An indirect immunofluorescence assay to detect antibodies against St. Louis Encephalitis virus

• Main Authors: SPINSANTI Lorena, RE Viviana, AGUILAR Javier, CONTIGIANI Marta
• Format: Article in Journal/Newspaper
• Language: English
• Published: Universidade de São Paulo (USP) 2001
• Subjects: Indirect immunofluorescence assay; Neutralization test; St. Louis Encephalitis virus; Arctic medicine. Tropical medicine; RC955-962; Infectious and parasitic diseases; RC109-216; Arctic; St. Louis
• Online Access: https://doaj.org/article/30e3aa209d5e45f7a4b1fb7979ba9fef

An in house indirect immmunofluorescence assay ( IFA ) in relation to neutralization (NT) reference test, was assessed as a fast and cheap method to carry out serological surveys for St. Louis Encephalitis virus (SLE). Sera obtained from 213 blood donors were analyzed by both tests. The prevalence of seropositivity obtained with IFA was lower than (30.98%) that observed on NT (41.78%). The relative specificity rate of IFA was 96.77% whereas its relative sensitivity rate was 69.66%. Kappa index showed a good correlation between both tests. The results indicate that neutralization assay is still the serological test with the highest sensitivity and specificity relative rates for detecting antibodies against SLE virus. Nevertheless, the IFA could be useful as an alternative test in order to learn the circulation of the Flavivirus genus in a certain area.