Evaluation of cesarean delivery rates and factors associated with cesarean delivery among women enrolled in a pregnancy cohort study at two tertiary hospitals in Thailand.

BACKGROUND: Cesarean delivery rates have increased globally resulting in a public health concern. We estimate rates of cesarean deliveries among Thai women using the World Health Organization (WHO) Robson Classification system and compare rates by Robson group to the Robson guideline for acceptable rates to identify groups that might benefit most from interventions for rate reduction. METHODS: In 2017 and 2018, we established cohorts of pregnant women aged ≥ 18 years seeking prenatal care at two tertiary Thai hospitals and followed them until 6-8 weeks postpartum. Three in-person interviews (enrollment, end of pregnancy, and postpartum) were conducted using structured questionnaires to obtain demographic characteristics, health history, and delivery information. Cesarean delivery indication was classified based on core obstetric variables (parity, previous cesarean delivery, number of fetuses, fetal presentation, gestational week, and onset of labor) assigned to 10 groups according to the Robson Classification. Logistic regression was used to identify factors associated with cesarean delivery among nulliparous women with singleton, cephalic, term pregnancies. RESULTS: Of 2,137 participants, 970 (45%) had cesarean deliveries. The median maternal age at delivery was 29 years (interquartile range, 25-35); 271 (13%) participants had existing medical conditions; and 446 (21%) had pregnancy complications. The cesarean delivery rate varied by Robson group. Multiparous women with > 1 previous uterine scar, with a single cephalic pregnancy, ≥ 37 weeks gestation (group 5) contributed the most (14%) to the overall cesarean rate, whereas those with a single pregnancy with a transverse or oblique lie, including women with previous uterine scars (group 9) contributed the least (< 1%). Factors independently associated with cesarean delivery included age ≥ 25 years, pre-pregnancy obesity, new/worsen medical condition during pregnancy, fetal distress, abnormal labor, infant size for gestational age ≥ 50th percentiles, and self-pay for delivery fees. Women with existing blood conditions were less likely to have cesarean delivery. CONCLUSIONS: Almost one in two pregnancies among women in our cohorts resulted in cesarean deliveries. Compared to WHO guidelines, cesarean delivery rates were elevated in selected Robson groups indicating that tailored interventions to minimize non-clinically indicated cesarean delivery for specific groups of pregnancies may be warranted.

Leveraging International Influenza Surveillance Systems and Programs during the COVID-19 Pandemic.

A network of global respiratory disease surveillance systems and partnerships has been built over decades as a direct response to the persistent threat of seasonal, zoonotic, and pandemic influenza. These efforts have been spearheaded by the World Health Organization, country ministries of health, the US Centers for Disease Control and Prevention, nongovernmental organizations, academic groups, and others. During the COVID-19 pandemic, the US Centers for Disease Control and Prevention worked closely with ministries of health in partner countries and the World Health Organization to leverage influenza surveillance systems and programs to respond to SARS-CoV-2 transmission. Countries used existing surveillance systems for severe acute respiratory infection and influenza-like illness, respiratory virus laboratory resources, pandemic influenza preparedness plans, and ongoing population-based influenza studies to track, study, and respond to SARS-CoV-2 infections. The incorporation of COVID-19 surveillance into existing influenza sentinel surveillance systems can support continued global surveillance for respiratory viruses with pandemic potential.

Feasibility and Performance of Self-Collected Nasal Swabs for Detection of Influenza Virus, Respiratory Syncytial Virus, and Human Metapneumovirus.

BACKGROUND: We assessed performance of participant-collected midturbinate nasal swabs compared to study staff-collected midturbinate nasal swabs for the detection of respiratory viruses among pregnant women in Bangkok, Thailand. METHODS: We enrolled pregnant women aged ≥18 years and followed them throughout the 2018 influenza season. Women with acute respiratory illness self-collected midturbinate nasal swabs at home for influenza viruses, respiratory syncytial viruses (RSV), and human metapneumoviruses (hMPV) real-time RT-PCR testing and the study nurse collected a second midturbinate nasal swab during home visits. Paired specimens were processed and tested on the same day. RESULTS: The majority (109, 60%) of 182 participants were 20-30 years old. All 200 paired swabs had optimal specimen quality. The median time from symptom onsets to participant-collected swabs was 2 days and to staff-collected swabs was also 2 days. The median time interval between the 2 swabs was 2 hours. Compared to staff-collected swabs, the participant-collected swabs were 93% sensitive and 99% specific for influenza virus detection, 94% sensitive and 99% specific for RSV detection, and 100% sensitive and 100% specific for hMPV detection. CONCLUSIONS: Participant-collected midturbinate nasal swabs were a valid alternative approach for laboratory confirmation of influenza-, RSV-, and hMPV-associated illnesses among pregnant women in a community setting.

