Publications by authors named "James Bangura"

23 Publications

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Socializing One Health: an innovative strategy to investigate social and behavioral risks of emerging viral threats.

One Health Outlook 2021 May 14;3(1):11. Epub 2021 May 14.

One Health Institute, University of California, Davis, One Shields Ave, Davis, CA, 95616, USA.

In an effort to strengthen global capacity to prevent, detect, and control infectious diseases in animals and people, the United States Agency for International Development's (USAID) Emerging Pandemic Threats (EPT) PREDICT project funded development of regional, national, and local One Health capacities for early disease detection, rapid response, disease control, and risk reduction. From the outset, the EPT approach was inclusive of social science research methods designed to understand the contexts and behaviors of communities living and working at human-animal-environment interfaces considered high-risk for virus emergence. Using qualitative and quantitative approaches, PREDICT behavioral research aimed to identify and assess a range of socio-cultural behaviors that could be influential in zoonotic disease emergence, amplification, and transmission. This broad approach to behavioral risk characterization enabled us to identify and characterize human activities that could be linked to the transmission dynamics of new and emerging viruses. This paper provides a discussion of implementation of a social science approach within a zoonotic surveillance framework. We conducted in-depth ethnographic interviews and focus groups to better understand the individual- and community-level knowledge, attitudes, and practices that potentially put participants at risk for zoonotic disease transmission from the animals they live and work with, across 6 interface domains. When we asked highly-exposed individuals (ie. bushmeat hunters, wildlife or guano farmers) about the risk they perceived in their occupational activities, most did not perceive it to be risky, whether because it was normalized by years (or generations) of doing such an activity, or due to lack of information about potential risks. Integrating the social sciences allows investigations of the specific human activities that are hypothesized to drive disease emergence, amplification, and transmission, in order to better substantiate behavioral disease drivers, along with the social dimensions of infection and transmission dynamics. Understanding these dynamics is critical to achieving health security--the protection from threats to health-- which requires investments in both collective and individual health security. Involving behavioral sciences into zoonotic disease surveillance allowed us to push toward fuller community integration and engagement and toward dialogue and implementation of recommendations for disease prevention and improved health security.
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http://dx.doi.org/10.1186/s42522-021-00036-9DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8122533PMC
May 2021

Human Interactions with Bat Populations in Bombali, Sierra Leone.

Ecohealth 2020 09 11;17(3):292-301. Epub 2020 Nov 11.

Metabiota, Inc., 425 California St., Suite 1200, San Francisco, CA, 94104, USA.

Human contact with bats has been epidemiologically linked to several of the most recent Ebola outbreaks, including the 2014 West Africa epidemic and the 2007 Luebo, Democratic Republic of the Congo, outbreak. While fruit bats remain the likely primary reservoir for Ebola virus (Zaire ebolavirus), recent wildlife surveillance efforts have identified a new species of ebolavirus (Bombali ebolavirus) in microchiropteran insect-eating bats in West and East Africa. Given the role of bats as potential Ebola reservoirs and sources of spillover into human populations, it is critically important to understand the circumstances and behaviors that bring human populations into close contact with bats. This study explores two sites in Bombali, Sierra Leone, where human populations have had close contact with microchiropteran bats via household infestations and fruit bats by hunting practices. Through interviews and focus groups, we identify the knowledge, beliefs, perceptions, and behaviors that may potentially protect or expose individuals to zoonotic spillover through direct and indirect contact with bats. We also describe how this research was used to develop a risk reduction and outreach tool for living safely with bats.
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http://dx.doi.org/10.1007/s10393-020-01502-yDOI Listing
September 2020

COVID-19 treatment in sub-Saharan Africa: If the best is not available, the available becomes the best.

Travel Med Infect Dis 2020 Sep - Oct;37:101878. Epub 2020 Sep 11.

