Rapid test for detection of IgM and IgG antibodies to S. typhi in serum/plasma/whole blood DEVICE

Typhoid fever is a systemic prolonged febrile illness caused by a bacteria Salmonella typhi. The disease is transmitted through ingestion of food or water contaminated with faeces or urine of infected persons. Acute typhoid fever is characterized by prolonged fever, disturbances of bowel functions (constipation or diarrhoea), headache, malaise and anorexia. Cough is common in the early stage of illness. Chronic carrier is determined when excretion of S.typhi in stools or urine lasts for longer than one year after onset of acute typhoid fever. Accurate diagnosis of typhoid fever at an early stage is not only important for etiological diagnosis but to identify and treat the potential carriers and prevent acute typhoid fever outbreaks. Specific agglutinins appear during the course of most of the attacks during the second week of infection. Detectable levels of IgM antibodies against S.typhi appear and persists for four months, IgG antibodies are detected thereafter and remain in blood for two years. The detection of IgM reveals acute typhoid in the early phase of infection, while the detection of both IgG and IgM suggests acute typhoid in the middle phase of infection. In areas of high endemicity, where the rate of typhoid transmission is high, the detection of specific IgG increases. In the conventional Widal test the interpretation of results is done against a baseline titre in the same geographical area since titres of diagnostic significance differ in endemic or non-endemic areas. A paired sera with a fourfold rise in titer is needed for a meaningful result. TM The limitations of the traditional methods have prompted novel tests to be developed. qualitatively detects and differentiates between IgM and IgG class of antibodies specific to S. typhi in human serum/plasma or whole blood specimens.