Performance of Symptom-Based Case Definitions to Identify Influenza Virus Infection Among Pregnant Women in Middle-Income Countries: Findings From the Pregnancy and Influenza Multinational Epidemiologic (PRIME) Study.

BACKGROUND: The World Health Organization (WHO) recommends case definitions for influenza surveillance that are also used in public health research, although their performance has not been assessed in many risk groups, including pregnant women in whom influenza may manifest differently. We evaluated the performance of symptom-based definitions to detect influenza in a cohort of pregnant women in India, Peru, and Thailand. METHODS: In 2017 and 2018, we contacted 11 277 pregnant women twice weekly during the influenza season to identify illnesses with new or worsened cough, runny nose, sore throat, difficulty breathing, or myalgia and collected data on other symptoms and nasal swabs for influenza real-time reverse transcription-polymerase chain reaction (rRT-PCR) testing. We calculated sensitivity, specificity, positive-predictive value, and negative-predictive value of each symptom predictor, WHO respiratory illness case definitions, and a de novo definition derived from results of multivariable modeling. RESULTS: Of 5444 eligible illness episodes among 3965 participants, 310 (6%) were positive for influenza. In a multivariable model, measured fever ≥38°C (adjusted odds ratio [95% confidence interval], 4.6 [3.1-6.8]), myalgia (3.0 [2.2-4.0]), cough (2.7 [1.9-3.9]), and chills (1.6 [1.1-2.4]) were independently associated with influenza illness. A definition based on these 4 (measured fever, cough, chills, or myalgia) was 95% sensitive and 27% specific. The WHO influenza-like illness (ILI) definition was 16% sensitive and 98% specific. CONCLUSIONS: The current WHO ILI case definition was highly specific but had low sensitivity. The intended use of case definitions should be considered when evaluating the tradeoff between sensitivity and specificity.

Human Infection with Avian Influenza A(H9N2) Virus, Cambodia, February 2021.

In February 2021, routine sentinel surveillance for influenza-like illness in Cambodia detected a human avian influenza A(H9N2) virus infection. Investigations identified no recent H9N2 virus infections in 43 close contacts. One chicken sample from the infected child's house was positive for H9N2 virus and genetically similar to the human virus.

Clinical Characteristics of Patients Hospitalized with Coronavirus Disease, Thailand.

Among 11 patients in Thailand infected with severe acute respiratory syndrome coronavirus 2, we detected viral RNA in upper respiratory specimens a median of 14 days after illness onset and 9 days after fever resolution. We identified viral co-infections and an asymptomatic person with detectable virus RNA in serial tests. We describe implications for surveillance.

Association between pediatric asthma care quality and morbidity and English language proficiency in Ohio.

OBJECTIVE: Limited English proficiency can be a barrier to asthma care and is associated with poor outcomes. This study examines whether pediatric patients in Ohio with limited English proficiency experience lower asthma care quality or higher morbidity. METHODS: We used electronic health records for asthma patients aged 2-17 years from a regional, urban, children's hospital in Ohio during 2011-2015. Community-level demographics were included from U.S. Census data. By using chi-square and t-tests, patients with limited English proficiency and bilingual English-speaking patients were compared with English-only patients. Five asthma outcomes-two quality and three morbidity measures-were modeled using generalized estimating equations. RESULTS: The study included 15 352 (84%) English-only patients, 1744 (10%) patients with limited English proficiency, and 1147 (6%) bilingual patients. Pulmonary function testing (quality measure) and multiple exacerbation visits (morbidity measure) did not differ by language group. Compared with English-only patients, bilingual patients had higher odds of ever having an exacerbation visit (morbidity measure) (adjusted odds ratio [aOR], 1.4; 95% confidence interval [CI], 1.2-1.6) but lower odds of admission to intensive care (morbidity measure) (aOR, 0.3; 95% CI, 0.2-0.7), while patients with limited English proficiency did not differ on either factor. Recommended follow-up after exacerbation (quality measure) was higher for limited English proficiency (aOR, 1.8; 95% CI, 1.4-2.3) and bilingual (aOR, 1.6; 95% CI, 1.3-2.1), compared with English-only patients. CONCLUSIONS: In this urban, pediatric population with reliable interpreter services, limited English proficiency was not associated with worse asthma care quality or morbidity.

