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1.
Open Forum Infect Dis ; 11(3): ofae062, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38524221

ABSTRACT

Background: Despite its global significance, challenges associated with understanding the epidemiology and accurately detecting, measuring, and characterizing the true burden of seasonal influenza remain in many resource-poor settings. Methods: A prospective observational study was conducted in Cambodia at 28 health facilities between 2007 and 2020 utilizing passive surveillance data of patients presenting with acute undifferentiated febrile illness (AUFI) to describe the prevalence of influenza A and B and characterize associated risk factors and symptoms using a questionnaire. A comparison of rapid influenza diagnostic tests (RIDTs) and real-time reverse transcription polymerase chain reaction (rRT-PCR) results was also conducted. Results: Of 30 586 total participants, 5634 (18.4%) tested positive for either influenza A or B, with 3557 (11.6%) positive for influenza A and 2288 (7.5%) positive for influenza B during the study. Influenza A and B were strongly associated with the rainy season (odds ratio [OR], 2.30; P < .001) and being from an urban area (OR, 1.45; P < .001). Analysis of individual symptoms identified cough (OR, 2.8; P < .001), chills (OR, 1.4; P < .001), and sore throat (OR, 1.4; P < .001) as having the strongest positive associations with influenza among patients with AUFI. Analysis comparing RIDTs and rRT-PCR calculated the overall sensitivity of rapid tests to be 0.492 (95% CI, 0.479-0.505) and specificity to be 0.993 (95% CI, 0.992-0.994) for both influenza type A and B. Conclusions: Findings from this 14-year study include describing the epidemiology of seasonal influenza over a prolonged time period and identifying key risk factors and clinical symptoms associated with infection; we also demonstrate the poor sensitivity of RIDTs in Cambodia.

2.
PLoS One ; 18(3): e0283871, 2023.
Article in English | MEDLINE | ID: mdl-37000848

ABSTRACT

Diarrheal diseases are a leading cause of mortality and morbidity, disproportionally affecting persons residing in low and middle-income countries. Accessing high-resolution surveillance data to understand community-level etiology and risk remains challenging, particularly in remote and resource limited populations. A multi-year prospective cohort study was conducted in two rural and two peri-urban villages in Cambodia from 2012 to 2018 to describe the epidemiology and etiology of acute diarrheal diseases within the population. Suspected diarrheal episodes among participants were self-reported or detected via routine weekly household visits. Fresh stool and fecal swabs were tested, and acute-illness and follow-up participant questionnaires collected. Of 5027 enrolled participants, 1450 (28.8%) reported at least one diarrheal incident. A total of 4266 individual diarrhea case events were recorded. Diarrhea incidence rate was calculated to be 281.5 persons per 1000 population per year, with an event rate of 664.3 individual diarrhea events occurring per 1000 population per year. Pathogenic Escherichia coli, Aeromonas spp., and Plesiomonas shigelloides were the most prevalent bacterial infections identified. Hookworm and Strongyloides stercoralis were the predominant helminth species, while Blastocystis hominis and Giardia lamblia were the predominant protozoan species found. Norovirus genotype 2 was the predominant virus identified. Mixed infections of two or more pathogens were detected in 36.2% of positive cases. Risk analyses identified unemployed status increased diarrhea risk by 63% (HR = 1.63 [95% CI 1.46, 1.83]). Individuals without access to protected water sources or sanitation facilities were 59% (HR = 1.59 [95% CI 1.49, 1.69]) and 19% (HR = 1.19 [95% CI 1.12, 1.28]) greater risk of contracting diarrhea, respectively. Patient-level surveillance data captured in this long-term study has generated a unique spatiotemporal profile of diarrheal disease in Cambodia. Understanding etiologies, together with associated epidemiological and community-level risk, provides valuable public health insight to support effective planning and delivery of appropriate local population-targeted interventions.


Subject(s)
Diarrhea , Escherichia coli , Humans , Infant , Urban Population , Cambodia/epidemiology , Prospective Studies , Diarrhea/microbiology , Risk Factors
3.
Burns ; 49(3): 664-669, 2023 05.
Article in English | MEDLINE | ID: mdl-35843807

