Evaluation of spray and oral delivery of Newcastle disease I2 vaccine in chicken reared by smallholder farmers in central Ethiopia.

BACKGROUND: Newcastle disease (ND) is a highly infectious disease causing considerable economic losses to poultry farmers worldwide. Conventional vaccine delivery methods are not suitable for smallholder and rural poultry producers, and thus appropriate vaccination methods need to be sought. This study was carried out with the main objective of evaluating the efficacy of ND I2 vaccine delivered via drinking water and spray under smallholder farmers' condition in Minjar-Shenkora district, central Ethiopia. Twenty households were randomly assigned to intervention and control groups. Chickens owned by the selected households were randomly assigned to one of the three intervention groups. Blood samples were collected regularly for antibody assay from individual chicken vaccinated with ND I2 vaccine using different routes. RESULTS: At baseline, there was no difference in antibody titer among the experimental groups. After the first and booster vaccinations, the three vaccinated groups had significantly higher antibody titer (P < 0.001) than the unvaccinated control group. Interestingly, there was no statistically significant difference in antibody titer among the vaccinated groups. Out of the 40 chicken in the unvaccinated control only 14 had antibody titter≥ log23. Similarly 19/37 of chicken in the drinking water group, 19/37 of chicken in the eye drop group and 20/40 chicken in the spray group had antibody titer ≥ log23. Two weeks after the first vaccination the proportion of chicken with antibody titer ≥ log23 rose to 23/37, 30/37 and 29/40 in the group vaccinated via drinking water, eye drop and spray, respectively. The proportion remained low in unvaccinated group. Hundred percent of the vaccinated chicken survived after infection with the virulent ND virus (Alemaya strain); whereas only 40% survived from the unvaccinated control group. CONCLUSION: The results of this study showed that ND I2 vaccine administered via drinking water and spray under smallholder farmers' situation provoked protective antibody level similar to the eye drop method. The use of ND I2 vaccine could contribute to food security if used by rural poultry farmers properly.

Seroprevalence and risk factors for peste des petits ruminants in sheep and goats in Djibouti.

Despite the occurrence of peste des petits ruminants (PPR) in all other countries in the Horn of Africa, which engage in free animal movement, to date, PPR has not been reported in Djibouti. The objective of this study was to estimate the seroprevalence of PPR and its associated risk factors in sheep and goats in that country. A cross-sectional method was used with proportional sampling to allocate the number of small ruminants to be sampled from each of the country's regions (Ali Sabieh, Arta, Dikhil, Djibouti, Obock and Tadjourah). From a total of 1,516 serum samples tested, using a competitive enzyme-linked immunosorbent assay (cELISA), 91 were positive, with an overall 6% (95% confidence interval [CI] = 4.8-7.2) prevalence of antibodies to the PPR virus (PPRV). Antibodies to PPRV were detected in small ruminants from all the regions, excluding Obock. Seroprevalence was highest in the Tadjourah region (8.92%), whereas the lowest prevalence was observed in the Djibouti region (1.28%). The species, age and sex of the animals and the herd size were identified as risk factors for PPR seropositivity. The risk of goats testing positive for PPRV antibodies was2.95 (CI = 1.39-6.35) times that of sheep. Moreover, the risk of animals younger than two years testing positive for PPRV antibodies was 2.29 (CI = 1.47-3.56) times that of animals older than two years. Similarly, it was shown that female animals were more frequently infected (odds ratio [OR] = 3.82; CI = 1.51 to 9.67) than their male counterparts. In addition, small ruminants from small herds/flocks were more likely to be seropositive (OR = 2.06; CI = 1.10-3.83) than those from medium-sized herds/flocks. The present study revealed, for the first time, the widespread occurrence of PPRV antibodies in small ruminants in Djibouti with low prevalence.

Bien que présente dans tous les autres pays de la corne d'Afrique où la libre circulation des animaux est de mise, la peste des petits ruminants (PPR) n'a jamais été notifiée à Djibouti. Les auteurs présentent les résultats d'une étude visant à estimer la prévalence sérologique de la PPR ainsi que les facteurs de risque qui lui sont associés chez les ovins et les caprins du pays. Il a été fait appel à une méthodologie transversale afin de prélever un échantillon proportionnel représentatif des effectifs de petits ruminants de chaque région du pays (Ali Sabieh,Arta, Dikhil, Djibouti, Obock et Tadjourah). Au total, 91 des 1 516 prélèvements de sérum testés au moyen d'une épreuve immuno-enzymatique de compétition (ELISAc) ont donné des résultats positifs, soit une prévalence globale d'animaux possédant des anticorps dirigés contre le virus de la peste des petits ruminants(VPPR) de 6 % (intervalle de confiance [IC] à 95% de 4,8 à 16,2). La présence d'anticorps vis-à-vis du VPPR chez des petits ruminants a été détectée dans toutes les régions à l'exclusion d'Obock. La prévalence sérologique la plus élevée a été observée à Tadjourah (8,92 %) tandis que la plus faible concernait la région de Djibouti (1,28 %). Les facteurs de risque associés à la présence d'anticorps contre la PPR étaient l'espèce, l'âge et le sexe des animaux, ainsi que la taille du troupeau. La probabilité de détection d'anticorps vis-à-vis du PPRV était 2,95 fois plus élevée chez les chèvres que chez les moutons (IC de 1,39 à 6,35). De plus, la probabilité de trouver des anticorps contre le VPPR était 2,29 fois plus élevée chez les jeunes de moins de deux ans que chez les animaux âgés de plus de deux ans (IC de 1,47 à 3,56). De même, l'infection était plus fréquente chez les femelles que chez les mâles (rapport de cotes ou odds ratio [OR] de 3,82 ;IC compris entre 1,51 et 9,67). Enfin, la probabilité d'être porteur d'anticorps était plus élevée chez les petits ruminants élevés dans des troupeaux ou cheptels de petite taille (OR de 2,06 ; IC de 1,10 à 3,83) que chez ceux appartenant à des troupeaux ou cheptels de taille moyenne. Cette étude fait état pour la première fois de la présence sur une vaste partie du territoire de Djibouti de petits ruminants porteurs d'anticorps dirigés contre le VPPR, à une prévalence relativement faible.

