The authors were interested in the frequency and duration of detectable Zika virus (ZIKV) RNA in body fluids and so prospectively assessed newly infected patients in Puerto Rico. Samples were obtained from 150 patients (including 55 men) in whom ZIKV RNA had been detected by RT-PCR in urine or blood. Serum, urine, saliva, semen and vaginal secretions were collected weekly for the first month and then at 2, 4 and 6 months. All of the specimens were tested by RT-PCR and the serum also for anti-ZIKV IgM. The authors found that the median and 95th percentiles time to loss of ZIKV RNA were 14 days and 54 days, respectively, in serum; 8 days and 39 days in urine; and 34 days and 81 days in semen. Few of the patients had detectable ZIKV RNA in either their saliva or vaginal secretions. Therefore ZIKV RNA can take up to 54 days to clear from serum and 81 days from semen.
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