Last data update: May 06, 2024. (Total: 46732 publications since 2009)
Records 1-30 (of 46 Records) |
Query Trace: Pollard W[original query] |
---|
Experimental study on the thermal protection enhancement of novel phase change material integrated structural firefighting gloves under high-heat exposures
Wang X , Zhao W , Pollard J , Xu SS . Case Stud Therm Eng 2024 56 Phase change material (PCM) has been widely studied for efficient thermal management. This work is the first holistic experimental research on the temperature control performance of PCM-integrated firefighters' gloves. The results showed that the thermal protection time could be extended by 2-5 times in the direct contact to hot object tests and around 1.5 times under the radiant/convective heat source tests when embedding a 1-mm-thick PCM layer in gloves. The PCM of melting point 68 °C showed the best thermal protection performance in all test conditions since it had the most efficient phase change function during the heating process. Considering the PCM location effect, the PCM with lower melting point (68 °C) showed better performance when located close to external environment (heat source) and the PCM with higher melting point (108 °C and 151 °C) showed better performance when located close to hand. The optimum PCM thickness would be in the range of 0.5-1.0 mm for both thermal protection improvement and hand dexterity purposes. In addition, the time for continuous temperature rises on the hand surface at post-heat exposure was longer when embedding PCM in firefighters’ gloves due to the stored latent heat in PCM. © 2024 The Authors |
Global diversity and antimicrobial resistance of typhoid fever pathogens: Insights from a meta-analysis of 13,000 Salmonella Typhi genomes
Carey ME , Dyson ZA , Ingle DJ , Amir A , Aworh MK , Chattaway MA , Chew KL , Crump JA , Feasey NA , Howden BP , Keddy KH , Maes M , Parry CM , Van Puyvelde S , Webb HE , Afolayan AO , Alexander AP , Anandan S , Andrews JR , Ashton PM , Basnyat B , Bavdekar A , Bogoch II , Clemens JD , da Silva KE , De A , de Ligt J , Diaz Guevara PL , Dolecek C , Dutta S , Ehlers MM , Francois Watkins L , Garrett DO , Godbole G , Gordon MA , Greenhill AR , Griffin C , Gupta M , Hendriksen RS , Heyderman RS , Hooda Y , Hormazabal JC , Ikhimiukor OO , Iqbal J , Jacob JJ , Jenkins C , Jinka DR , John J , Kang G , Kanteh A , Kapil A , Karkey A , Kariuki S , Kingsley RA , Koshy RM , Lauer AC , Levine MM , Lingegowda RK , Luby SP , Mackenzie GA , Mashe T , Msefula C , Mutreja A , Nagaraj G , Nagaraj S , Nair S , Naseri TK , Nimarota-Brown S , Njamkepo E , Okeke IN , Perumal SPB , Pollard AJ , Pragasam AK , Qadri F , Qamar FN , Rahman SIA , Rambocus SD , Rasko DA , Ray P , Robins-Browne R , Rongsen-Chandola T , Rutanga JP , Saha SK , Saha S , Saigal K , Sajib MSI , Seidman JC , Shakya J , Shamanna V , Shastri J , Shrestha R , Sia S , Sikorski MJ , Singh A , Smith AM , Tagg KA , Tamrakar D , Tanmoy AM , Thomas M , Thomas MS , Thomsen R , Thomson NR , Tupua S , Vaidya K , Valcanis M , Veeraraghavan B , Weill FX , Wright J , Dougan G , Argimón S , Keane JA , Aanensen DM , Baker S , Holt KE . Elife 2023 12 BACKGROUND: The Global Typhoid Genomics Consortium was established to bring together the typhoid research community to aggregate and analyse Salmonella enterica serovar Typhi (Typhi) genomic data to inform public health action. This analysis, which marks 22 years since the publication of the first Typhi genome, represents the largest Typhi genome sequence collection to date (n=13,000). METHODS: This is a meta-analysis of global genotype and antimicrobial resistance (AMR) determinants extracted from previously sequenced genome data and analysed using consistent methods implemented in open analysis platforms GenoTyphi and Pathogenwatch. RESULTS: Compared with previous global snapshots, the data highlight that genotype 4.3.1 (H58) has not spread beyond Asia and Eastern/Southern Africa; in other regions, distinct genotypes dominate and have independently evolved AMR. Data gaps remain in many parts of the world, and we show the potential of travel-associated sequences to provide informal 'sentinel' surveillance for such locations. The data indicate that ciprofloxacin non-susceptibility (>1 resistance determinant) is widespread across geographies and genotypes, with high-level ciprofloxacin resistance (≥3 determinants) reaching 20% prevalence in South Asia. Extensively drug-resistant (XDR) typhoid has become dominant in Pakistan (70% in 2020) but has not yet become established elsewhere. Ceftriaxone resistance has emerged in eight non-XDR genotypes, including a ciprofloxacin-resistant lineage (4.3.1.2.1) in India. Azithromycin resistance mutations were detected at low prevalence in South Asia, including in two common ciprofloxacin-resistant genotypes. CONCLUSIONS: The consortium's aim is to encourage continued data sharing and collaboration to monitor the emergence and global spread of AMR Typhi, and to inform decision-making around the introduction of typhoid conjugate vaccines (TCVs) and other prevention and control strategies. FUNDING: No specific funding was awarded for this meta-analysis. Coordinators were supported by fellowships from the European Union (ZAD received funding from the European Union's Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie grant agreement No 845681), the Wellcome Trust (SB, Wellcome Trust Senior Fellowship), and the National Health and Medical Research Council (DJI is supported by an NHMRC Investigator Grant [GNT1195210]). | Salmonella Typhi (Typhi) is a type of bacteria that causes typhoid fever. More than 110,000 people die from this disease each year, predominantly in areas of sub-Saharan Africa and South Asia with limited access to safe water and sanitation. Clinicians use antibiotics to treat typhoid fever, but scientists worry that the spread of antimicrobial-resistant Typhi could render the drugs ineffective, leading to increased typhoid fever mortality. The World Health Organization has prequalified two vaccines that are highly effective in preventing typhoid fever and may also help limit the emergence and spread of resistant Typhi. In low resource settings, public health officials must make difficult trade-off decisions about which new vaccines to introduce into already crowded immunization schedules. Understanding the local burden of antimicrobial-resistant Typhi and how it is spreading could help inform their actions. The Global Typhoid Genomics Consortium analyzed 13,000 Typhi genomes from 110 countries to provide a global overview of genetic diversity and antimicrobial-resistant patterns. The analysis showed great genetic diversity of the different strains between countries and regions. For example, the H58 Typhi variant, which is often drug-resistant, has spread rapidly through Asia and Eastern and Southern Africa, but is less common in other regions. However, distinct strains of other drug-resistant Typhi have emerged in other parts of the world. Resistance to the antibiotic ciprofloxacin was widespread and accounted for over 85% of cases in South Africa. Around 70% of Typhi from Pakistan were extensively drug-resistant in 2020, but these hard-to-treat variants have not yet become established elsewhere. Variants that are resistant to both ciprofloxacin and ceftriaxone have been identified, and azithromycin resistance has also appeared in several different variants across South Asia. The Consortium’s analyses provide valuable insights into the global distribution and transmission patterns of drug-resistant Typhi. Limited genetic data were available fromseveral regions, but data from travel-associated cases helped fill some regional gaps. These findings may help serve as a starting point for collective sharing and analyses of genetic data to inform local public health action. Funders need to provide ongoing supportto help fill global surveillance data gaps. | eng |
Global emergence and population dynamics of divergent serotype 3 CC180 pneumococci (preprint)