Aunque la peste de pequeños rumiantes (PPR) está presente en todos los demás países del Cuerno de África que participan de la libre circulación de animales, a día de hoy no se ha notificado su presencia en Djibouti. Los autores describen un estudio destinado a estimar la seroprevalencia de la enfermedad y sus factores de riesgo en los ovinos y caprinos de este último país. Para ello se utilizó un método transversal, asignando a cada una de las regiones del país (Ali Sabieh, Arta, Dikhil, Djibouti, Obock y Tadjoura) un número proporcional de muestras que extraer de la población de pequeños rumiantes. De un total de 1516 muestras de suero analizadas con un ensayo inmunoenzimático de competición (ELISAc), 91 resultaron positivas, lo que supone una prevalencia global de anticuerpos contra el virus de la PPR del 6% (intervalo de confianza [IC] al 95% = 4,8­7,2). Se detectaron anticuerpos en pequeños rumiantes de todas las regiones con la salvedad de Obock. El máximo nivel de seroprevalencia se registró en la región de Tadjoura (un 8,92%), mientras que el nivel más bajo se observó en la de Djibouti (un 1,28%). Como factores de riesgo de seropositividad se encontraron la especie, la edad y el sexo del animal, así como el tamaño del rebaño. El riesgo de seropositividad, o presencia de anticuerpos contra el virus de la PPR, era 2,95 veces mayor en los caprinos (IC = 1,39­6,35) que en los ovinos. Por otra parte, el riesgo de que los ejemplares de menos de 2 años resultaran positivos era 2,29 veces superior (IC = 1,47­3,56) al de los animales de más edad. Análogamente, quedó demostrado que las hembras resultaban infectadas con más frecuencia (razón de posibilidades [odds ratio: OR] = 3,82; IC = 1,51 a 9,67) que los machos homólogos. Además, los pequeños rumiantes de rebaños de escaso tamaño tenían mayor probabilidad de resultar seropositivos (OR = 2,06; IC = 1,10­3,83) que los de rebaños de mediano tamaño. El estudio puso de manifiesto, por primera vez, la presencia extendida, pero con escasa prevalencia, de anticuerpos contra el virus de la PPR en los pequeños rumiantes de Djibouti.

Improved molecular detection of Ehrlichia and Anaplasma species applied to Amblyomma ticks collected from cattle and sheep in Ethiopia.

Detection of Ehrlichia and Anaplasma species in animals and tick vectors is crucial for an understanding of the epidemiology of diseases caused by these pathogens. In this study, a pair of primers designated EBR2 and EBR3 was designed from the Anaplasma 16S rDNA sequence and was used along with a previously described primer EHR 16SD for the simultaneous detection of Ehrlichia and Anaplasma species by nested PCR. The primers were used to amplify 925bp of DNA from known species of Ehrlichia and Anaplasma. Restriction with MboII and MspI enzymes allowed Ehrlichia and Anaplasma speciation. Restriction with MboII differentiated between An. marginale, Anaplasma (formerly Ehrlichia) sp. Omatjenne, and An. centrale with An. marginale and Anaplasma (formerly Ehrlichia) sp. Omatjenne yielding 2 distinct fragments each while An. centrale produced 3 distinct bands. Ehrlichia ruminantium and An. phagocytophylum remained undigested. Subsequent restriction with MspI differentiated E. ruminantium from An. phagocytophylum with 2 and 4 fragments, respectively. When used on tick samples from the field, 63 ticks (16.4%) out of 384 collected from cattle and sheep were positive for one or more species of Ehrlichia and Anaplasma. The positivity ranged from 6.3% at Andasa to 36.7% at Habernosa. Higher overall infection rates were found in Amblyomma lepidum than in Amblyomma variegatum ticks (p=0.009). Amblyomma lepidum from Habernosa were more often infected with all detected species of Anaplasma and Ehrlichia than Am. variegatum. At Bako, however, Anaplasma (formerly Ehrlichia) sp. Omatjenne was detected only in Am. variegatum. A significantly higher proportion of ticks collected from cattle (20.6%) was found positive than in those collected from sheep (3.3%) (p=0.003). Simultaneous detection of Ehrlichia and Anaplasma species and correct identification of mixed infections was possible. Since the ticks were collected from animals, the occurrence of the major species of Ehrlichia and Anaplasma in ruminants in the area is confirmed.

