Journal Article > LetterFull Text
Nature. 2015 June 17; Volume 524 (Issue 7563); 97-101.; DOI:10.1038/nature14594
Carroll MW, Matthews DA, Hiscox JA, Elmore MJ, Pollakis G, et al.
Nature. 2015 June 17; Volume 524 (Issue 7563); 97-101.; DOI:10.1038/nature14594
West Africa is currently witnessing the most extensive Ebola virus (EBOV) outbreak so far recorded. Until now, there have been 27,013 reported cases and 11,134 deaths. The origin of the virus is thought to have been a zoonotic transmission from a bat to a twoyear-old boy in December 2013 (ref. 2). From this index case the virus was spread by human-to-human contact throughout Guinea, Sierra Leone and Liberia. However, the origin of the particular virus in each country and time of transmission is not known and currently relies on epidemiological analysis, which may be unreliable owing to the difficulties of obtaining patient information. Here we trace the genetic evolution of EBOV in the current outbreak that has resulted in multiple lineages. Deep sequencing of 179 patient samples processed by the European Mobile Laboratory, the first diagnostics unit to be deployed to the epicentre of the outbreak in Guinea, reveals an epidemiological and evolutionary history of the epidemic from March 2014 to January 2015. Analysis of EBOV genome evolution has also benefited from a similar sequencing effort of patient samples from Sierra Leone. Our results confirm that the EBOV from Guinea moved into Sierra Leone, most likely in April or early May. The viruses of the Guinea/Sierra Leone lineage mixed around June/July 2014. Viral sequences covering August, September and October 2014 indicate that this lineage evolved independently within Guinea. These data can be used in conjunction with epidemiological information to test retrospectively the effectiveness of control measures, and provides an unprecedented window into the evolution of an ongoing viral haemorrhagic fever outbreak.
Journal Article > Short ReportFull Text
Morbidity and Mortality Weekly Report. 2014 November 14; Volume 63; 1067-71.
Sharma A, Heijenberg N, Peter C, Bolongei J, Reeder B, et al.
Morbidity and Mortality Weekly Report. 2014 November 14; Volume 63; 1067-71.
WHAT IS ALREADY KNOWN ABOUT THIS TOPIC?
Lofa County in Liberia has one of the highest numbers of reported cases of Ebola virus disease (Ebola) in West Africa. Government health offices, nongovernmental organizations, and technical agencies coordinated response activities to reduce transmission of Ebola in Lofa County. The intensity and thoroughness of activities increased in response to the resurgence of Ebola in early June.
WHAT IS ADDED BY THIS REPORT?
Trends in new reported cases, admissions to the dedicated Ebola treatment unit in the town of Foya, and test results of community decedents evaluated for Ebola virus suggest transmission of Ebola virus decreased in Lofa County as early as August 17, 2014, following rapid scale-up of response activities after a resurgence of Ebola in early June.
WHAT ARE THE IMPLICATIONS FOR PUBLIC HEALTH PRACTICE?
A comprehensive Ebola response strategy developed with participation from the local community and rapidly scaled up following resurgence of Ebola might have reduced the spread of Ebola virus in Lofa County. The strategy implemented in Lofa County might serve as a model for reducing transmission of Ebola virus in other affected areas.
Lofa County in Liberia has one of the highest numbers of reported cases of Ebola virus disease (Ebola) in West Africa. Government health offices, nongovernmental organizations, and technical agencies coordinated response activities to reduce transmission of Ebola in Lofa County. The intensity and thoroughness of activities increased in response to the resurgence of Ebola in early June.
WHAT IS ADDED BY THIS REPORT?
Trends in new reported cases, admissions to the dedicated Ebola treatment unit in the town of Foya, and test results of community decedents evaluated for Ebola virus suggest transmission of Ebola virus decreased in Lofa County as early as August 17, 2014, following rapid scale-up of response activities after a resurgence of Ebola in early June.
WHAT ARE THE IMPLICATIONS FOR PUBLIC HEALTH PRACTICE?
A comprehensive Ebola response strategy developed with participation from the local community and rapidly scaled up following resurgence of Ebola might have reduced the spread of Ebola virus in Lofa County. The strategy implemented in Lofa County might serve as a model for reducing transmission of Ebola virus in other affected areas.
