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A lateral flow device (LFD) for the detection of all seven serotypes of foot-and-mouth disease virus (FMDV) was developed using a monoclonal antibody (Mab 1F10) shown to be pan-reactive to FMDV strains of each serotype by ELISA. The performance of the LFD was evaluated in the laboratory on suspensions of vesicular epithelia (304 positive and 1003 negative samples) from suspected cases of vesicular disease collected from 86 countries between 1965 and 2008 and negative samples collected from healthy animals. The diagnostic sensitivity of the LFD for FMDV was similar at 84% compared to 85% obtained by the reference method of antigen ELISA, and the diagnostic specificity of the LFD was approximately 99% compared to 99.9% for the ELISA. The device recognized FMDV strains of wide diversity of all seven serotypes but weaker reactions were often evident with those of type SAT 2, several viruses of which were not detected. Reactions with the viruses of swine vesicular disease and vesicular stomatitis that produce clinically indistinguishable syndromes in pigs and cattle, did not occur. The test procedure was simple and rapid, and typically provided a result within 1-10min of sample addition. Simple homogenizers that could be used in field conditions for preparing epithelial suspensions were demonstrated to be effective for LFD application. These data illustrate the potential for the LFD to be used next to the animal in the pen-side diagnosis of FMD and for providing rapid and objective support to veterinarians in their clinical judgment of the disease.

The serological diagnosis of canine visceral leishmaniasis (CVL) remains problematic because there areno reliable commercially available tests. Most laboratories use domestically prepared tests such as the enzyme-linked immunosorbent assay (ELISA) or the indirect immunofluorescent antibody test (IFAT). We evaluated rapid immunochromatographic (RICH) test kits for the diagnosis of CVL. The tests were assembled with either Leishmania chagasi recombinant antigens K39 or K26 and with either gold-labelled Staphylococcus aureus protein A or Streptococcus pyogenes protein G. Fifty sera from dogs with CVL, 14 sera from dogs with Chagas disease, and 50 sera from normal healthy dogs were tested. The results show that the RICH test using recombinant antigen K39 has a sensitivity of 96% and 100% specificity for the diagnosis of CVL. No significant differences were observed in the tests assembled with either protein A or protein G. The RICH tests using recombinant antigen K26 were equally specific but less sensitive than those using K39. However, the 2 antigens complemented each other and increased the overall sensitivity of the test. Because of its simplicity and performance the RICH test is a quick and reliable alternative for the diagnosis of CVL either in conventional laboratories or for remote areas where laboratories are not readily accessible for conventional assays.

Foot-and-mouth disease (FMD) is the most contagious animal virus disease of cloven-hoofed livestock and requires reliable and accurate diagnosis for the implementation of measures to control effectively its spread. Routine diagnosis of FMD is carried out at the OIE/FAO World Reference Laboratory for Foot-and-Mouth Disease (WRL for FMD), Pirbright by the combined use of ELISA and virus isolation in cell culture supplemented by reverse transcription polymerase chain reaction (RT-PCR) methods. These techniques require skilled personnel and dedicated laboratory facilities which are expensive. The development of a rapid and simple test for the detection of FMD virus antigen using Clearview chromatographic strip test technology for field application is described. This device detected FMD viral antigen in nasal swabs, epithelial suspensions and probangs from clinical samples submitted from the field, from animals infected experimentally and in supernatant fluids resulting from their passage in cell culture. The test system was more sensitive than ELISA for the diagnosis of all seven serotypes of FMD virus in the epithelial suspensions and nasal swabs and had equivalent sensitivity to the ELISA for the detection of contemporary virus strains in cell culture supernatant fluids. The study demonstrated the potential for this device to confirm a clinical diagnosis at the site of a suspected FMD outbreak, thereby offering the possibility of implementing control procedures more rapidly. Such pen-side diagnosis would have particular benefits in FMD emergencies, relevance to FMD control programmes which operate in endemic regions of the world such as South East Asia and for increasing disease awareness in other areas where efforts to control disease may be difficult. In each circumstance the availability of a pen-side device for diagnosis would reduce the necessity for sending routine diagnostic samples to an FMD laboratory and thereby reduce the delay in diagnosis, which can in some areas be considerable.

Rinderpest is a contagious viral disease of cloven-hoofed domestic and wild animals. Eradication of the virus following outbreaks depends on rapid and accurate diagnosis of infection and the implementation of control measures. Reporting and confirmatory diagnosis precede the implementation of control measures. A number of techniques have been used for diagnosis such as agar gel immunodiffusion, enzyme-linked immunosorbent assay (ELISA), molecular biological techniques such as polymerase chain reaction (PCR) and virus isolation in tissue culture. Many of these methods are both time consuming and require skilled personnel. The development of a rapid pen-side test for the detection of rinderpest virus (RPV) antigen in lachrymal fluid of cattle is described using the Clearview chromatographic strip test technology (Unipath, Bedford). Optimum conditions for binding monoclonal antibody to nitrocellulose and latex microspheres were determined and a prototype device was developed. The device detected viral antigen in lachrymal fluids from experimentally and naturally infected cattle and showed no cross-reactivity with other related viruses. A field trial was carried out at the Landhi Cattle Colony (LCC), Pakistan, to assess the performance of the rinderpest test under field conditions. Ninety-seven animals, some of which were showing various clinical signs, at LCC and neighbouring colonies were sampled and tested at the pen-side by Clearview and later by immunocapture ELISA (IC-ELISA) at IAH, Pirbright. Nineteen animals were positive by Clearview and/or IC-ELISA. Seventeen out of 19 rinderpest positive animals were positive by Clearview and 15 out of 19 were positive by IC-ELISA. Reverse transcription polymerase chain reaction (RT-PCR) confirmed the 19 animals to be rinderpest positive. This simple, rapid, specific test allows for the first time, accurate pen-side diagnosis of rinderpest.