The potential for sexual transmission to compromise control of Ebola virus outbreaks.
Recent evidence suggests that sexual contact may give rise to transmission of Ebola virus long after infection has been cleared from blood. We develop a simple mathematical model that incorporates contact transmission and sexual transmission parametrized from data relating to the 2013-2015 West African Ebola epidemic. The model explores scenarios where contact transmission is reduced following infection events, capturing behaviour change, and quantifies how these actions reducing transmission may be compromised by sexual transmission in terms of increasing likelihood, size and duration of outbreaks. We characterize the extent to which sexual transmission operates in terms of the probability of initial infection resolving to sexual infectiousness and the sexual transmission rate, and relate these parameters to the overall case burden. We find that sexual transmission can have large effects on epidemic dynamics (increasing attack ratios from 25% in scenarios without sexual transmission but with contact-transmission-reducing behaviour, up to 80% in equivalent scenarios with sexual transmission).
Odum School of Ecology, University of Georgia, Athens, GA 30602, USA.
John E
0000-0003-4319-6851
JE
Vinson
Odum School of Ecology, University of Georgia, Athens, GA 30602, USA.
John M
0000-0003-4646-1235
JM
Drake
Odum School of Ecology, University of Georgia, Athens, GA 30602, USA Department of Infectious Diseases, College of Veterinary Medicine, University of Georgia, Athens, GA 30602, USA.
Pejman
0000-0002-7221-3801
P
Rohani
Odum School of Ecology, University of Georgia, Athens, GA 30602, USA Department of Infectious Diseases, College of Veterinary Medicine, University of Georgia, Athens, GA 30602, USA awpark@uga.edu.
Andrew W
0000-0003-4080-7274
AW
Park
D000354:Africa, Western / Q000453:epidemiology; D004196:Disease Outbreaks / Q000517:prevention & control*; D029043:Ebolavirus / Q000502:physiology; D005260:Female; D019142:Hemorrhagic Fever, Ebola / Q000453:epidemiology* / Q000517:prevention & control / Q000635:transmission*; D006801:Humans; D016013:Likelihood Functions; D008297:Male; D008962:Models, Theoretical; D012661:Semen / Q000821:virology; D012725:Sexual Behavior; D015229:Sexually Transmitted Diseases, Viral / Q000453:epidemiology* / Q000517:prevention & control / Q000635:transmission
Ebola virus; epidemic; mathematical model; population dynamics; sexual transmission