europe 4: arctic regions of North America, and Russia 5: in the former USSR (murine brucellosis)
Etiology: –B. suis bt. 1-2-3. Epidemiology: Introduction into a herd: - with infected, asymptomatic breeding animals - vehicles, instruments - dog, wild boar Pathogenesis: like cattle, Infection is aquired by ingestion or by coitus but: orchitis, vertebral osteomyelitis can be seen more frequently
Clinical signs: –bacteraemia: gen. asymptomatic –sows:abortion (any gestation period), stillbirth, neonatal mortality increase, non-viable or poorly developed piglets, vaginal discharge for several days temporary sterility –boars: excreting brucellae in semen (with or without clin. signs) Testicular abnormalities: orchitis, sterility Lameness, incoordination, posterior paralysis: vertebral abscess, fractures
Pathology: –Fetus: odema of fetus and fetal membranes, small haemorrhages, maceration, mumifiction –Sows: necrotic foci in uterine wall –Boars: enlarged testicle, inflammatory necrotic foci –Lesions in bones and joints: vertebral body - deformities
Diagnosis: –Isolation of B. suis –serology: Slide agglutination, tube agglutination, CFT, ELISA: susceptibility and specificity also low: only for livestock diagnosis!!! Treatment: NO! Eradication: Stock exchange!
Maintain the disease-free status: –Control of the import of susceptible animals –Examination of abortion cases in diagnostic institutes –Serological survey of breeding boars in each 6 month –Serological examination of 10% of sows in each year –Keeping wild boars away from swineherds
CANINE BRUCELLOSIS Occurence –Worldwide (America, Asia, Africa) –Europe: sporadic, everywhere –Free: New Zealand, Australia Susceptibility –B. canis –B. melitensis –B. abortus –B. suis
Epidemiology Host spectrum –narrow, dogs and the members of wild Canidae –zoonosis (more, than 40 cases in the literature) Infection oronasal contact, through mucous membranes (oral cavity, vagina, conjunctiva) infective dosis: –p.o.: 10 6 CFU –conjunctiva: 10 4 - 10 5 CFU Shedding bacteria: bitches:vaginal discharge (during oestrus, and mating), fetus, fetal fluid (10 10 CFU/ml) 6 weeks after abortion males:settle down in the postate and epididymis semen, urine: 10 3 - 10 6 CFU/ml for 2 years
Clinical signs No characteristic clinical signs, asymptomatic Enlargement of lymph nodes Pregnant bitches: –abortion (between 45-60. days), –reproduction failures (decreased fertility) –Reduced litter size –Neonatal mortality –Most bitches that have aborted subsequently have normal gestations. Males: infertility, epididymitis, orchitis, prostatitis Scrotal dermatitis (saliva!) Dogs with chronic infections are often aspermic. rare: discospondylitis (lameness, paresis, paralysis), uveitis
Leland E. Carmichael és Craig E. Greene, 1998 B. canis
Diagnosis Examination of semen –p.i. 5. weeks, inflammatory cells, morphological alteration of sperm Isolation of B. canis –from blood: pi 2-4 weeks – for years (5.5 years) Serological examination –Slide aggl., Tube Aggl., AGID, IF, ELISA –Earliest positive result: pi. 3-12 weeks
Fate of infected animal Removal of infected animals from the kennel and from breeding prgrammes. Castration (neutering) of infected dog and treatment with antibiotics reduces the risk of transmission.
Treatment Combination of –tetracyclines (minocycline) and –aminoglycosides (streptomicin) For 4 weeks or Extermination of infected animals!
Prevention serological examination: –Breeding dogs: in each 6 month –Introduction of a new dog into the kennel: two times in 1 month intervals –Breeding animals 3-4 weeks before mating. –If a dog leave the kennel: before readmission. Do not get dogs from a kennel, where reproductive problems occurs No vaccines available!
Brucellosis of other species Horse (B. abortus) – arthritis, bursitis and tendovaginitis, fistolous withers, poll-evil Wild ruminants (B. abortus) Wild boars (B. suis) – source of B. s. infection in domestic pigs reared outdoors Wild hare (B. suis bt. 2.)
HUMAN BRUCELLOSIS One of the most fequently seen bacterial zoonosis in the Earth. 500.000 new patient/year! Human is susceptible:MID50 B. melitensis++++ (10 1 ) B. abortus +++ (10 3 ) B. suis ++ (10 5 ) B. canis+ (10 6 ) B. ceti + B. pinnipedialis + Infection: - ingestion (po): raw -unpasteurized- milk! and dairy products made from this, - skin abrasions: during abortion, amniotic fluid, urine - inhalation (lab infections)
Clinical signs and pathological findings - incubation period: 5-14 days (3 months) - undulant fever (fluctuating pyrexia), malaise, inappetence, fatigue, muscle and joint pains - drenching sweats (at night) - bone and joints alterations (sacroiliitis, spondylitis, arthritis, osteomyelitis) - swelling of liver and spleen (33%) - lymph node alterations (10%) - alteration in urinary and genital tract (glomerulonephritis, kidney abscess, orchitis, epididymitis) (10%) - CNS signs (7%) - endocarditis (B. canis: can be asymptomatic, just seroconversion)
Treatment of human brucellosis: Should be administered early in an infection! –rifampicin –gentamycin –trimethoprim-sulfamethoxazole –doxycycline, minocycline –ciprofloxacin –streptomycin Long-term treatment may be required!
Diagnosis Anamnesis! Haemoculture serology (B. canis Ag!!!), no crossreaction with B. abortus Ag!!! –Slide agglutination –Tube agglutination –ELISA Fals diagnosis: –Lack of appropriate serological kit (S-R) –Occurence of the disease is underestimated Time after the first clinical signs Slide agglutination titer 2 months32 3 months16 8 months2
Prevention Veterinarians: examination of abortion cases - use of gloves and other protective clothing Education of owners about the danger of rearing of brucella infected animals Consumption of Raw milk should be avoided! Laboratory: safety rules must comply! The rules of common sense must be observed if we live together with animals!