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1.
J Microbiol Biol Educ ; 24(2)2023 Aug.
Article in English | MEDLINE | ID: mdl-37614894

ABSTRACT

Science literacy has many personal and societal benefits that allows for better informed decision-making. Although the importance of science literacy is recognized globally, there are many challenges associated with its promotion. Scientists are more frequently engaging with nonscientific audiences through public outreach activities and with increasing support from institutions and professional societies. This is especially true regarding microbiologists and other related professionals since the start of the global 2019 coronavirus disease pandemic heightened the need to convey novel and rapidly evolving scientific information to lay audiences. The means by which professionals engage with these audiences affect the efficacy of the relay of scientific information. One method of engagement is the "ambassador approach," which aims to establish dialogue among different groups of people and scientists. In this perspective article, we discuss this approach, highlighting activities for the promotion of science literacy organized by the American Society for Microbiology Ambassador Program and similar programs of other scientific societies. We discuss the benefits and challenges of implementing an ambassador approach, propose potential improvements that could be made to existing programs promoting science literacy, and ultimately advocate for increased implementation of science ambassador programs.

2.
Health Secur ; 20(6): 488-496, 2022.
Article in English | MEDLINE | ID: mdl-36383124

ABSTRACT

Control of infectious diseases requires the handling of infectious materials by both clinical and public health laboratories with exposure risks for laboratory personnel and environment. A comprehensive tool for assessing the capacity to manage these risks could enable the development of action plans for mitigation. Under the framework of the Global Health Security Agenda action package for biosafety and biosecurity, the authors developed a tool dedicated to assessing laboratory biosafety and biosecurity. The Biosafety and Biosecurity Laboratory Assessment Tool (BSS LAT) assesses the status of all laboratory biosafety core requirements across 10 different modules. It consists of a standardized spreadsheet-based tool that provides automatic scoring. It is designed to support national, regional, and global efforts to strengthen biosafety in clinical, public health, and veterinary laboratories. The BSS LAT was first used in Burkina Faso in collaboration with the African Society for Laboratory Medicine and the US Centers for Disease Control and Prevention to support the country in strengthening their biorisk management system. Since then, it has been successfully used in other countries (ie, Armenia, Burundi, Cameroon, Ghana, Guinea, Kazakhstan, Liberia), various settings (medical and veterinary laboratories), and translated into several languages (eg, English, French, Russian). The BSS LAT is a multipurpose tool that assists with standardization of biosafety and biosecurity requirements for all laboratories working with infectious materials, serves as a self-assessment guide for laboratories to develop improvement plans and reinforce capacities, and serves as a training guide for individual laboratories and networks or at the national level. The BSS LAT can also be used as a monitoring tool for the assessment of biosafety and biosecurity across all laboratories working with infectious materials at the national, regional, and global levels.


Subject(s)
Containment of Biohazards , Laboratory Personnel , Humans , Laboratories , Global Health , Burkina Faso
3.
Health Secur ; 20(6): 479-487, 2022.
Article in English | MEDLINE | ID: mdl-36399610

ABSTRACT

The Global Health Security Agenda and the International Health Regulations (2005) recommend that countries strengthen the capacity of their national laboratory systems to comply with the International Health Regulations. To efficiently and effectively direct these efforts, the US Centers for Disease Control and Prevention-in collaboration with the Ministry of Health Directorate of Laboratories, the African Society for Laboratory Medicine, and Integrated Quality Laboratory Service-assessed Burkina Faso's national laboratory system using the World Health Organization Laboratory Assessment Tool. Based on gaps observed in biorisk management, the Biosafety and Biosecurity Laboratory Assessment Tool (BSS LAT) was developed to assess 10 public laboratories handling dangerous pathogens. This tool uses a specific scoring matrix with quantitative output. Composite assessment scores for the 9 primary modules (capacity areas) were reported, with the highest scores reported in cleaning, disinfection, sterilization, waste management (42%), and good laboratory practices (40%), and the lowest scores in biosecurity/biosafety (33%), documents/regulations (18%), emergency management (16%), and risk management (5%). To address challenges identified in the assessments, a set of activities was planned with a focus on biorisk management. Results from an evaluation conducted 1 year later, using the BSS LAT, showed an increase in the average score of all indicators from 25% to 45% and an increase in the biorisk management module score from 5% to 35%. This evaluation process was a decisive step toward strengthening the capacity of the laboratory system in Burkina Faso. Global Health Security Agenda investments and activities have made a lasting impact on improving biosafety and biosecurity in public health laboratories. To ensure sustainability, a strong laboratory quality management program based on a mentorship system is greatly needed.


