Ectoparasitic fauna of poultry in Nsukka, Nigeria

An investigation which lasted for a period of one calendar year was mounted to determine common ectoparasitic fauna of poultry in Nsukka, Nigeria. This survey covered twenty commercial poultry farms located in different areas of Nsukka. Birds were picked and thoroughly examined visually for the presence of ectoparasites after horizontal displacement of the feathers against their anatomical direction of alignment. Identification was mainly by morphological characteristics, host preference and anatomical location. The result of the survey indicates that 15 (75%) out of a total of 20 farms sampled were infested. Furthermore, the orders Mallophaga and Anoplura were commonly recovered. Common ectoparasites identified and their prevalence rates are as follows: Gonoides gigas (15.0%), Menacanthus stramineus (20.0%), Lipeurus caponis (25.0%), Ceratophyllus gallinae (25.0%) and Amblyomma sp. (15.0%). The veterinary importance of these ectoparasites are highlighted and possible control measures against ectoparasitic build up in poultry houses recommended.     

Dumb (paralytic) rabies in dogs in Nigeria

Five cases of dumb rabies were examined, quarantined and observed from the time of presentation until death. Two of the dogs bit four people, three children and an adult. Ages of dogs ranged from eight weeks to 30 months. Only one of these dogs had been vaccinated against rabies. One dog out of the five was simultaneously affected with trypanosomiasis and inapparent rabies. The predominant diagnostic clinical signs were conjunctival congestion, glazed eyes and idiopathic ataxia. Postmortem examination was performed on two dogs. Rabies was confirmed by the finding of Negri bodies in brain smears and by the mouse inoculation test (MIT).     

Prevalence of ectoparasites of small ruminants in Nsukka, Nigeria

Over a period of one year (January 1983 to December 1983), an investigation was mounted to determine common ectoparasitic infestation of small ruminants in selected farms in Nsukka, Nigeria. The species identified in goats included Ctenocephalides canis, Boophilius decolouratus and Amblyomma variegatum lides while those recovered from parasitized sheep were Ctenocephalides canis and Damalinia ovis. Out of a total of 148 sheep and goats examined for ectoparasites, 68 (45.95%) were infested. A further breakdown of this figure shows that 10 (18.52%) out of a total number of 54 sheep screened were infested, while 58 (61.70%) of the goats (94) examined were infested. Identification of these ectoparasites was by anatomical and morphological characteristics. Result of the investigation indicated that there was variation in the degree of ectoparasitic infestation from one animal to another. Epizootiological factors associated with ectoparasitic infestation of small ruminants were highlighted and the zoonotic importance of Ctenocephalides canis and Amblyomma variagatum was discussed.     

Seasonal prevalence of protozoan parasites in Nsukka, Nigeria.

Five hundred fresh stool specimens of patients with clinical symptoms of protozoan infections were examined for parasites. During June 1988-May 1991, the total number of positive cases was 261 (52.2 per cent). When the infectivity frequencies were segregated among the samples of different localities, it was observed that 6 (1.2 per cent) persons from the University of Nigeria community, 89 (17.8 per cent) urban dwellers and 166 (33.2 per cent) rural populace were infected. The highest incidence of Giardia lamblia (83, 47.8 per cent), Entamoeba histolytica (49, 28.3 per cent) and Chilomastix mesnili (34, 19.7 per cent) was found among the rural community. The infection started in April of each year (onset of rainy season), peaked between July and August, and was the lowest between November and March (dry season). Statistical interpretation of the results indicated that the parasitic infections depended on times of the year x2 0.01 > 4 calculated x2 0.01, 0.05 > 4 tabulated. The vehicle of transmission of the infection was green vegetable (Amaranthus viridans) which gets polluted by sewage oxidation pond at the locality.     

Seroepidemiological survey of Leishmania infantum infection in dogs from northeastern Portugal

Northeastern Portugal is a region where canine leishmaniasis (CanL) is endemic. In this study, a sero-epidemiological survey was conducted in 654 dogs from that geographical area. Serum samples were evaluated by the direct agglutination test (DAT) and also by enzyme-linked immunosorbent assay (ELISA) using five different defined antigens. Seroprevalence of infection was 21.3% based on the assumption that seropositive animals were positive for at least three tests. A high degree of agreement was found between DAT and LAM-ELISA (89%; kappa value [κ] = 0.67). A statistically significant difference (p<0.05) of seropositivity was found between adult (23.4%) and juvenile dogs (12.2%), apparently healthy (14.8%) and sick dogs (40.2%), vaccinated (19.7%) and non-vaccinated (41.2%) animals, seropositive (26.9%) and seronegative (18.0%) for Toxoplasma gondii, living in rural (18.5%) or urban (32.6%) areas, and between animals living exclusively outdoors (18.2%) and those living in a mixed habitat (27.5%). Risk factors for canine Leishmania infection, as defined by multiple logistic regression analysis, were of clinical status (odds ratio [OR] = 3.1) and Toxoplasma infection (OR = 1.5).     