Masanga Medical Research Unit (MMRU), Masanga, Tonkolili District, Sierra Leone; Center of Tropical Medicine and Travel Medicine, Department of Infectious Diseases, Amsterdam University Medical Centers, Amsterdam Infection & Immunity, Amsterdam Public Health, University of Amsterdam, Location AMC, Meibergdreef 9, 1100 DD Amsterdam, Amsterdam, the Netherlands. Electronic address:

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http://dx.doi.org/10.1016/j.tmaid.2020.101878DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7485546PMC
October 2020

Primum non nocere: Potential indirect adverse effects of COVID-19 containment strategies in the African region.

Travel Med Infect Dis 2020 May - Jun;35:101727. Epub 2020 Apr 29.

Masanga Medical Research Unit (MMRU), Masanga, Tonkolili District, Sierra Leone; Center of Tropical Medicine and Travel Medicine, Department of Infectious Diseases, Amsterdam University Medical Centers, Location AMC, Amsterdam Infection & Immunity, Amsterdam Public Health, University of Amsterdam, Amsterdam, the Netherlands. Electronic address:

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http://dx.doi.org/10.1016/j.tmaid.2020.101727DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7189182PMC
July 2020

Isolation of Angola-like Marburg virus from Egyptian rousette bats from West Africa.

Nat Commun 2020 01 24;11(1):510. Epub 2020 Jan 24.

Department of Biological Sciences, Njala University, Njala, Sierra Leone.

Marburg virus (MARV) causes sporadic outbreaks of severe Marburg virus disease (MVD). Most MVD outbreaks originated in East Africa and field studies in East Africa, South Africa, Zambia, and Gabon identified the Egyptian rousette bat (ERB; Rousettus aegyptiacus) as a natural reservoir. However, the largest recorded MVD outbreak with the highest case-fatality ratio happened in 2005 in Angola, where direct spillover from bats was not  shown. Here, collaborative studies by the Centers for Disease Control and Prevention, Njala University, University of California, Davis USAID-PREDICT, and the University of Makeni identify MARV circulating in ERBs in Sierra Leone. PCR, antibody and virus isolation data from 1755 bats of 42 species shows active MARV infection in approximately 2.5% of ERBs. Phylogenetic analysis identifies MARVs that are similar to the Angola strain. These results provide evidence of MARV circulation in West Africa and demonstrate the value of pathogen surveillance to identify previously undetected threats.
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http://dx.doi.org/10.1038/s41467-020-14327-8DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6981187PMC
January 2020

HLA-C-restricted viral epitopes are associated with an escape mechanism from KIR2DL2 NK cells in Lassa virus infection.

EBioMedicine 2019 Feb 30;40:605-613. Epub 2019 Jan 30.

Sorbonne Université, Inserm, CNRS, Centre d'Immunologie et des Maladies Infectieuses (CIMI-Paris), Paris, France. Electronic address:

Background: Lassa virus (LASV) is the etiologic agent of an acute hemorrhagic fever endemic in West Africa. Natural killer (NK) cells control viral infections in part through the interaction between killer cell immunoglobulin-like receptors (KIRs) and their ligands. LASV infection is associated with defective immune responses, including inhibition of NK cell activity in the presence of MHC-class 1-infected target cells.

Methods: We compared individual KIR and HLA-class 1 genotypes of 68 healthy volunteers to 51 patients infected with LASV in Sierra Leone, including 37 survivors and 14 fatalities. Next, potential HLA-C1, HLA-C2, and HLA-Bw4 binding epitopes were in silico screened among LASV nucleoprotein (NP) and envelope glycoprotein (GP). Selected 10-mer peptides were then tested in peptide-HLA stabilization, KIR binding and polyfunction assays.

Findings: LASV-infected patients were similar to healthy controls, except for the inhibitory KIR2DL2 gene. We found a specific increase in the HLA-C1:KIR2DL2 interaction in fatalities (10/11) as compared to survivors (12/19) and controls (19/29). We also identified that strong of NP and GP viral epitopes was only observed with HLA-C molecules, and associated with strong inhibition of degranulation in the presence of KIR2DL NK cells. This inhibitory effect significantly increased in the presence of the vGP variant, detected in 28.1% of LASV sequences.