Epidemiological study of bovine brucellosis in three agro-ecological areas of central Oromiya, Ethiopia.

A cross-sectional sero-epidemiological study of bovine brucellosis was conducted between September 2005 and March 2006 in three separate agroecological areas of central Oromiya, Ethiopia. In this study, a total of 176 clusters (farms) and 1,238 animals were selected, using the one-stage cluster sampling method. Fifty-nine clusters and 423 animals were selected from the lowland areas; 58 clusters and 385 animals from the midland areas and 59 clusters and 430 animals from the highlands. Serum samples were collected from a total of 1,238 animals older than six months. The rose bengal plate test and complement fixation test were used as screening and confirmatory tests, respectively, to detect Brucella seropositivity. Questionnaires were also administered to 176 households to gather information on the farm and livestock. Results showed that the overall seroprevalence of bovine brucellosis at the individual animal level was 2.9% (low). The seroprevalence was 4.2% in the lowlands, 1.0% in the midlands and 3.4% in the highlands. The overall seroprevalence at the herd level was 13.6% (moderate). At the herd level, seroprevalence in the lowlands was 17%; in the midlands: 5.1%; and in highland areas: 18.6%. Logistic regression analysis, revealed that the breed of cattle and the method of disposing of aborted foetuses and foetal membranes had a statistically significant effect on individual animal seroprevalence (p < 0.05). In lowland areas, the breed (p < 0.05), animal management system (p <0.05), mating method (p < 0.05), herd size (p < 0.05) and source of replacement stock (p <0.05) all had significant effects on individual animal seroprevalence.

Serological survey of caprine toxoplasmosis in Ethiopia: prevalence and risk factors.

The study was conducted to determine the prevalence and risk factors of toxoplasmosis in goats in Southern and central Ethiopia between October 2005 and May 2006. A total of 641 goats sera were tested using Modified Direct Agglutination Test (MAT), of which 480 (74.8% CI: 71.3, 78.2) were found to be positive. The highest prevalence was recorded in South Omo zone (82%) while the lowest was observed in East Shewa zone (62.2%). The study revealed that goats raised in southern Ethiopia are at a greater risk of acquiring T. gondii infection (OR = 2.55, CI: 1.726, 3.776; p = 0.000) than those which are raised in central Ethiopia. The prevalence of anti T. gondii antibody was significantly higher in older goats than in kids (OR = 2.33, CI: 1.490, 3.655; p < 0.0002) and in females than in males (p < 0.0007; OR = 0.68, CI: 0.542, 0.849). No significant difference was observed among goats kept under various husbandry practices. The high prevalence of toxoplasmosis in Ethiopian goats suggests a high risk of human infections. Further epidemiological investigation, isolation and genotyping of T. gondii are planned.

Distribution of brucellosis among small ruminants in the pastoral region of Afar, eastern Ethiopia.

A cross-sectional study was conducted in the pastoral region of Afar, in eastern and central Ethiopia, to determine the distribution of brucellosis in small ruminants. Between December 2005 and June 2006, 1,568 serum samples were taken: 563 samples from sheep and 1,005 from goats. One hundred and forty-seven of these (9.4%) tested positive using the Rose Bengal plate test (RBPT), and 76 (4.8%) also tested positive by the complement fixation test (CFT). Brucellosis was detected in all five administrative zones of the region. The difference in prevalence (P) among the zones was not statistically significant (P > 0.05). The seroprevalence of Brucella infection was found to be 5.8% (n = 58) in goats and 3.2% (n = 18) in sheep. A prevalence rate of 5.3% was observed in adult animals and 1.6% in younger sheep and goats. Caprine species (chi2 = 5.56) and adult goats and sheep (chi2 = 4.84) were found to be at higher risk of Brucella infection (P < 0.05). No statistically significant difference was found between males and females (chi2 = 2.57, P > 0.05). The study showed that small-ruminant brucellosis is a widely distributed disease in Afar. The authors recommend the implementation of well-organised disease control and prevention methods to mitigate the economic losses and public health hazard caused by the disease.

[Status of diabetes in Ethiopia as a contribution to tropical diabetes mellitus]. / Zur Diabetessituation in der VDR Athiopien als Beitrag zum tropischen Diabetes mellitus.

On the basis of own experiences with the care of diabetes in the northern highland of Ethiopia the particularities of the tropical diabetes mellitus are described. In the light of the control score according to Noviks and co-workers the quality of the metabolic management of 100 patients is estimated as above all unsatisfactory, from which the conclusion is to be deduced more than up to now to include the diabetes mellitus into the health care system of Ethiopia and to improve thoroughly the conditions for the diagnostics, the therapy, education and dispensary care.