Subject(s)
Containment of Biohazards , Global Health , Humans , Containment of Biohazards/methods , Laboratories , World Health Organization , Risk Management
4.
IJID Reg ; 2: 82-89, 2022 Mar.
Article in English | MEDLINE | ID: mdl-35757077

ABSTRACT

Background: The lack of rapid, sensitive and affordable diagnostic tests that can distinguish a wide variety of respiratory pathogens at the point of care is an obstacle to the rapid implementation of control measures following events and epidemics. In addition, the absence of a standardized case definition to differentiate putative aetiologies is a challenge to assessing the burden of disease. This study aimed to identify the clinical spectrum of respiratory pathogens commonly associated with respiratory tract infections in the context of disease surveillance. Methods: Data obtained from prospective hospital-based severe acute respiratory infection surveillance among children aged <5 years from November 2010 to July 2013 were used in this study. Results: Intercostal recession and dyspnoea were predictive of respiratory syncytial virus (RSV) infection, whereas headache and chills were more often observed during influenza A infection. Male patients were at a higher risk for RSV infection than female patients. Productive cough, chills, sweating and weight loss were significantly associated with Streptococcus pneumoniae infection. The presence of fever did not necessarily indicate RSV infection. Conclusions: Combined with other examinations, this study shows the value of including the syndromic approach in the panel of diagnostic criteria for rapid identification of the risk of infectious diseases in areas where laboratory diagnostics are challenging. Given the current situation with coronavirus disease 2019, this approach may help decision makers to implement appropriate control measures.

5.
One Health ; 13: 100351, 2021 Dec.
Article in English | MEDLINE | ID: mdl-34926781

ABSTRACT

INTRODUCTION: Early warning and objective evidence of systematic errors in laboratory diagnosis ensures evidence based corrective and preventive actions that instill patient safety and confidence. External quality assessment contributes significantly to the above as an essential component of laboratory quality assurance. However, implementation of External Quality Assessment in resource-limited settings is challenged by high costs of enrolling in international schemes. To ensure sustainability, a National External Quality Assessment Program in Armenia was developed using a One Health approach. METHODS: Through engagement of stakeholders from Ministry of Health and Department of Agriculture under Ministry of Economy the government of Armenia started the implementation of the Armenia Laboratory External Quality Assessment (ALEQA) program. Policies and procedures were defined, a web interface for return of results and feedback reporting was created. A training was offered for characterization of simulated samples for bacterial pathogens. Following a pilot survey, the program was successfully scaled up, with later addition of a Brucella serology discipline. RESULTS: The return rate of results was 100% for all surveys. There was an improvement in the performance of the laboratories from the 2015 to the 2019 surveys. The bacterial pathogens EQA survey's, was interrupted between 2017 and 2019. The Brucella Serology survey showed 77% of the 26 participating laboratories had satisfactory performance. CONCLUSION: This is one of the few National EQA Programs that have embraced the One Health approach to improve reach of EQA Programs in resource-limited settings in both human and veterinary laboratories.

6.
Front Public Health ; 9: 609107, 2021.
Article in English | MEDLINE | ID: mdl-34368035

ABSTRACT

The pervasive nature of infections causing major outbreaks have elevated biosafety and biosecurity as a fundamental component for resilient national laboratory systems. In response to international health security demands, the Global Health Security Agenda emphasizes biosafety as one of the prerequisites to respond effectively to infectious disease threats. However, biosafety management systems (BMS) in low-medium income countries (LMIC) remain weak due to fragmented implementation strategies. In addition, inefficiencies in implementation have been due to limited resources, inadequate technical expertise, high equipment costs, and insufficient political will. Here we propose an approach to developing a strong, self-sustaining BMS based on extensive experience in LMICs. A conceptual framework incorporating 15 key components to guide implementers, national laboratory leaders, global health security experts in building a BMS is presented. This conceptual framework provides a holistic and logical approach to the development of a BMS with all critical elements. It includes a flexible planning matrix with timelines easily adaptable to different country contexts as examples, as well as resources that are critical for developing sustainable technical expertise.


