Prevalence and financial effects of hydatidosis in cattle slaughtered in Birre-Sheleko and Dangila Abattoirs, Northwestern Ethiopia

A cross-sectional survey of bovine hydatidosis was carried out on local zebu cattle slaughtered at Birre-Sheleko and Dangila Abattoirs from August 2007 to July 2008 to determine the prevalence and to estimate financial loss caused by the disease. Postmortem examination, hydatid cyst characterization and direct and indirect financial loss estimations were conducted. Out of the total of 521 animals examined (255 Birre-Sheleko and 266 Dangila), 79 (15.2%) were found harbouring one or more hydatid cyst. The prevalence of the disease between the two abattoirs was not significantly different (P > 0.05). The result obtained from postmortem examination indicated that a total of 112 visceral organs were found harbouring one or more hydatid cysts. The involvement of lung, liver, spleen and kidney was found to be 70.5%, 21.4%, 6.3% and 1.8% respectively. From the total of 224 cysts counted, 147 (65.6%), 29 (12.9%), 3 (1.3%) and 45 (20.1%) were small, medium, large and calcified cysts respectively, and 114 (50.9%) and 65 (29%) were sterile and fertile cysts respectively. Viability rate of 47.7%, all from the lungs, and higher liver calcification rate were observed. The annual financial loss from organ condemnation and carcass weight loss due to bovine hydatidosis at Birre-Sheleko and Dangila abattoirs were estimated to be $18911.6.

Retrospective survey of human hydatidosis in Bahir Dar, north-western Ethiopia

To determine the prevalence of human hydatidosis in Bahir Dar and the sex and age distribution and awareness, we used a questionnaire and retrospective analysis covering 5 years of the case reports at public health institutions in Bahir Dartown and the surrounding areas. We interviewed 244 individuals: 150 households, 32 abattoir workers, 30 butchers and 32 health professionals. None of the householders or butchers knew about cystic echinococcosis, nor did 25% of the health professionals; however, 100% of the abattoir workers and 75% of the health professionals recognized it. The householders owned on average 3 livestock and 1 dog and during holidays, ceremonies and other feasts, the community mostly practised backyard slaughter. Case book analysis between January 2002 and December 2006 showed that out of the total of 36,402 patients admitted for ultrasound examination, 24 hydatidosis cases were registered, giving a mean annual incidence rate of approximately 2.3 cases per 100,000 per year. Ultrasound was the most frequently used diagnostic method.

Seroprevalence of Toxoplasma gondii in Nazaret town, Ethiopia

OBJECTIVE

To determine the seroprevalence of toxoplasmosis, assess its zoonotic importance and identify factors associated with seroprevalence.

METHODS

Questionnaire survey was conducted on 65 serum samples collected from male and female urban and peri-urban residents aged between 15 days and 65 years. Main outcome measures were feeding habits, purpose of keeping cats and association with family members. Serologic evidence of toxoplasmosis was conducted by the Modified Direct Agglutination Test (MDA T) and determination of HIV status using the HIV - Spot Test.

RESULTS

Over 50% of the interviewed people had a history of consumption of raw or undercooked mutton and had close contact with cats. 60% of the serum samples analyzed by the MDA T had serologic evidence of Toxoplasma infection. Significantly higher MDA T tiers were encountered both in pregnant and immunocompromised individuals. The risk factors associated to Toxoplasma infection, i.e. raw or undercooked mutton consumption and presence of cats appeared significant.

CONCLUSION AND RECOMMENDATIONS

The significance of toxoplasmosis as a disease of zoonotic importance was demonstrated. Close contact between family members and the consumption of raw or undercooked mutton were the major risk factors in the transmission of the disease. Considering the relatively high prevalence as revealed by this study it would be important to conduct studies on a wider scale. It would also be important to increase public awareness and upgrade the knowledge on congenital toxoplasmosis.