胶体金免疫层析检测犬、猫抗狂犬病病毒IgG抗体的研究

目的建立检测犬、猫抗狂犬病病毒(RV)IgG抗体的胶体金免疫层析方法。方法采用柠檬酸三钠还原法制备胶体金用以标记SPA,同时将重组RVN蛋白、抗SPA抗体分别包被至硝酸纤维素膜的检测线与质控线上,制备一种检测犬、猫抗RVIgG抗体的胶体金检测卡,进行了特异性和灵敏度试验,并与ELISA同时检测临床样品、统计结果。结果 GICA试纸条检测灵敏度为0.5IU/mL,与犬瘟热病毒、犬细小病毒等阳性血清无交叉反应,并与ELISA相比,两者的符合率为94.6%。结论成功建立了检测犬、猫抗RVIgG抗体的通用型胶体金免疫层析方法 ,该方法灵敏度高,特异性强,检测速度快,操作简便,可广泛应用于基层。     

上海地区2004年疑似狂犬的病毒检测分析及其应用

目的对2004年上海地区疑似狂犬进行病毒检测,分析应用于狂犬伤多人应急事件的处理。方法收集126份疑似狂犬病的犬脑标本,用ELISA法快速检测狂犬病毒抗原、小鼠感染法(MIT)分离病毒和免疫荧光法(IF)鉴定病毒型别。对疑似狂犬进行地区和时间分布调查。结果3种方法完全一致。确诊狂犬的阳性率为22.2%(28/126),鉴定为1型狂犬病毒。6-8月检出率最高,为全年的75%(21/28)。病毒检测阳性的地区进行紧急防治措施。结论狂犬病毒检测3种方法,既可快速诊断,又可获得定型的毒株。便于对狂犬地区采取应急防治措施,利于控制预防狂犬病。     

Prevalence of Toxocara canis ova on playgrounds of nursery schools in Nsukka, Nigeria

Soil samples taken from playgrounds in the eleven Nursery schools in Nsukka were examined for the prevalence of Toxocara canis ova. T. canis ova were identified from 6 out of the 11 schools samples, a prevalence of 54.5%. The public health risk of this finding to the children in these schools with regards to visceral larva migrans in highlighted and recommendations made for prevention and control.     

Seroepidemiological survey on dengue and Japanese encephalitis virus infections in Asian monkeys

To investigate the ecology of dengue and Japanese encephalitis (JE) viruses in the forest in Asia, a seroepidemiological survey was carried out on 358 Southeast Asian cynomolgus (Macaca iris), 33 Indian bonnet (Macaca radiata) and 37 Japanese (Macaca fuscata) monkey sera by a plaque reduction neutralization test. The results indicated that Southeast Asian monkeys were naturally infected with these viruses but the frequency of antibody to them varied considerably according to the geographical origin of the monkeys. The frequency of antibody to one or more types of dengue virus were 87.2, 49.5, 34.3, 34.2 and 14.9% in Malaysian, Vietnamese, Cambodian, Indonesian and Filipino cynomolgus monkey sera, respectively. None of the Indian bonnet monkey sera neutralized type 1 dengue virus which was the only virus type examined with this monkey species. Monkey sera collected in Japan where dengue virus infection had not been known since 1944 did not significantly neutralize dengue viruses. JE virus antibody was detected at 29.7, 9.0, 8.6, 2.7, 1.4 and 0% in Japanese, Cambodian, Vietnamese, Indonesian, Filipino and Malaysian monkey sera respectively.     

Calculating rabies virus neutralizing antibodies titres by flow cytometry

The determination of the rabies neutralizing antibody (VNA) response after immunization against rabies is an acceptable index of the efficacy of a vaccine and a successful treatment. Several tests have been developed in attempt to improve the assessment of VNA, from mice inoculation to cell-culture fluorescence inhibition tests. All of them, however, present special difficulties in terms of reading or accuracy. The present study describes a neutralization test performed in cell-culture appraised by flow cytometry (FC). Serial dilutions of the serum samples were mixed in vitro with rabies virus before the addition of BHK-21 cells. After 24h-incubation, cells were released by trypsin treatment, fixed and permeabilized with a p-formaldehyde solution and stained with a rabies virus nucleocapsid protein-specific antibody conjugate. The percentage of virus infection inhibition caused by specific antibodies present in the serum were evaluated in a Beckton Dickinson FACSCalibur flow cytometer. A correlation curve between the IU/ml content and the percentage of infective inhibition was built with a reference serum and the VNA titers of serum samples were obtained by extrapolation. Titers obtained by FC and standard test showed an effective pairing results (p < 0.01), with a correlation coefficient (r) = 0.7. These results permit to envisage the FC as a suitable technique to evaluate VNA in sera from immunized animals and likely in human serum samples. Nevertheless, new studies comparing FC to gold-standard techniques are required for determining the FC values of Sensibility and Specificity.     

