Card Agglutination Test Research Articles

A survey of sleeping sickness in parts of Benue State, Nigeria

A survey of sleeping sickness, scientifically called humanAfrican trypanosomiasis, aimed at case detection and treatment wascarried out in Gboko, Buruku, Gwer and Ushongo Local GovernmentAreas (LGAs) of Benue State, Nigeria in April 2009.A total of 820 individuals aged 2-87 years were clinically examined for palpable glands and screened for the presence of circulating anti-Trypanosoma brucei gambiense anti-bodies using the Card Agglutination Test for Trypanosomiasis (CATT) as a primaryscreening test. In-depth interviews and focus group discussions were held with village leaders and selected community members to assess their knowledge, attitude and perception (KAP) about sleeping sickness. The clinical data showed two individuals with suggestive palpable glands which upon examination of the aspirates following gland punctures weremicroscopically negative for trypanosomes. The CATT gave zero prevalence (0 %) indicating that the 820 individuals were negative. Qualitative data showed the rarity of sleeping sickness in the areas surveyed. It appears from our results that the parts of Benue State covered in the screening exercise are currently no longer endemic to sleeping sickness.We recommend more extensive population surveys taking cognisance of the remaining 19 LGAs in order to establish with certainty the currentsituation of sleeping sickness in the entire State.

An evaluation of melarsomine hydrochloride efficacy for parasitological cure in experimental infection of dairy cattle with Trypanosoma evansi in Thailand

Melarsomine hydrochloride can cure Trypanosoma evansi infection in camels at a dose of 0·25 mg/kg, but at that dose relapses occur in cattle. In our study, the efficacy of an intramuscular injection of melarsomine hydrochloride at 0·5 mg/kg was assessed in 3 normal and 3 splenectomized dairy cattle experimentally infected with a stock of T. evansi from Thailand. The animals were monitored for 5 months by haematocrit centrifugation, blood- or cerebrospinal fluid-mouse inoculation, polymerase chain reaction, the card agglutination test (CATT) for T. evansi, and the enzyme-linked immunosorbent assay‑T. evansi. Parasitological and DNA tests became and remained negative just after treatment. By the end of the experiment, CATT was negative and ELISA scores were below or very close to the cut-off value. One of the splenectomized cattle died from anaplasmosis during the experiment, but tested negative for surra. It was concluded that the parasites had been cleared from the cattle, and melarsomine hydrochloride at 0·5 mg/kg can be recommended for treatment against T. evansi infection in dairy cattle in Thailand. Further work is necessary to validate the efficacy of the treatment in the event of confirmed CSF-infection.

Diversity of response to Trypanosoma brucei gambiense infections in the Forecariah mangrove focus (Guinea): perspectives for a better control of sleeping sickness

At a time when human African trypanosomiasis (HAT) elimination again seems a reachable goal in many parts of sub-Saharan Africa, it is becoming increasingly important to characterise the factors involved in disease resurgence or maintenance to develop sustainable control strategies. In this study conducted in the Forecariah mangrove focus in Guinea, HAT patients and serological suspects (SERO) were identified through mass screening of the population with the Card Agglutination Test for Trypanosomiasis (CATT) and were followed up for up to 2 years. Analysis of the samples collected during the follow-up of HAT patients and SERO was performed with PCR (TBR1/TBR2) and the trypanolysis serological test (TL) in order to clarify the role played by these individuals in the epidemiology of HAT. PCR positivity was higher in TL + than in SERO TL − (50% vs. 18%, respectively). Whereas CATT plasma titres decreased both in treated HAT patients and SERO TL −, SERO TL + maintained high CATT titres. Four out of 17 SERO TL + developed HAT during the study. These results strongly suggest that SERO TL + individuals are asymptomatic carriers. In the context where disease prevalence is sufficiently low, treating SERO TL + individual may thus be of crucial importance in order to cut transmission.

