Times to key events in Zika virus infection and implications for blood donation: a systematic review.
OBJECTIVE
To estimate the timing of key events in the natural history of Zika virus infection.


METHODS
In February 2016, we searched PubMed, Scopus and the Web of Science for publications containing the termZika. By pooling data, we estimated the incubation period, the time to seroconversion and the duration of viral shedding. We estimated the risk of Zika virus contaminated blood donations.


RESULTS
We identified 20 articles on 25 patients with Zika virus infection. The median incubation period for the infection was estimated to be 5.9 days (95% credible interval, CrI: 4.4-7.6), with 95% of people who developed symptoms doing so within 11.2 days (95% CrI: 7.6-18.0) after infection. On average, seroconversion occurred 9.1 days (95% CrI: 7.0-11.6) after infection. The virus was detectable in blood for 9.9 days (95% CrI: 6.9-21.4) on average. Without screening, the estimated risk that a blood donation would come from an infected individual increased by approximately 1 in 10 000 for every 1 per 100 000 person-days increase in the incidence of Zika virus infection. Symptom-based screening may reduce this rate by 7% (relative risk, RR: 0.93; 95% CrI: 0.89-0.99) and antibody screening, by 29% (RR: 0.71; 95% CrI: 0.28-0.88).


CONCLUSIONS
Neither symptom- nor antibody-based screening for Zika virus infection substantially reduced the risk that blood donations would be contaminated by the virus. Polymerase chain reaction testing should be considered for identifying blood safe for use in pregnant women in high-incidence areas.
Johns Hopkins Bloomberg School of Public Health, 615 North Wolfe Street, Baltimore, Maryland, MD 21205, United States of America (USA).
Justin
J
Lessler
Johns Hopkins Bloomberg School of Public Health, 615 North Wolfe Street, Baltimore, Maryland, MD 21205, United States of America (USA).
Cassandra T
CT
Ott
Johns Hopkins Bloomberg School of Public Health, 615 North Wolfe Street, Baltimore, Maryland, MD 21205, United States of America (USA).
Andrea C
AC
Carcelen
Johns Hopkins Bloomberg School of Public Health, 615 North Wolfe Street, Baltimore, Maryland, MD 21205, United States of America (USA).
Jacob M
JM
Konikoff
Johns Hopkins Bloomberg School of Public Health, 615 North Wolfe Street, Baltimore, Maryland, MD 21205, United States of America (USA).
Joe
J
Williamson
Johns Hopkins Bloomberg School of Public Health, 615 North Wolfe Street, Baltimore, Maryland, MD 21205, United States of America (USA).
Qifang
Q
Bi
Johns Hopkins University School of Medicine, Baltimore, USA .
Lauren M
LM
Kucirka
University of Florida, Gainesville, USA .
Derek At
DA
Cummings
School of Public Health and Health Sciences, University of Massachusetts Amherst, Amherst, USA .
Nicholas G
NG
Reich
Johns Hopkins Bloomberg School of Public Health, 615 North Wolfe Street, Baltimore, Maryland, MD 21205, United States of America (USA).
Lelia H
LH
Chaisson
D000328:Adult; D001782:Blood Donors; D005260:Female; D006801:Humans; D055256:Infectious Disease Incubation Period; D008297:Male; D008875:Middle Aged; D000069078:Seroconversion; D000071244:Zika Virus / Q000302:isolation & purification*