The cost of influenza-associated hospitalizations and outpatient visits in Kenya.

BACKGROUND: We estimated the cost-per-episode and the annual economic burden associated with influenza in Kenya. METHODS: From July 2013-August 2014, we recruited patients with severe acute respiratory illness (SARI) or influenza-like illness (ILI) associated with laboratory-confirmed influenza from 5 health facilities. A structured questionnaire was used to collect direct costs (medications, laboratory investigations, hospital bed fees, hospital management costs, transportation) and indirect costs (productivity losses) associated with an episode of influenza. We used published incidence of laboratory-confirmed influenza associated with SARI and ILI, and the national population census data from 2014, to estimate the annual national number of influenza-associated hospitalizations and outpatient visits and calculated the annual economic burden by multiplying cases by the mean cost. RESULTS: We enrolled 275 patients (105 inpatients and 170 outpatients). The mean cost-per-episode of influenza was US$117.86 (standard deviation [SD], 88.04) among inpatients; US$114.25 (SD, 90.03) for children < 5 years, and US$137.45 (SD, 76.24) for persons aged ≥5 years. Among outpatients, the mean cost-per-episode of influenza was US$19.82 (SD, 27.29); US$21.49 (SD, 31.42) for children < 5 years, and US$16.79 (SD, 17.30) for persons aged ≥5 years. National annual influenza-associated cost estimates ranged from US$2.96-5.37 million for inpatients and US$5.96-26.35 million for outpatients. CONCLUSIONS: Our findings highlight influenza as causing substantial economic burden in Kenya. Further studies may be warranted to assess the potential benefit of targeted influenza vaccination strategies.

Revision of clinical case definitions: influenza-like illness and severe acute respiratory infection.

The formulation of accurate clinical case definitions is an integral part of an effective process of public health surveillance. Although such definitions should, ideally, be based on a standardized and fixed collection of defining criteria, they often require revision to reflect new knowledge of the condition involved and improvements in diagnostic testing. Optimal case definitions also need to have a balance of sensitivity and specificity that reflects their intended use. After the 2009-2010 H1N1 influenza pandemic, the World Health Organization (WHO) initiated a technical consultation on global influenza surveillance. This prompted improvements in the sensitivity and specificity of the case definition for influenza - i.e. a respiratory disease that lacks uniquely defining symptomology. The revision process not only modified the definition of influenza-like illness, to include a simplified list of the criteria shown to be most predictive of influenza infection, but also clarified the language used for the definition, to enhance interpretability. To capture severe cases of influenza that required hospitalization, a new case definition was also developed for severe acute respiratory infection in all age groups. The new definitions have been found to capture more cases without compromising specificity. Despite the challenge still posed in the clinical separation of influenza from other respiratory infections, the global use of the new WHO case definitions should help determine global trends in the characteristics and transmission of influenza viruses and the associated disease burden.