Application of loop-mediated isothermal amplification (LAMP) of the random insertion mobile element (RIME - LAMP) to diagnose camel Trypanosomiasis in Sudan

Control of Trypanosomiasis is dependent on accurate diagnosis and treatment of infected patients or animals. Highly sensitive tests are available for serological screening but the sensitivity of parasitological confirmatory tests remains insufficient and needs to be improved. Ongoing research is opening perspectives for a new generation of field diagnostics. This study aimed to apply and investigate new diagnostic technique loop-mediated isothermal amplification (LAMP) of the random insertion mobile element (RIME - LAMP) to diagnose camel Trypanosomiasis in Sudan. Extracted DNA from camels was used to detect Trypanosoma evansi infection in camels using RIME-LAMP technique. A total of 368 DNA samples positive reactor with card agglutination test for Trypanosomiasis (CATT T. evansi) was tested using RIME-LAMP. A total of 208 samples reacted positive (56.52%) using RIME – LAMP whereas only 17 samples were positive (6.34%) using parasitological methods. RIME-LAMP helps increase the probability of detecting the positive cases of camel Trypanosomiasis and it was found to be one useful and alternative molecular diagnostic tool for the detection of T. evansi infections. Key words: Sudan, loop-mediated isothermal amplification (LAMP) - random insertion mobile element (RIME - LAMP), camel, Trypanosoma evansi.

Latent Trypanosoma brucei gambiense foci in Uganda: a silent epidemic in children and adults?

Trypanosoma brucei gambiense sleeping sickness follows a long asymptomatic phase and persists in ancient foci from which epidemic clinical disease arises. A putative focus of T. b. gambiense infections has been identified, initially in mothers and young children, on the Lake Albert shoreline of Western Uganda leading to mass screening of 6207 individuals in September 2008. T. b. gambiense infections were identified by Card Agglutination Test for Trypanosomiasis (CATT) and sub-species-specific PCR although parasitological methods failed to confirm any patent trypanosome infections. In April 2009, CATT positives were re-visited; diagnosis of individuals by CATT and PCR was unstable over the two time points and parasites remained undetected, even using mini Anion Exchange Centrifugation Technique (mAECT). These observations suggest the possibility of a silent focus of disease, where all infected individuals are in a latent stage, and highlight our limited understanding of the local natural history and disease progression of T. b. gambiense in children and adults.

First evidence that parasite infecting apparent aparasitemic serological suspects in human African trypanosomiasis are Trypanosoma brucei gambiense and are similar to those found in patients

Thanks to its sensitivity and its ease of use in the field, the card agglutination test for trypanosomiasis (CATT) is widely used for serological screening of Trypanosoma brucei gambiense human African trypanosomiasis (HAT). Positive subjects are then examined by microscopy to confirm the disease. However, the CATT exhibits false-positive results raising the question of whether CATT-positive subjects who are not confirmed by microscopic detection of trypanosomes (SERO) are truly exposed to T.b. gambiense infection. For this purpose, we applied microsatellite genotyping on DNA extracted from blood of both HAT confirmed patients and SERO subjects in Guinea and Côte d’Ivoire since microsatellite genotyping has proved useful for the study of T.b. gambiense genetic diversity. Problems of amplification failures raise the question of the sensitivity of microsatellite markers when applied on biological samples especially from SERO subjects for who low blood parasitaemia are suspected. Nevertheless, we have shown that the trypanosomes from SERO individuals that have been genotyped belong to T.b. gambiense group 1 and were identical to those found in HAT patients. These results constitute the first evidences that at least some SERO are indeed infected by T.b. gambiense group 1 and that they may constitute a human reservoir of parasite in HAT foci. Whether these individuals should undergo treatment remains an open question as long as their role in HAT transmission is unknown. Our results strongly recommend the follow-up of such subjects to improve control strategies.

Revisiting the Immune Trypanolysis Test to Optimise Epidemiological Surveillance and Control of Sleeping Sickness in West Africa

BackgroundBecause of its high sensitivity and its ease of use in the field, the card agglutination test for trypanosomiasis (CATT) is widely used for mass screening of sleeping sickness. However, the CATT exhibits false-positive results (i) raising the question of whether CATT-positive subjects who are negative in parasitology are truly exposed to infection and (ii) making it difficult to evaluate whether Trypanosoma brucei (T.b.) gambiense is still circulating in areas of low endemicity. The objective of this study was to assess the value of the immune trypanolysis test (TL) in characterising the HAT status of CATT-positive subjects and to monitor HAT elimination in West Africa.Methodology/Principal FindingsTL was performed on plasma collected from CATT-positive persons identified within medical surveys in several West African HAT foci in Guinea, Côte d'Ivoire and Burkina Faso with diverse epidemiological statuses (active, latent, or historical). All HAT cases were TL+. All subjects living in a nonendemic area were TL−. CATT prevalence was not correlated with HAT prevalence in the study areas, whereas a significant correlation was found using TL.Conclusion and SignificanceTL appears to be a marker for contact with T.b. gambiense. TL can be a tool (i) at an individual level to identify nonparasitologically confirmed CATT-positive subjects as well as those who had contact with T.b. gambiense and should be followed up, (ii) at a population level to identify priority areas for intervention, and (iii) in the context of HAT elimination to identify areas free of HAT.

