TY - JOUR
T1 - Determinants of Transmission Risk during the Late Stage of the West African Ebola Epidemic
AU - Robert, Alexis
AU - John Edmunds, W.
AU - Watson, Conall H.
AU - Henao-Restrepo, Ana Maria
AU - Gsell, Pierre Stéphane
AU - Williamson, Elizabeth
AU - Longini, Ira M.
AU - Sakoba, Keïta
AU - Kucharski, Adam J.
AU - Touré, Alhassane
AU - Nadlaou, Sévérine Danmadji
AU - Diallo, Boubacar
AU - Barry, Mamamdou Saidou
AU - Fofana, Thierno Oumar
AU - Camara, Louceny
AU - Kaba, Ibrahima Lansana
AU - Sylla, Lansana
AU - Diaby, Mohamed Lamine
AU - Soumah, Ousmane
AU - Diallo, Abdourahime
AU - Niare, Amadou
AU - Diallo, Abdourahmane
AU - Eggo, Rosalind M.
N1 - Publisher Copyright:
© 2019 The Author(s) 2019. Published by Oxford University Press on behalf of the Johns Hopkins Bloomberg School of Public Health.
PY - 2019/7/1
Y1 - 2019/7/1
N2 - Understanding risk factors for Ebola transmission is key for effective prediction and design of interventions. We used data on 860 cases in 129 chains of transmission from the latter half of the 2013-2016 Ebola epidemic in Guinea. Using negative binomial regression, we determined characteristics associated with the number of secondary cases resulting from each infected individual. We found that attending an Ebola treatment unit was associated with a 38% decrease in secondary cases (incidence rate ratio (IRR) = 0.62, 95% confidence interval (CI): 0.38, 0.99) among individuals that did not survive. Unsafe burial was associated with a higher number of secondary cases (IRR = 1.82, 95% CI: 1.10, 3.02). The average number of secondary cases was higher for the first generation of a transmission chain (mean = 1.77) compared with subsequent generations (mean = 0.70). Children were least likely to transmit (IRR = 0.35, 95% CI: 0.21, 0.57) compared with adults, whereas older adults were associated with higher numbers of secondary cases. Men were less likely to transmit than women (IRR = 0.71, 95% CI: 0.55, 0.93). This detailed surveillance data set provided an invaluable insight into transmission routes and risks. Our analysis highlights the key role that age, receiving treatment, and safe burial played in the spread of EVD.
AB - Understanding risk factors for Ebola transmission is key for effective prediction and design of interventions. We used data on 860 cases in 129 chains of transmission from the latter half of the 2013-2016 Ebola epidemic in Guinea. Using negative binomial regression, we determined characteristics associated with the number of secondary cases resulting from each infected individual. We found that attending an Ebola treatment unit was associated with a 38% decrease in secondary cases (incidence rate ratio (IRR) = 0.62, 95% confidence interval (CI): 0.38, 0.99) among individuals that did not survive. Unsafe burial was associated with a higher number of secondary cases (IRR = 1.82, 95% CI: 1.10, 3.02). The average number of secondary cases was higher for the first generation of a transmission chain (mean = 1.77) compared with subsequent generations (mean = 0.70). Children were least likely to transmit (IRR = 0.35, 95% CI: 0.21, 0.57) compared with adults, whereas older adults were associated with higher numbers of secondary cases. Men were less likely to transmit than women (IRR = 0.71, 95% CI: 0.55, 0.93). This detailed surveillance data set provided an invaluable insight into transmission routes and risks. Our analysis highlights the key role that age, receiving treatment, and safe burial played in the spread of EVD.
KW - Ebola
KW - Guinea
KW - multiple imputation
KW - regression analysis
KW - risk factors
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U2 - 10.1093/aje/kwz090
DO - 10.1093/aje/kwz090
M3 - Article
C2 - 30941398
AN - SCOPUS:85069238357
SN - 0002-9262
VL - 188
SP - 1319
EP - 1327
JO - American Journal of Epidemiology
JF - American Journal of Epidemiology
IS - 7
ER -