La formulation de définitions précises de cas cliniques fait partie intégrante d'un processus efficace de surveillance de la santé publique. Alors que ces définitions devraient, dans l'idéal, s'appuyer sur un ensemble standardisé et fixe de critères de définition, elles nécessitent souvent une révision pour tenir compte des nouvelles connaissances relatives à la maladie concernée et des améliorations apportées aux tests diagnostiques. Pour être optimales, les définitions de cas doivent aussi établir un équilibre entre sensibilité et spécificité qui reflète leur utilisation aux fins prévues. À la suite de la pandémie de grippe H1N1 de 2009-2010, l'Organisation mondiale de la Santé (OMS) a lancé une consultation technique sur la surveillance mondiale de la grippe. Cela a conduit à des améliorations concernant la sensibilité et la spécificité de la définition de cas pour la grippe ­ c'est-à-dire une maladie respiratoire dont seule la symptomatologie reste à définir. Le processus de révision n'a pas seulement modifié la définition du syndrome de type grippal pour inclure une liste simplifiée des critères le mieux à même de prédire une infection grippale, il a également permis de clarifier le langage utilisé dans la définition pour en améliorer l'interprétation. Par ailleurs, afin de tenir compte des cas sévères de grippe qui nécessitaient une hospitalisation, une nouvelle définition de cas a été introduite concernant l'infection aigüe sévère des voies respiratoires dans tous les groupes d'âge. Il a été constaté que les nouvelles définitions reflétaient davantage de cas, sans pour autant compromettre la spécificité. S'il est vrai que la distinction clinique de la grippe des autres infections respiratoires continue de poser problème, l'utilisation mondiale des nouvelles définitions de cas de l'OMS devrait permettre de dégager des tendances mondiales concernant les caractéristiques et la transmission des virus grippaux ainsi que la charge de morbidité qui leur est associée.

La elaboración de definiciones precisas de los casos clínicos es una parte fundamental de un proceso efectivo de la vigilancia de la salud pública. Aunque tales definiciones deberían, idealmente, estar basadas en una recopilación estandarizada y fija de criterios de definición, a menudo necesitan una revisión para reflejar el nuevo conocimiento de la enfermedad existente y las mejoras en las pruebas de diagnóstico. Las definiciones óptimas de los casos también deben tener un equilibrio entre sensibilidad y especificidad que refleje su uso previsto. Después de la pandemia de gripe H1N1 en 2009-2010, la Organización Mundial de la Salud (OMS) inició una consulta técnica para la vigilancia mundial de la gripe. Esto dio lugar a mejoras en la sensibilidad y la especificidad de las definiciones de los casos de gripe, es decir, una enfermedad respiratoria que carece de una sintomatología definitoria singular. El proceso de revisión no solo modificó la definición de las enfermedades similares a la gripe para incluir una lista simplificada de los criterios que demostraron ser más predictivos de la infección por gripe, sino que también aclaró el lenguaje utilizado para la definición, con el fin de mejorar su interpretación. Para englobar los casos graves de gripe que requirieron hospitalización, también se desarrolló una nueva definición de los casos de la infección respiratoria aguda grave en todos los grupos de edad. Se ha descubierto que las nuevas definiciones engloban más casos sin comprometer la especificidad. A pesar del desafío que todavía plantea la separación clínica de la gripe de otras infecciones respiratorias, el uso global de las nuevas definiciones de los casos de la OMS debería ayudar a determinar las tendencias mundiales en las características y transmisión de los virus de la gripe y la carga de la enfermedad asociada.

Distribution of influenza virus types by age using case-based global surveillance data from twenty-nine countries, 1999-2014.

BACKGROUND: Influenza disease burden varies by age and this has important public health implications. We compared the proportional distribution of different influenza virus types within age strata using surveillance data from twenty-nine countries during 1999-2014 (N=358,796 influenza cases). METHODS: For each virus, we calculated a Relative Illness Ratio (defined as the ratio of the percentage of cases in an age group to the percentage of the country population in the same age group) for young children (0-4 years), older children (5-17 years), young adults (18-39 years), older adults (40-64 years), and the elderly (65+ years). We used random-effects meta-analysis models to obtain summary relative illness ratios (sRIRs), and conducted meta-regression and sub-group analyses to explore causes of between-estimates heterogeneity. RESULTS: The influenza virus with highest sRIR was A(H1N1) for young children, B for older children, A(H1N1)pdm2009 for adults, and (A(H3N2) for the elderly. As expected, considering the diverse nature of the national surveillance datasets included in our analysis, between-estimates heterogeneity was high (I2>90%) for most sRIRs. The variations of countries' geographic, demographic and economic characteristics and the proportion of outpatients among reported influenza cases explained only part of the heterogeneity, suggesting that multiple factors were at play. CONCLUSIONS: These results highlight the importance of presenting burden of disease estimates by age group and virus (sub)type.

The contribution of respiratory pathogens to fatal and non-fatal respiratory hospitalizations: a pilot study of Taqman Array Cards (TAC) in Kenya.