Factors influencing the sero-prevalence of Trypanosoma brucei gambiense sleeping sickness in Juba District, Central Equatoria State, Southern Sudan

A surveillance of the Gambian type of Human African Trypanosomosis (HAT) conducted in Juba area using the Card Agglutination Test for Trypanosomosis (CATT) showed that 257 (11.1%) out of 2322 individuals were sero-positive. The sero-positive rate in the pooled adults was higher but not significanty different from that of the pooled children. The adult females sero-prevalence rate was significantly higher than those of adult males, male or female children. There were no significant differences in the sero-prevalence rates between adult men and male or female children. The internally-displaced group and the military personnel showed statistically higher sero-positive rates than the resident groups regardless of the presence or absence of the only extant tsetse species, Glossina fuscipesfuscipes. The proportions of sero-positives differed significantly between locations in the study area. The respondents examined along the riverine vegetation had a statistically higher encounter with the disease than those in the derived savanna and the open savanna woodland. There was no significant correlation between the density of G. fuscipes fuscipes and the incidence of Trypanosoma bruceigambiense. Key words: CATT, sero-prevalence, sleeping sickness, HAT, Gambian type.

Human African trypanosomiasis in endemic focus of Abraka, Nigeria

Objective To investigated the prevalence of human African trypanosomiasis (HAT), a neglected tropical disease caused by Trypanosoma brucei gambiens in an endemic focus of Nigeria, as it relates to age, sex and occupational differences. Methods A total of 474 human subjects were screened using card agglutination test for trypanosomiasis kit. Positive samples were further investigated for parasite positivity in blood/serum and cerebrospinal fluid (CSF). Results Of the 474 screened, 44(9.3%) were seropositive with seroprevalence of 22(9.6%) in Urhouka, 14(9.5%) in Umeghe and 8(7.9%) for Ugonu. The number of seropositives, observed for weakly, moderately and strongly positives for the three communities were 4, 7 and 11 in Urhouka, 4, 5 and 5 in Umeghe and 3, 2 and 3 in Ugonu respectively. Among the 16 volunteers with detected parasite in their blood, 4 of them were weakly positive, 5 of them were moderately positive and 7 of them strongly positive. 4 volunteers from Urhouka community were found parasites in their CSF and they were all strongly positive. The difference between the seroprevalence of males and females was not statistically significant ( OR=1.14, 95% CI=0.37–3.4, P>0.05). The prevalence difference between age group 21–30 years old and the youngest and oldest age groups was statistically significant ( OR=3.5, 95% CI=1.08–12.57, P<0.05) but not significant for other age categories ( P>0.05). It was observed that farmers had significantly higher prevalence of HAT infection as well as greater risk of Trypanosoma brucei gambiense infection than inhabitants with other occupations ( OR=3.25, 95% CI=0.99–11.79, P<0.05). Conclusions Human activities such as farming and visits to the river have been identified as major risk factors to HAT. Also the breakdown of HAT control program has been advanced for the rise in HAT in Abraka, an endemic focus in Nigeria.

Diagnostic Accuracy of Methods for Detecting Anaplasma Marginale Infection in Lactating Dairy Cattle of Puerto Rico

Bovine anaplasmosis (BA) is a hemoparasitic disease of great importance in cattle within the tropical and subtropical regions of the world. Control programs for BA require accurate diagnostic assays but validation can be challenging because the true disease status of all animals is frequently not known with certainty. The objective of this study was to estimate the accuracy of assays for detection of Anaplasma marginale infection in lactating dairy cattle of Puerto Rico using Bayesian methods without a perfect reference test. There were 2,331 cattle with complete diagnostic results sampled from 79 herds, and the prevalence of BA was estimated as 22% (95% probability interval [PI]: 19-25%). The sensitivity (Se) and specificity (Sp) of a major surface protein 5 competitive enzyme-linked immunosorbent assay (MSP-5 cELISA) were estimated as 99% (95% PI: 96-100%) and 89% (95% PI: 87-92%), respectively. The Se and Sp of a quantitative polymerase chain reaction (qPCR) were 67% (95% PI: 60-74%) and 99% (95% PI: 99-100%). The Se and Sp of a card agglutination test were 34% (95% PI: 29-39%) and 99% (95% PI: 99-100%). Area under the receiver-operating characteristic curve for the MSP-5 cELISA was 0.748 (95% PI: 0.71-0.79). The MSP-5 cELISA appears to be the test of choice for screening cattle for subclinical BA based on the high estimated Se, rapidity of results, relative low cost, and ease of standardization.

