S. typhi H antigen O antigen 15 minutes Shelf Life wide range High level human serum operator error immediate action skilled personnel paratyphi serovars One step procedure laboratory equipment medical professionals antibody detection test preparation Test result 2-30°C Typhoid Test kit lateral flow immunoassay IgM anti-Salmonella typhi reproducibility Test kits sensitivity Differentiates 24 months Storage Temperature noninvasive diagnostic method Typhoid IgG/IgM Combo Rapid Test InfectiousDiseaseTesting #DiagnosticTools