BACKGROUND: Respiratory diseases cause substantial morbidity and mortality worldwide, with sub-Saharan Africa bearing the greatest burden. Identifying etiologies of respiratory disease is important to inform cost effective treatment, prevention and control strategies. Testing for all of the different pathogens that are potentially associated with respiratory illnesses is challenging. We piloted the use of a multi-pathogen respiratory Taqman Array Cards (TAC) to identify pathogens in respiratory samples collected from non-fatal and fatal cases and their matched asymptomatic controls. METHODS: This is a case control study comparing viral and bacterial pathogens detected among non-fatal and fatal cases to those detected among age and time matched asymptomatic controls. We used McNemar's test to compare proportions of pathogens detected among cases (non-fatal and fatal) to their matched asymptomatic controls. We used Mann-Whitney test to compare the distribution of median Cycle threshold (Ct) values among non-fatal and fatal cases to their corresponding asymptomatic controls. RESULTS: There were 72 fatal and 72 non-fatal cases matched to 72 controls. We identified at least one pathogen in 109/144 (76%) cases and 59/72 (82%) controls. For most pathogens, the median Ct values were lower among cases (fatal and non-fatal) compared to asymptomatic controls. CONCLUSIONS: Similar rates of pathogen detection among cases and controls make interpretation of results challenging. Ct-values might be helpful in interpreting clinical relevance of detected pathogens using multi-pathogen diagnostic tools.

Evaluation of the point-of-care Becton Dickinson Veritor™ Rapid influenza diagnostic test in Kenya, 2013-2014.

BACKGROUND: We evaluated the performance of the Becton Dickinson Veritor™ System Flu A + B rapid influenza diagnostic test (RIDT) to detect influenza viruses in respiratory specimens from patients enrolled at five surveillance sites in Kenya, a tropical country where influenza seasonality is variable. METHODS: Nasal swab (NS) and nasopharyngeal (NP)/oropharyngeal (OP) swabs were collected from patients with influenza like illness and/or severe acute respiratory infection. The sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of the RIDT using NS specimens were evaluated against nasal swabs tested by real time reverse transcription polymerase chain reaction (rRT-PCR). The performance parameter results were expressed as 95% confidence intervals (CI) calculated using binomial exact methods, with P < 0.05 considered significant. Two-sample Z tests were used to test for differences in sample proportions. Analysis was performed using SAS software version 9.3. RESULTS: From July 2013 to July 2014, 3,569 patients were recruited, of which 78.7% were aged <5 years. Overall, 14.4% of NS specimens were influenza-positive by RIDT. RIDT overall sensitivity was 77.1% (95% CI 72.8-81.0%) and specificity was 94.9% (95% CI 94.0-95.7%) compared to rRT-PCR using NS specimens. RIDT sensitivity for influenza A virus compared to rRT-PCR using NS specimens was 71.8% (95% CI 66.7-76.4%) and was significantly higher than for influenza B which was 43.8% (95% CI 33.8-54.2%). PPV ranged from 30%-80% depending on background prevalence of influenza. CONCLUSION: Although the variable seasonality of influenza in tropical Africa presents unique challenges, RIDTs may have a role in making influenza surveillance sustainable in more remote areas of Africa, where laboratory capacity is limited.

Secondary Infections with Ebola Virus in Rural Communities, Liberia and Guinea, 2014-2015.

Persons who died of Ebola virus disease at home in rural communities in Liberia and Guinea resulted in more secondary infections than persons admitted to Ebola treatment units. Intensified monitoring of contacts of persons who died of this disease in the community is an evidence-based approach to reduce virus transmission in rural communities.

Evaluation of case definitions to detect respiratory syncytial virus infection in hospitalized children below 5 years in Rural Western Kenya, 2009-2013.