Interpretation: Our finding suggests that presentation of specific LASV epitopes by HLA-C alleles to the inhibitory KIR2DL2 receptor on NK cells could potentially prevent the killing of infected cells and provides insights into the mechanisms by which LASV can escape NK-cell-mediated immune pressure.
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http://dx.doi.org/10.1016/j.ebiom.2019.01.048DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6413685PMC
February 2019

Transplacental transmission: A rare case of Ebola virus transmission.

Infect Dis Rep 2018 Nov 5;10(3):7725. Epub 2018 Dec 5.

Ministry of Health and Sanitation, Freetown, Sierra Leone.

During the mid-transmission period of the Ebola virus disease (EVD) outbreak in Sierra Leone, a 19-year-old pregnant woman, who was a petty trader in a health facility in Freetown, noticing no fetal movement for the past 3 days, reported to a health facility. Medical history and laboratory testing showed no abnormalities except that she was positive for sickle cell. She was not known to any surveillance team of having any epidemiological link to EVD case. She was induced with oral medications as well as IV infusion. EVD test showed that the fetus was positive to EVD with a high threshold value of 21, while the woman was negative for EVD with a threshold value of 42. The woman was positive to EVD IgG but negative to EVD IgM by ELISA technique. This is a rare EVD case in the period of medium transmission. We conclude that the woman may have come into contact with a low dose of virus not enough to cause a full blown EVD and that her immune system was able to stop the virus from further replication.
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http://dx.doi.org/10.4081/idr.2018.7725DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6297901PMC
November 2018

Author Correction: The discovery of Bombali virus adds further support for bats as hosts of ebolaviruses.

Nat Microbiol 2018 12;3(12):1486

One Health Institute & Karen C. Drayer Wildlife Health Center, School of Veterinary Medicine, University of California, Davis, CA, USA.

In the version of this Article originally published, the bat species for 12 individuals were incorrectly identified in Supplementary Table 1 and 2. After resequencing the MT-CytB and MT-CO1 segments and reviewing the data, the authors have corrected the errors for these 12 animals. In the amended version of the Supplementary Information, Supplementary Tables 1 and 2 have been replaced to include the corrected host species information. None of the 12 bats affected were positive for the Bombali virus, and the conclusions of the study are therefore unchanged.
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http://dx.doi.org/10.1038/s41564-018-0315-3DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7592853PMC
December 2018

The discovery of Bombali virus adds further support for bats as hosts of ebolaviruses.

Nat Microbiol 2018 10 27;3(10):1084-1089. Epub 2018 Aug 27.

One Health Institute & Karen C. Drayer Wildlife Health Center, School of Veterinary Medicine, University of California, Davis, CA, USA.

Here we describe the complete genome of a new ebolavirus, Bombali virus (BOMV) detected in free-tailed bats in Sierra Leone (little free-tailed (Chaerephon pumilus) and Angolan free-tailed (Mops condylurus)). The bats were found roosting inside houses, indicating the potential for human transmission. We show that the viral glycoprotein can mediate entry into human cells. However, further studies are required to investigate whether exposure has actually occurred or if BOMV is pathogenic in humans.
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http://dx.doi.org/10.1038/s41564-018-0227-2DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6557442PMC
October 2018

Virus-encoded miRNAs in Ebola virus disease.

Sci Rep 2018 04 24;8(1):6480. Epub 2018 Apr 24.

Diagnostic Systems Division, U.S. Army Medical Research Institute of Infectious Diseases, Fort Detrick, Frederick, MD, USA.

Ebola virus (EBOV) is a negative-strand RNA virus that replicates in the cytoplasm and causes an often-fatal hemorrhagic fever. EBOV, like other viruses, can reportedly encode its own microRNAs (miRNAs) to subvert host immune defenses. miRNAs are short noncoding RNAs that can regulate gene expression by hybridizing to multiple mRNAs, and viral miRNAs can enhance viral replication and infectivity by regulating host or viral genes. To date, only one EBOV miRNA has been examined in human infection. Here, we assayed mouse, rhesus macaque, cynomolgus macaque, and human samples infected with three EBOV variants for twelve computationally predicted viral miRNAs using RT-qPCR. Ten miRNAs aligned to EBOV variants and were detectable in the four species during disease with several viral miRNAs showing presymptomatic amplification in animal models. miRNA abundances in both the mouse and nonhuman primate models mirrored the human cohort, with miR-1-5p, miR-1-3p, and miR-T3-3p consistently at the highest levels. These striking similarities in the most abundant miRNAs during infection with different EBOV variants and hosts indicate that these miRNAs are potential valuable diagnostic markers and key effectors of EBOV pathogenesis.
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http://dx.doi.org/10.1038/s41598-018-23916-zDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5915558PMC
April 2018

Household Transmission of Ebola Virus: Risks and Preventive Factors, Freetown, Sierra Leone, 2015.

