TY - JOUR
T1 - Estimate of the reproduction number of the 2015 Zika virus outbreak in Barranquilla, Colombia, and estimation of the relative role of sexual transmission
AU - Towers, Sherry
AU - Brauer, Fred
AU - Castillo-Chavez, Carlos
AU - Falconar, Andrew K I
AU - Mubayi, Anuj
AU - Romero-Vivas, Claudia M E
N1 - Publisher Copyright:
© 2016 The Authors
PY - 2016/12/1
Y1 - 2016/12/1
N2 - Background In 2015, the Zika arbovirus (ZIKV) began circulating in the Americas, rapidly expanding its global geographic range in explosive outbreaks. Unusual among mosquito-borne diseases, ZIKV has been shown to also be sexually transmitted, although sustained autochthonous transmission due to sexual transmission alone has not been observed, indicating the reproduction number (R0) for sexual transmission alone is less than 1. Critical to the assessment of outbreak risk, estimation of the potential attack rates, and assessment of control measures, are estimates of the basic reproduction number, R0. Methods We estimated the R0 of the 2015 ZIKV outbreak in Barranquilla, Colombia, through an analysis of the exponential rise in clinically identified ZIKV cases (n = 359 to the end of November, 2015). Findings The rate of exponential rise in cases was ρ = 0.076 days−1, with 95% CI [0.066,0.087] days−1. We used a vector-borne disease model with additional direct transmission to estimate the R0; assuming the R0 of sexual transmission alone is less than 1, we estimated the total R0 = 3.8 [2.4,5.6], and that the fraction of cases due to sexual transmission was 0.23 [0.01,0.47] with 95% confidence. Interpretation This is among the first estimates of R0 for a ZIKV outbreak in the Americas, and also among the first quantifications of the relative impact of sexual transmission.
AB - Background In 2015, the Zika arbovirus (ZIKV) began circulating in the Americas, rapidly expanding its global geographic range in explosive outbreaks. Unusual among mosquito-borne diseases, ZIKV has been shown to also be sexually transmitted, although sustained autochthonous transmission due to sexual transmission alone has not been observed, indicating the reproduction number (R0) for sexual transmission alone is less than 1. Critical to the assessment of outbreak risk, estimation of the potential attack rates, and assessment of control measures, are estimates of the basic reproduction number, R0. Methods We estimated the R0 of the 2015 ZIKV outbreak in Barranquilla, Colombia, through an analysis of the exponential rise in clinically identified ZIKV cases (n = 359 to the end of November, 2015). Findings The rate of exponential rise in cases was ρ = 0.076 days−1, with 95% CI [0.066,0.087] days−1. We used a vector-borne disease model with additional direct transmission to estimate the R0; assuming the R0 of sexual transmission alone is less than 1, we estimated the total R0 = 3.8 [2.4,5.6], and that the fraction of cases due to sexual transmission was 0.23 [0.01,0.47] with 95% confidence. Interpretation This is among the first estimates of R0 for a ZIKV outbreak in the Americas, and also among the first quantifications of the relative impact of sexual transmission.
KW - Arboviruses
KW - Basic reproduction number
KW - Mathematical model
KW - Sexually transmitted infections
KW - Zika virus
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U2 - 10.1016/j.epidem.2016.10.003
DO - 10.1016/j.epidem.2016.10.003
M3 - Article
C2 - 27846442
AN - SCOPUS:84999040137
SN - 1755-4365
VL - 17
SP - 50
EP - 55
JO - Epidemics
JF - Epidemics
ER -