Azarian T , Mitchell PK , Georgieva M , Thompson CM , Ghouila A , Pollard AJ , von Gottberg A , du Plessis M , Antonio M , Kwambana-Adams BA , Clarke SC , Everett D , Cornick J , Sadowy E , Hryniewicz W , Skoczynska A , Moisi JC , McGee L , Beall B , Metcalf BJ , Breiman RF , Ho PL , Reid R , O'Brien KL , Gladstone RA , Bentley SD , Hanage WP . bioRxiv 2018 314880 Streptococcus pneumoniae serotype 3 remains a significant cause of morbidity and mortality worldwide, despite inclusion in the 13-valent pneumococcal conjugate vaccine (PCV13). Serotype 3 increased in carriage since the implementation of PCV13 in the United States, while invasive disease rates remain unchanged. We investigated the persistence of serotype 3 in carriage and disease, through genomic analyses of a global sample of 301 serotype 3 isolates of the Netherlands3–31 (PMEN31) clone CC180, combined with associated patient data and PCV utilization among countries of isolate collection. We assessed phenotypic variation between dominant clades in capsule charge (zeta potential), capsular polysaccharide shedding, and susceptibility to opsonophagocytic killing, which have previously been associated with carriage duration, invasiveness, and vaccine escape. We identify a recent shift in the CC180 population attributed to a lineage termed Clade II, which was estimated by Bayesian coalescent analysis to have first appeared in 1968 [95% HPD: 1939–1989] and increased in prevalence and effective population size thereafter. Clade II isolates are divergent from the pre-PCV13 serotype 3 population in non-capsular antigenic composition, competence, and antibiotic susceptibility, the last resulting from the acquisition of a Tn916-like conjugative transposon. Differences in recombination rates among clades correlated with variations in the ATP-binding subunit of Clp protease as well as amino acid substitutions in the comCDE operon. Opsonophagocytic killing assays elucidated the low observed efficacy of PCV13 against serotype 3. Variation in PCV13 use among sampled countries was not independently correlated with the CC180 population shift; therefore, genotypic and phenotypic differences in protein antigens and, in particular, antibiotic resistance may have contributed to the increase of Clade II. Our analysis emphasizes the need for routine, representative sampling of isolates from disperse geographic regions, including historically under-sampled areas. We also highlight the value of genomics in resolving antigenic and epidemiological variations within a serotype, which may have implications for future vaccine development.Author Summary Streptococcus pneumoniae is a leading cause of bacterial pneumoniae, meningitis, and otitis media. Despite inclusion in the most recent pneumococcal conjugate vaccine, PCV13, serotype 3 remains epidemiologically important globally. We investigated the persistence of serotype 3 using whole-genome sequencing data form 301 isolates collected among 24 countries from 1993–2014. Through phylogenetic analysis, we identified three distinct lineages within a single clonal complex, CC180, and found one has recently emerged and grown in prevalence. We then compared genomic difference among lineages as well as variations in pneumococcal vaccine use among sampled countries. We found that the recently emerged lineage, termed Clade II, has a higher prevalence of antibiotic resistance compared to other lineages, diverse surface protein antigens, and a higher rate of recombination, a process by which bacteria can uptake and incorporate genetic material from its surroundings. Differences in vaccine use among sampled countries did not appear to be associated with the emergence of Clade II. We highlight the need to routine, representative sampling of bacterial isolates from diverse geographic areas and show the utility of genomic data in resolving epidemiological differences within a pathogen population. |
Developing high-resolution population and settlement data for impactful malaria interventions in Zambia
Borkovska O , Pollard D , Hamainza B , Kooma E , Renn S , Schmidt J , Engin H , Heaton M , Miller JM , Psychas P , Riley C , Martin A , Nyirenda J , Bwalya F , Winters A , Sobel C . J Environ Public Health 2022 2022 2941013 Foundational high-resolution geospatial data products for population, settlements, infrastructure, and boundaries may greatly enhance the efficient planning of resource allocation during health sector interventions. To ensure the relevance and sustainability of such products, government partners must be involved from the beginning in their creation, improvement, and/or management, so they can be successfully applied to public health campaigns, such as malaria control and prevention. As an example, Zambia had an ambitious strategy of reaching the entire population with malaria vector control campaigns by late 2020 or early 2021, but they lacked the requisite accurate and up-to-date data on infrastructure and population distribution. To address this gap, the Geo-Referenced Infrastructure and Demographic Data for Development (GRID3) program, Akros, and other partners developed maps and planning templates to aid Zambia's National Malaria Elimination Program (NMEP) in operationalizing its strategy. |
Emergence of a multidrug-resistant and virulent Streptococcus pneumoniae lineage mediates serotype replacement after PCV13: an international whole-genome sequencing study.
Lo SW , Mellor K , Cohen R , Alonso AR , Belman S , Kumar N , Hawkins PA , Gladstone RA , von Gottberg A , Veeraraghavan B , Ravikumar KL , Kandasamy R , Pollard SAJ , Saha SK , Bigogo G , Antonio M , Kwambana-Adams B , Mirza S , Shakoor S , Nisar I , Cornick JE , Lehmann D , Ford RL , Sigauque B , Turner P , Moïsi J , Obaro SK , Dagan R , Diawara I , SkoczyĆska A , Wang H , Carter PE , Klugman KP , Rodgers G , Breiman RF , McGee L , Bentley SD , Almagro CM , Varon E . Lancet Microbe 2022 3 (10) e735-e743 BACKGROUND: Serotype 24F is one of the emerging pneumococcal serotypes after the introduction of pneumococcal conjugate vaccine (PCV). We aimed to identify lineages driving the increase of serotype 24F in France and place these findings into a global context. METHODS: Whole-genome sequencing was performed on a collection of serotype 24F pneumococci from asymptomatic colonisation (n=229) and invasive disease (n=190) isolates among individuals younger than 18 years in France, from 2003 to 2018. To provide a global context, we included an additional collection of 24F isolates in the Global Pneumococcal Sequencing (GPS) project database for analysis. A Global Pneumococcal Sequence Cluster (GPSC) and a clonal complex (CC) were assigned to each genome. Phylogenetic, evolutionary, and spatiotemporal analysis were conducted using the same 24F collection and supplemented with a global collection of genomes belonging to the lineage of interest from the GPS project database (n=25 590). FINDINGS: Serotype 24F was identified in numerous countries mainly due to the clonal spread of three lineages: GPSC10 (CC230), GPSC16 (CC156), and GPSC206 (CC7701). GPSC10 was the only multidrug-resistant lineage. GPSC10 drove the increase in 24F in France and had high invasive disease potential. The international dataset of GPSC10 (n=888) revealed that this lineage expressed 16 other serotypes, with only six included in 13-valent PCV (PCV13). All serotype 24F isolates were clustered in a single clade within the GPSC10 phylogeny and long-range transmissions were detected from Europe to other continents. Spatiotemporal analysis showed GPSC10-24F took 3-5 years to spread across France and a rapid change of serotype composition from PCV13 serotype 19A to 24F during the introduction of PCV13 was observed in neighbouring country Spain. INTERPRETATION: Our work reveals that GPSC10 alone is a challenge for serotype-based vaccine strategy. More systematic investigation to identify lineages like GPSC10 will better inform and improve next-generation preventive strategies against pneumococcal diseases. FUNDING: Bill & Melinda Gates Foundation, Wellcome Sanger Institute, and the US Centers for Disease Control and Prevention. |
Effect of childhood vaccination and antibiotic use on pneumococcal populations and genome-wide associations with disease among children in Nepal: an observational study.