J Infect Dis 2018 07;218(5):757-767

Division of Preparedness and Emerging Infections, National Center for Emerging and Zoonotic Diseases, Centers for Disease Control and Prevention, Anchorage, Alaska.

Background: Knowing risk factors for household transmission of Ebola virus is important to guide preventive measures during Ebola outbreaks.

Methods: We enrolled all confirmed persons with Ebola who were the first case in a household, December 2014-April 2015, in Freetown, Sierra Leone, and their household contacts. Cases and contacts were interviewed, contacts followed prospectively through the 21-day incubation period, and secondary cases confirmed by laboratory testing.

Results: We enrolled 150 index Ebola cases and 838 contacts; 83 (9.9%) contacts developed Ebola during 21-day follow-up. In multivariable analysis, risk factors for transmission included index case death in the household, Ebola symptoms but no reported fever, age <20 years, more days with wet symptoms; and providing care to the index case (P < .01 for each). Protective factors included avoiding the index case after illness onset and a piped household drinking water source (P < .01 for each).

Conclusions: To reduce Ebola transmission, communities should rapidly identify and follow-up all household contacts; isolate those with Ebola symptoms, including those without reported fever; and consider closer monitoring of contacts who provided care to cases. Households could consider efforts to minimize risk by designating one care provider for ill persons with all others avoiding the suspected case.
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http://dx.doi.org/10.1093/infdis/jiy204DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6508068PMC
July 2018

Epidemiology of Ebola Virus Disease in the Western Area Region of Sierra Leone, 2014-2015.

Front Public Health 2017 2;5:33. Epub 2017 Mar 2.

World Health Organization (WHO) Headquarters , Geneva , Switzerland.

Introduction: Western Area (WA) of Sierra Leone including the capital, Freetown, experienced an unprecedented outbreak of Ebola from 2014 to 2015. At the onset of the epidemic, there was little information about the epidemiology, transmission dynamics, and risk factors in urban settings as previous outbreaks were limited to rural/semi-rural settings. This study, therefore, aimed to describe the epidemiology of the outbreak and the factors which had most impact on the transmission of the epidemic and whether there were different drivers from those previously described in rural settings.

Methods: We conducted a descriptive epidemiology study in WA, Sierra Leone using secondary data from the National Ebola outbreak database. We also reviewed the Ebola situation reports, response strategy documents, and other useful documents.

Results: A total of 4,955 Ebola cases were identified between June 2014 and November 2015, although there were reports of cases occurring in WA toward end of May. All wards were affected, and Waterloo Area I (Ward 330), the capital city of Western Area Rural District, recorded the highest numbers of cases (580) and deaths (236). Majority of cases (63.4%) and deaths (66.8%) were in WA Urban District (WAU); 44 cases were imported from other provinces. Only 20% of cases had a history of contact with an Ebola case, and more than 30% were death alerts. Equal numbers of males and females were infected, and very few cases (3.2%) were health workers. Overall, transmission was through contact with infected individuals, and intense transmission occurred at the community level. In WAU, transmission was mostly between neighbors and among inhabitants of shared accommodations. The drivers of transmission included high population movement to and from WA, overcrowding, fear and lack of trust in the response, and negative community behaviors. Transmission was mostly through contact and with limited transmission through sex and breast milk.

Conclusion: The unprecedented outbreak in WA was attributed to delayed detection, inadequate preparedness and response, intense population movements, overcrowding, and unresponsive communities. Anticipation, strengthening preparedness for early detection, and swift and effective response remains critical in mitigating a potential urban explosion of similar future outbreaks.
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http://dx.doi.org/10.3389/fpubh.2017.00033DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5332373PMC
March 2017

Serosurveillance of viral pathogens circulating in West Africa.