BACKGROUND: In order to better understand respiratory syncytial virus (RSV) epidemiology and burden in tropical Africa, optimal case definitions for detection of RSV cases need to be identified. METHODS: We used data collected between September 2009 - August 2013 from children aged <5 years hospitalized with acute respiratory Illness at Siaya County Referral Hospital. We evaluated the sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of individual signs, symptoms and standard respiratory disease case definitions (severe acute respiratory illness [SARI]; hospitalized influenza-like illness [hILI]; integrated management of childhood illness [IMCI] pneumonia) to detect laboratory-confirmed RSV infection. We also evaluated an alternative case definition of cough or difficulty breathing plus hypoxia, in-drawing, or wheeze. RESULTS: Among 4714 children hospitalized with ARI, 3810 (81 %) were tested for RSV; and 470 (12 %) were positive. Among individual signs and symptoms, cough alone had the highest sensitivity to detect laboratory-confirmed RSV [96 %, 95 % CI (95-98)]. Hypoxia, wheezing, stridor, nasal flaring and chest wall in-drawing had sensitivities ranging from 8 to 31 %, but had specificities >75 %. Of the standard respiratory case definitions, SARI had the highest sensitivity [83 %, 95 % CI (79-86)] whereas IMCI severe pneumonia had the highest specificity [91 %, 95 % CI (90-92)]. The alternative case definition (cough or difficulty breathing plus hypoxia, in-drawing, or wheeze) had a sensitivity of [55 %, 95 % CI (50-59)] and a specificity of [60 %, 95 % CI (59-62)]. The PPV for all case definitions and individual signs/symptoms ranged from 11 to 20 % while the negative predictive values were >87 %. When we stratified by age <1 year and 1- < 5 years, difficulty breathing, severe pneumonia and the alternative case definition were more sensitive in children aged <1 year [70 % vs. 54 %, p < 0.01], [19 % vs. 11 %, p = 0.01] and [66 % vs. 43 %, p < 0.01] respectively, while non-severe pneumonia was more sensitive [14 % vs. 26 %, p < 0.01] among children aged 1- < 5 years. CONCLUSION: The sensitivity and specificity of different commonly used case definitions for detecting laboratory-confirmed RSV cases varied widely, while the positive predictive value was consistently low. Optimal choice of case definition will depend upon study context and research objectives.

The Role of HIV in the Household Introduction and Transmission of Influenza in an Urban Slum, Nairobi, Kenya, 2008-2011.

BACKGROUND: Little is known about how human immunodeficiency virus (HIV) infection affects influenza transmission within homes in sub-Saharan Africa. METHODS: We used respiratory illness surveillance and HIV testing data gathered in Kibera, an urban slum in Nairobi, Kenya, to examine the impact of HIV status on (1) introducing influenza to the home and (2) transmitting influenza to household contacts. RESULTS: While HIV status did not affect the likelihood of being an influenza index case, household contacts of HIV-infected influenza index cases had twice the risk of developing secondary influenza-like illness than contacts of HIV-negative index cases. CONCLUSIONS: HIV-infected influenza index cases may facilitate transmission of influenza within the home.

Severe Acute Respiratory Illness Deaths in Sub-Saharan Africa and the Role of Influenza: A Case Series From 8 Countries.

BACKGROUND: Data on causes of death due to respiratory illness in Africa are limited. METHODS: From January to April 2013, 28 African countries were invited to participate in a review of severe acute respiratory illness (SARI)-associated deaths identified from influenza surveillance during 2009-2012. RESULTS: Twenty-three countries (82%) responded, 11 (48%) collect mortality data, and 8 provided data. Data were collected from 37 714 SARI cases, and 3091 (8.2%; range by country, 5.1%-25.9%) tested positive for influenza virus. There were 1073 deaths (2.8%; range by country, 0.1%-5.3%) reported, among which influenza virus was detected in 57 (5.3%). Case-fatality proportion (CFP) was higher among countries with systematic death reporting than among those with sporadic reporting. The influenza-associated CFP was 1.8% (57 of 3091), compared with 2.9% (1016 of 34 623) for influenza virus-negative cases (P < .001). Among 834 deaths (77.7%) tested for other respiratory pathogens, rhinovirus (107 [12.8%]), adenovirus (64 [6.0%]), respiratory syncytial virus (60 [5.6%]), and Streptococcus pneumoniae (57 [5.3%]) were most commonly identified. Among 1073 deaths, 402 (37.5%) involved people aged 0-4 years, 462 (43.1%) involved people aged 5-49 years, and 209 (19.5%) involved people aged ≥50 years. CONCLUSIONS: Few African countries systematically collect data on outcomes of people hospitalized with respiratory illness. Stronger surveillance for deaths due to respiratory illness may identify risk groups for targeted vaccine use and other prevention strategies.