Kandasamy R , Lo S , Gurung M , Carter MJ , Gladstone R , Lees J , Shrestha S , Thorson S , Bijukchhe S , Gautam MC , Shrestha R , Gurung S , Khadka B , McGee L , Breiman RF , Murdoch DR , Kelly DF , Shrestha S , Bentley SD , Pollard AJ . Lancet Microbe 2022 3 (7) e503-e511 BACKGROUND: Pneumococcal disease is a leading cause of bacterial pneumonia and invasive bacterial disease among children globally. The reason some strains of pneumococci are more likely to cause disease, and how interventions such as vaccines and antibiotics affect pneumococcal strains is poorly understood. We aimed to identify genetic regions under selective pressure and those associated with disease through the analysis of pneumococcal whole-genome sequences. METHODS: Whole-genome sequencing was performed on pneumococcal isolates collected between January, 2005, and May, 2018, in Kathmandu, Nepal, which included programmatic ten-valent pneumococcal conjugate vaccine (PCV10) introduction in 2015. Isolates were from three distinct cohorts: nasopharyngeal swabs of healthy community-based children, nasopharyngeal swabs of children admitted to hospital with pneumonia, and sterile-site cultures from children admitted to hospital. Across these cohorts we examined serotype distribution, antibiotic resistance, strain distribution, and regions of recombination to determine genes that were undergoing diversifying selection. Genome-wide association studies comparing pneumonia and sterile-site isolates with healthy carriage were used to determine novel variants associated with disease. FINDINGS: After programmatic introduction of PCV10, there was a decline in vaccine covered serotypes; however, strains that had expressed these serotypes continued to exist in the post-PCV population. We identified GPSC9 to be a strain of concern due to its high prevalence in disease, multidrug resistance, and ability to switch to an unencapsulated phenotype via insertion of virulence factor pspC into the cps locus. Antibiotic resistance loci to co-trimoxazole were found to be prevalent (pre-PCV10 78% vs post-PCV10 81%; p=0·27) and increasingly prevalent to penicillin (pre-PCV10 15% vs post-PCV10 32%; p<0·0001). Regions with multiple recombinations were identified spanning the surface protein virulence factors pspA and pspC and antibiotic targets pbpX, folA, folC, folE, and folP. Furthermore, we identified variants in lacE2 to be strongly associated with isolates from children with pneumonia and PRIP to be strongly associated with isolates from sterile sites. INTERPRETATION: Our work highlights the effect of pneumococcal conjugate vaccines, antibiotics, and host-pathogen interaction in pneumococcal variation, and the pathogen's capability of adapting to these factors at both population-wide and strain-specific levels. Ongoing surveillance of disease-associated strains and further investigation of lacE2 and PRIP as serotype-independent targets for therapeutic interventions is required. FUNDING: Gavi, The Vaccine Alliance; WHO; Bill & Melinda Gates Foundation; Wellcome Sanger Institute; and US Centers for Disease Control and Prevention. |
The necessity for improved hand and finger protection in mining
Heberger JR , Nasarwanji MF , Pollard JP , Kocher LM . Min Metall Explor 2022 39 (2) 507-520 Injuries associated with hands and fingers are highly prevalent in mining and identifying factors associated with these injuries are critical in developing prevention efforts. This study identifies nonfatal injury incidence rates, nature of injury, work activities, glove usage, and sources of hand and finger injuries in the U.S. mining industry, as reported to the Mine Safety and Health Administration (MSHA) from 2011 - 2017. Hand and finger injuries occur at a rate of 6.53 per 1000 full-time employees, which is nearly double the rate of the next highest affected body part, the back. Most of the hand and finger injuries were classified as cuts/lacerations/punctures (53%) followed by bone fractures/chips (26%). Materials handling and maintenance/repair were common activities at the time of the incident with miscellaneous metals (pipe, wire, guarding) and hand tools as the primary sources of hand and finger injury. Although the information on glove use was limited, leather gloves were most often worn when an injury occurred. When worn, gloves were found to contribute to 20% of the injuries, indicating their potential to protect the hands, but also potentially put the hands at risk. Further research is necessary to determine performance requirements for gloves used in mining operations, specifically those offering cut and puncture resistance. © 2022, This is a U.S. government work and not under copyright protection in the U.S.; foreign copyright protection may apply. |
Exploring Structural Uncertainty and Impact of Health State Utility Values on Lifetime Outcomes in Diabetes Economic Simulation Models: Findings from the Ninth Mount Hood Diabetes Quality-of-Life Challenge
Tew M , Willis M , Asseburg C , Bennett H , Brennan A , Feenstra T , Gahn J , Gray A , Heathcote L , Herman WH , Isaman D , Kuo S , Lamotte M , Leal J , McEwan P , Nilsson A , Palmer AJ , Patel R , Pollard D , Ramos M , Sailer F , Schramm W , Shao H , Shi L , Si L , Smolen HJ , Thomas C , Tran-Duy A , Yang C , Ye W , Yu X , Zhang P , Clarke P . Med Decis Making 2021 42 (5) 272989x211065479 BACKGROUND: Structural uncertainty can affect model-based economic simulation estimates and study conclusions. Unfortunately, unlike parameter uncertainty, relatively little is known about its magnitude of impact on life-years (LYs) and quality-adjusted life-years (QALYs) in modeling of diabetes. We leveraged the Mount Hood Diabetes Challenge Network, a biennial conference attended by international diabetes modeling groups, to assess structural uncertainty in simulating QALYs in type 2 diabetes simulation models. METHODS: Eleven type 2 diabetes simulation modeling groups participated in the 9th Mount Hood Diabetes Challenge. Modeling groups simulated 5 diabetes-related intervention profiles using predefined baseline characteristics and a standard utility value set for diabetes-related complications. LYs and QALYs were reported. Simulations were repeated using lower and upper limits of the 95% confidence intervals of utility inputs. Changes in LYs and QALYs from tested interventions were compared across models. Additional analyses were conducted postchallenge to investigate drivers of cross-model differences. RESULTS: Substantial cross-model variability in incremental LYs and QALYs was observed, particularly for HbA1c and body mass index (BMI) intervention profiles. For a 0.5%-point permanent HbA1c reduction, LY gains ranged from 0.050 to 0.750. For a 1-unit permanent BMI reduction, incremental QALYs varied from a small decrease in QALYs (-0.024) to an increase of 0.203. Changes in utility values of health states had a much smaller impact (to the hundredth of a decimal place) on incremental QALYs. Microsimulation models were found to generate a mean of 3.41 more LYs than cohort simulation models (P = 0.049). CONCLUSIONS: Variations in utility values contribute to a lesser extent than uncertainty captured as structural uncertainty. These findings reinforce the importance of assessing structural uncertainty thoroughly because the choice of model (or models) can influence study results, which can serve as evidence for resource allocation decisions.HighlightsThe findings indicate substantial cross-model variability in QALY predictions for a standardized set of simulation scenarios and is considerably larger than within model variability to alternative health state utility values (e.g., lower and upper limits of the 95% confidence intervals of utility inputs).There is a need to understand and assess structural uncertainty, as the choice of model to inform resource allocation decisions can matter more than the choice of health state utility values. |
A taxonomy of surface mining slip, trip, and fall hazards as a guide to research and practice