ABSTRACT

BACKGROUND: An Operation Note should provide a comprehensive account of the details of a surgical procedure performed and document clinically relevant events which occur throughout the procedure. The Royal College of Surgeons of England, in 2014, updated guidelines on specific criteria to be included in operation notes. Standardisation using procedure-specific operation notes has been shown to significantly improve adherence to these guidelines. The aim of this study was to evaluate the quality of operation notes in the Irish National Burns Unit before and after the design and implementation of an electronic patient record and the subsequent introduction of an operation template and a burns surgery specific checklist, within the electronic system. METHODS: A 30-point checklist was designed based on existing sources. Operation notes prior to and following the adoption of a electronic-based operation note were analysed, and then reanalysed following the introduction of a procedure-specific operation note. RESULTS: Ninety-three operation notes were included for analysis. An electronic operation record significantly improved the quality of documentation within our unit. The subsequent procedure specific operation note had a significant improvement across all areas and achieved 100% compliance in many categories. CONCLUSIONS: The use of an electronic patient record to document a patient's procedure has been shown to significantly improve the quality of documentation. One could expect this to result in an improved patient hand-over and subsequent episode of care. We highlight a number of initial pit-falls that others may avoid in their implementation of a digital record.


Subject(s)
Burns , Surgeons , Humans , Burns/surgery , England , Documentation , Checklist
4.
BMC Infect Dis ; 22(1): 949, 2022 Dec 17.
Article in English | MEDLINE | ID: mdl-36526991

ABSTRACT

BACKGROUND: In 2020, the Kingdom of Cambodia experienced a nationwide outbreak of chikungunya virus (CHIKV). Despite an increase in the frequency of outbreaks and expanding geographic range of CHIKV, diagnostic challenges remain, and limited surveillance data of sufficient granularity are available to characterize epidemiological profiles and disease dynamics of the virus. METHODS: An ongoing and long-standing cross-sectional study of acute undifferentiated febrile illness (AUFI) in Cambodia was leveraged to describe the disease epidemiology and characterize the clinical presentation of patients diagnosed with CHIKV during the 2020 outbreak. Participants presenting with AUFI symptoms at ten study locations provided acute and convalescent blood samples and were tested for CHIKV using a reverse transcription-polymerase chain reaction (RT-PCR) and serological diagnostic methods including IgM and IgG. Acute and follow-up clinical data were also collected. RESULTS: From 1194 participant blood samples tested, 331 (27.7%) positive CHIKV cases were detected. Most CHIKV positive individuals (280, 84.6%) reported having a fever 3 to 4 days prior to visiting a health facility. Symptoms including chills, joint pain, nausea, vomiting, and lesions were all statistically significant among CHIKV positive participants compared to CHIKV negative AUFI participants. Cough was negatively associated with CHIKV positive participants. Positivity proportions were significantly higher among adults compared to children. No significant difference was found in positivity proportion between rainy and dry seasons during the outbreak. Positive CHIKV cases were detected in all study site provinces, with the highest test positivity proportion recorded in the rural northeast province of Kratie. CONCLUSIONS: Surveillance data captured in this study provided a clinical and epidemiological characterization of positive CHIKV patients presenting at selected health facilities in Cambodia in 2020, and highlighted the widespread distribution of the outbreak, impacting both urban and rural locations. Findings also illustrated the importance of utilizing both RT-PCR and serological testing for effective CHIKV surveillance.


Subject(s)
Chikungunya Fever , Chikungunya virus , Adult , Child , Humans , Chikungunya Fever/diagnosis , Chikungunya Fever/epidemiology , Cross-Sectional Studies , Cambodia/epidemiology , Antibodies, Viral , Chikungunya virus/genetics , Disease Outbreaks , Fever/epidemiology , Fever/etiology
5.
Med Leg J ; 90(4): 230-233, 2022 Dec.
Article in English | MEDLINE | ID: mdl-35694742

ABSTRACT

This article examines the standard of proof for unlawful killing in coronial proceedings. Historically, the criminal standard of proof governed inquest findings of unlawful killing. In R (Maughan) v Her Majesty's Senior Coroner for Oxfordshire, the Supreme Court resolved the important question of whether the criminal or civil standard governed inquest conclusions of unlawful killing. The court concluded that the correct standard of proof for all conclusions in coronial proceedings is the balance of probabilities. This article argues that whilst preserving differing standards of proof in coronial proceedings was no longer defensible and Maughan has provided welcome clarity, unanswered questions remain concerning the implementation of this fundamental change.