Decreased Ebola Transmission after Rapid Response to Outbreaks in Remote Areas, Liberia, 2014.

We measured the reproduction number before and after interventions were implemented to reduce Ebola transmission in 9 outbreaks in Liberia during 2014. We evaluated risk factors for secondary cases and the association between patient admission to an Ebola treatment unit (ETU) and survival. The reproduction number declined 94% from 1.7 (95% CI 1.1-2.6) to 0.1 (95% CI 0.02-0.6) after interventions began. The risk for secondary infections was 90% lower for patients admitted to an ETU (risk ratio 0.1, 95% CI 0.04-0.3) than for those who died in the community. The case-fatality rate was 68% (95% CI 60-74), and ETU admission was associated with a 50% reduction in death (hazard ratio 0.5, 95% CI 0.4-0.8). Isolation and treatment of Ebola patients had the dual benefit of interrupting community transmission and improving survival.

Rapid intervention to reduce Ebola transmission in a remote village - Gbarpolu County, Liberia, 2014.

As late as September 14, 2014, Liberia's Gbarpolu County had reported zero cases of Ebola virus disease (Ebola). On October 25, the Bong County Health Team, a local health department in the Liberian Ministry of Health and Social Welfare (MOHSW), received confirmation of Ebola in a man who had recently left Geleyansiesu, a remote village of approximately 800 residents, after his wife and daughter had died of illnesses consistent with Ebola. MOHSW requested assistance from CDC, the World Health Organization, and other international partners to investigate and confirm the outbreak in Geleyansiesu and begin interventions to interrupt transmission. A total of 22 cases were identified, of which 18 (82%) were laboratory confirmed by real-time polymerase chain reaction. There were 16 deaths (case-fatality rate = 73%). Without road access to or direct telecommunications with the village, interventions had to be tailored to the local context. Public health interventions included 1) education of the community about Ebola, transmission of the virus, signs and symptoms, the importance of isolating ill patients from family members, and the potential benefits of early diagnosis and treatment; 2) establishment of mechanisms to alert health authorities of possibly infected persons leaving the village to facilitate safe transport to the closest Ebola treatment unit (ETU); 3) case investigation, contact tracing, and monitoring of contacts; 4) training in hygienic burial of dead bodies; 5) active case finding and diagnosis; and 6) isolation and limited no-touch treatment in the village of patients unwilling or unable to seek care at an ETU. The findings of this investigation could inform interventions aimed at controlling focal outbreaks in difficult-to-reach communities, which has been identified as an important component of the effort to eliminate Ebola from Liberia.

Community quarantine to interrupt Ebola virus transmission - Mawah Village, Bong County, Liberia, August-October, 2014.

On September 30, 2014, the Bong County health officer notified the county Ebola task force of a growing outbreak of Ebola virus disease (Ebola) in Mawah, a village of approximately 800 residents. During September 9-16, household quarantine had been used by the community in response to a new Ebola infection. Because the infection led to a local outbreak that grew during September 17-20, county authorities suggested community quarantine be considered, and beginning on approximately September 20, the Fuamah District Ebola Task Force (Task Force) engaged Mawah leaders to provide education about Ebola and to secure cooperation for the proposed measures. On September 30, Bong County requested technical assistance to develop strategies to limit transmission in the village and to prevent spread to other areas. The county health team, with support from the Task Force and CDC, traveled to Mawah on October 1 and identified approximately two dozen residents reporting symptoms consistent with Ebola. Because of an ambulance shortage, 2 days were required, beginning October 1, to transport the patients to an Ebola treatment unit in Monrovia. Community quarantine measures, consisting of restrictions on entering or leaving Mawah, regulated river crossings, and market closures, were implemented on October 1. Local leaders raised concerns about availability of medical care and food. The local clinic was reopened on October 11, and food was distributed on October 12. The Task Force reported a total of 22 cases of Ebola in Mawah during September 9-October 2, of which 19 were fatal. During October 3-November 21, no new cases were reported in the village. Involving community members during planning and implementation helped support a safe and effective community quarantine in Mawah.