Virol J 2016 10 3;13(1):163. Epub 2016 Oct 3.

Diagnostic Systems Division, US Army Medical Research Institute of Infectious Diseases, 1425 Porter Street, Fort Detrick, MD, 21702-5011, USA.

Background: Sub-Saharan Africa is home to a variety of pathogens, but disease surveillance and the healthcare infrastructure necessary for proper management and control are severely limited. Lassa virus, the cause of Lassa fever, a severe hemorrhagic fever in humans is endemic in West Africa. In Sierra Leone at the Kenema Government Hospital Lassa Diagnostic Laboratory, up to 70 % of acute patient samples suspected of Lassa fever test negative for Lassa virus infection. This large amount of acute undiagnosed febrile illness can be attributed in part to an array of hemorrhagic fever and arthropod-borne viruses causing disease that goes undetected and untreated.

Methods: To better define the nature and extent of viral pathogens infecting the Sierra Leonean population, we developed a multiplexed MAGPIX® assay to detect IgG antibodies against Lassa, Ebola, Marburg, Rift Valley fever, and Crimean-Congo hemorrhagic fever viruses as well as pan-assays for flaviviruses and alphaviruses. This assay was used to survey 675 human serum samples submitted to the Lassa Diagnostic Laboratory between 2007 and 2014.

Results: In the study population, 50.2 % were positive for Lassa virus, 5.2 % for Ebola virus, 10.7 % for Marburg virus, 1.8 % for Rift Valley fever virus, 2.0 % for Crimean-Congo hemorrhagic fever virus, 52.9 % for flaviviruses and 55.8 % for alphaviruses.

Conclusions: These data exemplify the importance of disease surveillance and differential diagnosis for viral diseases in Sierra Leone. We demonstrate the endemic nature of some of these viral pathogens in the region and suggest that unrecognized outbreaks of viral infection have occurred.
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http://dx.doi.org/10.1186/s12985-016-0621-4DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5048616PMC
October 2016

Circulating microRNA profiles of Ebola virus infection.

Sci Rep 2016 Apr 21;6:24496. Epub 2016 Apr 21.

Diagnostic Systems Division, U.S. Army Medical Research Institute of Infectious Diseases, Fort Detrick, Frederick, MD, USA.

Early detection of Ebola virus (EBOV) infection is essential to halting transmission and adjudicating appropriate treatment. However, current methods rely on viral identification, and this approach can misdiagnose presymptomatic and asymptomatic individuals. In contrast, disease-driven alterations in the host transcriptome can be exploited for pathogen-specific diagnostic biomarkers. Here, we present for the first time EBOV-induced changes in circulating miRNA populations of nonhuman primates (NHPs) and humans. We retrospectively profiled longitudinally-collected plasma samples from rhesus macaques challenged via intramuscular and aerosol routes and found 36 miRNAs differentially present in both groups. Comparison of miRNA abundances to viral loads uncovered 15 highly correlated miRNAs common to EBOV-infected NHPs and humans. As proof of principle, we developed an eight-miRNA classifier that correctly categorized infection status in 64/74 (86%) human and NHP samples. The classifier identified acute infections in 27/29 (93.1%) samples and in 6/12 (50%) presymptomatic NHPs. These findings showed applicability of NHP-derived miRNAs to a human cohort, and with additional research the resulting classifiers could impact the current capability to diagnose presymptomatic and asymptomatic EBOV infections.
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http://dx.doi.org/10.1038/srep24496DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4838880PMC
April 2016

Notes from the Field: Ebola Virus Disease Response Activities During a Mass Displacement Event After Flooding--Freetown, Sierra Leone, September-November, 2015.

MMWR Morb Mortal Wkly Rep 2016 Feb 26;65(7):188-9. Epub 2016 Feb 26.

