RESUMO
INTRODUCTION: On November 20, 2019, the Sierra Leone International Health Regulations (IHR) National Focal Point was notified of an exported case of Lassa fever in The Netherlands, by a Dutch doctor who previously practiced in a rural hospital in Sierra Leone. This report describes the extent of the outbreak, possible sources of infection, and the outbreak response measures taken. METHODS: Response measures implemented to control the outbreak included coordination across multiple countries and cities, outbreak investigation, active case finding, contact tracing and monitoring, laboratory investigation, and isolation and treatment of cases. RESULTS: We report a hospital-associated outbreak that resulted in 3 confirmed cases (health workers) and 2 probable cases (patients). The case fatality rate was 60%, whereas the secondary attack rate was 14%. Two cases involved exportations to The Netherlands. Failure to detect the index case and poor adherence to infection prevention and control (IPC) protocols contributed to disease spread. Pregnancy status and nonspecific signs and symptoms of the index case contributed to failure in early case detection. CONCLUSIONS: Rapid activation of national and subnational incident management systems resulted in rapid outbreak control. We recommend regular training for clinicians on surveillance and IPC protocols and strengthening in-country Lassa virus diagnostic capacity.
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Doença pelo Vírus Ebola , Febre Lassa , Surtos de Doenças/prevenção & controle , Feminino , Doença pelo Vírus Ebola/epidemiologia , Humanos , Febre Lassa/diagnóstico , Febre Lassa/epidemiologia , Febre Lassa/prevenção & controle , Vírus Lassa , Países Baixos/epidemiologia , Gravidez , Serra Leoa/epidemiologiaRESUMO
BACKGROUND: Between December 2013 and June 2016, West Africa experienced the largest Ebola virus disease (EVD) outbreak in history. Understanding EVD in pregnancy is important for EVD clinical screening and infection prevention and control. METHODS: We conducted a review of medical records and EVD investigation reports from three districts in Sierra Leone. We report the clinical presentations and maternal and fetal outcomes of six pregnant women with atypical EVD, and subsequent transmission events from perinatal care. RESULTS: The six women (ages 18-38) were all in the third trimester. Each presented with signs and symptoms initially attributed to pregnancy. None met EVD case definition; only one was known at presentation to be a contact of an EVD case. Five women died, and all six fetuses/neonates died. These cases resulted in at least 35 additional EVD cases. CONCLUSIONS: These cases add to the sparse literature focusing on pregnant women with EVD, highlighting challenges and implications for outbreak control. Infected newborns may also present atypically and may shed virus while apparently asymptomatic. Pregnant women identified a priori as contacts of EVD cases require special attention and planning for obstetrical care.
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Doença pelo Vírus Ebola/diagnóstico , Complicações Infecciosas na Gravidez/diagnóstico , Adolescente , Adulto , Surtos de Doenças , Feminino , Doença pelo Vírus Ebola/epidemiologia , Humanos , Recém-Nascido , Gravidez , Complicações Infecciosas na Gravidez/virologia , Saúde Pública , Serra Leoa/epidemiologia , Adulto JovemRESUMO
BACKGROUND: Ebola virus disease (EVD) survivors are at risk for uveitis during convalescence. Vision loss has been observed following uveitis due to cataracts. Since Ebola virus (EBOV) may persist in the ocular fluid of EVD survivors for an unknown duration, there are questions about the safety and feasibility of vision restorative cataract surgery in EVD survivors. METHODS: We conducted a cross-sectional study of EVD survivors anticipating cataract surgery and patients with active uveitis to evaluate EBOV RNA persistence in ocular fluid, as well as vision outcomes post cataract surgery. Patients with aqueous humor that tested negative for EBOV RNA were eligible to proceed with manual small incision cataract surgery (MSICS). FINDINGS: We screened 137 EVD survivors from June 2016 - August 2017 for enrolment. We enrolled 50 EVD survivors; 46 with visually significant cataract, 1 with a subluxated lens, 2 with active uveitis and 1 with a blind painful eye due to uveitis. The median age was 24.0years (IQR 17-35) and 35 patients (70%) were female. The median logMAR visual acuity (VA) was 3.0 (Snellen VA Hand motions; Interquartile Range, IQR: 1.2-3.0, Snellen VA 20/320 - Hand motions). All patients tested negative for EBOV RNA by RT-PCR in aqueous humor/vitreous fluid and conjunctiva at a median of 19months (IQR 18-20) from EVD diagnosis in Phase 1 of ocular fluid sampling and 34months (IQR 32-36) from EVD diagnosis in Phase 2 of ocular fluid sampling. Thirty-four patients underwent MSICS, with a preoperative median VA improvement from hand motions to 20/30 at three-month postoperative follow-up (P<0.001). INTERPRETATION: EBOV persistence by RT-PCR was not identified in ocular fluid or conjunctivae of fifty EVD survivors with ocular disease. Cataract surgery can be performed safely with vision restorative outcomes in patients who test negative for EBOV RNA in ocular fluid specimens. These findings impact the thousands of West African EVD survivors at-risk for ocular complications who may also require eye surgery during EVD convalescence.
