The Rose Bengal Test in Human Brucellosis: A Neglected Test for the Diagnosis of a Neglected Disease

Brucellosis is a highly contagious zoonosis affecting livestock and human beings. The human disease lacks pathognomonic symptoms and laboratory tests are essential for its diagnosis. However, most tests are difficult to implement in the areas and countries were brucellosis is endemic. Here, we compared the simple and cheap Rose Bengal Test (RBT) with serum agglutination, Coombs, competitive ELISA, Brucellacapt, lateral flow immunochromatography for IgM and IgG detection and immunoprecipitation with Brucella proteins. We tested 208 sera from patients with brucellosis proved by bacteriological isolation, 20 contacts with no brucellosis, and 1559 sera of persons with no recent contact or brucellosis symptoms. RBT was highly sensitive in acute and long evolution brucellosis cases and this related to its ability to detect IgM, IgG and IgA, to the absence of prozones, and to the agglutinating activity of blocking IgA at the pH of the test. RBT was also highly specific in the sera of persons with no contact with Brucella. No test in this study outperformed RBT, and none was fully satisfactory in distinguishing contacts from infected patients. When modified to test serum dilutions, a diagnostic titer >4 in RBT resulted in 87.4% sensitivity (infected patients) and 100% specificity (contacts). We discuss the limitations of serological tests in the diagnosis of human brucellosis, particularly in the more chronic forms, and conclude that simplicity and affordability of RBT make it close to the ideal test for small and understaffed hospitals and laboratories

Poor performance of the rapid test for human brucellosis in health facilities in Kenya

Human brucellosis is considered to be an important but typically under-diagnosed cause of febrile illness in many low and middle-income countries. In Kenya, and throughout East Africa, laboratory diagnosis for the disease is based primarily on the febrile antigen Brucella agglutination test (FBAT), yet few studies of the diagnostic accuracy of this test exist. Assessment of the performance of the FBAT is essential for its appropriate clinical use, as well as for evaluating surveillance data reported by public health systems. To assess FBAT performance, we collected sera from people with symptoms compatible with brucellosis attending two health facilities in Busia County, Kenya. Sera were tested using the FBAT and results compared with those from the Rose Bengal Test (RBT), an assay with well-known performance characteristics. Positives on either test were confirmed using the classical serum agglutination test (SAT)-Coombs test combination and a rapid IgM/IgG lateral flow immunochromatography assay (LFA). A questionnaire focussing on known risk factors for exposure to Brucella spp. was also conducted, and relationships with FBAT positivity examined using logistic regression. Out of 825 recruited individuals, 162 (19.6%) were classified as positive using the FBAT. In contrast, only eight (1.0%) were positive using the RBT. Of the 162 FBAT positives, one (0.62%) had an atypical agglutination in SAT and three (1.9%) showed low Coombs titres. Out of 148 FBAT positive individuals tested using the LFA, five (3.4%) were IgM positive and none were IgG positive. Poor or no correlation was observed between FBAT results and most established risk factors for Brucella infection. We observed substantial disagreement between the FBAT and a number of well-known serological tests, with the majority of reactive FBAT results appearing to be false positives. Poor FBAT specificity, combined with a lack of confirmatory testing, strongly suggests overdiagnosis of brucellosis is common in this low prevalence setting. This is expected to have important economic impacts on affected patients subjected to the long and likely unnecessary courses of multiple antibiotics required for treatment of the disease

The State Language of Kazakhstan and Multilingualism

The article deals with some actual problems of real bilingualism (polylingualism) in modern Kazakhstan.One of the most important aspects of the Kazakhstani society of economic and social modernization is the policy in the field of language. In the modern world, multilingual and multicultural, the problem of language conjugation is more urgent than ever, the search for effective and viable programs in the field of languageson the consolidation of societies. Integration of Kazakhstan into the world community depends today on the realization and realization of a simple truth: the world is open to those who can master new knowledge through mastering the dominant languages. In Kazakhstan the notions of “bilingualism” and “polylingualism” mean the equality of languages.It is quite natural that bilingualism (polylingualism) gains more and more importance in our republic

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