Since the start of the Ebola virus disease (Ebola) outbreak in West Africa, Sierra Leone has reported 8,706 confirmed Ebola cases and 3,956 deaths. During September 15-16, 2015, heavy rains flooded the capital, Freetown, resulting in eight deaths, home and property destruction, and thousands of persons in need of assistance. By September 27, approximately 13,000 flood-affected persons registered for flood relief services from the government. On September 17, two stadiums in Freetown were opened to provide shelter and assistance to flood-affected residents; a total of approximately 3,000 persons stayed overnight in both stadiums (Sierra Leone Ministry of Health and Sanitation, personal communication, September 2015). On the same day the stadiums were opened to flood-affected persons, the Ministry of Health and Sanitation (MoHS) and Western Area Ebola Response Center (WAERC) staff members from CDC, the World Health Organization (WHO), and the African Union evaluated the layout, logistics, and services at both stadiums and identified an immediate need to establish Ebola response activities. The patient in the last Ebola case in the Western Area, which includes Freetown, had died 37 days earlier, on August 11; however, transmission elsewhere in Sierra Leone was ongoing, and movement of persons throughout the country was common.
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http://dx.doi.org/10.15585/mmwr.mm6507a4DOI Listing
February 2016

Ebola RNA Persistence in Semen of Ebola Virus Disease Survivors - Final Report.

N Engl J Med 2017 10 14;377(15):1428-1437. Epub 2015 Oct 14.

From the Sierra Leone Ministry of Health and Sanitation (G.F.D., F.Y., F.J., A.H.W., S.J.S., J.B., A.J.), the Sierra Leone Ministry of Defense (F.R.S., T.A.M., M.S.D., B.I., F.S.), and the Sierra Leone Ministry of Social Welfare, Gender, and Children's Affairs (T.D.) - all in Freetown, Sierra Leone; World Health Organization (N.B., S.L.R.M., J.E.M., P.G., N.H., A.E.T., A.A., A.C., M.C., T.W., F.K.E., D.N., A. Banerjee, K.N.D., M. Lamunu, S.L., P.F.) and the Joint United Nations Program on HIV/AIDS (P.O.), Geneva; Chinese Center for Disease Control and Prevention (W.X., H.L., W.L., Y.Z., Yongjian Liu, Yang Liu, K.X., G.W., M. Liang, Q.S., Y.H.) and Beijing Institute of Microbiology and Epidemiology (Y. Lan), Beijing; and the Centers for Disease Control and Prevention, Atlanta (B.K., E.E., C.R., K.B., J.K., N.A., S.D.B., E.M., T.M., B.R.E., A. Brault, J.W., T.S., S.T.N., O.M., U.S.).

Background: Ebola virus has been detected in the semen of men after their recovery from Ebola virus disease (EVD). We report the presence of Ebola virus RNA in semen in a cohort of survivors of EVD in Sierra Leone.

Methods: We enrolled a convenience sample of 220 adult male survivors of EVD in Sierra Leone, at various times after discharge from an Ebola treatment unit (ETU), in two phases (100 participants were in phase 1, and 120 in phase 2). Semen specimens obtained at baseline were tested by means of a quantitative reverse-transcriptase-polymerase-chain-reaction (RT-PCR) assay with the use of the target sequences of NP and VP40 (in phase 1) or NP and GP (in phase 2). This study did not evaluate directly the risk of sexual transmission of EVD.

Results: Of 210 participants who provided an initial semen specimen for analysis, 57 (27%) had positive results on quantitative RT-PCR. Ebola virus RNA was detected in the semen of all 7 men with a specimen obtained within 3 months after ETU discharge, in 26 of 42 (62%) with a specimen obtained at 4 to 6 months, in 15 of 60 (25%) with a specimen obtained at 7 to 9 months, in 4 of 26 (15%) with a specimen obtained at 10 to 12 months, in 4 of 38 (11%) with a specimen obtained at 13 to 15 months, in 1 of 25 (4%) with a specimen obtained at 16 to 18 months, and in no men with a specimen obtained at 19 months or later. Among the 46 participants with a positive result in phase 1, the median baseline cycle-threshold values (higher values indicate lower RNA values) for the NP and VP40 targets were lower within 3 months after ETU discharge (32.4 and 31.3, respectively; in 7 men) than at 4 to 6 months (34.3 and 33.1; in 25), at 7 to 9 months (37.4 and 36.6; in 13), and at 10 to 12 months (37.7 and 36.9; in 1). In phase 2, a total of 11 participants had positive results for NP and GP targets (samples obtained at 4.1 to 15.7 months after ETU discharge); cycle-threshold values ranged from 32.7 to 38.0 for NP and from 31.1 to 37.7 for GP.