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Líquidos Corporais/virologia , Extração de Catarata , Ebolavirus/fisiologia , Olho/virologia , Doença pelo Vírus Ebola/virologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Sobreviventes , Adolescente , Adulto , Catarata , Olho/fisiopatologia , Humanos , Serra Leoa , Resultado do Tratamento , Acuidade Visual , Adulto JovemAssuntos
Ebolavirus , Doença pelo Vírus Ebola/epidemiologia , Atitude , Surtos de Doenças , Epidemias , Humanos , Serra LeoaRESUMO
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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Ebolavirus/isolamento & purificação , Doença pelo Vírus Ebola/virologia , Sêmen/virologia , Adulto , Estudos de Coortes , Estudos Transversais , Ebolavirus/genética , Doença pelo Vírus Ebola/terapia , Humanos , Masculino , RNA Viral/isolamento & purificação , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Serra Leoa , Sobreviventes , Fatores de Tempo , Adulto JovemRESUMO
BACKGROUND: A recombinant adenovirus type-5 vector-based vaccine expressing the glycoprotein of Ebola Zaire Makona variant showed good safety and immunogenicity in a phase 1 trial of healthy Chinese adults. We aimed to assess the safety and immunogenicity of this vaccine in healthy adults in Sierra Leone and to determine the optimal dose. METHODS: We did a single-centre, randomised, double-blind, placebo-controlled, phase 2 clinical trial at Sierra Leone-China Friendship Hospital, Freetown, Sierra Leone. We recruited healthy adults aged 18-50 years who were HIV negative, had no history of Ebola virus infection, and had no previous immunisation with other Ebola vaccine candidates. Participants were sequentially enrolled and randomly assigned (2:1:1), by computer-generated block randomisation (block size of eight), to receive the high-dose vaccine (1·6â×â1011 viral particles), low-dose vaccine (8·0â×â1010 viral particles), or placebo (containing only vaccine excipients, with no viral particles). Participants, investigators, and study staff (except two study pharmacists) were masked from treatment allocation. The primary safety outcome was occurrence of solicited adverse reactions within 7 days of vaccination, analysed by intention to treat. The primary immunogenicity outcome was glycoprotein-specific antibody responses at days 14, 28, and 168 after vaccination, analysed in all vaccinated participants who had blood samples drawn for antibody tests. The trial is registered with the Pan African Clinical Trials Registry, number PACTR201509001259869, and is completed. FINDINGS: During Oct 10-28, 2015, 500 participants were enrolled and randomly assigned to receive the high-dose vaccine (n=250), low-dose vaccine (n=125), or placebo (n=125). 