Nasarwanji MF , Dempsey PG , Pollard J , Whitson A , Kocher L . Appl Ergon 2021 97 103542 Slips, trips, and falls (STFs) are the second leading cause of non-fatal injuries and can lead to fatal incidents in the mining industry. Hazard identification is an essential first step in remediating STF hazards and creating a safer work environment. Previous research has identified industry-specific risk factors for STFs, evaluated exposures to those risk factors, and developed taxonomies of the hazards for the construction and farming sectors. In comparison, ErgoMine-a mobile device application-based ergonomics audit tool-is the only systematic evaluation tool that covers STF hazards in the mining industry. However, ErgoMine was not specifically developed to address STF hazards. This paper describes the development of a taxonomy that helps identify STF hazards at surface mining sites and provides recommendations to address these hazards to inform future evaluation tools. The objective was to develop a taxonomy that was self-explanatory, observable, repeatable, and solution oriented. In addition to current regulations, standards and guidelines were used to develop the taxonomy to ensure the focus was beyond basic compliance. A detailed description of how the STF hazard taxonomy was created for walkways, stairways, and fixed ladders is provided, along with two specific applications of its use. The STF hazard taxonomy can be used to develop tools like checklists and ergonomics audits to identify and remediate slip, trip, and fall hazards at surface mining facilities, thereby improving worker safety. |
TIPICO X: report of the 10th interactive infectious disease workshop on infectious diseases and vaccines
Rivero-Calle I , Gómez-Rial J , Bont L , Gessner BD , Kohn M , Dagan R , Payne DC , Bruni L , Pollard AJ , García-Sastre A , Faustman DL , Osterhaus A , Butler R , Giménez Sánchez F , Álvarez F , Kaforou M , Bello X , Martinón-Torres F . Hum Vaccin Immunother 2021 17 (3) 759-772 TIPICO is an expert meeting and workshop that aims to provide the most recent evidence in the field of infectious diseases and vaccination. The 10th Interactive Infectious Disease TIPICO workshop took place in Santiago de Compostela, Spain, on November 21-22, 2019. Cutting-edge advances in vaccination against respiratory syncytial virus, Streptococcus pneumoniae, rotavirus, human papillomavirus, Neisseria meningitidis, influenza virus, and Salmonella Typhi were discussed. Furthermore, heterologous vaccine effects were updated, including the use of Bacillus Calmette-Guérin (BCG) vaccine as potential treatment for type 1 diabetes. Finally, the workshop also included presentations and discussion on emergent virus and zoonoses, vaccine resilience, building and sustaining confidence in vaccination, approaches to vaccine decision-making, pros and cons of compulsory vaccination, the latest advances in decoding infectious diseases by RNA gene signatures, and the application of big data approaches. |
Vaccine safety issues at the turn of the 21st century
Conklin L , Hviid A , Orenstein WA , Pollard AJ , Wharton M , Zuber P . BMJ Glob Health 2021 6 Global gains in vaccination coverage during the early 21st century have been threatened by the emergence of antivaccination groups that have questioned the effectiveness of vaccines to generate public distrust of vaccines and immunisation programmes. This manuscript summarises six key topics that have been at the centre of global discussions on vaccine safety during the early 21st century: thiomersal in multi-dose non-live vaccines, aluminium adjuvants used with several non-live vaccines, autism and auto-immune conditions as possible consequences of vaccination, a risk of immune overload with increasing numbers of vaccinations, and detrimental non-specific effects (NSEs) of vaccination. For each topic, we describe the hypothesis behind the public concern, the evidence reviewed by the WHO's Global Advisory Committee for Vaccine Safety (GACVS) during 1999-2019, and any significant new data that has emerged since GACVS conclusions were made. Although the scientific evidence on these issues overwhelmingly supports the safety of vaccines, communication messages to caregivers and providers need to condense and convey scientific information in an appropriate way to address concerns contributing to vaccine distrust. In addition, there is need for further studies specifically designed to address both positive and negative NSE of vaccination. The role of GACVS will be increasingly important in evaluating the evidence and engaging the global community in promoting and assuring the safety of vaccines in the decades to come as we move into an era in which we use new vaccination platforms, antigens and formulations. |
Yersinia enterocolitica Outbreak Associated with Pasteurized Milk
Gruber JF , Morris S , Warren KA , Kline KE , Schroeder B , Dettinger L , Husband B , Pollard K , Davis C , Miller J , Weltman A , Mattioli M , Ray L , Tarr C , Longenberger AH . Foodborne Pathog Dis 2021 18 (7) 448-454 In July 2019, we investigated a cluster of Yersinia enterocolitica cases affecting a youth summer camp and nearby community in northeastern Pennsylvania. After initial telephone interviews with camp owners and community members, we identified pasteurized milk from a small dairy conducting on-site pasteurization, Dairy A, as a shared exposure. We conducted site visits at the camp and Dairy A where we collected milk and other samples. Samples were cultured for Y. enterocolitica. Clinical and nonclinical isolates were compared using molecular subtyping. We performed case finding, conducted telephone interviews for community cases, and conducted a cohort study among adult camp staff by administering an online questionnaire. In total, we identified 109 Y. enterocolitica cases. Consumption of Dairy A milk was known for 37 (34%); of these, Dairy A milk was consumed by 31 (84%). Dairy A had shipped 214 gallons of pasteurized milk in 5 weekly shipments to the camp by mid-July. Dairy A milk was the only shared exposure identified between the camp and community. Y. enterocolitica was isolated from Dairy A unpasteurized milk samples. Five clinical isolates from camp members, two clinical isolates from community members, and nine isolates from unpasteurized milk were indistinguishable by whole-genome sequencing. The risk for yersinosis among camp staff who drank Dairy A milk was 5.3 times the risk for those who did not (95% confidence interval: 1.6-17.3). Because Dairy A only sold pasteurized milk, pasteurized milk was considered the outbreak source. We recommend governmental agencies and small dairies conducting on-site pasteurization collaborate to develop outbreak prevention strategies. |
Editorial: Immune Mechanisms in the Pathologic Response to Particles, Fibers, and Nanomaterials
Ma Q , Pollard KM , Brown JM , Italiani P , Moghimi SM . Front Immunol 2021 12 665810 It may come as a surprise that a Research Topic in Frontiers in Immunology is devoted to “Immune mechanisms” in the pathologic response to “particles, fibers, and nanomaterials,” a large group of natural and man-made particulates with dimensions in micro and nano ranges. Unlike pathogens, many particulate materials do not possess apparent antigenic structures and are assumed to be non-immunogenic. But because of their small size and airborne propensity, inhaled particulates can penetrate deep into the lung and pleura to cause inflammation, fibrosis, and cancer, exemplified by silicosis, asbestosis, and mesothelioma that are progressive and have high mortality rates (1, 2). Notwithstanding, the role of immune responses in the pathogenesis of particulate-induced diseases has gained increasing attention. A plethora of studies have shown that particulates activate various immune cells to promote physiological responses to particulate deposition and, under pathological conditions, development of fibrosis, malignancy, and autoimmunity (3, 4). The past two decades have also witnessed rapid advancement of nanotechnology and commercialization of nanomaterials, raising concerns on their possible adverse immune effects in exposed individuals (5–7). Understanding the interactions between particulates and immune functions has emerged as a new frontier for researchers in immunology, toxicology, and nanoscience. This Research Topic discusses recent trends in particle immunotoxicology with focus on pathologic immune effects of particulates and mechanisms mediating particle-immune interactions. |