Conclusions: These data showed the long-term presence of Ebola virus RNA in semen and declining persistence with increasing time after ETU discharge. (Funded by the World Health Organization and others.).
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http://dx.doi.org/10.1056/NEJMoa1511410DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5798881PMC
October 2017

Understanding the emergence of ebola virus disease in sierra leone: stalking the virus in the threatening wake of emergence.

PLoS Curr 2015 Apr 20;7. Epub 2015 Apr 20.

Metabiota Inc., Silver Spring and San Francisco, USA.

Since Ebola Virus Disease (EVD) was first identified in 1976 in what is now the Democratic Republic of Congo, and despite the numerous outbreaks recorded to date, rarely has an epidemic origin been identified. Indeed, among the twenty-one most documented EVD outbreaks in Africa, an index case has been identified four times, and hypothesized in only two other instances. The initial steps of emergence and spread of a virus are critical in the development of a potential outbreak and need to be thoroughly dissected and understood in order to improve on preventative strategies. In the current West African outbreak of EVD, a unique index case has been identified, pinpointing the geographical origin of the epidemic in Guinea. Herein, we provide an accounting of events that serve as the footprint of EVD emergence in Sierra Leone and a road map for risk mitigation fueled by lessons learned.
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http://dx.doi.org/10.1371/currents.outbreaks.9a6530ab7bb9096b34143230ab01cdefDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4423925PMC
April 2015

Tactics and strategies for managing Ebola outbreaks and the salience of immunization.

Comput Math Methods Med 2015 10;2015:736507. Epub 2015 Feb 10.

Metabiota Inc., Kenema Government Hospital, Kenema, Sierra Leone ; Sorbonne Université, UPMC, Université de Paris 06, CR7, CIMI-Paris, 75005 Paris, France.

We present a stochastic transmission chain simulation model for Ebola viral disease (EVD) in West Africa, with the salutary result that the virus may be more controllable than previously suspected. The ongoing tactics to detect cases as rapidly as possible and isolate individuals as safely as practicable is essential to saving lives in the current outbreaks in Guinea, Liberia, and Sierra Leone. Equally important are educational campaigns that reduce contact rates between susceptible and infectious individuals in the community once an outbreak occurs. However, due to the relatively low R 0 of Ebola (around 1.5 to 2.5 next generation cases are produced per current generation case in naïve populations), rapid isolation of infectious individuals proves to be highly efficacious in containing outbreaks in new areas, while vaccination programs, even with low efficacy vaccines, can be decisive in curbing future outbreaks in areas where the Ebola virus is maintained in reservoir populations.
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http://dx.doi.org/10.1155/2015/736507DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4338386PMC
October 2015

A tribute to Sheik Humarr Khan and all the healthcare workers in West Africa who have sacrificed in the fight against Ebola virus disease: Mae we hush.

Antiviral Res 2014 Nov 6;111:33-5. Epub 2014 Sep 6.

Tulane University Health Sciences Center, New Orleans, USA.

The Kenema Government Hospital Lassa Fever Ward in Sierra Leone, directed since 2005 by Dr. Sheikh Humarr Khan, is the only medical unit in the world devoted exclusively to patient care and research of a viral hemorrhagic fever. When Ebola virus disease unexpectedly appeared in West Africa in late 2013 and eventually spread to Kenema, Khan and his fellow healthcare workers remained at their posts, providing care to patients with this devastating illness. Khan and the chief nurse, Mbalu Fonnie, became infected and died at the end of July, a fate that they have sadly shared with more than ten other healthcare workers in Kenema and hundreds across the region. This article pays tribute to Sheik Humarr Khan, Mbalu Fonnie and all the healthcare workers who have acquired Ebola virus disease while fighting the epidemic in West Africa. Besides the emotional losses, the death of so many skilled and experienced healthcare workers will severely impair health care and research in affected regions, which can only be restored through dedicated, long-term programs.
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http://dx.doi.org/10.1016/j.antiviral.2014.09.001DOI Listing
November 2014

Lassa hemorrhagic fever in a late term pregnancy from northern Sierra Leone with a positive maternal outcome: case report.