Subject(s)
Containment of Biohazards , Global Health , Disease Outbreaks , Humans , Laboratories , Poverty
7.
One Health ; 13: 100278, 2021 Dec.
Article in English | MEDLINE | ID: mdl-34189238

ABSTRACT

BACKGROUND: The ability to rapidly detect emerging and re-emerging threats relies on a strong network of laboratories providing high quality testing services. Improving laboratory quality systems to ensure that these laboratories effectively play their critical role using a tailored stepwise approach can assist them to comply with the World Health Organization's (WHO) International Health Regulations (IHRs) and the World Organization for Animal Health's (OIE) guidelines. METHODS: Fifteen (15) laboratories in Armenia's human and veterinary laboratory networks were enrolled into a quality management system strengthening programme from 2017 to 2020. Training was provided for key staff, resulting in an implementation plan developed to address gaps. Routine mentorship visits were conducted. Audits were undertaken at baseline and post-implementation using standardised checklists to assess laboratory improvements. RESULTS: Baseline audit general indicator scores ranged from 21% to 46% for human laboratories and 37% to 60% for the veterinary laboratories. Following implementation scores improved ranging from 7 to 39% for human laboratories and 12% to 19% for veterinary laboratories. CONCLUSION: In general, there has been improvement for both human and veterinary laboratories in the areas of QMS implementation, particularly in organizational structure, human resources, equipment management, supply chain and data management. Central facilities developed systems that are ready for international accreditation. This One Health strengthening project ensured simultaneous strengthening of both human and veterinary laboratories which is not a common approach.

8.
PLoS One ; 13(11): e0205124, 2018.
Article in English | MEDLINE | ID: mdl-30462659

ABSTRACT

BACKGROUND: Few comprehensive data exist regarding the epidemiology of severe acute respiratory infections (SARI) in low income countries. This study aimed at identifying etiologies and describing clinical features of SARI-associated hospitalization in Madagascar. METHODS: It is a prospective surveillance of SARI in 2 hospitals for 3 years. Nasopharyngeal swabs, sputum, and blood were collected from SARI patients enrolled and tested for viruses and bacteria. Epidemiological and clinical information were obtained from case report forms. RESULTS: Overall, 876 patients were enrolled in the study, of which 83.1% (728/876) were tested positive for at least one pathogen. Viral and bacterial infections occurred in 76.1% (667/876) and 35.8% (314/876) of tested samples, respectively. Among all detected viruses, respiratory syncytial virus (RSV) was the most common (37.7%; 348/924) followed by influenza virus A (FLUA, 18.4%; 170/924), rhinovirus (RV, 13.5%; 125/924), and adenovirus (ADV, 8.3%; 77/924). Among bacteria, Streptococcus pneumoniae (S. pneumoniae, 50.3%, 189/370) was the most detected followed by Haemophilus influenzae type b (Hib, 21.4%; 79/370), and Klebsiella (4.6%; 17/370). Other Streptococcus species were found in 8.1% (30/370) of samples. Compared to patients aged less than 5 years, older age groups were significantly less infected with RSV. On the other hand, patients aged more than 64 years (OR = 3.66) were at higher risk to be infected with FLUA, while those aged 15-29 years (OR = 3.22) and 30-64 years (OR = 2.39) were more likely to be infected with FLUB (influenza virus B). CONCLUSION: The frequency of influenza viruses detected among SARI patients aged 65 years and more highlights the need for health authorities to develop strategies to reduce morbidity amongst at-risk population through vaccine recommendation. Amongst young children, the demonstrated burden of RSV should guide clinicians for a better case management of children. These findings reveal the need to develop point-of-care tests to avoid overuse of antibiotics and to promote vaccine that could reduce drastically the RSV hospitalizations.