Evaluating the ability of economic models of diabetes to simulate new cardiovascular outcomes trials: A report on the Ninth Mount Hood Diabetes Challenge
Si L , Willis MS , Asseburg C , Nilsson A , Tew M , Clarke PM , Lamotte M , Ramos M , Shao H , Shi L , Zhang P , McEwan P , Ye W , Herman WH , Kuo S , Isaman DJ , Schramm W , Sailer F , Brennan A , Pollard D , Smolen HJ , Leal J , Gray A , Patel R , Feenstra T , Palmer AJ . Value Health 2020 23 (9) 1163-1170 Objectives: The cardiovascular outcomes challenge examined the predictive accuracy of 10 diabetes models in estimating hard outcomes in 2 recent cardiovascular outcomes trials (CVOTs) and whether recalibration can be used to improve replication. Methods: Participating groups were asked to reproduce the results of the Empagliflozin Cardiovascular Outcome Event Trial in Type 2 Diabetes Mellitus Patients (EMPA-REG OUTCOME) and the Canagliflozin Cardiovascular Assessment Study (CANVAS) Program. Calibration was performed and additional analyses assessed model ability to replicate absolute event rates, hazard ratios (HRs), and the generalizability of calibration across CVOTs within a drug class. Results: Ten groups submitted results. Models underestimated treatment effects (ie, HRs) using uncalibrated models for both trials. Calibration to the placebo arm of EMPA-REG OUTCOME greatly improved the prediction of event rates in the placebo, but less so in the active comparator arm. Calibrating to both arms of EMPA-REG OUTCOME individually enabled replication of the observed outcomes. Using EMPA-REG OUTCOME–calibrated models to predict CANVAS Program outcomes was an improvement over uncalibrated models but failed to capture treatment effects adequately. Applying canagliflozin HRs directly provided the best fit. Conclusions: The Ninth Mount Hood Diabetes Challenge demonstrated that commonly used risk equations were generally unable to capture recent CVOT treatment effects but that calibration of the risk equations can improve predictive accuracy. Although calibration serves as a practical approach to improve predictive accuracy for CVOT outcomes, it does not extrapolate generally to other settings, time horizons, and comparators. New methods and/or new risk equations for capturing these CV benefits are needed. |
The Surveillance for Enteric Fever in Asia Project (SEAP), Severe Typhoid Fever Surveillance in Africa (SETA), Surveillance of Enteric Fever in India (SEFI), and Strategic Typhoid Alliance Across Africa and Asia (STRATAA) Population-based Enteric Fever Studies: A review of methodological similarities and differences
Carey ME , MacWright WR , Im J , Meiring JE , Gibani MM , Park SE , Longley A , Jeon HJ , Hemlock C , Yu AT , Soura A , Aiemjoy K , Owusu-Dabo E , Terferi M , Islam S , Lunguya O , Jacobs J , Gordon M , Dolecek C , Baker S , Pitzer VE , Yousafzai MT , Tonks S , Clemens JD , Date K , Qadri F , Heyderman RS , Saha SK , Basnyat B , Okeke IN , Qamar FN , Voysey M , Luby S , Kang G , Andrews J , Pollard AJ , John J , Garrett D , Marks F . Clin Infect Dis 2020 71 S102-s110 Building on previous multicountry surveillance studies of typhoid and others salmonelloses such as the Diseases of the Most Impoverished program and the Typhoid Surveillance in Africa Project, several ongoing blood culture surveillance studies are generating important data about incidence, severity, transmission, and clinical features of invasive Salmonella infections in sub-Saharan Africa and South Asia. These studies are also characterizing drug resistance patterns in their respective study sites. Each study answers a different set of research questions and employs slightly different methodologies, and the geographies under surveillance differ in size, population density, physician practices, access to healthcare facilities, and access to microbiologically safe water and improved sanitation. These differences in part reflect the heterogeneity of the epidemiology of invasive salmonellosis globally, and thus enable generation of data that are useful to policymakers in decision-making for the introduction of typhoid conjugate vaccines (TCVs). Moreover, each study is evaluating the large-scale deployment of TCVs, and may ultimately be used to assess post-introduction vaccine impact. The data generated by these studies will also be used to refine global disease burden estimates. It is important to ensure that lessons learned from these studies not only inform vaccination policy, but also are incorporated into sustainable, low-cost, integrated vaccine-preventable disease surveillance systems. |
Effects of metatarsal work boots on gait during level and inclined walking
Kocher LM , Pollard JP , Whitson AE , Nasarwanji MF . J Appl Biomech 2020 1-8 Footwear plays an important role in worker safety. Work boots with safety toes are often utilized at mine sites to protect workers from hazards. Increasingly, mining operations require metatarsal guards in addition to safety toe protection in boots. While these guards provide additional protection, the impact of metatarsal guards on gait are unknown. This study aimed to measure the effects of 4 safety work boots, steel toe, and steel toe with metatarsal protection in wader- and hiker-style boots, on level and inclined walking gait characteristics, during ascent and descent. A total of 10 participants completed this study. A motion capture system measured kinematics that allowed for the calculation of key gait parameters. Results indicated that gait parameters changed due to incline, similar to previous literature. Wader-style work boots reduced ankle range of motion when ascending an incline. Hip, knee, and ankle ranges of motion were also reduced during descent for this style of boot. Wader-style boots with metatarsal guards led to the smallest ankle range of motion when descending an inclined walkway. From these results, it is likely that boot style affects gait parameters and may impact a miner's risk for slips, trips, or falls. |
Leveraging risk maps of malaria vector abundance to guide control efforts reduces malaria incidence in Eastern Province, Zambia
Larsen DA , Martin A , Pollard D , Nielsen CF , Hamainza B , Burns M , Stevenson J , Winters A . Sci Rep 2020 10 (1) 10307 Although transmission of malaria and other mosquito-borne diseases is geographically heterogeneous, in sub-Saharan Africa risk maps are rarely used to determine which communities receive vector control interventions. We compared outcomes in areas receiving different indoor residual spray (IRS) strategies in Eastern Province, Zambia: (1) concentrating IRS interventions within a geographical area, (2) prioritizing communities to receive IRS based on predicted probabilities of Anopheles funestus, and (3) prioritizing communities to receive IRS based on observed malaria incidence at nearby health centers. Here we show that the use of predicted probabilities of An. funestus to guide IRS implementation saw the largest decrease in malaria incidence at health centers, a 13% reduction (95% confidence interval = 5-21%) compared to concentrating IRS geographically and a 37% reduction (95% confidence interval = 30-44%) compared to targeting IRS based on health facility incidence. These results suggest that vector control programs could produce better outcomes by prioritizing IRS according to malaria-vector risk maps. |
A General Framework to Test and Evaluate Filtering Facepiece Respirators Considered for Crisis Capacity Use as a Strategy to Optimize Supply.