Subject(s)
Coroners and Medical Examiners , Criminals , Female , Humans
6.
PLoS One ; 16(4): e0250045, 2021.
Article in English | MEDLINE | ID: mdl-33861798

ABSTRACT

In-line with the World Health Organization's (WHO) Global Technical Strategy for Malaria (2016-2030), Vietnam is striving to eliminate malaria by 2030. Targeting appropriate interventions in high-risk populations such as forest and forest-fringe communities is a critical component of malaria elimination efforts in Vietnam. In 2016, a household-level malaria indicator survey was conducted in Phu Yen Province, Vietnam with the aim of assessing the knowledge, behaviors and associated risks of malaria infection among priority mobile and migrant populations (MMPs) working and sleeping in forests and on farms. A total of 4211 people were included in the survey, comprised of 1074 heads of households and 3137 associated household members. Of the 1074 head-of-household respondents, 472 slept in a forest, 92 slept on a farm, 132 slept in both forests and farms, and 378 slept at their villages within the last 12 months. Age, literacy, and occupation were significantly different among those who slept in a forest versus on a farm. Of 301 respondents who answered questions about malaria risk factors at sleeping sites, 35% were somewhat aware of malaria prevention practices, but only 4% could recall at least four malaria prevention messages. Among the same group of 301 respondents, only 29% used nets and only 11% used treated nets. Ownership and use of nets among forest-goers was significantly lower than those who slept on a farm or in their village. Huts without walls were significantly prominent forest sleeping site locations (POR = 10.3; 95% CI 4.67-22.7). All respondents who slept in a forest requested standby malaria drugs and one-third of them self-treated without blood testing. Results from this study highlight the importance of capturing relevant location-specific data among priority populations such as remote forest and farm going mobile and migrant populations in Vietnam. Data regarding behavioral practices, knowledge, preventative measures, and intervention coverage at remote-area transmission sites must be routinely captured to effectively monitor progress and refine targeted intervention strategies accordingly.


Subject(s)
Malaria/epidemiology , Malaria/prevention & control , Malaria/transmission , Adult , Cross-Sectional Studies , Environmental Biomarkers , Family Characteristics , Farms , Female , Forests , Humans , Male , Middle Aged , Risk Factors , Surveys and Questionnaires , Transients and Migrants/statistics & numerical data , Vietnam/epidemiology
7.
Am J Trop Med Hyg ; 104(5): 1917-1924, 2021 04 05.
Article in English | MEDLINE | ID: mdl-33819169

ABSTRACT

Strengthening vector control measures among mobile and migrant populations (MMPs) is crucial to malaria elimination, particularly in areas with multidrug-resistant malaria. Although a global priority, providing access and ensuring high coverage of available tools such as long-lasting insecticidal nets (LLINs) among these vulnerable groups remains a significant challenge. We assessed mosquito net ownership, utilization, and preference among individuals who slept in a forest and/or on a farm against those residing only in village "home" settings in a priority malaria elimination area of Vietnam. Proportions of respondents owning bed nets were similar among forest, farm, and home sleeping sites, ranging between 96% and 98%. The proportion of respondents owning hammock nets was higher for the forest group (92%), whereas ownership of hammocks in general was significantly lower for the home group (55%). Most respondents (97%) preferred to bring hammock nets to their remote sleeping site, whereas a smaller proportion (25%) also considered bed nets as an option. Respondent preferences included thick hammock nets with zippers (53%), hammocks with a flip cover (17%), and thin hammock nets with zippers (15%), with none choosing polyethylene (hard) LLINs. Although there is high coverage and access to nets for this high-priority MMP group, there was a noted gap between coverage and net use, potentially undermining the effectiveness of net-related interventions that could impact malaria prevention and elimination efforts in Vietnam. The design and material of nets are important factors for user preferences that appear to drive net use.


Subject(s)
Insecticide-Treated Bednets/supply & distribution , Malaria/prevention & control , Mosquito Control/methods , Ownership/statistics & numerical data , Transients and Migrants/psychology , Cross-Sectional Studies , Farms , Humans , Malaria/epidemiology , Surveys and Questionnaires , Vietnam/epidemiology
8.
J Surg Case Rep ; 2021(1): rjaa583, 2021 Jan.
Article in English | MEDLINE | ID: mdl-33542812

ABSTRACT

A Becker's naevus is a rare, pigmented, cutaneous hamartoma, which when associated with other cutaneous or musculoskeletal anomalies is termed Becker naevus syndrome. Female patients commonly seek medical attention for breast hypoplasia. Here, we describe our experience in the surgical management of unilateral breast hypoplasia in a patient with Becker naevus syndrome, using high-volume autologous fat grafting. This is, to our knowledge, the second report in the literature describing the aforementioned management technique in this patient cohort.