Subject(s)
Epidemiological Monitoring , Hospitals , Respiratory Tract Infections/epidemiology , Acute Disease , Adolescent , Adult , Aged , Aged, 80 and over , Child , Child, Preschool , Female , Hospitalization , Humans , Infant , Infant, Newborn , Logistic Models , Madagascar/epidemiology , Male , Prevalence , Respiratory Tract Infections/microbiology , Respiratory Tract Infections/virology , Young Adult
9.
Influenza Other Respir Viruses ; 9(3): 101-9, 2015 May.
Article in English | MEDLINE | ID: mdl-25711873

ABSTRACT

BACKGROUND: The seasonal drivers of influenza activity remain debated in tropical settings where epidemics are not clearly phased. Antananarivo is a particularly interesting case study because it is in Madagascar, an island situated in the tropics and with quantifiable connectivity levels to other countries. OBJECTIVES: We aimed at disentangling the role of environmental forcing and population fluxes on influenza seasonality in Madagascar. METHODS: We compiled weekly counts of laboratory-confirmed influenza-positive specimens for the period 2002 to 2012 collected in Antananarivo, with data available from sub-Saharan countries and countries contributing most foreign travelers to Madagascar. Daily climate indicators were compiled for the study period. RESULTS: Overall, influenza activity detected in Antananarivo predated that identified in temperate Northern Hemisphere locations. This activity presented poor temporal matching with viral activity in other countries from the African continent or countries highly connected to Madagascar excepted for A(H1N1)pdm09. Influenza detection in Antananarivo was not associated with travel activity and, although it was positively correlated with all climatic variables studied, such association was weak. CONCLUSIONS: The timing of influenza activity in Antananarivo is irregular, is not driven by climate, and does not align with that of countries in geographic proximity or highly connected to Madagascar. This work opens fresh questions regarding the drivers of influenza seasonality globally particularly in mid-latitude and less-connected regions to tailor vaccine strategies locally.


Subject(s)
Influenza A Virus, H1N1 Subtype , Influenza A Virus, H3N2 Subtype , Influenza B virus , Influenza, Human/epidemiology , Climate , Epidemics , Humans , Influenza Vaccines , Influenza, Human/virology , Madagascar/epidemiology , Seasons , Sentinel Surveillance , Time Factors , Travel
10.
PLoS One ; 8(9): e72839, 2013.
Article in English | MEDLINE | ID: mdl-24069161

ABSTRACT

BACKGROUND: Acute respiratory infections are a leading cause of infectious disease-related morbidity, hospitalisation and mortality among children worldwide, and particularly in developing countries. In these low-income countries, most patients with acute respiratory infection (ARI), whether it is mild or severe, are still treated empirically. The aim of the study was to evaluate the risk factors associated with the evolution and outcome of respiratory illnesses in patients aged under 5 years old. MATERIALS AND METHODS: We conducted a prospective study in a paediatric ward in Antananarivo from November 2010 to July 2012 including patients under 5 years old suffering from respiratory infections. We collected demographic, socio-economic, clinical and epidemiological data, and samples for laboratory analysis. Deaths, rapid progression to respiratory distress during hospitalisation, and hospitalisation for more than 10 days were considered as severe outcomes. We used multivariate analysis to study the effects of co-infections. RESULTS: From November 2010 to July 2012, a total of 290 patients were enrolled. Co-infection was found in 192 patients (70%). Co-infections were more frequent in children under 36 months, with a significant difference for the 19-24 month-old group (OR: 8.0). Sixty-nine percent (230/290) of the patients recovered fully and without any severe outcome during hospitalisation; the outcome was scored as severe for 60 children and nine patients (3%) died. Risk factors significantly associated with worsening evolution during hospitalisation (severe outcome) were admission at age under 6 months (OR = 5.3), comorbidity (OR = 4.6) and low household income (OR = 4.1). CONCLUSION: Co-mordidity, low-income and age under 6 months increase the risk of severe outcome for children infected by numerous respiratory pathogens. These results highlight the need for implementation of targeted public health policy to reduce the contribution of respiratory diseases to childhood morbidity and mortality in low income countries.


