Typhidot
Typhidot is based on the presence of specific IgM and IgG antibodies to a specific 50Kd OMP antigen. This test is carried out on a cellulose nitrate membrane where a specific S. typhi outer membrane protein is attached as fixed test lines. It separately identifies IgM and IgG antibodies. IgM shows recent infection; IgG signifies remote infection. The sample pad of this kit contains colloidal gold-anti-human IgG or gold-anti-human IgM. If the sample contains IgG and IgM antibodies against those antigens, they will react and turn red. The typhidot test becomes positive within 2–3 days of infection. Two colored bands indicate a positive test. A single control band indicates a negative test. A single first fixed line or no band at all indicates an invalid test. Typhidots biggest limitation is that it is not quantitative, just positive or negative. Tubex test
The Tubex test contains two types of particles: brown magnetic particles coated with antigen and blue indicator particles coated with O9 antibody. During the test, if antibodies are present in the serum, they will attach to the brown magnetic particles and settle at the base, while the blue indicator particles remain in the solution, producing a blue color, which means the test is positive.If the serum does not have an antibody in it, the blue particles attach to the brown particles and settle at the bottom, producing a colorless solution, which means the test is negative. Prevention
Sanitation and hygiene are important to prevent typhoid.
At the time of Mallons tenure as a personal cook for upper-class families, New York City reported 3,000 to 4,500 cases of typhoid fever annually. In the summer of 1906 two daughters of a wealthy family and maids working in their home became ill with typhoid fever. After investigating their home water sources and ruling out water contamination, the family hired civil engineer George Soper to conduct an investigation of the possible source of typhoid fever in the home. Soper described himself as an "epidemic fighter". His investigation ruled out many sources of food, and led him to question if the cook the family hired just prior to their household outbreak, Mallon, was the source. Since she had already left and begun employment elsewhere, he proceeded to track her down in order to obtain a stool sample. When he was able to finally meet Mallon in person he described her by saying "Mary had a good figure and might have been called athletic had she not been a little too heavy." In recounts of Sopers pursuit of Mallon, his only remorse appears to be that he was not given enough credit for his relentless pursuit and publication of her personal identifying information, stating that the media "rob[s] me of whatever credit belongs to the discovery of the first typhoid fever carrier to be found in America."