Yoon KN , Greenawald LA , Rottach DR , Pollard JP , Yorio PL . J Int Soc Respir Prot 2020 36 (1) 36-51 During a public health emergency, respirator shortages can have a profound impact on the national response, such as for the current coronavirus disease 2019 (COVID-19) pandemic. Due to a severe shortage of respirators (particularly filtering facepiece respirators [FFRs]), there may be contexts in which understanding the performance of FFRs that are approved for use as part of a crisis capacity strategy is desired. This includes FFRs that are not covered under the National Institute for Occupational Safety and Health (NIOSH) Respirator Approval Program because they have been stored past their designated shelf life, have been decontaminated, or are approved by international certification bodies other than NIOSH. The purpose of this document is to provide a general framework to assess the performance of FFRs that are only being used as a crisis capacity strategy. The intended audience are those who are responsible for managing large amounts of FFRs. This framework includes a four-step process consisting of: 1) defining the population of FFRs to be sampled; 2) providing sampling strategy options; 3) inspecting and testing the sampled units; and 4) evaluating the results. In addition to the four-step process, we provide an example of how NIOSH recently evaluated the quality of FFRs sampled from ten U.S. stockpiles. |
Visualizing variation within Global Pneumococcal Sequence Clusters (GPSCs) and country population snapshots to contextualize pneumococcal isolates.
Gladstone RA , Lo SW , Goater R , Yeats C , Taylor B , Hadfield J , Lees JA , Croucher NJ , van Tonder AJ , Bentley LJ , Quah FX , Blaschke AJ , Pershing NL , Byington CL , Balaji V , Hryniewicz W , Sigauque B , Ravikumar KL , Almeida SCG , Ochoa TJ , Ho PL , du Plessis M , Ndlangisa KM , Cornick JE , Kwambana-Adams B , Benisty R , Nzenze SA , Madhi SA , Hawkins PA , Pollard AJ , Everett DB , Antonio M , Dagan R , Klugman KP , von Gottberg A , Metcalf BJ , Li Y , Beall BW , McGee L , Breiman RF , Aanensen DM , Bentley SD . Microb Genom 2020 6 (5) Knowledge of pneumococcal lineages, their geographic distribution and antibiotic resistance patterns, can give insights into global pneumococcal disease. We provide interactive bioinformatic outputs to explore such topics, aiming to increase dissemination of genomic insights to the wider community, without the need for specialist training. We prepared 12 country-specific phylogenetic snapshots, and international phylogenetic snapshots of 73 common Global Pneumococcal Sequence Clusters (GPSCs) previously defined using PopPUNK, and present them in Microreact. Gene presence and absence defined using Roary, and recombination profiles derived from Gubbins are presented in Phandango for each GPSC. Temporal phylogenetic signal was assessed for each GPSC using BactDating. We provide examples of how such resources can be used. In our example use of a country-specific phylogenetic snapshot we determined that serotype 14 was observed in nine unrelated genetic backgrounds in South Africa. The international phylogenetic snapshot of GPSC9, in which most serotype 14 isolates from South Africa were observed, highlights that there were three independent sub-clusters represented by South African serotype 14 isolates. We estimated from the GPSC9-dated tree that the sub-clusters were each established in South Africa during the 1980s. We show how recombination plots allowed the identification of a 20 kb recombination spanning the capsular polysaccharide locus within GPSC97. This was consistent with a switch from serotype 6A to 19A estimated to have occured in the 1990s from the GPSC97-dated tree. Plots of gene presence/absence of resistance genes (tet, erm, cat) across the GPSC23 phylogeny were consistent with acquisition of a composite transposon. We estimated from the GPSC23-dated tree that the acquisition occurred between 1953 and 1975. Finally, we demonstrate the assignment of GPSC31 to 17 externally generated pneumococcal serotype 1 assemblies from Utah via Pathogenwatch. Most of the Utah isolates clustered within GPSC31 in a USA-specific clade with the most recent common ancestor estimated between 1958 and 1981. The resources we have provided can be used to explore to data, test hypothesis and generate new hypotheses. The accessible assignment of GPSCs allows others to contextualize their own collections beyond the data presented here. |
Analysis of fall-related imminent danger orders in the metal/nonmetal mining sector
Hrica JK , Eiter BM , Pollard JP , Kocher LM , Nasarwanji M . Min Metall Explor 2020 37 (2) 619-630 Within the metal/nonmetal mining sector, fall-related incidents account for a large proportion of fatal and non-fatal injuries. However, the events and contributing factors leading up to these incidents have not been fully investigated. To help provide a clearer picture of these factors, an analysis of imminent danger orders issued by the Mine Safety and Health Administration (MSHA) between 2010 and 2017 at both surface and underground metal/nonmetal mine sites revealed that most orders are associated with fall risks. Of these cases, 84% involved the workers not using fall protection, fall protection not being provided, or the improper use of fall protection. Fall risks for workers most frequently occurred when standing on mobile equipment, performing maintenance and repairs on plant equipment, or working near highwalls. In most cases, a single, basic, corrective action (e.g., using fall protection) would have allowed workers to perform the task safely. Overall, these findings suggest that a systematic approach is needed to identify, eliminate, and prevent imminent danger situations. Furthermore, to protect mineworkers from falls from height, frequently performed tasks requiring fall protection should be redesigned to eliminate the reliance on personal fall protection. |
The science of vaccine safety: Summary of meeting at Wellcome Trust
Plotkin SA , Offit PA , DeStefano F , Larson HJ , Arora NK , Zuber PLF , Fombonne E , Sejvar J , Lambert PH , Hviid A , Halsey N , Garcon N , Peden K , Pollard AJ , Markowitz LE , Glanz J . Vaccine 2020 38 (8) 1869-1880 Vaccines are everywhere hugely successful but are also under attack. The reason for the latter is the perception by some people that vaccines are unsafe. However that may be, vaccine safety, life any other scientific subject, must be constantly studied. It was from this point of view that a meeting was organized at the Wellcome Trust in London in May 2019 to assess some aspects of vaccine safety as subjects for scientific study. The objective of the meeting was to assess what is known beyond reasonable doubt and conversely what areas need additional studies. Although the meeting could not cover all aspects of vaccine safety science, many of the most important issues were addressed by a group of about 30 experts to determine what is already known and what additional studies are merited to assess the safety of the vaccines currently in use. The meeting began with reviews of the current situation in different parts of the world, followed by reviews of specific controversial areas, including the incidence of certain conditions after vaccination and the safety of certain vaccine components. Lastly, information about the human papillomavirus vaccine was considered because its safety has been particularly challenged by vaccine opponents. The following is a summary of the meeting findings. In addition to this summary, the meeting organizers will explore opportunities to perform studies that would enlarge knowledge of vaccine safety. |
Operators' views of mobile equipment ingress and egress safety