Bovine cysticercosis in cattle slaughtered at Awassa municipal abattoir, Ethiopia: prevalence, cyst viability, distribution and its public health implication

A cross-sectional study was conducted from October 2005 to April 2006 on bovine cysticercosis in cattle slaughtered at Awassa municipal abattoir with the objective of determining the prevalence of Taenia saginata cysticercosis, cyst viability, distribution and its public health implication. Questionnaire survey involving 120 respondents was also conducted on human taeniasis. A total of 400 carcasses were examined during the study period, of which 105 (26.25%) were infected with T. saginata metacestodes. From a total of 3200 samples inspected, 500 cysticerci were detected in 141 samples, of which 221 (44.2%) were alive. The anatomical distribution of cysticerci were 65 (29.2%) heart, 56 (25.3%) shoulder muscle, 59 (26.7%) masseter, 23 (10.4%) tongue, 12 (5.4%) diaphragm, three (1.4%) liver, two (0.9%) lung and one (0.5%) kidney samples. The prevalence varied significantly between local and crossbred animals (OR = 3.15, P < 0.05), but not varied between sex, age groups and origin of the animals. T. saginata taeniasis was a widespread public health problem in the town with an overall prevalence of 64.2% (77 of 120). The potential risk factors for disease contraction were raw meat consumption, religion and occupational risks. In conclusion, the study revealed high prevalence of T. saginata metacestodes throughout the edible organs together with existence of deep-rooted tradition of raw meat consumption. This may magnify the public health hazards of T. saginata in the study area. As a result, the disease deserves due attention to safeguard the public health and further promote beef industry in the country.

Taeniasis and its socio-economic implication in Awassa town and its surroundings, Southern Ethiopia

OBJECTIVE

The study was conducted between October 2005 and April 2006 in Awassa town and its surroundings to investigate the status of T. saginata taeniasis, its socio-economic importance and potential risk factors.

METHODS

Questionnaire survey was conducted on 120 volunteer individuals selected at random. Additionally, retrospective study on taenicidal drugs inventories at 12 pharmaceutical shops was conducted.

RESULTS

T. saginata taeniasis was a wide spread problem in the town and its surroundings with overall prevalence of 64.2% (77 out of 120) and maximum infection frequencies of five times per year. The prevalence of taeniasis was significantly varied between religion, occupation, raw meat consumption and use of spices with raw meat. Accordingly, Christian communities (OR = 5.2, 95% CI = 1.20-22.50), high-risk groups (OR = 4.05, 95% CI = 1.27-12.93), raw meat consumers (OR = 7.9, 95% CI = 2.46-5.66), and spices users (OR = 11.6, 95% CI = 2.85-47.28) had higher likelihood of acquiring taeniasis than Muslim communities, low risk groups, cooked meat eaters and non-spices users, respectively. Conversely, prevalence was not varied between sex, age, marital status and educational backgrounds of the respondents. Respondents' preferences to available taenicidal drugs had strong linear relationship with drug dose sold (R2 = 0.92), and showed that Niclosamide (46.8%) was the drug of first choice while Praziquantel (13%) was the least preferred drug. The taenicidal drug doses and treatment cost from 2002 to 2005 were estimated to be 4,913,346 adult doses and 820,343 USD (7,219,021 Eth. Birr as per rate of 2006).

CONCLUSION

Taeniasis was a wide spread problem with higher prevalence and frequent infections in the town and its surroundings. Sociocultural conditions and occupation were the major risk factors for the occurrence of the disease. Hence, owing to its public health and economic importance, taeniasis deserves serious attention in order to safeguard the public health.

Seroprevalence of Toxoplasma gondii in Nazareth Town, Ethiopia

OBJECTIVE

To determine seroprevalence of toxoplasmosis, assess its zoonotic importance and identify factors associated with seroprevalence.

DESIGN

Questionnaire survey and serological studies.

SUBJECTS

Questionnaire survey and 65 serum samples from male and female urban and peri-urban residents aged between 15 days and 65 years.

