Diphtheria Antitoxin Administration, Outcomes, and Safety: Response to a Diphtheria Outbreak in Cox's Bazar, Bangladesh.

BACKGROUND: Diphtheria has re-emerged over the past several years. There is a paucity of data on the administration and safety of diphtheria antitoxin (DAT), the standard treatment for diphtheria. The 2017-2018 outbreak among Rohingya refugees in Bangladesh was the largest in decades. We determined the outcomes of DAT-treated patients and describe the occurrence and risk factors associated with adverse reactions to DAT. METHODS: We conducted a retrospective study at the Médecins Sans Frontières Rubber Garden Diphtheria Treatment Center from December 2017-September 2018. Diphtheria was diagnosed based on the World Health Organization clinical case criteria. High-acuity patients were eligible for DAT. Safety precautions were meticulously maintained. We calculated the presence of adverse events by age, duration of illness, and DAT dosage using bivariate comparisons. RESULTS: We treated 709 patients with DAT; 98% (n = 696) recovered and were discharged. One-fourth (n = 170) had at least 1 adverse reaction. Common reactions included cough (n = 115, 16%), rash (n = 66, 9%), and itching (n = 37, 5%). Three percent (n = 18) had severe hypersensitivity reactions. Five patients died during their DAT infusion or soon afterwards, but no deaths were attributed to DAT. CONCLUSIONS: Outcomes for DAT-treated patients were excellent; mortality was <1%. Adverse reactions occurred in one-quarter of all patients, but most reactions were mild and resolved quickly. DAT can be safely administered in a setting with basic critical care, provided there is continuous patient monitoring during the infusion, staff training on management of adverse effects, and attention to safety precautions.

Changes in Health-Seeking Behavior Did Not Result in Increased All-Cause Mortality During the Ebola Outbreak in Western Area, Sierra Leone.

Little is known about the residual effects of the west African Ebola virus disease (Ebola) epidemic on non-Ebola mortality and health-seeking behavior in Sierra Leone. We conducted a retrospective household survey to estimate mortality and describe health-seeking behavior in Western Area, Sierra Leone, between May 25, 2014, and February 16, 2015. We used two-stage cluster sampling, selected 30 geographical sectors with probability proportional to population size, and sampled 30 households per sector. Survey teams conducted face-to-face interviews and collected information on mortality and health-seeking behavior. We calculated all-cause and Ebola-specific mortality rates and compared health-seeking behavior before and during the Ebola epidemic using χ2 and Fisher's exact tests. Ninety-six deaths, 39 due to Ebola, were reported in 898 households. All-cause and Ebola-specific mortality rates were 0.52 (95% confidence interval [CI] = 0.29-0.76) and 0.19 (95% CI = 0.01-0.38) per 10,000 inhabitants per day, respectively. Of those households that reported a sick family member during the month before the survey, 86% (73/85) sought care at a health facility before the epidemic, compared with 58% (50/86) in February 2015 (P = 0.013). Reported self-medication increased from 4% (3/85) before the epidemic to 23% (20/86) during the epidemic (P = 0.013). Underutilization of health services and increased self-medication did not show a demonstrable effect on non-Ebola-related mortality. Nevertheless, the residual effects of outbreaks need to be taken into account for the future. Recovery efforts should focus on rebuilding both the formalized health system and the population's trust in it.

Successful Control of Ebola Virus Disease: Analysis of Service Based Data from Rural Sierra Leone.

INTRODUCTION: The scale and geographical distribution of the current outbreak in West Africa raised doubts as to the effectiveness of established methods of control. Ebola Virus Disease (EVD) was first detected in Sierra Leone in May 2014 in Kailahun district. Despite high case numbers elsewhere in the country, transmission was eliminated in the district by December 2014. We describe interventions underpinning successful EVD control in Kailahun and implications for EVD control in other areas. METHODS: Internal service data and published reports from response agencies were analysed to describe the structure and type of response activities, EVD case numbers and epidemic characteristics. This included daily national situation reports and District-level data and reports of the Sierra Leone Ministry of Health and Sanitation, and Médecins Sans Frontières (MSF) patient data and internal epidemiological reports. We used EVD case definitions provided by the World Health Organisation over the course of the outbreak. Characteristics assessed included level of response activities and epidemiological features such as reported exposure (funeral-related or not), time interval between onset of illness and admission to the EVD Management Centre (EMC), work-related exposures (health worker or not) and mortality. We compared these characteristics between two time periods--June to July (the early period of response), and August to December (when coverage and quality of response had improved). A stochastic model was used to predict case numbers per generation with different numbers of beds and a varying percentage of community cases detected. RESULTS: There were 652 probable/confirmed EVD cases from June-December 2014 in Kailahun. An EMC providing patient care opened in June. By August 2014 an integrated detection, treatment, and prevention strategy was in place across the district catchment zone. From June-July to August-December 2014 surveillance and contact tracing staff increased from 1.0 to 8.8 per confirmed EVD case, EMC capacity increased from 32 to 100 beds, the number of burial teams doubled, and health promotion activities increased in coverage. These improvements in response were associated with the following changes between the same periods: the proportion of confirmed/probable cases admitted to the EMC increased from 35% to 83% (χ(2) p-value<0·001), the proportion of confirmed patients admitted to the EMC <3 days of symptom onset increased from 19% to 37% (χ(2) p-value <0·001), and reported funeral contact in those admitted decreased from 33% to 16% (χ(2) p-value <0·001). Mathematical modelling confirmed the importance of both patient management capacity and surveillance and contact tracing for EVD control. DISCUSSION: Our findings demonstrate that control of EVD can be achieved using established interventions based on identification and appropriate management of those who are at risk of and develop EVD, including in the context of ongoing transmission in surrounding regions. Key attributes in achieving control were sufficient patient care capacity (including admission to specialist facilities of suspect and probable cases for assessment), integrated with adequate staffing and resourcing of community-based case detection and prevention activities. The response structure and coverage targets we present are of value in informing effective control in current and future EVD outbreaks.

