Human and animal brucellosis in Jordan between 1996 and 1998: a study.

Between 1996 and 1998, a total of 2,494 samples of blood from humans and animals were collected and tested for brucellosis. This total included 1,594 samples of animal blood, collected from 1,050 sheep from 20 flocks, and 544 goats from eight herds. The serum samples were tested using the Rose Bengal test, the tube agglutination test, the complement fixation test and an enzyme-linked immunosorbent assay. Moreover, a complete history was compiled from each flock/herd. The rate of abortions in sheep due to brucellosis ranged from 0.5% to 56%, with a mean of 33.2%. The goats had a higher abortion rate. Thirty-four aborted sheep foetuses collected from these 20 flocks were bacteriologically and pathologically examined. A pure culture of Brucella melitensis biotype 3 was isolated from 21 of the aborted foetuses. The human blood samples were collected from two groups: first, from 800 apparently healthy people who were reporting to community hospitals for routine health checks and secondly, from 100 people from groups with a high-risk of contracting brucellosis, such as veterinarians, sheep-herders and laboratory technicians. The Brucella antibody titres for the 900 human serum samples were obtained using the microtitre agglutination test. The cumulative percentage of the serum samples showing a titre reading greater than 1:80 was higher in the at-risk group than among the normal population (7% compared to 4.1%). Although these results were not statistically significant, the higher percentage of positive reactors among the high-risk group may indicate an increased risk factor among professional agricultural and veterinary personnel in Jordan. It was concluded that brucellosis is common in sheep and goats in Jordan, subjecting the human population to high risks. Brucella melitensis Rev. 1 vaccination has been internationally recognised as the key to successfully controlling the disease. All animals in Jordan were repeatedly vaccinated between 1996 and 1998 on a trial basis, using a reduced dose of 1 x 10(5) colony-forming units (CFU). Cumulative data on the annual rate of human cases of brucellosis indicate that fewer people are affected each year. The same is true for the rate of abortions in animals. Such evidence strongly suggests that the vaccination programme has been successful. However, as wild strains of Brucella have also been isolated from vaccinated animals, the authors recommend increasing the amount of vaccine to a full dose of 1 to 2 x 10(9) CFU and vaccinating young female animals between the ages of three and eight months. To avoid brucellosis in humans, people should be educated about the dangers of contact with infected animals and the consumption of raw milk and milk products.

Equine babesiosis associated with strenuous exercise: clinical and pathological studies in Jordan.

Clinical, haematological and pathological studies were undertaken in Jordan in a stud of 103 racing horses clinically suffering from babesiosis and apparently healthy animals. Out of 47 horses which participated in strenuous exercise, three mares showed sudden onset of immobility and reluctance to move and two mares died. Clinical examination revealed that these five horses (group 1) had fever, anorexia, weakness and severe icterus and, in two mares, haemoglobinuria. Haematological examination revealed that all five horses were heavily parasitized with Babesia equi. This was also found in four horses (group 2) with no evidence of clinical babesiosis. In group 3 (94 horses), neither clinical signs nor B. equi were observed in the blood. The horses in group 1 and 2 recovered after treatment with imidocarb. When the mean values of white blood cell count, red blood cell count, haemoglobin and packed cell volume in group 1 were compared with those for groups 2 and 3, a significant difference was found (P < 0.05). A significant difference was also found when the mean values were compared before and after treatment. Examination of serum total protein, bilirubin and serum enzymes revealed a significant decrease in the mean value of total serum protein (P < 0.05), and a significant increase in the mean values of bilirubin (P < 0.05) in group 1 compared to groups 2 and 3. A significant elevation in the mean value of aspartate aminotransaminase, gamma-glutamyltransferase and creatine phosphokinase and a substantial elevation in the mean value of alkaline phosphatase was also observed in group 1 compared to groups 2 and 3. Postmortem examination of the dead horses showed that the animals had icterus, hepatomegaly and full urinary bladder with deep-red urine. Histopathological examination of the liver showed massive centrilobular degeneration and necrosis. The bile canaliculi and bile ducts were prominent and plugged with dark-brown to canary-coloured bile pigments. The lungs had congestion, oedema, and thrombosis of pulmonary veins. Our results suggest that the horses suffered from B. equal with clinical manifestation following exercise. The clinical, haematological and pathological findings indicate that the animals suffered from haemolytic anaemia which responded to imidocarb therapy.

