Comparison of a Flow Assay for Brucellosis Antibodies with the Reference cELISA Test in West African Bos indicus

Brucellosis is considered by the Food and Agricultural Organisation and the World Health Organisation as one of the most widespread zoonoses in the world. It is a major veterinary public health challenge as animals are almost exclusively the source of infection for people. It is often undiagnosed in both human patients and the animal sources and it is widely acknowledged that the epidemiology of brucellosis in humans and animals is poorly understood, particularly in sub-Saharan Africa. It is therefore important to develop better diagnostic tools in order to improve our understanding of the epidemiology and also for use in the field for disease control and eradication. As with any new diagnostic test, it is essential that it is validated in as many populations as possible in order to characterise its performance and improve the interpretation of its results. This paper describes a comparison between a new lateral flow assasy (LFA) for bovine brucellosis and the widely used cELISA in a no gold standard analysis to estimate test performance in this West African cattle population. A Bayesian formulation of the Hui-Walter latent class model incorporated previous studies' data on sensitivity and specificity of the cELISA. The results indicate that the new LFA is very sensitive (∼87%) and highly specific (∼97%). The analysis also suggests that the current cut-off of the cELSIA may not be optimal for this cattle population but alternative cut-offs did not significantly change the estimates of the LFA. This study demonstrates the potential usefulness of this simple to use test in field based surveillance and control which could be easily adopted for use in developing countries with only basic laboratory facilities

Brucellosis is not a major cause of febrile illness in patients at public health care facilities in Binh Thuan Province, Vietnam

To determine the presence of brucellosis among patients with acute febrile illness at health care facilities in Binh Thuan province, Vietnam. A retrospective seroepidemiological study on serum samples collected at 13 not adjacent health care facilities using the Rose Bengal test as a rapid screening test and the Brucella IgM/IgG flow assay as a simple confirmatory test. The seroprevalence in the Rose Bengal test among 406 patients presented with acute undifferentiated fever was 14.8%. Seven of the 64 Rose Bengal test positive samples reacted weakly (1+) positive in the Brucella IgM/IgG flow assay. No seroconversion was observed. Brucellosis is not a major cause of morbidity in Binh Thuan provinc

Agglutinating antibodies against pathogenic Leptospira in healthy dogs and horses indicate common exposure and regular occurrence of subclinical infections

In order to get insight in the level of exposure to pathogenic Leptospira under the moderate sea climate conditions in the Netherlands, healthy dogs and horses were tested for antibodies using the Microscopic Agglutination Test (MAT). 55% of 198 dogs tested had agglutinating antibodies against one or more pathogenic serovars with serovar Copenhageni, the common cause of Weil's disease in dogs and humans, being predominant. Of a total 112 horses tested 79% had agglutinating antibodies against one or more pathogenic serovars, again with serovar Copenhageni predominating. Some dogs may have been vaccinated, but the low prevalence of anti-serovar Canicola antibodies and the results of an unvaccinated group suggest that this did not really influence the outcome. Horses, however, are never vaccinated. Results demonstrate that exposure to, and subclinical infections with, serovar Copenhageni and other pathogenic serovars commonly occur in dogs and horses in the Netherlands. Humans share part of their biotope with these species and are therefore also exposed, although probably to a lesser extent as a result of their less intimate contact with the environment

The evaluation of a user-friendly lateral flow assay for the serodiagnosis of human brucellosis in Kazakhstan

Serum samples from all patients with culture-confirmed brucellosis including those with chronic disease from Kazakhstan tested positive in the serum agglutination test for titers > or = 1:25 and reacted in the Brucella immunoglobulin M/immunoglobulin G lateral flow assay (LFA) confirming the high sensitivity of these assays. The strong reactivity in the LFA observed for the majority (92.1%) of the samples from the patients with culture-confirmed brucellosis together with the user-friendliness of the assay procedure makes the LFA ideal for the confirmation of brucellosis in endemic areas in Kazakhstan. The Rose Bengal test lacked sensitivity in particular for patients with chronic brucellosis therefore limiting its value as a quick screening assay. The study emphasizes the importance of the LFA as a useful, rapid, and easy-to-perform tool in the diagnostic testing of brucellosi

Application of a point-of-care test for the serodiagnosis of typhoid fever in Nigeria and the need for improved diagnostics

There is an urgent need for affordable point-of-care diagnostics for the differentiation of febrile illnesses and the confirmation of typhoid in endemic countries. Blood samples were collected from febrile patients with clinical suspicion of typhoid and screened for typhoid fever using the Widal and Typhi Dri Dot tests, while stool and blood samples were screened for Salmonella Typhi using the culture method as well as PCR as a confirmatory test. A high proportion of febrile patients from Lagos with clinical suspicion of typhoid fever reacted positively in a simple and rapid latex agglutination assay for typhoid fever, indicating that this illness is a common and presumably under-diagnosed health problem in this metropolis. Seropositivity was 19.2% in the rapid test compared with 22.9% in the classical Widal test. The confirmation of typhoid in these seropositive patients appeared cumbersome because of negative blood cultures and low DNA yield in molecular testing. A review of the literature revealed that in Nigeria seroprevalence rates can be high in the normal population and that pathogens other than S. Typhi are often isolated from the blood of seropositive febrile patients. The simplicity and the relatively high specificity (97.8%) of the rapid test as determined in a study performed in Indonesia calls for a further validation of this promising test for use in Afric

Latex based, rapid and easy assay for human leptospirosis in a single test format

Leptospirosis is an often severe disease which requires prompt treatment. Laboratory testing is required to reach a valid diagnosis. An agglutination assay for the detection of Leptospira-specific antibodies consisting of individually wrapped agglutination cards containing a stable, dried detection reagent is evaluated. The assay is simply performed by suspending the dried reagent with a drop of serum. The result is obtained within 30 s. The sensitivity of the assay varied with the stage of the disease and was 72.3% for samples collected during the first 10 days of the illness and 88.2% for samples collected at a later stage. The specificity was 93.9% and 89.8%, respectively. These characteristics make the test ideal for use in areas where the disease is common and where laboratory support is not routinely availabl