A new format of the CATT test for the detection of Human African Trypanosomiasis, designed for use in peripheral health facilities

To test the reproducibility and thermostability of a new format of the Card-Agglutination Test for Trypanosomiasis (CATT) test for Human African Trypanosomiasis (HAT), designed for use at primary health care facility level in endemic countries. A population of 4217 from highly endemic villages was screened using the existing format of the CATT test (CATT-R250) on whole blood. All those testing positive (220) and a random sample of negatives (555) were retested in the field with the new format (CATT-D10). Inter-format reproducibility was assessed by calculating kappa. All samples testing positive on whole blood with either method were further evaluated in Belgium by CATT titration of serum by two observers, using both old and new format. CATT-D10 test kits were incubated under four temperature regimens (4, 37, 45 degrees C and fluctuating) with regular assessments of reactivity over 18 months. Inter-format reproducibility of CATT-D10 vs. CATT-R250 on whole blood performed by laboratory technicians in the field was excellent with kappa values of 0.83-0.89. Both inter- and intra-format reproducibility assessed by CATT titration were excellent, with 96.5-100% of all differences observed falling within the limits of +/-1 titration step. After 18 months, reactivity of test kits incubated under all four temperature regimens was still well above the minimum threshold considered acceptable. The CATT-D10 is thermostable and can be used interchangeably with the old format of the CATT test. It is highly suitable for use in peripheral health facilities in HAT-endemic countries.

Serological and parasitological survey of dourine in the Arsi–Bale highlands of Ethiopia

This study was conducted from August 2005 to January 2007 to determine prevalence and distribution of dourine in horses and to investigate the occurrence of clinical and carrier cases in donkeys and mules in the Arsi-Bale highlands. Study methodology was based on questionnaire, serological, clinical and parasitological survey. The questionnaire indicated that dourine is a major health problem of equines in the Arsi-Bale highlands. Though dourine is commonly observed throughout the year, it has a seasonal character and occurs mostly during the breeding season from June to late September. Serological screening of 646 horses showed a seroprevalence of 184 (28%), 161 (25%) and 125 (19%) for card agglutination test for trypanosomosis, LATEX and enzyme-linked immunosorbent assay, respectively. Risk factors were parity number, previous history of abortion and body condition score. No trypanosomes could be detected by Giemsa staining or by haematocrit centrifugation technique. Ten puppies inoculated with blood samples, genital washes and oedematous fluids remained parasitologically negative. Different characteristic signs of dourine were observed. During the genital stage, mares showed vaginal oedema, discharge and presence of depigmented scars over the external genitalia. In stallions, oedema of the scrotum and prepuce, prepucial and urethral discharge, and ulceration of the genital mucosae mainly of the penile were observed. In both sexes, lameness in one or both legs, partial dragging and stiffness of the hind legs and incoordination were the dominant signs observed as nervous form of the disease.

Towards a New Reference Test for Surra in Camels

Current serological diagnosis of Trypanosoma evansi infection in camels is based on the native variable antigen type RoTat 1.2. The goal of this study was to develop a novel serological diagnostic test based on a nonvariable protein and freed from the use of rats or mice for its production. An enzyme-linked immunosorbent assay using a recombinant extracellular domain of invariant surface glycoprotein 75 (ELISA/rISG75) was developed and tested on a collection of 184 camel sera. The results were compared to those obtained from three established antibody detection tests based on variable surface glycoprotein RoTat 1.2: an ELISA for T. evansi (ELISA/T. evansi), a card agglutination test for trypanosomiasis (CATT/T. evansi), and an immune trypanolysis (TL) assay. The ELISA/rISG75 and the ELISA/T. evansi showed a sensitivity of 94.6% (95% confidence interval [CI], 87.8 to 98.2%, at 19% positivity cutoff value) and 98.9% (95% CI, 94.1 to 99.8, at 12% positivity cutoff value), respectively. The ELISA/rISG75 had 100% specificity (CI, 95.9 to 100%), while the ELISA/T. evansi showed 98.9% specificity (CI, 95.9 to 100%). The ELISA/rISG75 demonstrated an almost perfect agreement with the TL assay, the CATT/T. evansi, and the ELISA/T. evansi, with kappa scores of at least 0.94. The ELISA/rISG75, having a performance comparable to that of the gold standard (the TL assay) and being independent of antigenic variation, may become a new reference test for surra in camels. It opens avenues for the diagnosis of T. evansi infections in other hosts as well as for the development of a pan-Trypanozoon test for detection of Trypanosoma brucei brucei, T. b. gambiense, T. b. rhodesiense, T. evansi, and T. equiperdum.

