Potential Impact of Sexual Transmission on Ebola Virus Epidemiology: Sierra Leone as a Case Study.
BACKGROUND:Sexual transmission of Ebola virus disease (EVD) 6 months after onset of symptoms has been recently documented, and Ebola virus RNA has been detected in semen of survivors up to 9 months after onset of symptoms. As countries affected by the 2013-2015 epidemic in West Africa, by far the la...
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ftdoajarticles:oai:doaj.org/article:50cd131e1b0144f18e74ab23c9aa3aa1 2023-05-15T15:14:39+02:00 Potential Impact of Sexual Transmission on Ebola Virus Epidemiology: Sierra Leone as a Case Study. Jessica L Abbate Carmen Lia Murall Heinz Richner Christian L Althaus 2016-05-01T00:00:00Z https://doi.org/10.1371/journal.pntd.0004676 https://doaj.org/article/50cd131e1b0144f18e74ab23c9aa3aa1 EN eng Public Library of Science (PLoS) http://europepmc.org/articles/PMC4852896?pdf=render https://doaj.org/toc/1935-2727 https://doaj.org/toc/1935-2735 1935-2727 1935-2735 doi:10.1371/journal.pntd.0004676 https://doaj.org/article/50cd131e1b0144f18e74ab23c9aa3aa1 PLoS Neglected Tropical Diseases, Vol 10, Iss 5, p e0004676 (2016) Arctic medicine. Tropical medicine RC955-962 Public aspects of medicine RA1-1270 article 2016 ftdoajarticles https://doi.org/10.1371/journal.pntd.0004676 2023-01-08T01:24:30Z BACKGROUND:Sexual transmission of Ebola virus disease (EVD) 6 months after onset of symptoms has been recently documented, and Ebola virus RNA has been detected in semen of survivors up to 9 months after onset of symptoms. As countries affected by the 2013-2015 epidemic in West Africa, by far the largest to date, are declared free of Ebola virus disease (EVD), it remains unclear what threat is posed by rare sexual transmission events that could arise from survivors. METHODOLOGY/PRINCIPAL FINDINGS:We devised a compartmental mathematical model that includes sexual transmission from convalescent survivors: a SEICR (susceptible-exposed-infectious-convalescent-recovered) transmission model. We fitted the model to weekly incidence of EVD cases from the 2014-2015 epidemic in Sierra Leone. Sensitivity analyses and Monte Carlo simulations showed that a 0.1% per sex act transmission probability and a 3-month convalescent period (the two key unknown parameters of sexual transmission) create very few additional cases, but would extend the epidemic by 83 days [95% CI: 68-98 days] (p < 0.0001) on average. Strikingly, a 6-month convalescent period extended the average epidemic by 540 days (95% CI: 508-572 days), doubling the current length, despite an insignificant rise in the number of new cases generated. CONCLUSIONS/SIGNIFICANCE:Our results show that reductions in the per sex act transmission probability via abstinence and condom use should reduce the number of sporadic sexual transmission events, but will not significantly reduce the epidemic size and may only minimally shorten the length of time the public health community must maintain response preparedness. While the number of infectious survivors is expected to greatly decline over the coming months, our results show that transmission events may still be expected for quite some time as each event results in a new potential cluster of non-sexual transmission. Precise measurement of the convalescent period is thus important for planning ongoing surveillance efforts. Article in Journal/Newspaper Arctic Directory of Open Access Journals: DOAJ Articles Arctic PLOS Neglected Tropical Diseases 10 5 e0004676 |
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Directory of Open Access Journals: DOAJ Articles |
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English |
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Arctic medicine. Tropical medicine RC955-962 Public aspects of medicine RA1-1270 |
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Arctic medicine. Tropical medicine RC955-962 Public aspects of medicine RA1-1270 Jessica L Abbate Carmen Lia Murall Heinz Richner Christian L Althaus Potential Impact of Sexual Transmission on Ebola Virus Epidemiology: Sierra Leone as a Case Study. |