Journal Article > ResearchFull Text
Vaccine. 2020 June 1; Volume 38 (Issue 31); DOI:10.1016/j.vaccine.2020.04.066
Boum Y II, Juan-Giner A, Hitchings MD, Soumah A, Strecker T, et al.
Vaccine. 2020 June 1; Volume 38 (Issue 31); DOI:10.1016/j.vaccine.2020.04.066
Background
As part of a Phase III trial with the Ebola vaccine rVSVΔG-ZEBOV-GP in Guinea, we invited frontline workers (FLWs) to participate in a sub-study to provide additional information on the immunogenicity of the vaccine.
Methods
We conducted an open‐label, non‐randomized, single-arm immunogenicity evaluation of one dose of rVSVΔG-ZEBOV-GP among healthy FLWs in Guinea. FLWs who refused vaccination were offered to participate as a control group. We followed participants for 84 days with a subset followed-up for 180 days. The primary endpoint was immune response, as measured by ELISA for ZEBOV-glycoprotein–specific antibodies (ELISA-GP) at 28 days. We also conducted neutralization, whole virion ELISA and enzyme-linked immunospot (ELISPOT) assay for cellular response.
Results
A total of 1172 participants received one dose of vaccine and were followed-up for 84 days, among them 114 participants were followed-up for 180 days. Additionally, 99 participants were included in the control group and followed up for 180 days. Overall, 86.4% (95% CI 84.1–88.4) of vaccinated participants seroresponded at 28 days post-vaccination (ELISA- GP) with 65% of these seroresponding at 14 days post-vaccination. Among those who seroresponded at 28 days, 90.7% (95% CI 82.0–95.4) were still seropositive at 180 days. The proportion of seropositivity in the unvaccinated group was 0.0% (95% CI 0.0–3.8) at 28 days and 5.4% (95% CI 2.1–13.1) at 180 days post-vaccination. We found weak correlation between ELISA-GP and neutralization at baseline but significant pairwise correlation at 28 days post-vaccination. Among samples analysed for cellular response, only 1 (2.2%) exhibited responses towards the Zaire Ebola glycoprotein (Ebola GP ≥ 10) at baseline, 10 (13.5%) at day 28 post-vaccination and 27 (48.2%) at Day 180.
Conclusions
We found one dose of rVSVΔG-ZEBOV-GP to be highly immunogenic at 28- and 180-days post vaccination among frontline workers in Guinea. We also found a cellular response that increased with time.
As part of a Phase III trial with the Ebola vaccine rVSVΔG-ZEBOV-GP in Guinea, we invited frontline workers (FLWs) to participate in a sub-study to provide additional information on the immunogenicity of the vaccine.
Methods
We conducted an open‐label, non‐randomized, single-arm immunogenicity evaluation of one dose of rVSVΔG-ZEBOV-GP among healthy FLWs in Guinea. FLWs who refused vaccination were offered to participate as a control group. We followed participants for 84 days with a subset followed-up for 180 days. The primary endpoint was immune response, as measured by ELISA for ZEBOV-glycoprotein–specific antibodies (ELISA-GP) at 28 days. We also conducted neutralization, whole virion ELISA and enzyme-linked immunospot (ELISPOT) assay for cellular response.
Results
A total of 1172 participants received one dose of vaccine and were followed-up for 84 days, among them 114 participants were followed-up for 180 days. Additionally, 99 participants were included in the control group and followed up for 180 days. Overall, 86.4% (95% CI 84.1–88.4) of vaccinated participants seroresponded at 28 days post-vaccination (ELISA- GP) with 65% of these seroresponding at 14 days post-vaccination. Among those who seroresponded at 28 days, 90.7% (95% CI 82.0–95.4) were still seropositive at 180 days. The proportion of seropositivity in the unvaccinated group was 0.0% (95% CI 0.0–3.8) at 28 days and 5.4% (95% CI 2.1–13.1) at 180 days post-vaccination. We found weak correlation between ELISA-GP and neutralization at baseline but significant pairwise correlation at 28 days post-vaccination. Among samples analysed for cellular response, only 1 (2.2%) exhibited responses towards the Zaire Ebola glycoprotein (Ebola GP ≥ 10) at baseline, 10 (13.5%) at day 28 post-vaccination and 27 (48.2%) at Day 180.
Conclusions
We found one dose of rVSVΔG-ZEBOV-GP to be highly immunogenic at 28- and 180-days post vaccination among frontline workers in Guinea. We also found a cellular response that increased with time.
