Comparison of quantitative reverse transcription-PCR to viral culture for assessment of respiratory syncytial virus shedding.
Respiratory syncytial virus (RSV) has recently been recognized as a serious pathogen in elderly and immunocompromised adults. Diagnosis of acute infection in adults is often difficult due to the insensitivity of viral culture, and reverse transcription-PCR (RT-PCR) is a more sensitive alternative. The relationship of quantitative RT-PCR to viable virus has never been studied for RSV. Therefore, we compared a quantitative real-time RT-PCR with viral culture to assess viral load in adult volunteers challenged with the RSV A2 strain. Twelve of 13 volunteers were infected, and there was a high correlation (r = 0.84) between quantitative RT-PCR and viral titer by cell culture. However, RT-PCR was more sensitive, with 73 of 169 (43%) samples positive compared to 58 (34%) samples positive by culture. The correlation between the two tests was highest early in the course of viral shedding (r = 0.91, days 0 to 6), whereas during days 7 to 13, there was more variability (r = 0.70). All subjects were culture negative by day 11, whereas one subject remained RT-PCR positive on day 12. All subjects were RT-PCR negative at day 28 postinfection. Quantitative RT-PCR has an excellent correlation with viral titers, as measured by culture, and should be a useful tool for future studies addressing viral load and disease pathogenesis.
Falsey
Ann R
AR
Department of Medicine. Infectious Disease Unit, Rochester General Hospital, University of Rochester School of Medicine and Dentistry, Rochester, New York 14621, USA. ann.falsey@viahealth.org
Formica
Maria A
MA
Treanor
John J
JJ
Walsh
Edward E
EE
D000328:Adult; D000914:Antibodies, Viral / Q000032:analysis; D006801:Humans; D007071:Immunoglobulin A, Secretory / Q000032:analysis; D008875:Middle Aged; D009297:Nasal Mucosa / Q000821:virology; D012367:RNA, Viral / Q000032:analysis; D018113:Respiratory Syncytial Virus, Human / Q000235:genetics / Q000302:isolation & purification*; D020133:Reverse Transcriptase Polymerase Chain Reaction / Q000379:methods*; D019562:Viral Load; D014776:Virus Cultivation; D017201:Virus Shedding
D000914:Antibodies, Viral; D007071:Immunoglobulin A, Secretory; D012367:RNA, Viral