A Comparison Of Methods Of Investigating Human Sleeping Sickness (Human African Trypanosomiasis: Hat) In Nigeria

The difficulty in the diagnosis of Human African Trypanosomiasis (HAT) remains a major set-back in the control of the disease. Without systematic screening of a population at risk and confirmation of diagnosis of the disease, all infected people who remain untreated will die even in the face of massive immune responses. In this study, card agglutination test for trypanosomiasis (CATT) screening, blood, lymph node juice (LNJ) and cerebrospinal fluid (CSF) studies were conducted among 852 subjects aged between 15 and 65 years and the results compared. One hundred and twenty two (14.3%), 84 (9.9%) and 73 (8.6%) subjects were CATT positive by whole blood, plasma dilution 1:2 and 1:4 respectively. Twelve (1.4%) cases were confirmed that were seropositive by the plasma 1:4 dilution with 2 (0.2%) in the early haemolymphatic phase I and 10 (1.2%) in the late CNS phase II. Of the confirmed, all were positive by Haematocrit concentration technique (HCT), 10 (1.2%) by CSF microscopy, 6 (0.2%) by LNJ microscopy, 1(0.8%) by Giemsa thick film and none (0%) by thin film. There were twenty-two (18.0%) malaria cases seen among the unconfirmed cases. There were 24 (19.7%) cases of loiasis, 10(1.2%) of which occurred concomitantly with trypanosomiasis which was diagnosed in 6(4.9%) patients who were Phase1, 4(3.3%) patients in phase 11 and 14(1.4%) were among the unconfirmed. The pattern of concomitant and non concomitant infections among seropositive and confirmed subjects reported here warrants further study, in order to document reliable indices of suspicion among serosuspects when confirmation proves difficult. Keywords : Trypanosomiasis, diagnostic methods, concomitant, non concomitant infections Journal of Mining and Geology Vol. 5 (1&2) 2006: pp. 13-22

Sleeping Sickness Surveillance In The Abraka Sleeping Sickness Focus, Nigeria

Humans are the main reservoir hosts for gambiense sleeping sickness. They are therefore essential for the sustainance of its endemicity and reemergence of epidemics in many disease foci within sub- Saharan Africa. To investigate the epidemiological and clinical significance of reservoir hosts in the Abraka Sleeping Sickness Focus (ASSF), this survey was conducted between 8th April and May 11th 2002 in seven endemic villages with an overall population of 13,683. Pretested structured questionnaires were administered following informed consent on 2437 participants (1061 males and 1376 females) to assess knowledge and beliefs about the disease. Card Agglutination Test for Trypanosomes (CATT) screening was performed using whole blood on 1568 (11.6%) subjects of the overall population. Study participants were aged between less than 1 year and over 61 years. Confirmation of sleeping sickness (ss) was by the detection of trypanosomes in blood, body fluids and biopsy tissues. Thirteen (0.8%) seropositive subjects were parasitologically confirmed and treated with melasoprol at the Baptist Medical Centre (BMC) Eku. One (0.06%) patient died during the course of treatment. Forty-two (0.3%) subjects dropped out from the study while 128 (0.9%) seropositive and aparasitaemic subjects are currently being followed up. Five hundred and twenty (21.3%) of the 2,437 subjects interviewed reported having heard about the disease, while only 316 (12.9) had correct knowledge about the vector for the disease. Three hundred and sixty six (15.0%) believe those with the disease should remain in hiding, 422 (17.3%) believe the disease is a taboo while only 592 (25.3%) believe the disease is treatable by orthodox means. Our result provides data on active case detection and suggests the need for the formulation of health policies aimed at promoting compatibility of beliefs and knowledge about sleeping sickness with appropriate treatment seeking behaviour in the area. This approach will highlight acceptable levels of effective disease suppression with the involvement and cooperation of the affected communities. Keywords : Gambiense sleeping sickiness, CATT screening, Melasoprol, Abraka, Nigeria. Annals of Biomedical Science Vol. 2 (1) 2003: pp. 20-29

Cost-effectiveness of Algorithms for Confirmation Test of Human African Trypanosomiasis