Journal Article > ResearchFull Text
N Engl J Med. 2016 January 7; Volume 374 (Issue 1); 23-32.; DOI:10.1056/NEJMoa1504605
Gignoux EM, Azman AS, de Smet M, Azuma P, Massaquoi M, et al.
N Engl J Med. 2016 January 7; Volume 374 (Issue 1); 23-32.; DOI:10.1056/NEJMoa1504605
BACKGROUND
Malaria treatment is recommended for patients with suspected Ebola virus disease (EVD) in West Africa, whether systematically or based on confirmed malaria diagnosis. At the Ebola treatment center in Foya, Lofa County, Liberia, the supply of artemether–lumefantrine, a first-line antimalarial combination drug, ran out for a 12-day period in August 2014. During this time, patients received the combination drug artesunate–amodiaquine; amodiaquine is a compound with anti–Ebola virus activity in vitro. No other obvious change in the care of patients occurred during this period.
METHODS
We fit unadjusted and adjusted regression models to standardized patient-level data to estimate the risk ratio for death among patients with confirmed EVD who were prescribed artesunate–amodiaquine (artesunate–amodiaquine group), as compared with those who were prescribed artemether–lumefantrine (artemether–lumefantrine group) and those who were not prescribed any antimalarial drug (no-antimalarial group).
RESULTS
Between June 5 and October 24, 2014, a total of 382 patients with confirmed EVD were admitted to the Ebola treatment center in Foya. At admission, 194 patients were prescribed artemether–lumefantrine and 71 were prescribed artesunate–amodiaquine. The characteristics of the patients in the artesunate–amodiaquine group were similar to those in the artemether–lumefantrine group and those in the no-antimalarial group. A total of 125 of the 194 patients in the artemether–lumefantrine group (64.4%) died, as compared with 36 of the 71 patients in the artesunate–amodiaquine group (50.7%). In adjusted analyses, the artesunate–amodiaquine group had a 31% lower risk of death than the artemether–lumefantrine group (risk ratio, 0.69; 95% confidence interval, 0.54 to 0.89), with a stronger effect observed among patients without malaria.
CONCLUSIONS
Patients who were prescribed artesunate–amodiaquine had a lower risk of death from EVD than did patients who were prescribed artemether–lumefantrine. However, our analyses cannot exclude the possibility that artemether–lumefantrine is associated with an increased risk of death or that the use of artesunate–amodiaquine was associated with unmeasured patient characteristics that directly altered the risk of death.
Malaria treatment is recommended for patients with suspected Ebola virus disease (EVD) in West Africa, whether systematically or based on confirmed malaria diagnosis. At the Ebola treatment center in Foya, Lofa County, Liberia, the supply of artemether–lumefantrine, a first-line antimalarial combination drug, ran out for a 12-day period in August 2014. During this time, patients received the combination drug artesunate–amodiaquine; amodiaquine is a compound with anti–Ebola virus activity in vitro. No other obvious change in the care of patients occurred during this period.
METHODS
We fit unadjusted and adjusted regression models to standardized patient-level data to estimate the risk ratio for death among patients with confirmed EVD who were prescribed artesunate–amodiaquine (artesunate–amodiaquine group), as compared with those who were prescribed artemether–lumefantrine (artemether–lumefantrine group) and those who were not prescribed any antimalarial drug (no-antimalarial group).
RESULTS
Between June 5 and October 24, 2014, a total of 382 patients with confirmed EVD were admitted to the Ebola treatment center in Foya. At admission, 194 patients were prescribed artemether–lumefantrine and 71 were prescribed artesunate–amodiaquine. The characteristics of the patients in the artesunate–amodiaquine group were similar to those in the artemether–lumefantrine group and those in the no-antimalarial group. A total of 125 of the 194 patients in the artemether–lumefantrine group (64.4%) died, as compared with 36 of the 71 patients in the artesunate–amodiaquine group (50.7%). In adjusted analyses, the artesunate–amodiaquine group had a 31% lower risk of death than the artemether–lumefantrine group (risk ratio, 0.69; 95% confidence interval, 0.54 to 0.89), with a stronger effect observed among patients without malaria.
CONCLUSIONS
Patients who were prescribed artesunate–amodiaquine had a lower risk of death from EVD than did patients who were prescribed artemether–lumefantrine. However, our analyses cannot exclude the possibility that artemether–lumefantrine is associated with an increased risk of death or that the use of artesunate–amodiaquine was associated with unmeasured patient characteristics that directly altered the risk of death.