132 (53%) participants in the high-dose group, 60 (48%) in the low-dose group, and 54 (43%) in the placebo group reported at least one solicited adverse reaction within 7 days of vaccination. Most adverse reactions were mild and self-limiting. Solicited injection-site adverse reactions were significantly more frequent in vaccine recipients (65 [26%] in high-dose group and 31 [25%] in low-dose group) than in those receiving placebo (17 [14%]; p=0·0169). Glycoprotein-specific antibody responses were detected from day 14 onwards (geometric mean titre 1251·0 [95% CI 976·6-1602·5] in low-dose group and 1728·4 [1459·4-2047·0] in high-dose group) and peaked at day 28 (1471·8 [1151·0-1881·8] and 2043·1 [1762·4-2368·4]), but declined quickly in the following months (223·3 [148·2-336·4] and 254·2 [185·0-349·5] at day 168). Geometric mean titres in the placebo group remained around 6·0-6·8 throughout the study period. Three serious adverse events (malaria, gastroenteritis, and one fatal asthma episode) were reported in the high-dose vaccine group, but none was deemed related to the vaccine. INTERPRETATION: The recombinant adenovirus type-5 vector-based Ebola vaccine was safe and highly immunogenic in healthy Sierra Leonean adults, and 8·0â×â1010 viral particles was the optimal dose. FUNDING: Chinese Ministry of Science and Technology and the National Health and Family Planning Commission, Beijing Institute of Biotechnology, and Tianjin CanSino Biotechnology.
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Vacinas contra Ebola/efeitos adversos , Doença pelo Vírus Ebola/prevenção & controle , Imunogenicidade da Vacina/imunologia , Adenoviridae , Adulto , Método Duplo-Cego , Vacinas contra Ebola/administração & dosagem , Vacinas contra Ebola/imunologia , Ebolavirus/imunologia , Feminino , Vetores Genéticos , Glicoproteínas/imunologia , Voluntários Saudáveis , Humanos , Masculino , Serra Leoa , Vacinas Sintéticas/administração & dosagem , Vacinas Sintéticas/efeitos adversos , Vacinas Sintéticas/imunologia , Adulto JovemRESUMO
The 2014-2015 West African outbreak of Ebola Virus Disease (EVD) claimed the lives of more than 11,000 people and infected over 27,000 across seven countries. Traditional approaches to containing EVD proved inadequate and new approaches for controlling the outbreak were required. The Ministry of Health & Sanitation and King's Sierra Leone Partnership developed a model for Ebola Holding Units (EHUs) at Government Hospitals in the capital city Freetown. The EHUs isolated screened or referred suspect patients, provided initial clinical care, undertook laboratory testing to confirm EVD status, referred onward positive cases to an Ebola Treatment Centre or negative cases to the general wards, and safely stored corpses pending collection by burial teams. Between 29th May 2014 and 19th January 2015, our five units had isolated approximately 37% (1159) of the 3097 confirmed cases within Western Urban and Rural district. Nosocomial transmission of EVD within the units appears lower than previously documented at other facilities and staff infection rates were also low. We found that EHUs are a flexible and effective model of rapid diagnosis, safe isolation and early initial treatment. We also demonstrated that it is possible for international partners and government facilities to collaborate closely during a humanitarian crisis.