MAIN OUTCOME MEASURES

Feeding habits, purpose of keeping cats and association with family members, serologic evidence of toxoplasmosis by the Modified Direct Agglutination Test (MDAT), examination of HIV status using the HIV-Spot Test.

RESULTS

Over 86% of the interviewed people had a history of consumption of raw or undercooked mutton and had close contact with cats. Of the serum samples analyzed by the MDAT 60% had serologic evidence of Toxoplasma infection. Significantly higher MDAT tiers were encountered both in pregnant and immunocompromised individuals. The risk factors associated with Toxoplasma infection, i.e. raw or undercooked mutton consumption and presence of cats appeared significant.

CONCLUSION AND RECOMMENDATIONS

The significance of toxoplasmosis as a disease of zoonotic importance was demonstrated. Close contact between family members and the consumption of raw or undercooked mutton were the major risk factors in the transmission of the disease. Considering the relatively high prevalence as revealed by this study it would be important to conduct studies on a wider scale. It would also be important to increase public awareness and upgrade the knowledge on congenital toxoplasmosis.

In vitro and in vivo anthelmintic activity of crude extracts of Coriandrum sativum against Haemonchus contortus

In vitro anthelmintic activities of crude aqueous and hydro-alcoholic extracts of the seeds of Coriandrum sativum (Apiaceae) were investigated on the egg and adult nematode parasite Haemonchus contortus. The aqueous extract of Coriandrum sativum was also investigated for in vivo anthelmintic activity in sheep infected with Haemonchus contortus. Both extract types of Coriandrum sativum inhibited hatching of eggs completely at a concentration less than 0.5 mg/ml. ED(50) of aqueous extract of Coriandrum sativum was 0.12 mg/ml while that of hydro-alcoholic extract was 0.18 mg/ml. There was no statistically significant difference between aqueous and hydro-alcoholic extracts (p>0.05). The hydro-alcoholic extract showed better in vitro activity against adult parasites than the aqueous one. For the in vivo study, 24 sheep artificially infected with Haemonchus contortus were randomly divided into four groups of six animals each. The first two groups were treated with crude aqueous extract of Coriandrum sativum at 0.45 and 0.9 g/kg dose levels, the third group with albendazole at 3.8 mg/kg and the last group was left untreated. Efficacy was tested by faecal egg count reduction (FECR) and total worm count reduction (TWCR). On day 2 post treatment, significant FECR was detected in groups treated with higher dose of Coriandrum sativum (p<0.05) and albendazole (p<0.001). On days 7 and 14 post treatment, significant FECR was not detected for both doses of Coriandrum sativum (p>0.05). Significant (p<0.05) TWCR was detected only for higher dose of Coriandrum sativum compared to the untreated group. Reduction in male worms was higher than female worms. Treatment with both doses of Coriandrum sativum did not help the animals improve or maintain their PCV while those treated with albendazole showed significant increase in PCV (p<0.05).

Multiple-drug resistant Trypanosoma congolense populations in village cattle of Metekel district, north-west Ethiopia

Investigations were carried out to determine the prophylactic activity of isometamidium chloride in village populations of cattle naturally infected with trypanosomes in Metekel district, northwest Ethiopia. In a cross-sectional study in March 1997, 484 randomly selected cattle from four villages were examined for trypanosome infections by the dark ground/phase contrast buffy coat technique (BCT). The trypanosome prevalence was 17.2%. Trypanosoma congolense was the dominant species accounting for 47.6% of the overall infections. Fifty parasitaemic cattle from two villages were treated with isometainidium chloride (Trypamidium(R)) at a prophylactic dose of 1.0 mg/kg body weight (b.w.) and thereafter monitored on a monthly basis for parasitaemia. Trypanosomes were detected in six cattle within 1 month and in 18 cattle within 2 months of treatment. Twenty three percent (6/26) of cattle infected with T. congolense at the time of treatment were detected parasitaemic with this trypanosome species 1 month after treatment. Mice were infected with three T. congolense isolates obtained from cattle which were detected parasitaemic within one or 2 months after isometamidium treatment. The mice were subsequently treated with ranges of doses of isometamidium chloride or diminazene aceturate (Berenil(R)) and thereafter monitored for parasitaemia for a period of 60 days. Isometamidium chloride at doses of 0.5-4.0 mg/kg b.w. and diminazene aceturate at doses of 3.5-28.0 mg/kg b.w. failed to cure T. congolense infections in any of the animals. Three clones were derived from one of the isolates; each clone expressed high levels of resistance to both trypanocides when tested in mice. Based on these results it is concluded that the prophylactic activity of isometamidium is greatly reduced for some of the T. congolense populations present in the area, and in addition there is resistance to diminazene aceturate in this trypanosome species.