Trypanosome infections in Glossina spp. inhabiting peridomestic agroecosystems in Nsukka area, Anambra State, Nigeria

Trypanosome infections in Glossina spp. inhabiting three peridomestic agroecosystems in Nsukka area were studied by dissection from April 1984 to July 1985. Approximately 0.65% of 4620 G. tachinoides and none of 17 G. palpalis were found with maturing or mature trypanosome infections. Of these infections, 20% were due to the Trypanosoma brucei group, 40% to the T. congolense group, and 40% to a mixture of the T. brucei and T. congolense groups. Trypanosome infection rates did not differ significantly with seasons or sex of fly, but they differed significantly with location. An apparent difference was observed in the frequency with which male and female G. tachinoides were infected by the various trypanosome species. Also there was a difference in the variety of trypanosome species encountered in the three locations. In infective flies, while the salivary gland, labrum and midgut were scantily to very heavily infected, the hypopharynx was never heavily infected. Dependence of tsetse flies on domestic pigs as the major source of blood meals, commercial activities in the area, the inherently limited vectorial capacity of palpalis group tsetse, and the fact that most flies apparently obtained their first blood meal when two to four days old, were identified as some of the factors responsible for the observed infection rates. The epizootiological and epidemiological implications of these findings are discussed.     

玉溪市红塔区旋毛虫病血清流行病学调查

玉溪市红塔区为云南省旋毛虫病抽样调查中签城市，为此，我们于2003年10月～2004年1月按全国人体重要寄生虫病现状调查实施方案，对城区两个居民点及其它农村乡镇的部分家鼠进行了血清学检测，结果报告如下。     

Seroepidemiological survey of toxoplasmosis in La Guadeloupe, French West Indies

A random survey of 1% of the total population of La Guadeloupe, French West Indies, for toxoplasmosis was carried out. Blood specimens from 3,238 individuals were collected on filter paper strips and tested for Toxoplasma antibodies by the fluorescent antibody technique. Sixty percent were positive. A gradual increase in positivity with increasing age, and high prevalence in children (50% in the 6- to 10-year age group) were observed. No differences were found among the different ethnic groups, nor among persons in different occupations. Economic status showed a highly negative correlation with antibody prevalence rates. The infection rate was not higher in individuals who consumed raw or undercooked meat, and no differences in antibody prevalence related to the sources of meat were observed. The seropositivity rates varied over a wide range (40-76%) according to the locality; higher Toxoplasma antibody rates were found in areas with higher rainfall, and toxoplasmosis prevalence rates correlated positively with mean annual rainfall but not with altitude or with rural or urban residence. A significant difference was observed between seropositivity rates when people living in houses with or without cats were compared. A higher prevalence of hookworm and Strongyloides infections--considered as evidence of closer contact with moist soil--were found in children with Toxoplasma antibodies than in age-adjusted control children without such antibodies. These results provide evidence that meat plays a negligible role in the transmission of Toxoplasma to man, and support the hypothesis that oocysts shed in cat feces are the almost exclusive mode of human infection in Guadeloupe.     

抗狂犬病病毒的初步研究

目的选取盐酸氯胺酮,重组人干扰素α1b以及人狂犬病免疫球蛋白治疗带毒犬,力图为犬伤后寻找有效治疗。方法取经过盐酸氯胺酮,重组人干扰素α1b以及人狂犬病免疫球蛋白治疗的带毒犬唾液,采用快速狂犬病酶联免疫诊断(RREID),检测唾液标本中狂犬病病毒抗原转阴率分别为36.36%,7.14%,和10.00%。结果氯胺酮治疗组与干扰素及免疫球蛋白治疗组比较,病毒抗原转阴率差异有统计学意义(P<0.05)。结论盐酸氯胺酮在处理严重的犬咬伤抗狂犬病毒上具有一定效果。     

抗狂犬病病毒N蛋白单克隆抗体的制备与鉴定

目的制备抗狂犬病病毒N蛋白单克隆抗体,为建立快速准确的狂犬病病毒抗原检测方法奠定基础。方法将狂犬病病毒Flury LEP株N基因克隆至pGEX-6P-1表达载体中,将纯化后的pGEX-6P-1-RV-N蛋白免疫BALB/c小鼠3次。取小鼠脾脏细胞和SP2/0细胞融合后,用pET-32a-RV-N重组蛋白作为筛选抗原,经3次亚克隆筛选后得到1D9、2B6、3C5、6B5及5F2 5株单克隆抗体细胞株。亚类鉴定结果表明,其中1D9、2B6、6B5 3株亚类为IgG1,3C5、5F2的亚类为IgM。间接ELISA方法检测2B6单抗细胞腹水效价可达1∶106。经Protein G亲和层析柱纯化和脱盐后可得到浓度为2.5mg/mL的高纯度的单克隆抗体。其免疫荧光试验结果表明5株单克隆抗体均能特异地与狂犬病病毒结合。结论制备的单抗具有良好的特异性和敏感性,为后期诊断方法的建立奠定了基础。