RESUMO
BACKGROUND: Anecdotal evidence suggests that much of the continuing infection of health care workers (HCWs) with Ebola virus during the current outbreak in Sierra Leone has occurred in settings other than Ebola isolation units, and it is likely that some proportion of acquisition by HCWs occurs outside the workplace. There is a critical need to define more precisely the pathways of Ebola infection among HCWs, to optimise measures for reducing risk during current and future outbreaks. METHODS: We conducted a retrospective descriptive study of Ebola acquisition among health workers in Sierra Leone during May-December 2014. The data used were obtained mainly from the national Ebola database, a cross-sectional survey conducted through administration of a structured questionnaire to infected HCWs, and key informant interviews of select health stakeholders. RESULTS: A total of 293 HCWs comprising 277 (95 %) confirmed, 6 (2 %) probable, and 10 (3 %) suspected cases of infection with Ebola virus were enrolled in the study from nine districts of the country. Over half of infected HCWs (153) were nurses; others included laboratory staff (19, 6.5 %), doctors (9, 3.1 %), cleaners and porters (9, 3.1 %), Community Health Officers (8, 2.7 %), and pharmacists (2, 0.7 %). HCW infections were mainly reported from the Western Area (24.9 %), Kailahun (18.4 %), Kenema (17.7 %), and Bombali (13.3 %) districts. Almost half of the infected HCWs (120, 47.4 %) believed that their exposure occurred in a hospital setting. Others believed that they were exposed in the home (48, 19 %), at health centres (45, 17.8 %), or at other types of health facilities (13, 5.1 %). Only 27 (10.7 %) of all HCW infections were associated with Ebola virus disease (EVD) isolation units. Over half (60 %, 150) of infected HCWs said they had been trained in infection prevention and control prior to their infection, whereas 34 % (85) reported that they had not been so trained. CONCLUSIONS: This study demonstrated the perception that most HCW infections are associated with general health care and home settings and not with dedicated EVD settings, which should provide substantial reassurance to HCWs that measures in place at dedicated EVD facilities generally provide substantial protection when fully adhered to.
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Pessoal de Saúde , Doença pelo Vírus Ebola/epidemiologia , Doença pelo Vírus Ebola/transmissão , Adulto , Idoso , Estudos Transversais , Surtos de Doenças/prevenção & controle , Ebolavirus/patogenicidade , Feminino , Pessoal de Saúde/estatística & dados numéricos , Hospitais , Humanos , Masculino , Pessoa de Meia-Idade , Enfermeiras e Enfermeiros/estatística & dados numéricos , Doenças Profissionais/virologia , Médicos , Saúde Pública , Estudos Retrospectivos , Serra Leoa/epidemiologia , Inquéritos e Questionários , Adulto JovemRESUMO
BACKGROUND: The size of the west African Ebola virus disease outbreak led to the urgent establishment of Ebola holding unit facilities for isolation and diagnostic testing of patients with suspected Ebola virus disease. Following the onset of the outbreak in Sierra Leone, patients presenting to Connaught Hospital in Freetown were screened for suspected Ebola virus disease on arrival and, if necessary, were admitted to the on-site Ebola holding unit. Since demand for beds in this unit greatly exceeded capacity, we aimed to improve the selection of patients with suspected Ebola virus disease for admission by identifying presenting clinical characteristics that were predictive of a confirmed diagnosis. METHODS: In this retrospective cohort study, we recorded the presenting clinical characteristics of suspected Ebola virus disease cases admitted to Connaught Hospital's Ebola holding unit. Patients were subsequently classified as confirmed Ebola virus disease cases or non-cases according to the result of Ebola virus reverse-transcriptase PCR (EBOV RT-PCR) testing. The sensitivity, specificity, positive predictive value, negative predictive value, and likelihood ratio of every clinical characteristic were calculated, to estimate the diagnostic accuracy and predictive value of each clinical characteristic for confirmed Ebola virus disease. RESULTS: Between May 29, 2014, and Dec 8, 2014, 850 patients with suspected Ebola virus disease were admitted to the holding unit, of whom 724 had an EBOV RT-PCR result recorded and were included in the analysis. In 464 (64%) of these patients, a diagnosis of Ebola virus disease was confirmed. Fever or history of fever (n=599, 83%), intense fatigue or weakness (n=495, 68%), vomiting or nausea (n=365, 50%), and diarrhoea (n=294, 41%) were the most common presenting symptoms in suspected cases. Presentation with intense fatigue, confusion, conjunctivitis, hiccups, diarrhea, or vomiting was associated with increased likelihood of confirmed Ebola virus disease. Three or more of these symptoms in combination increased the probability of Ebola virus disease by 3·2-fold (95% CI 2·3-4·4), but the sensitivity of this strategy for Ebola virus disease diagnosis was low. In a subgroup analysis, 15 (9%) of 161 confirmed Ebola virus disease cases reported neither a history of fever nor a risk factor for Ebola virus disease exposure. INTERPRETATION: Discrimination of Ebola virus disease cases from patients without the disease is a major challenge in an outbreak and needs rapid diagnostic testing. Suspected Ebola virus disease case definitions that rely on history of fever and risk factors for Ebola virus disease exposure do not have sufficient sensitivity to identify all cases of the disease. FUNDING: None.