Prevalence of bluetongue virus antibodies in sheep in central Ethiopia

Competitive ELISA was applied to detect antibodies against bluetongue virus in sheep sera collected from different agro-climatic areas in Ethiopia. A total of 90 serum samples were tested and 42 (46.67%) were positive for bluetongue virus antibodies. A prevalence rate ranging from 9.67% for sheep sampled in the highland to 92.85% for sheep sampled in the lowland was recorded. The prevalence correlated with the probable distribution of the Culicoides vector. This is the first report indicating the presence of bluetongue virus infection in animals from Ethiopia.

Financial losses caused by ovine fasciolosis in the Ethiopian highlands

An estimate of the economic loss due to ovine fasciolosis in the Ethiopian highlands was made based on available data on mortality, weight loss, reduced reproductive efficiency and liver condemnation at slaughter. The economic effects of fasciolosis were identified and models for estimating the financial loss presented. Ovine fasciolosis losses were estimated at 48.4 million Ethiopian Birr per year of which 46.5, 48.8 and 4.7% were due to mortality, productivity (weight loss and reproductive wastage) and liver condemnation, respectively. These losses can be reduced substantially by fasciolosis control programmes that may include the use of anthelmintics, grazing management and nutritional supplementation.

Sensitivity and specificity of the indirect fluorescent antibody test in the study of four murine coccidia

The sensitivity and specificity of the indirect fluorescent antibody (IFA) test for the detection of serum antibodies were examined in mice that were infected with Eimeria falciformis, E. ferrisi, E. papillata, or E. vermiformis. For the study of each species, five groups of mice were given graded inoculation doses of 10, 10(2), 10(3), 10(4), or 10(5) sporulated oocysts in a primary infection. The sixth group was infected with three sequential doses of 1.5 x 10(3), 1.5 x 10(4), and 1.5 x 10(5) sporulated oocysts per mouse at two- to three-week intervals. All groups of infected mice developed serum antibodies. Sera were titrated by the IFA test with purified sporozoites. Strong fluorescence and high IFA titers were observed with homologous reactions mainly with the sera from mice infected with the higher inoculation dose levels in primary infections and from those given three sequential inoculation doses. Immunological cross reaction among the four species of Eimeria occurred at dilutions of 1:10 to 1:160. Very weak or no fluorescence of free sporozoites was observed with sera from noninfected mice, and there was no fluorescence of sporozoites contained in intact sporocysts.

Oocyst production of four species of murine coccidia

Oocyst output and the reproductive potential of the four species of murine coccidia, Eimeria falciformis, E. ferrisi, E. papillata, and E. vermiformis were examined. Graded infections were produced by inoculating either 10, 102, 103, 104, or 105 sporulated oocysts to groups of mice. Oocyst production was estimated by examining all the feces passed. oocyst output was influenced by the size of the dose of oocysts. Maximum oocyst production per mouse was observed in groups of mice infected with 103 to 104 sporulated oocysts, after which, decline in oocyst output was observed despite increasing the dose of oocysts. The reproductive potential per oocyst given in each of the four species of Eimeria decreased as the dose of oocysts was increased. Mortality at rates of 60 and 40%, respectively, occurred in groups of mice infected with 105 sporulated oocysts of E. vermiformis and E. ferrisi.