The Rapid-VIDITEST Salmonella typhi Card is a one step coloured chromatographic immunoassay for the qualitative detection of Salmonella typhi in faecal samples in order to detect typhoid fever in persons.
Store as packaged in the sealed pouch either at refrigerated or room temperature (2-30°C/36-86°F). The test is stable through the expiration date printed on the sealed pouch. The test must remain in the sealed pouch until use. Do not freeze.
The detection limit is: S. typhi: 1x104 bacteria/mL.
Sensitivity and specificity
It was performed an evaluation using Salmonella typhi culture. The correlation between two assays, Salmonella and Rapid-VIDITEST Salmonella typhi Card was >99%. It was also evaluated 20 stool samples using both assays. The results showed a high sensitivity and specificity using Rapid-VIDITEST Salmonella typhi Card.
The antibodies used to elaborate this test recognise S. typhi epitopes found in stool of patients, as well as in preparations from the bacteria cultures in vitro.
This preliminary values has to be taken with precaution until more evaluation data will be available.
It was performed an evaluation to determine the cross reactivity of Rapid-VIDITEST Salmonella typhi Card. There is not cross reactivity with common intestinal pathogens, other organisms and substances occasionally present in faeces: H. pylori, Escherichia coli O157:H7, Listeria monocytogenes, Campylobacter.
Clinical syndromes in humans caused by infection with Salmonella enterica are divided into typhoid fever, caused by S. enterica serovars typhi and paratyphi, and a range of clinical syndromes, including diarrhoeal disease, caused by the non-typhoid Salmonellae (NTS) of which there are around 2,500 serovars. Typhoid fever is a human-restricted and highly adapted invasive systemic disease of adults and children that shows little association with immunosuppression. In contrast, NTS have a broad vertebrate host range and epidemiology that often involves food animals, at least in industrialised countries where it usually presents as gastroenteritis. Severe, invasive disease due to NTS is usually associated with the immunocompromised state common in HIV-infected adults. Invasive NTS disease is also common in young African children with co-morbidities such as severe anaemia, malnutrition and HIV infection.
Rapid-VIDITEST Salmonella tyhpi Card provides a rapid detection of Salmonella typhi directly from the faecal samples.