Experimental infection of lambs with bovine respiratory syncytial virus and Pasteurella haemolytica: pathologic studies.

Nineteen 4-week-old, colostrum-deprived lambs were transtracheally inoculated with respiratory syncytial virus (RSV), Pasteurella haemolytica biotype A serotype 1, or RSV and P haemolytica. Pneumonic lesions were more frequent, more extensive, and more severe in lambs inoculated with RSV and P haemolytica than in lambs inoculated with either agent alone. Lesions were seen in 2 of 4 lambs inoculated with P haemolytica alone, in 3 of 4 lambs inoculated with RSV alone, and in 11 of 11 lambs inoculated with RSV and P haemolytica. Grossly, lambs given P haemolytica alone had fibrinous pleuritis and pneumonic lesions with hemorrhagic and necrotic centers which involved approximately 14% of the lung surface. Lambs inoculated with RSV alone had multifocal areas of consolidation and hemorrhage that involved 5% of the lung surface. Lambs in 2 groups inoculated with RSV and P haemolytica had lesions characteristic of both agents over 15% to 21% of the lung surface. Histologically, P haemolytica alone caused acute fibrinous pneumonia with necrosis of the lung parenchyma and fibrinous pleuritis; RSV alone caused interstitial pneumonitis, bronchiolitis, and hemorrhage. In combination, the agents caused interstitial pneumonitis and severe exudative pneumonia with focal necrosis and hemorrhage. Lesions seen in lambs given RSV and P haemolytica or in lambs given P haemolytica alone were grossly and histologically similar to those seen in naturally occurring cases of acute pneumonic pasteurellosis. Seemingly, the virus caused a lesion that compromised the lungs and thus permitted P haemolytica to become established and to produce a more severe pneumonic lesion than it could produce alone.

Experimental infection of lambs with bovine respiratory syncytial virus and Pasteurella haemolytica: clinical and microbiologic studies.

Four-week-old lambs were inoculated transtracheally with respiratory syncytial virus (RSV), Pasteurella haemolytica, or RSV and P haemolytica. When given in combination, RSV administration preceded P haemolytica by 3 or 5 days. Lambs inoculated with P haemolytica or RSV developed a mild respiratory tract disease accompanied by a transient pyrexia in a few lambs. By 24 hours after inoculation of bacteria, all lambs inoculated with RSV and P haemolytica were listless, reluctant to move, and exhibited hyperpnea and dyspnea. Most lambs had pyrexia and a few coughed and had serous nasal discharge. These clinical signs persisted for 3 to 4 days and were more pronounced in those inoculated with P haemolytica 5 days after RSV than in those inoculated with P haemolytica 3 days after RSV. Respiratory syncytial virus was isolated from 8 of 15 inoculated lambs and P haemolytica was isolated from 12 of 15 inoculated lambs. All lambs responded serologically to RSV, but none responded to P haemolytica.

Experimental infection of lambs with bovine respiratory syncytial virus and Pasteurella haemolytica: immunofluorescent and electron microscopic studies.

Colostrum-deprived lambs were inoculated transtracheally with respiratory syncytial virus (RSV), Pasteurella haemolytica, or RSV and P haemolytica. Multiple tissues were examined by immunofluorescence to localize viral and bacterial antigens, and lungs were examined by electron microscopy for cytopathologic changes. Using immunofluorescence, viral antigen was detected only in the respiratory tract, mainly in the bronchial and bronchiolar epithelium and in the alveolar wall. Lesser amounts of viral antigen were detected in the surface epithelium of the nasal turbinates and trachea. Bacterial antigen was not detected. Ultrastructurally, the lambs inoculated with P haemolytica or with RSV and P haemolytica had increased numbers of type II pneumocytes, necrotic epithelial cells, neutrophils, and macrophages and excessive cellular debris in multiple foci in the lungs. Bacterial were seen only infrequently; they were within phagocytic vacuoles of neutrophils and macrophages and were free within pulmonary septa. In lambs inoculated with RSV or with RSV and P haemolytica, cells in the epithelium were multinucleated. Viral buds were seen on cytoplasmic membranes of ciliated and nonciliated cells of bronchial and bronchiolar epithelium. Isolated epithelial cells were necrotic. Viral nucleoprotein was prevalent in a few alveoli, free or within vacuoles of phagocytic cells. Necrotic debris and phagocytic cells were more prominent in the alveoli of lambs inoculated with RSV and P haemolytica than in those of lambs inoculated with either agent alone.