The control of Trypanosoma brucei gambiense human African trypanosomiasis (HAT) is compromised by low sensitivity of the routinely used parasitologic confirmation tests. More sensitive alternatives, such as mini-anion exchange centrifugation technique (mAECT) or capillary tube centrifugation (CTC), are more expensive. We used formal decision analysis to assess the cost-effectiveness of alternative HAT confirmation algorithms in terms of cost per life saved. The effectiveness of the standard method, a combination of lymph node puncture (LNP), fresh blood examination (FBE), and thick blood film (TBF), was 36.8%; the LNP-FBE-CTC-mAECT sequence reached almost 80%. The cost per person examined ranged from euro1.56 for LNP-FBE-TBF to euro2.99 for LNP-TBF-CTC-mAECT-CATT (card agglutination test for trypanosomiasis) titration. LNP-TBF-CTC-mAECT was the most cost-effective in terms of cost per life saved. HAT confirmation algorithms that incorporate concentration techniques are more effective and efficient than the algorithms that are currently and routinely used by several T.b. gambiense control programs.

Evaluation of serodiagnostic tests for T.b. gambiense human African trypanosomiasis in southern Sudan

A survey was conducted in a low-endemic and in a non-endemic area of Sudan to evaluate the specificity and efficiency of different serological antibody detection techniques for Trypanosoma brucei gambiense. Comparisons were made of the card agglutination test for trypanosomiasis (CATT) on diluted blood, on diluted plasma and on eluates from blood dried on filter paper, the LATEX test on diluted plasma and an ELISA on diluted plasma and filter paper. The specificities of all the serological tests were not significantly different from CATT on diluted blood (99.5%). The specificity of CATT on diluted blood was similar (99.3%). The highest sensitivities (100%) were observed with CATT on diluted blood and with CATT and LATEX on diluted plasma. CATT on diluted blood was more cost-efficient than the classic test, CATT on whole blood.

Diagnostic Characterization of a Feral Swine Herd Enzootically Infected withBrucella

Eighty feral swine were trapped from a herd that had been documented to be seropositive for Brucella and which had been used for Brucella abortus RB51 vaccine trials on a 7,100-hectare tract of land in South Carolina. The animals were euthanized and complete necropsies were performed. Samples were taken for histopathology, Brucella culture, and Brucella serology. Brucella was cultured from 62 (77.5%) animals. Brucella suis was isolated from 55 animals (68.8%), and all isolates were biovar 1. Brucella abortus was isolated from 28 animals (35.0%), and isolates included field strain biovar 1 (21 animals; 26.3%), vaccine strain Brucella abortus S19 (8 animals, 10.0%), and vaccine strain Brucella abortus RB51 (6 animals, 7.5%). Males were significantly more likely to be culture positive than females (92.9% vs. 60.6%). Thirty-nine animals (48.8%) were seropositive. Males also had a significantly higher seropositivity rate than females (61.9% vs. 34.2%). The relative sensitivity rates were significantly higher for the standard tube test (44.6%) and fluorescence polarization assay (42.6%) than the card agglutination test (13.1%). Lesions consistent with Brucella infection were commonly found in the animals surveyed and included inflammatory lesions of the lymph nodes, liver, kidney, and male reproductive organs, which ranged from lymphoplasmacytic to pyogranulomatous with necrosis. This is the first report of an apparent enzootic Brucella abortus infection in a feral swine herd suggesting that feral swine may serve as a reservoir of infection for Brucella abortus as well as Brucella suis for domestic livestock.

HUMAN TRYPANOSOMIASIS CAUSED BY TRYPANOSOMA EVANSI IN A VILLAGE IN INDIA: PRELIMINARY SEROLOGIC SURVEY OF THE LOCAL POPULATION

After discovery of the first recorded case of human infection with Trypanosoma evansi, serologic screening of 1,806 persons from the village of origin of the patient in India was performed using the card agglutination test for trypanosomiasis and T. evansi. A total of 410 (22.7%) people were positive by whole blood, but only 81 were confirmed positive by serum. However, no trypanosomes were detected in the blood of 60 people who were positive at a high serum dilution. The results probably indicate frequent exposure of the human population to T. evansi in the study area, which suggests frequent vector transmission of parasites to humans. Although T. evansi is not infective for humans, a follow-up of seropositive persons is required to observe the evolution of human infection with this parasite.

Diagnosing human African trypanosomiasis in Angola using a card agglutination test: observational study of active and passive case finding strategies

Objective To assess the operational feasibility of detecting human African trypanosomiasis by active and passive case finding using the card agglutination test with serial dilution of serum to guide treatment.Setting...