Ebola viral load at diagnosis associates with patient outcome and outbreak evolution.

BACKGROUND: Ebola virus (EBOV) causes periodic outbreaks of life-threatening EBOV disease in Africa. Historically, these outbreaks have been relatively small and geographically contained; however, the magnitude of the EBOV outbreak that began in 2014 in West Africa has been unprecedented. The aim of this study was to describe the viral kinetics of EBOV during this outbreak and identify factors that contribute to outbreak progression. METHODS: From July to December 2014, one laboratory in Sierra Leone processed over 2,700 patient samples for EBOV detection by quantitative PCR (qPCR). Viremia was measured following patient admission. Age, sex, and approximate time of symptom onset were also recorded for each patient. The data was analyzed using various mathematical models to find trends of potential interest. RESULTS: The analysis revealed a significant difference (P = 2.7 × 10(-77)) between the initial viremia of survivors (4.02 log10 genome equivalents [GEQ]/ml) and nonsurvivors (6.18 log10 GEQ/ml). At the population level, patient viral loads were higher on average in July than in November, even when accounting for outcome and time since onset of symptoms. This decrease in viral loads temporally correlated with an increase in circulating EBOV-specific IgG antibodies among individuals who were suspected of being infected but shown to be negative for the virus by PCR. CONCLUSIONS: Our results indicate that initial viremia is associated with outcome of the individual and outbreak duration; therefore, care must be taken in planning clinical trials and interventions. Additional research in virus adaptation and the impacts of host factors on EBOV transmission and pathogenesis is needed.

Transmission of Ebola viruses: what we know and what we do not know.

Available evidence demonstrates that direct patient contact and contact with infectious body fluids are the primary modes for Ebola virus transmission, but this is based on a limited number of studies. Key areas requiring further study include (i) the role of aerosol transmission (either via large droplets or small particles in the vicinity of source patients), (ii) the role of environmental contamination and fomite transmission, (iii) the degree to which minimally or mildly ill persons transmit infection, (iv) how long clinically relevant infectiousness persists, (v) the role that "superspreading events" may play in driving transmission dynamics, (vi) whether strain differences or repeated serial passage in outbreak settings can impact virus transmission, and (vii) what role sylvatic or domestic animals could play in outbreak propagation, particularly during major epidemics such as the 2013-2015 West Africa situation. In this review, we address what we know and what we do not know about Ebola virus transmission. We also hypothesize that Ebola viruses have the potential to be respiratory pathogens with primary respiratory spread.

Ebola outbreak in rural West Africa: epidemiology, clinical features and outcomes.

OBJECTIVE: To describe Ebola cases in the district Ebola management centre of in Kailahun, a remote rural district of Sierra Leone, in terms of geographic origin, patient and hospitalisation characteristics, treatment outcomes and time from symptom onset to admission. METHODS: Data of all Ebola cases from June 23rd to October 5th 2014 were reviewed. Ebola was confirmed by reverse-transcriptase-polymerase-chain-reaction assay. RESULTS: Of 489 confirmed cases (51% male, median age 28 years), 166 (34%) originated outside Kailahun district. Twenty-eight (6%) were health workers: 2 doctors, 11 nurses, 2 laboratory technicians, 7 community health workers and 6 other cadres. More than 50% of patients had fever, headache, abdominal pain, diarrhoea/vomiting. An unusual feature was cough in 40%. Unexplained bleeding was reported in 5%. Outcomes for the 489 confirmed cases were 227 (47%) discharges, 259 (53%) deaths and 3 transfers. Case fatality in health workers (68%) was higher than other occupations (52%, P = 0.05). The median community infectivity time was 6.5 days for both general population and health workers (P = 0.4). CONCLUSIONS: One in three admitted cases originated outside Kailahun district due to limited national access to Ebola management centres - complicating contact tracing, safe burial and disinfection measures. The comparatively high case fatality among health workers requires attention. The community infectivity time needs to be reduced to prevent continued transmission.