Virol J 2011 Aug 15;8:404. Epub 2011 Aug 15.

Department of Microbiology and Immunology, Tulane University, New Orleans, Louisiana, USA.

Lassa fever (LF) is a devastating viral disease prevalent in West Africa. Efforts to take on this public health crisis have been hindered by lack of infrastructure and rapid field deployable diagnosis in areas where the disease is prevalent. Recent capacity building at the Kenema Government Hospital Lassa Fever Ward (KGH LFW) in Sierra Leone has lead to a major turning point in the diagnosis, treatment and study of LF. Herein we present the first comprehensive rapid diagnosis and real time characterization of an acute hemorrhagic LF case at KGH LFW. This case report focuses on a third trimester pregnant Sierra Leonean woman from the historically non-endemic Northern district of Tonkolili who survived the illness despite fetal demise. Employed in this study were newly developed recombinant LASV Antigen Rapid Test cassettes and dipstick lateral flow immunoassays (LFI) that enabled the diagnosis of LF within twenty minutes of sample collection. Deregulation of overall homeostasis, significant hepatic and renal system involvement, and immunity profiles were extensively characterized during the course of hospitalization. Rapid diagnosis, prompt treatment with a full course of intravenous (IV) ribavirin, IV fluids management, and real time monitoring of clinical parameters resulted in a positive maternal outcome despite admission to the LFW seven days post onset of symptoms, fetal demise, and a natural still birth delivery. These studies solidify the growing rapid diagnostic, treatment, and surveillance capabilities at the KGH LF Laboratory, and the potential to significantly improve the current high mortality rate caused by LF. As a result of the growing capacity, we were also able to isolate Lassa virus (LASV) RNA from the patient and perform Sanger sequencing where we found significant genetic divergence from commonly circulating Sierra Leonean strains, showing potential for the discovery of a newly emerged LASV strain with expanded geographic distribution. Furthermore, recent emergence of LF cases in Northern Sierra Leone highlights the need for superior diagnostics to aid in the monitoring of LASV strain divergence with potentially increased geographic expansion.
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http://dx.doi.org/10.1186/1743-422X-8-404DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3177908PMC
August 2011

Capacity building permitting comprehensive monitoring of a severe case of Lassa hemorrhagic fever in Sierra Leone with a positive outcome: case report.

Virol J 2011 Jun 20;8:314. Epub 2011 Jun 20.

Tulane University Department of Microbiology and Immunology, New Orleans, LA, USA.

Lassa fever is a neglected tropical disease with a significant impact on the health care system of endemic West African nations. To date, case reports of Lassa fever have focused on laboratory characterisation of serological, biochemical and molecular aspects of the disease imported by infected individuals from Western Africa to the United States, Canada, Europe, Japan and Israel. Our report presents the first comprehensive real time diagnosis and characterization of a severe, hemorrhagic Lassa fever case in a Sierra Leonean individual admitted to the Kenema Government Hospital Lassa Fever Ward. Fever, malaise, unresponsiveness to anti-malarial and antibiotic drugs, followed by worsening symptoms and onset of haemorrhaging prompted medical officials to suspect Lassa fever. A recombinant Lassa virus protein based diagnostic was employed in diagnosing Lassa fever upon admission. This patient experienced a severe case of Lassa hemorrhagic fever with dysregulation of overall homeostasis, significant liver and renal system involvement, the interplay of pro- and anti-inflammatory cytokines during the course of hospitalization and an eventual successful outcome. These studies provide new insights into the pathophysiology and management of this viral illness and outline the improved infrastructure, research and real-time diagnostic capabilities within LASV endemic areas.
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http://dx.doi.org/10.1186/1743-422X-8-314DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3283910PMC
June 2011
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