Journal Article > ResearchFull Text
Nature. 2016 May 4; Volume 533 (Issue 7601); 100-104.; DOI:10.1038/nature17949
Ruibal P, Oestereich L, Ludtke A, Becker-Ziaja B, Wozniak DM, et al.
Nature. 2016 May 4; Volume 533 (Issue 7601); 100-104.; DOI:10.1038/nature17949
Despite the magnitude of the Ebola virus disease (EVD) outbreak in West Africa, there is still a fundamental lack of knowledge about the pathophysiology of EVD. In particular, very little is known about human immune responses to Ebola virus. Here we evaluate the physiology of the human T cell immune response in EVD patients at the time of admission to the Ebola Treatment Center in Guinea, and longitudinally until discharge or death. Through the use of multiparametric flow cytometry established by the European Mobile Laboratory in the field, we identify an immune signature that is unique in EVD fatalities. Fatal EVD was characterized by a high percentage of CD4(+) and CD8(+) T cells expressing the inhibitory molecules CTLA-4 and PD-1, which correlated with elevated inflammatory markers and high virus load. Conversely, surviving individuals showed significantly lower expression of CTLA-4 and PD-1 as well as lower inflammation, despite comparable overall T cell activation. Concomitant with virus clearance, survivors mounted a robust Ebola-virus-specific T cell response. Our findings suggest that dysregulation of the T cell response is a key component of EVD pathophysiology.
Journal Article > ResearchFull Text
Clin Infect Dis. 2015 May 19 (Issue 5)
Strecker T, Palyi B, Ellerbrok H, Jonckheere S, De Clerck H, et al.
Clin Infect Dis. 2015 May 19 (Issue 5)
Reliable reverse-transcriptase polymerase chain reaction (RT-PCR)-based diagnosis of Ebola virus infection currently requires a blood sample obtained by intravenous puncture. During the current Ebola outbreak in Guinea, we evaluated the usability of capillary blood samples collected from fingersticks of patients suspected of having Ebola virus disease (EVD) for field diagnostics during an outbreak emergency.
Journal Article > ResearchFull Text
BMC Med. 2024 November 7; Volume 22 (Issue 1); 523.; DOI:10.1186/s12916-024-03726-z
Watson CH, Gsell PS, Hall Y, Camacho A, Riveros X, et al.
BMC Med. 2024 November 7; Volume 22 (Issue 1); 523.; DOI:10.1186/s12916-024-03726-z
BACKGROUND
Zaire Ebolavirus disease (EVD) outbreaks can be controlled using rVSV-ZEBOV vaccination and other public health measures. People in high-risk areas may have pre-existing antibodies from asymptomatic Ebolavirus exposure that might affect response to rVSV-ZEBOV. Therefore, we assessed the impact pre-existing immunity had on post-vaccination IgG titre, virus neutralisation, and reactogenicity following vaccination.
METHODS
In this prospective cohort study, 2115 consenting close contacts (“proches”) of EVD survivors were recruited. Proches were vaccinated with rVSV-ZEBOV and followed up for 28 days for safety and immunogenicity. Anti-GP IgG titre at baseline and day 28 was assessed by ELISA. Samples from a representative subset were evaluated using live virus neutralisation.
RESULTS
Ten percent were seropositive at baseline. At day 28, IgG in baseline seronegative (GMT 0.106 IU/ml, 95% CI: 0.100 to 0.113) and seropositive (GMT 0.237 IU/ml, 0.210 to 0.267) participants significantly increased from baseline (both p < 0.0001). There was strong correlation between antibody titres and virus neutralisation in day 28 samples (Spearman’s rho 0.75). Vaccinees with baseline IgG antibodies against Zaire Ebolavirus had similar safety profiles to those without detectable antibodies (63.6% vs 66.1% adults experienced any adverse event; 49.1% vs 60.9% in children), with almost all adverse events graded as mild. No serious adverse events were attributed to vaccination. No EVD survivors tested positive for Ebolavirus by RT-PCR.
CONCLUSIONS
These data add further evidence of rVSV-ZEBOV safety and immunogenicity, including in people with pre-existing antibodies from suspected natural ZEBOV infection whose state does not blunt rVSV-ZEBOV immune response. Pre-vaccination serological screening is not required.