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Doença pelo Vírus Ebola/complicações , Doença pelo Vírus Ebola/diagnóstico , Adulto , Confusão/virologia , Conjuntivite Viral/virologia , Diarreia/virologia , Ebolavirus/isolamento & purificação , Fadiga/virologia , Feminino , Febre/virologia , Soluço/virologia , Humanos , Masculino , Pessoa de Meia-Idade , Náusea/virologia , Isolamento de Pacientes , Seleção de Pacientes , Valor Preditivo dos Testes , Estudos Retrospectivos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Serra Leoa , Vômito/virologia , Adulto JovemRESUMO
As of October 31, 2014, the Sierra Leone Ministry of Health and Sanitation had reported 3,854 laboratory-confirmed cases of Ebola virus disease (Ebola) since the outbreak began in May 2014; 199 (5.2%) of these cases were among health care workers. Ebola infection prevention and control (IPC) measures are essential to interrupt Ebola virus transmission and protect the health workforce, a population that is disproportionately affected by Ebola because of its increased risk of exposure yet is essential to patient care required for outbreak control and maintenance of the country's health system at large. To rapidly identify existing IPC resources and high priority outbreak response needs, an assessment by CDC Ebola Response Team members was conducted in six of the 14 districts in Sierra Leone, consisting of health facility observations and structured interviews with key informants in facilities and government district health management offices. Health system gaps were identified in all six districts, including shortages or absence of trained health care staff, personal protective equipment (PPE), safe patient transport, and standardized IPC protocols. Based on rapid assessment findings and key stakeholder input, priority IPC actions were recommended. Progress has since been made in developing standard operating procedures, increasing laboratory and Ebola treatment capacity and training the health workforce. However, further system strengthening is needed. In particular, a successful Ebola outbreak response in Sierra Leone will require an increase in coordinated and comprehensive district-level IPC support to prevent ongoing Ebola virus transmission in household, patient transport, and health facility settings.
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Surtos de Doenças/prevenção & controle , Doença pelo Vírus Ebola/prevenção & controle , Avaliação das Necessidades , Doença pelo Vírus Ebola/epidemiologia , Humanos , Serra Leoa/epidemiologia , Fatores de TempoRESUMO
BACKGROUND: Large-scale measles outbreaks occurred throughout Africa from 2008-2010. In Sierra Leone, in November 2009, preceding a measles supplemental immunization activity (SIA), the largest measles outbreak in a decade started. METHODS: We analyzed data from the national measles case-based surveillance system, developed a susceptibility profile of the population, and calculated vaccine effectiveness (VE) among children 12-59 months of age. RESULTS: From November 1, 2009 to July 13, 2010, 1,094 confirmed cases, including 9 deaths, were reported; 716 (66%) were <5 years of age. B3 genotype was identified. Measles attack rates per 100,000 population were highest among infants aged 6-8 months (56.4) and in Bo district (49.4). Districts with higher estimated SIA coverage tended to have lower attack rates (Spearman Correlation Coefficient=-0.63), p=0.07. Among 473 cases with information on vaccination status, 222 (47%) were unvaccinated; estimated VE was 74%. The 2009 measles SIA led to 165,000 fewer estimated susceptible individuals. CONCLUSIONS: The 2009 measles SIA reduced the overall magnitude of the outbreak, though routine and SIA coverage was insufficient to prevent it entirely. Maintaining high coverage through routine services and SIAs in all districts and conducting follow-up SIAs prior to the end of the low transmission season may prevent future outbreaks.