The use of serum spotted onto filter paper for diagnosing and monitoring Chikungunya virus infection.

Background The recent emergence of Chikungunya Virus (CHIKV) in the Americas constitutes a major public health problem on this continent, where the mosquito vector is widespread. The rapid diagnosis of suspected cases is essential for the monitoring and control of this ongoing outbreak. However, this requires reliable tools that are difficult to establish in areas without specialized laboratories. Objectives The aim was to evaluate the performances of serum samples spotted onto filter paper for molecular and serological diagnosis of Chikungunya infection. Study design Analyses were performed from frozen sera and serum spotted onto filter paper provided from 121 Chikungunya suspected cases collected at a biological laboratory on Saint-Martin Island. Results This approach performed well in comparisons with standard methods, with a sensitivity of 100% and a specificity of 93.6% for the combined technical approaches (RT-PCR and serological results). Comparisons of serum samples spotted onto filter paper and frozen samples showed a concordance rate of 94.8% in molecular tests and 98.2% in serological tests. Conclusions This simple sampling technique could overcome the problems of the lack of efficient CHIKV diagnosis tools in remote regions, providing good results regardless of the molecular or serological approach used. This simple filter paper-based method can be used to diagnose both chikungunya and dengue infections, as previously demonstrated following transport at ambient temperature to specialized laboratories. Given the set-up costs and high performance of this method, it could be recommended for the monitoring and control of Chikungunya virus expansion in the Americas and in other affected regions. [ABSTRACT FROM AUTHOR]