Subject(s)
Pediatrics/statistics & numerical data , Respiratory Tract Infections/epidemiology , Child, Preschool , Female , Hospitals/statistics & numerical data , Humans , Infant , Madagascar , Male , Prospective Studies , Risk Factors
11.
J Infect Dis ; 206 Suppl 1: S140-7, 2012 Dec 15.
Article in English | MEDLINE | ID: mdl-23169961

ABSTRACT

BACKGROUND: Madagascar was one of the first African countries to be affected by the 2009 pandemic of influenza A virus subtype H1N1 [A(H1N1)pdm2009] infection. The outbreak started in the capital city, Antananarivo, and then spread throughout the country from October 2009 through February 2010. METHODS: Specimens from patients presenting with influenza-like illness were collected and shipped to the National Influenza Center in Madagascar for analyses, together with forms containing patient demographic and clinical information. RESULTS: Of the 2303 specimens tested, 1016 (44.1%) and 131 (5.7%) yielded A(H1N1)pdm09 and seasonal influenza virus, respectively. Most specimens (42.0%) received were collected from patients <10 years old. Patients <20 years old were more likely than patients >50 years old to be infected with A(H1N1)pdm09 (odds ratio, 2.1; 95% confidence interval, 1.7-2.6; P < .01). Although phylogenetic analyses of A(H1N1)pdm09 suggested multiple introductions of the virus into Madagascar, no antigenic differences between A(H1N1)pdm09 viruses recovered in Madagascar and those that circulated worldwide were observed. CONCLUSIONS: The high proportion of respiratory specimens positive for A(H1N1)pdm09 is consistent with a widespread transmission of the pandemic in Madagascar. The age distribution of cases of A(H1N1)pdm09 infection suggests that children and young adults could be targeted for interventions that aim to reduce transmission during an influenza pandemic.


Subject(s)
Influenza A Virus, H1N1 Subtype/genetics , Influenza A Virus, H1N1 Subtype/isolation & purification , Influenza, Human/epidemiology , Influenza, Human/virology , Pandemics , Adolescent , Adult , Age Distribution , Aged , Child , Child, Preschool , Female , Genotype , Humans , Infant , Influenza A Virus, H1N1 Subtype/classification , Madagascar/epidemiology , Male , Middle Aged , Molecular Epidemiology , Molecular Sequence Data , Phylogeny , RNA, Viral/genetics , Sequence Analysis, DNA , Young Adult
12.
J Infect Dis ; 206 Suppl 1: S5-13, 2012 Dec 15.
Article in English | MEDLINE | ID: mdl-23169972

ABSTRACT

BACKGROUND: Although recent work has described the spatiotemporal diffusion of influenza viruses worldwide, comprehensive data on spatiotemporal patterns of influenza from the African continent and Madagascar are still lacking. METHODS: National Influenza Centers from 5 countries-Cameroon, Côte d'Ivoire, Madagascar, Niger, and Senegal--collected specimens from patients presenting with influenza-like illness who visited sentinel surveillance clinics during a 2-year period (2008-2009). Isolates were genetically and antigenically characterized. RESULTS: Overall, 8312 specimens were tested. Seasonal influenza A virus subtypes H1N1 and H3N2 and influenza B viruses were detected in 329, 689, and 148 specimens, respectively. In 2009, pandemic influenza A virus subtype H1N1 was detected in Madagascar most commonly (98.5% of cases). Influenza activity was either significant year-round or occurred during a specific period of the year in the African countries we evaluated. CONCLUSIONS: Our results demonstrate that, from Madagascar to Senegal, the epidemiologic and virologic characteristics of influenza viruses are diverse in terms of spatiotemporal circulation of the different virus types, subtypes, and strains. Our data highlight the importance of country-specific surveillance and of data and virus sharing, and they provide a rational basis to aid policy makers to develop strategies, such as vaccination at the right moment and with the right formulation, aimed at reducing the disease burden in Africa and Madagascar.


Subject(s)
Influenza, Human/epidemiology , Influenza, Human/virology , Orthomyxoviridae/classification , Orthomyxoviridae/isolation & purification , Sentinel Surveillance , Africa/epidemiology , Antigens, Viral/analysis , Genetic Variation , Humans , International Cooperation , Madagascar/epidemiology , Orthomyxoviridae/genetics , RNA, Viral/genetics , Time Factors , Topography, Medical
13.
PLoS One ; 7(5): e37067, 2012.
Article in English | MEDLINE | ID: mdl-22615893

