Autor(es): Prince Harry E, Seaton Brent L, Matud Jose L, Batterman Hollis J

Resumo: Since first reported in the Americas in December 2013, chikungunya virus (CHIKV) infections have been documented in travelers returning from the Caribbean, with many cases identified by CHIKV antibody -/or RNA testing at our laboratory. We used our large data set to characterize the relationship between antibody titers - RNA detection - to estimate IgM persistence. CHIKV RNA was measured by nucleic acid amplification - CHIKV IgG/IgM by indirect immunofluorescence. Of the 1,306 samples submitted for RNA testing in January through September 2014, 393 (30%) were positive; for 166 RNA-positive samples, CHIKV antibody testing was also ordered, - 84% were antibody negative. Of the 6,971 sera submitted for antibody testing in January through September 2014, 1,811 (26%) were IgM positive; 1,461 IgM positives (81%) were also IgG positive. The relationship between the CHIKV antibody titers - RNA detection was evaluated using 376 IgM-positive samples (138 with RNA testing ordered - 238 deidentified - tested for RNA). RNA detection showed no significant association with the IgM titer but was inversely related to the IgG titer; 63% of the IgG negative sera were RNA positive, compared to 36% of sera with low IgG titers (1:10 to 1:80) - 16% with IgG titers of ?1:160. Using second-sample results from 62 seroconverters, we estimated that CHIKV IgM persists for 110 days (95% confidence interval, 78 to 150 days) after the initial antibody-negative sample. These findings indicate that (i) RNA detection is more sensitive than antibody detection early in CHIKV infection, (ii) in the absence of RNA results, the IgG titer of the IgM-positive samples may be a useful surrogate for viremia, - (iii) CHIKV IgM persists for approximately 4 months after symptom onset.

Imprenta: Clinical and Vaccine Immunology, v. 22, n. 3, p. 291-297, 2015

Identificador do objeto digital: 10.1128/CVI.00720-14

Descritores: Chikungunya virus - Pathogenesis ; Chikungunya virus - Proteins ; Chikungunya virus - RNA ; Chikungunya virus - Antibodies ; Chikungunya virus - Inflammation ; Chikungunya virus - Viral infections ; Chikungunya virus - Real Time PCR ; Chikungunya virus - RT-PCR ; Chikungunya Virus - Virus ; Chikungunya virus - Vaccine ; Chikungunya virus - Chikungunya fever ; Chikungunya virus - Epidemiology ; Chikungunya virus - Immunology ; Chikungunya virus - Public health

Data de publicação: 2015