ABSTRACT
Ebola virus (EBOV) can persist in immunologically protected body sites in survivors of Ebola virus disease, creating the potential to initiate new chains of transmission. From the outbreak in West Africa during 2014-2016, we identified 13 possible events of viral persistence-derived transmission of EBOV (VPDTe) and applied predefined criteria to classify transmission events based on the strength of evidence for VPDTe and source and route of transmission. For 8 events, a recipient case was identified; possible source cases were identified for 5 of these 8. For 5 events, a recipient case or chain of transmission could not be confidently determined. Five events met our criteria for sexual transmission (male-to-female). One VPDTe event led to at least 4 generations of cases; transmission was limited after the other events. VPDTe has increased the importance of Ebola survivor services and sustained surveillance and response capacity in regions with previously widespread transmission.
Subject(s)
Disease Outbreaks , Ebolavirus , Hemorrhagic Fever, Ebola/epidemiology , Hemorrhagic Fever, Ebola/transmission , Survivors , Adolescent , Adult , Africa, Western/epidemiology , Ebolavirus/classification , Ebolavirus/genetics , Ebolavirus/isolation & purification , Female , Hemorrhagic Fever, Ebola/virology , Humans , Male , Middle Aged , Public Health Surveillance , Young AdultABSTRACT
BACKGROUND: Effective surveillance for infectious diseases is an essential component of public health. There are few studies estimating the cost-effectiveness of starting or improving disease surveillance. We present a cost-effectiveness analysis the Integrated Disease Surveillance and Response (IDSR) strategy in Africa. METHODOLOGY/PRINCIPAL FINDINGS: To assess the impact of the IDSR in Africa, we used pre- and post- IDSR meningococcal meningitis surveillance data from Burkina Faso (1996-2002 and 2003-2007). IDSR implementation was correlated with a median reduction of 2 weeks to peak of outbreaks (25(th) percentile 1 week; 75(th) percentile 4 weeks). IDSR was also correlated with a reduction of 43 meningitis cases per 100,000 (25(th)-40: 75(th)-129). Assuming the correlations between reductions in time to peak of outbreaks and cases are related, the cost-effectiveness of IDSR was $23 per case averted (25(th)-$30; 75(th)--cost saving), and $98 per meningitis-related death averted (25(th)-$140: 75(th)--cost saving). CONCLUSIONS/SIGNIFICANCE: We cannot absolutely claim that the measured differences were due to IDSR. We believe, however, that it is reasonable to claim that IDSR can improve the cost-effectiveness of public health surveillance.