ABSTRACT

BACKGROUND: The influenza A(H1N1)pdm09 virus has been a challenge for public health surveillance systems in all countries. In Antananarivo, the first imported case was reported on August 12, 2009. This work describes the spread of A(H1N1)pdm09 in Madagascar. METHODS: The diffusion of influenza A(H1N1)pdm09 in Madagascar was explored using notification data from a sentinel network. Clinical data were charted to identify peaks at each sentinel site and virological data was used to confirm viral circulation. RESULTS: From August 1, 2009 to February 28, 2010, 7,427 patients with influenza-like illness were reported. Most patients were aged 7 to 14 years. Laboratory tests confirmed infection with A(H1N1)pdm09 in 237 (33.2%) of 750 specimens. The incidence of patients differed between regions. By determining the epidemic peaks we traced the diffusion of the epidemic through locations and time in Madagascar. The first peak was detected during the epidemiological week 47-2009 in Antananarivo and the last one occurred in week 07-2010 in Tsiroanomandidy. CONCLUSION: Sentinel surveillance data can be used for describing epidemic trends, facilitating the development of interventions at the local level to mitigate disease spread and impact.


Subject(s)
Influenza A Virus, H1N1 Subtype/isolation & purification , Influenza, Human/epidemiology , Influenza, Human/virology , Adolescent , Adult , Child , Child, Preschool , Disease Outbreaks , Epidemics , Female , Humans , Incidence , Infant , Madagascar/epidemiology , Male , Public Health Surveillance/methods , Sentinel Surveillance , Young Adult
14.
Bull World Health Organ ; 90(5): 385-9, 2012 May 01.
Article in English | MEDLINE | ID: mdl-22589573

ABSTRACT

PROBLEM: The revision of the International Health Regulations (IHR) and the threat of influenza pandemics and other disease outbreaks with a major impact on developing countries have prompted bolstered surveillance capacity, particularly in low-resource settings. APPROACH: Surveillance tools with well-timed, validated data are necessary to strengthen disease surveillance. In 2007 Madagascar implemented a sentinel surveillance system for influenza-like illness (ILI) based on data collected from sentinel general practitioners. SETTING: Before 2007, Madagascar's disease surveillance was based on the passive collection and reporting of data aggregated weekly or monthly. The system did not allow for the early identification of outbreaks or unexpected increases in disease incidence. RELEVANT CHANGES: An innovative case reporting system based on the use of cell phones was launched in March 2007. Encrypted short message service, which costs less than 2 United States dollars per month per health centre, is now being used by sentinel general practitioners for the daily reporting of cases of fever and ILI seen in their practices. To validate the daily data, practitioners also report epidemiological and clinical data (e.g. new febrile patient's sex, age, visit date, symptoms) weekly to the epidemiologists on the research team using special patient forms. LESSONS LEARNT: Madagascar's sentinel ILI surveillance system represents the country's first nationwide "real-time" surveillance system. It has proved the feasibility of improving disease surveillance capacity through innovative systems despite resource constraints. This type of syndromic surveillance can detect unexpected increases in the incidence of ILI and other syndromic illnesses.


Subject(s)
Influenza, Human/epidemiology , Pandemics/prevention & control , Sentinel Surveillance , Text Messaging/instrumentation , Child , Confidence Intervals , Data Collection , Developing Countries , Disease Outbreaks , Female , Humans , Influenza Vaccines , Influenza, Human/diagnosis , Madagascar/epidemiology , Male , Public Health Practice , Risk Assessment
16.
PLoS Med ; 8(7): e1001053, 2011 Jul.
Article in English | MEDLINE | ID: mdl-21750667