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Arctic medicine. Tropical medicine RC955-962 Public aspects of medicine RA1-1270 |
description |
BACKGROUND:Sexual transmission of Ebola virus disease (EVD) 6 months after onset of symptoms has been recently documented, and Ebola virus RNA has been detected in semen of survivors up to 9 months after onset of symptoms. As countries affected by the 2013-2015 epidemic in West Africa, by far the largest to date, are declared free of Ebola virus disease (EVD), it remains unclear what threat is posed by rare sexual transmission events that could arise from survivors. METHODOLOGY/PRINCIPAL FINDINGS:We devised a compartmental mathematical model that includes sexual transmission from convalescent survivors: a SEICR (susceptible-exposed-infectious-convalescent-recovered) transmission model. We fitted the model to weekly incidence of EVD cases from the 2014-2015 epidemic in Sierra Leone. Sensitivity analyses and Monte Carlo simulations showed that a 0.1% per sex act transmission probability and a 3-month convalescent period (the two key unknown parameters of sexual transmission) create very few additional cases, but would extend the epidemic by 83 days [95% CI: 68-98 days] (p < 0.0001) on average. Strikingly, a 6-month convalescent period extended the average epidemic by 540 days (95% CI: 508-572 days), doubling the current length, despite an insignificant rise in the number of new cases generated. CONCLUSIONS/SIGNIFICANCE:Our results show that reductions in the per sex act transmission probability via abstinence and condom use should reduce the number of sporadic sexual transmission events, but will not significantly reduce the epidemic size and may only minimally shorten the length of time the public health community must maintain response preparedness. While the number of infectious survivors is expected to greatly decline over the coming months, our results show that transmission events may still be expected for quite some time as each event results in a new potential cluster of non-sexual transmission. Precise measurement of the convalescent period is thus important for planning ongoing surveillance efforts. |
format |
Article in Journal/Newspaper |
author |
Jessica L Abbate Carmen Lia Murall Heinz Richner Christian L Althaus |
author_facet |
Jessica L Abbate Carmen Lia Murall Heinz Richner Christian L Althaus |
author_sort |
Jessica L Abbate |
title |
Potential Impact of Sexual Transmission on Ebola Virus Epidemiology: Sierra Leone as a Case Study. |
title_short |
Potential Impact of Sexual Transmission on Ebola Virus Epidemiology: Sierra Leone as a Case Study. |
title_full |
Potential Impact of Sexual Transmission on Ebola Virus Epidemiology: Sierra Leone as a Case Study. |
title_fullStr |
Potential Impact of Sexual Transmission on Ebola Virus Epidemiology: Sierra Leone as a Case Study. |
title_full_unstemmed |
Potential Impact of Sexual Transmission on Ebola Virus Epidemiology: Sierra Leone as a Case Study. |
title_sort |
potential impact of sexual transmission on ebola virus epidemiology: sierra leone as a case study. |
publisher |
Public Library of Science (PLoS) |
publishDate |
2016 |
url |
https://doi.org/10.1371/journal.pntd.0004676 https://doaj.org/article/50cd131e1b0144f18e74ab23c9aa3aa1 |
geographic |
Arctic |
geographic_facet |
Arctic |
genre |
Arctic |
genre_facet |
Arctic |
op_source |
PLoS Neglected Tropical Diseases, Vol 10, Iss 5, p e0004676 (2016) |
op_relation |
http://europepmc.org/articles/PMC4852896?pdf=render https://doaj.org/toc/1935-2727 https://doaj.org/toc/1935-2735 1935-2727 1935-2735 doi:10.1371/journal.pntd.0004676 https://doaj.org/article/50cd131e1b0144f18e74ab23c9aa3aa1 |
op_doi |
https://doi.org/10.1371/journal.pntd.0004676 |
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PLOS Neglected Tropical Diseases |
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10 |
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e0004676 |
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