Pollard J , Kosmoski C , Porter WL , Kocher L , Whitson A , Nasarwanji M . Int J Ind Ergon 2019 72 272-280 A large proportion of non-fatal slips, trips, and falls (STFs) at surface mining facilities are associated with mobile equipment. Ingress and egress from mobile equipment can pose a fall risk to mobile equipment operators. The objective of this study was to determine mobile equipment operators' views of STF risks from mobile equipment, and to ascertain what factors, tasks, and conditions they perceive as contributing to these risks. A thematic analysis of 23 individual interviews and 2 group interviews was conducted, with 10 overarching themes identified from the transcripts. Mobile equipment operators indicated that being unable to see their feet or the ladder rungs during descent and the presence of contaminants on the ladders caused by normal operation make egress more dangerous than ingress. The flexible rails and high heights of the lower rungs identified over 40 years ago as issues for mobile equipment operators still pose a perceived STF risk. Further, the requirements of routine maintenance tasks such as oil and filter changes, greasing, and cleaning windows pose fall risks due to inadequate access and the need to carry supplies up and down equipment ladders. In addition to the mobile equipment, hazardous ground conditions and insufficient lighting were found to be key issues around the mobile equipment and in parking areas. The findings of this work indicate that mobile equipment operators feel at risk for STFs due to the design and condition of their equipment, and would like to see ladders replaced with safer stairways as the primary ingress/egress system. |
The role of immune correlates of protection on the pathway to licensure, policy decision and use of group B Streptococcus vaccines for maternal immunization: considerations from World Health Organization consultations
Vekemans J , Crofts J , Baker CJ , Goldblatt D , Heath PT , Madhi SA , Le Doare K , Andrews N , Pollard AJ , Saha SK , Schrag SJ , Smith PG , Kaslow DC . Vaccine 2019 37 (24) 3190-3198 The development of a group B Streptococcus (GBS) vaccine for maternal immunization constitutes a global public health priority, to prevent GBS-associated early life invasive disease, stillbirth, premature birth, maternal sepsis, adverse neurodevelopmental consequences, and to reduce perinatal antibiotic use. Sample size requirements for the conduct of a randomized placebo-controlled trial to assess vaccine efficacy against the most relevant clinical endpoints, under conditions of appropriate ethical standards of care, constitute a significant obstacle on the pathway to vaccine availability. Alternatively, indirect evidence of protection based on immunologic data from vaccine and sero-epidemiological studies, complemented by data from opsonophagocytic in vitro assays and animal models, could be considered as pivotal data for licensure, with subsequent confirmation of effectiveness against disease outcomes in post-licensure evaluations. Based on discussions initiated by the World Health Organization we present key considerations about the potential role of correlates of protection towards an accelerated pathway for GBS vaccine licensure and wide scale use. Priority activities to support progress to regulatory and policy decision are outlined. |
Global emergence and population dynamics of divergent serotype 3 CC180 pneumococci.
Azarian T , Mitchell PK , Georgieva M , Thompson CM , Ghouila A , Pollard AJ , von Gottberg A , du Plessis M , Antonio M , Kwambana-Adams BA , Clarke SC , Everett D , Cornick J , Sadowy E , Hryniewicz W , Skoczynska A , Moisi JC , McGee L , Beall B , Metcalf BJ , Breiman RF , Ho PL , Reid R , O'Brien KL , Gladstone RA , Bentley SD , Hanage WP . PLoS Pathog 2018 14 (11) e1007438 Streptococcus pneumoniae serotype 3 remains a significant cause of morbidity and mortality worldwide, despite inclusion in the 13-valent pneumococcal conjugate vaccine (PCV13). Serotype 3 increased in carriage since the implementation of PCV13 in the USA, while invasive disease rates remain unchanged. We investigated the persistence of serotype 3 in carriage and disease, through genomic analyses of a global sample of 301 serotype 3 isolates of the Netherlands3-31 (PMEN31) clone CC180, combined with associated patient data and PCV utilization among countries of isolate collection. We assessed phenotypic variation between dominant clades in capsule charge (zeta potential), capsular polysaccharide shedding, and susceptibility to opsonophagocytic killing, which have previously been associated with carriage duration, invasiveness, and vaccine escape. We identified a recent shift in the CC180 population attributed to a lineage termed Clade II, which was estimated by Bayesian coalescent analysis to have first appeared in 1968 [95% HPD: 1939-1989] and increased in prevalence and effective population size thereafter. Clade II isolates are divergent from the pre-PCV13 serotype 3 population in non-capsular antigenic composition, competence, and antibiotic susceptibility, the last of which resulting from the acquisition of a Tn916-like conjugative transposon. Differences in recombination rates among clades correlated with variations in the ATP-binding subunit of Clp protease, as well as amino acid substitutions in the comCDE operon. Opsonophagocytic killing assays elucidated the low observed efficacy of PCV13 against serotype 3. Variation in PCV13 use among sampled countries was not independently correlated with the CC180 population shift; therefore, genotypic and phenotypic differences in protein antigens and, in particular, antibiotic resistance may have contributed to the increase of Clade II. Our analysis emphasizes the need for routine, representative sampling of isolates from disperse geographic regions, including historically under-sampled areas. We also highlight the value of genomics in resolving antigenic and epidemiological variations within a serotype, which may have implications for future vaccine development. |
Emerging ergonomics issues and opportunities in mining
Dempsey PG , Kocher LM , Nasarwanji MF , Pollard JP , Whitson AE . Int J Environ Res Public Health 2018 15 (11) Ergonomics is the scientific discipline that investigates the interactions between humans and systems to optimize both human and system performance for worker safety, health, and productivity. Ergonomics is frequently involved either in the design of emerging technologies or in strategies to alleviate unanticipated human performance problems with emerging technologies. This manuscript explores several such emerging issues and opportunities in the context of the mining sector. In mining, the equipment, tools, and procedures have changed considerably and continue to change. Body-worn technology provides a number of opportunities to advance the safety and health of miners, while teleoperation and autonomous mining equipment stand to benefit significantly from ergonomics applications in other sectors. This manuscript focuses on those issues and opportunities that can impact the safety and health of miners in the near term. |
Method for measuring wear on boot outsoles using a 3D laser scanner
Whitson AE , Kocher LM , Pollard J , Nasarwanji M . Footwear Sci 2018 10 (3) 149-155 In the mining industry, slips and falls are the second leading cause of non-fatal injuries. Footwear is the primary defence against a slip; consequently, the condition of the footwear outsole is critical to maintaining slip resistance. Currently, there is no published method that can be used to determine when the outsole no longer affords adequate slip protection. Moreover, quantifying the condition of the outsole through the measurement of outsole features can be tedious. This article introduces a new method for the quantification of boot outsole wear. Using a handheld 3D scanner, boot scans can be taken quickly and the developed models used to measure outsole features. This method also accounts for the bending of the boot due to normal wear, which may otherwise introduce erroneous measures. When compared to measurements with a traditional handheld calliper, this new method offers more flexibility in terms of data collection, accounts for other types of boot transformations, and is more efficient to use over multiple measurement periods with no statistically significant differences in measurement. |