ABSTRACT

BACKGROUND: Since the start of the 2009 influenza A pandemic (H1N1pdm), the World Health Organization and its member states have gathered information to characterize the clinical severity of H1N1pdm infection and to assist policy makers to determine risk groups for targeted control measures. METHODS AND FINDINGS: Data were collected on approximately 70,000 laboratory-confirmed hospitalized H1N1pdm patients, 9,700 patients admitted to intensive care units (ICUs), and 2,500 deaths reported between 1 April 2009 and 1 January 2010 from 19 countries or administrative regions--Argentina, Australia, Canada, Chile, China, France, Germany, Hong Kong SAR, Japan, Madagascar, Mexico, The Netherlands, New Zealand, Singapore, South Africa, Spain, Thailand, the United States, and the United Kingdom--to characterize and compare the distribution of risk factors among H1N1pdm patients at three levels of severity: hospitalizations, ICU admissions, and deaths. The median age of patients increased with severity of disease. The highest per capita risk of hospitalization was among patients <5 y and 5-14 y (relative risk [RR] = 3.3 and 3.2, respectively, compared to the general population), whereas the highest risk of death per capita was in the age groups 50-64 y and ≥65 y (RR = 1.5 and 1.6, respectively, compared to the general population). Similarly, the ratio of H1N1pdm deaths to hospitalizations increased with age and was the highest in the ≥65-y-old age group, indicating that while infection rates have been observed to be very low in the oldest age group, risk of death in those over the age of 64 y who became infected was higher than in younger groups. The proportion of H1N1pdm patients with one or more reported chronic conditions increased with severity (median = 31.1%, 52.3%, and 61.8% of hospitalized, ICU-admitted, and fatal H1N1pdm cases, respectively). With the exception of the risk factors asthma, pregnancy, and obesity, the proportion of patients with each risk factor increased with severity level. For all levels of severity, pregnant women in their third trimester consistently accounted for the majority of the total of pregnant women. Our findings suggest that morbid obesity might be a risk factor for ICU admission and fatal outcome (RR = 36.3). CONCLUSIONS: Our results demonstrate that risk factors for severe H1N1pdm infection are similar to those for seasonal influenza, with some notable differences, such as younger age groups and obesity, and reinforce the need to identify and protect groups at highest risk of severe outcomes. Please see later in the article for the Editors' Summary.


Subject(s)
Hospitalization/statistics & numerical data , Influenza A Virus, H1N1 Subtype/pathogenicity , Influenza, Human/mortality , Intensive Care Units/statistics & numerical data , Adolescent , Adult , Aged , Body Mass Index , Child , Child, Preschool , Chronic Disease/epidemiology , Chronic Disease/mortality , Data Interpretation, Statistical , Female , Global Health , Humans , Influenza, Human/epidemiology , Influenza, Human/virology , Male , Middle Aged , Odds Ratio , Pandemics/statistics & numerical data , Pregnancy , Prevalence , Risk Factors , Young Adult
17.
Proc Natl Acad Sci U S A ; 107(47): 20293-8, 2010 Nov 23.
Article in English | MEDLINE | ID: mdl-21059948

ABSTRACT

ATP-binding cassette (ABC) transporters are powered by a nucleotide-binding domain dimer that opens and closes during cycles of ATP hydrolysis. These domains consist of a RecA-like subdomain and an α-helical subdomain that is specific to the family. Many studies on isolated domains suggest that the helical subdomain rotates toward the RecA-like subdomain in response to ATP binding, moving the family signature motif into a favorable position to interact with the nucleotide across the dimer interface. Moreover, the transmembrane domains are docked into a cleft at the interface between these subdomains, suggesting a putative role of the rotation in interdomain communication. Electron paramagnetic resonance spectroscopy was used to study the dynamics of this rotation in the intact Escherichia coli maltose transporter MalFGK(2). This importer requires a periplasmic maltose-binding protein (MBP) that activates ATP hydrolysis by promoting the closure of the cassette dimer (MalK(2)). Whereas this rotation occurred during the transport cycle, it required not only trinucleotide, but also MBP, suggesting it is part of a global conformational change in the transporter. Interaction of AMP-PNP-Mg(2+) and a MBP that is locked in a closed conformation induced a transition from open MalK(2) to semiopen MalK(2) without significant subdomain rotation. Inward rotation of the helical subdomain and complete closure of MalK(2) therefore appear to be coupled to the reorientation of transmembrane helices and the opening of MBP, events that promote transfer of maltose into the transporter. After ATP hydrolysis, the helical subdomain rotates out as MalK(2) opens, resetting the transporter in an inward-facing conformation.


Subject(s)
ATP-Binding Cassette Transporters/genetics , Adenosine Triphosphate/metabolism , Escherichia coli Proteins/genetics , Models, Molecular , Protein Structure, Secondary/genetics , Protein Structure, Tertiary , ATP-Binding Cassette Transporters/isolation & purification , ATP-Binding Cassette Transporters/metabolism , Biological Transport/genetics , Dimerization , Electron Spin Resonance Spectroscopy , Escherichia coli Proteins/isolation & purification , Escherichia coli Proteins/metabolism , Hydrolysis , Mutagenesis, Site-Directed , Rotation , Spin Labels
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