Development and evaluation of a rapid dipstick assay for serodiagnosis of acute human brucellosis

A dipstick assay for the detection of brucella-specific immunoglobulin M antibodies was evaluated with 707 sera from 247 laboratory-confirmed brucellosis patients and 342 control sera from brucellosis-free individuals. These sera were collected from six different countries. The assay was found to be highly sensitive and specific. In addition, the test is easy to use and does not require specialized training or equipment, and the components are stable without a requirement for refrigeration. All of these factors make the test ideal for developing countries and rural settings

Immunochromatographic Brucella-specific immunoglobulin M and G lateral flow assays for rapid serodiagnosis of human brucellosis

To fulfill the need for a simple and rapid diagnostic test for human brucellosis, we used the immunochromatographic lateral flow assay format to develop two assays, one for the detection of Brucella-specific immunoglobulin M (IgM) antibodies and one for the detection of Brucella-specific IgG antibodies. The diagnostic values of these tests were examined. The tests are shown to detect acute, persistent, and relapsing disease and can be used to monitor treatment. The sensitivity of Brucella IgM and IgG flow assays calculated for the combined assay results is 96%, and specificity amounts to 99%. The flow assay requires neither specialized training nor equipment, the assay is very easy to perform and to read, and the components are stable without a requirement for refrigeration and well standardized. Together these characteristics indicate that the Brucella IgM and IgG flow assays are ideal for use in clinical settings in rural and suburban areas in which brucellosis is endemic

Comparison of a dipstick assay for detection of Brucella-specific immunoglobulin M antibodies with other tests for serodiagnosis of human brucellosis.

A dipstick assay for the detection of Brucella-specific immunoglobulin M (IgM) antibodies was evaluated by studying the serological response of 133 cultures and or serologically confirmed patients with brucellosis in its different stages along with those of 34 healthy controls. As regards patients with illness less than 3 months in duration, 93.1% tested positive by the dipstick assay, a percentage similar to that obtained in the standard serum agglutination test (SAT) (92.0%), somewhat lower than that obtained by culture (100%) and higher than that obtained by IgM enzyme-linked immunosorbent assay (ELISA) (80.5%). SAT was the most sensitive test (87.0%) for patients with illness more than 3 months in duration, followed by culture (50%), the dipstick assay (28.3%), and IgM ELISA (7.5%). The results demonstrate that the dipstick assay could well be used in the serodiagnosis of patients with acute brucellosis, as well as to identify patients with a long history of the illness. Under laboratory conditions this test has the advantage of being quick and IgM antibody-specific

Comparative performance of lateral flow immunochromatography, iELISA and Rose Bengal tests for the diagnosis of cattle, sheep, goat and swine brucellosis

Background Brucellosis is a world-wide extended zoonosis that causes a grave problem in developing economies. Animal vaccination and diagnosis are essential to control brucellosis, and the need for accurate but also simple and low-cost tests that can be implemented in low-infrastructure laboratories has been emphasized. Methodology We evaluated bovine, sheep, goat and swine lateral flow immunochromatography assay kits (LFA), the Rose Bengal test (RBT) and a well-validated protein G indirect ELISA (iELISA) using sera of Brucella culture-positive and unvaccinated brucellosis free livestock. Sera from cattle vaccinated with S19 and RB51 brucellosis vaccines were also tested. Finally, we compared RBT and LFA using sera of white Fulani cattle of unknown bacteriological status from a brucellosis endemic area of Nigeria. Results and conclusions Although differences were not statistically significant, RBT showed the highest values for diagnostic sensitivity/specificity in cattle (LFA, 96.6/98.8; RBT, 98.9/100; and iELISA, 96.6/100) and the iELISA yielded highest values in sheep (LFA, 94.0/100; RBT, 92.0/100; iELISA, 100/100), goats (LFA, 95.7/96.2; RBT, 97.8/100; iELISA, 100/100) and pigs (LFA, 92.3/100; RBT, 92.3/100; iELISA, 100/100). Vaccine S19 administered subcutaneously interfered in all tests but conjunctival application minimized the problem. Although designed not to interfere in serodiagnosis, vaccine RB51 interfered in LFA and iELISA but not in the RBT. We found closely similar apparent prevalence results when testing the Nigerian Fulani cattle by RBT and LFA. Although both RBT and LFA (showing similar diagnostic performance) are suitable for small laboratories in resource-limited areas, RBT has the advantage that a single reagent is useful in all animal species. Considering these advantages, its low cost and that it is also useful for human brucellosis diagnosis, RBT might be a good choice for resource-limited laboratories