The relative invasive disease potential of Streptococcus pneumoniae among children after PCV introduction: a systematic review and meta-analysis
Balsells E , Dagan R , Yildirim I , Gounder PP , Steens A , Munoz-Almagro C , Mameli C , Kandasamy R , Lavi NG , Daprai L , van der Ende A , Trzcinski K , Nzenze S , Meiring S , Foster D , Bulkow LR , Rudolph K , Valero-Rello A , Ducker S , Vestrheim DF , von Gottberg A , Pelton SI , Zuccotti G , Pollard AJ , Sanders EAM , Campbell H , Madhi SA , Nair H , Kyaw MH . J Infect 2018 77 (5) 368-378 OBJECTIVES: Burden of pneumococcal disease depends on the prevalence and invasive disease potential of serotypes. We aimed to estimate the invasive disease potential of serotypes in children under 5 years of age by combining data from different settings with routine immunisation with pneumococcal conjugate vaccines (PCV). METHODS: We conducted a systematic review, supplemented by unpublished data, to identify data on the frequency of pneumococcal serotypes in carriage and invasive pneumococcal disease (IPD). We estimated the invasive disease potential of serotypes as the ratio of IPD in relation to carriage (odds ratio and 95%CI) compared with 19A (reference serotype) by meta-analysis. We report results based on a random effects model for children aged 0-23, 24-29, and 0-59 months and by invasive clinical syndromes. RESULTS: In comparison with 19A, serotypes 1, 7F, and 12F had a significantly higher invasive disease potential in children aged 0-23 and 0-59 months for all IPD and clinical syndromes (OR>5). Several non-vaccine types (NVTs) (6C, 15A, 15BC, 16F, 23B, in these two age groups) had a lower invasive disease potential than 19A (OR 0*1-0*3). NVTs 8, 12F, 24F, and 33F were at the upper end of the invasiveness spectrum. CONCLUSIONS: There is substantial variation among pneumococcal serotypes in their potential to cause IPD and disease presentation, which is influenced by age and time after PCV introduction. Surveillance of IPD and carriage is critical to understand the expected effectiveness of current PCVs (in the longer term) and guide the development of future vaccines. |
An analysis of injuries to front-end loader operators during ingress and egress
Nasarwanji MF , Pollard J , Porter W . Int J Ind Ergon 2017 65 84-92 Slips, trips, and falls from mobile mining equipment have been documented for decades. However, little research has been conducted to determine the events precipitating these incidents during ingress or egress. This study examined slips, trips, and falls sustained during ingress or egress from front-end loaders to determine the frequencies of factors that may contribute to injuries. Non-fatal injuries, when getting on or off of front-end wheel loaders specifically, were identified, coded, and analyzed from the Mine Safety and Health Administration's accidents, injuries, and illnesses database. Overall trends, events that precipitated the injury, injuries sustained, contributing factors, location of the individual, and equipment characteristics were analyzed. More incidents occurred during egress (63%); and egress is believed to be more hazardous than ingress. Foot slips were the most common event that precipitated the incident and the leading cause of these was contaminants on the equipment. Misstep, loss of footing, and step on/in related incidents were more common during egress and are likely due to the operator's reduced visibility when descending a ladder facing the equipment, limiting their ability to detect hazards. Egress also makes an operator less capable of avoiding unsafe ground conditions as indicated by the significant number of step on/in injuries occurring on the ground during egress. Most of the front-end loaders associated with the incidents were found to have bottom rungs with flexible rails, which may also increase fall risk during egress due to inconsistent rung heights and lengthy transition areas from the ground, through the flexible-railed rungs, to the rungs with rigid rails. Recommendations are provided to reduce the risk for slips, trips, and falls from mobile mining equipment. |
Development of ergonomics audits for bagging, haul truck, and maintenance and repair operations in mining
Dempsey PG , Pollard J , Porter WL , Mayton A , Heberger JR , Gallagher S , Reardon L , Drury CG . Ergonomics 2017 60 (12) 1-38 The development and testing of ergonomics and safety audits for small and bulk bag filling, haul truck, and maintenance and repair operations in coal preparation and mineral processing plants found at surface mine sites is described. The content for the audits was derived from diverse sources of information on ergonomics and safety deficiencies including: analysis of injury, illness, and fatality data and reports; task analysis; empirical laboratory studies of particular tasks; field studies and observations at mine sites; and maintenance records. These diverse sources of information were utilized to establish construct validity of the modular audits that were developed for use by mine safety personnel. User and inter-rater reliability testing was carried out prior to finalizing the audits. The audits can be implemented using downloadable paper versions or with a free mobile NIOSH-developed Android application called ErgoMine. Practitioner Summary The methodology used to develop ergonomics audits for three types of mining operations is described. Various sources of audit content are compared and contrasted to serve as a guide for developing ergonomics audits for other occupational contexts. |
Policy making for vaccine use as a driver of vaccine innovation and development in the developed world
Seib K , Pollard AJ , de Wals P , Andrews RM , Zhou F , Hatchett RJ , Pickering LK , Orenstein WA . Vaccine 2017 35 (10) 1380-1389 In the past 200years, vaccines have had unmistakable impacts on public health including declines in morbidity and mortality, most markedly in economically-developed countries. Highly engineered vaccines including vaccines for conditions other than infectious diseases are expected to dominate future vaccine development. We examine immunization vaccine policy as a driver of vaccine innovation and development. The pathways to recommendation for use of licensed vaccines in the US, UK, Canada and Australia have been similar, including: expert review of disease epidemiology, disease burden and severity; vaccine immunogenicity, efficacy and safety; programmatic feasibility; public demand; and increasingly cost-effectiveness. Other attributes particularly important in development of future vaccines are likely to include: duration of immunity for improved vaccines such as pertussis; a greater emphasis on optimizing community protection rather than direct protection only; programmatic implementation, feasibility, improvements (as in the case of development of a universal influenza vaccine); public concerns/confidence/fears related to outbreak pathogens like Ebola and Zika virus; and major societal burden for combating hard to treat diseases like HIV and antimicrobial resistant pathogens. Driving innovation and production of future vaccines faces enormous economic hurdles as available approaches, technologies and regulatory pathways become more complex. As such, cost-mitigating strategies and focused, aligned efforts (by governments, private organizations, and private-public partnerships) will likely be needed to continue to spur major advances in vaccine technologies and development. |
- Page last reviewed:Feb 1, 2024
- Page last updated:May 06, 2024
- Content source:
- Powered by CDC PHGKB Infrastructure