9.
Hip Int ; 31(6): 759-765, 2021 Nov.
Article in English | MEDLINE | ID: mdl-32233664

ABSTRACT

AIMS: To determine the outcome at 10 years of a cohort of ASR XL total hip arthroplasties (THAs) and reasons for revision. METHODS: Between November 2005 and May 2007, 122 ASR XL THAs were implanted. All patients had a routine review at 6 weeks and 1 year, followed by a review in 2009 because of clinical concern and thereafter annual review up to 10 years with MRI. Review also included functional scores, radiographs, pain scores and blood metal ions. RESULTS: 67 (54.9%) ASR XLs had been revised by 11.1 years. Reasons for revision included pain (89.6%), high levels of cobalt and chromium ions (50.7%) and radiographic or MRI changes (80.6%). All 3 factors were present in 23 (34.3%). Pain at 1 year did not predict revision, but pain at the 2009 review did. At 10 years the revised patients had an average Oxford Hip Score (OHS) of 25.38 (12-42) and the non-revised 23.61 (2-21), the difference was not significant (p = 0.48). 3 patients (4.5%) have had a further revision; 2 for a previously unrevised stem and the other for instability. CONCLUSIONS: Our arthroplasty care practitioner service allowed us to identify increased pain and stop using the ASR XL over 3 years before the implant was recalled. The revised patients had similar functional outcome to those unrevised. Poorly performing implants need to be identified earlier.


Subject(s)
Arthroplasty, Replacement, Hip , Hip Prosthesis , Metal-on-Metal Joint Prostheses , Arthroplasty, Replacement, Hip/adverse effects , Chromium , Cobalt , Humans , Prosthesis Design , Prosthesis Failure , Reoperation
10.
BMC Infect Dis ; 20(1): 757, 2020 Oct 15.
Article in English | MEDLINE | ID: mdl-33059623

ABSTRACT

BACKGROUND: Individuals that work and sleep in remote forest and farm locations in the Greater Mekong Subregion continue to remain at high risk of both acquiring and transmitting malaria. These difficult-to-access population groups largely fall outside the reach of traditional village-centered interventions, presenting operational challenges for malaria programs. In Vietnam, over 60% of malaria cases are thought to be individuals who sleep in forests or on farms. New malaria elimination strategies are needed in countries where mobile and migrant workers frequently sleep outside of their homes. The aim of this study was to apply targeted surveillance-response based investigative approaches to gather location-specific data on confirmed malaria cases, with an objective to identify associated malaria prevention, treatment and risk behaviors of individuals sleeping in remote forest and farms sites in Vietnam. METHODS: A cross-sectional study using novel targeted reactive investigative approaches at remote area sleeping sites was conducted in three mountainous communes in Phu Yen province in 2016. Index cases were defined as individuals routinely sleeping in forests or farms who had tested positive for malaria. Index cases and non-infected neighbors from forest and farm huts within 500 m of the established sleeping locations of index cases were interviewed at their remote-area sleeping sites. RESULTS: A total of 307 participants, 110 index cases and 197 neighbors, were enrolled. Among 93 participants who slept in the forest, index cases were more likely to make > 5 trips to the forest per year (prevalence odds ratio (POR) 7.41, 95% confidence interval (CI) 2.66-20.63), sleep in huts without walls (POR 44.00, 95% CI 13.05-148.33), sleep without mosquito nets (POR 2.95, 95% CI 1.26-6.92), and work after dark (POR 5.48, 95% CI 1.84-16.35). Of the 204 farm-based respondents, a significantly higher proportion of index cases were involved in non-farming activities (logging) (POR 2.74, 95% CI 1.27-5.91). CONCLUSION: Investigative approaches employed in this study allowed for the effective recruitment and characterization of high-priority individuals frequently sleeping in remote forest and farm locations, providing relevant population and site-specific data that decision makers can use to design and implement targeted interventions to support malaria elimination.


Subject(s)
Forests , Malaria/epidemiology , Malaria/transmission , Adult , Behavior Therapy , Cross-Sectional Studies , Farms , Female , Housing , Humans , Malaria/drug therapy , Malaria/prevention & control , Male , Middle Aged , Mosquito Nets , Odds Ratio , Risk-Taking , Vietnam/epidemiology , Vietnam/ethnology
11.
Am J Trop Med Hyg ; 103(4): 1540-1548, 2020 10.
Article in English | MEDLINE | ID: mdl-32748781

ABSTRACT

Malaria in Vietnam has become focal to a few provinces, including Phu Yen. This study aimed to assess correlations between intervention (population proportion protected by insecticide-treated nets and indoor residual spraying) and climatic variables with malaria incidence in Phu Yen Province. The Vietnam National Institute of Malariology, Parasitology, and Entomology provided incidence data for Plasmodium falciparum and Plasmodium vivax for 104 communes of Phu Yen Province from January 2005 to December 2016. A multivariable, zero-inflated Poisson regression model was developed with a conditional autoregressive prior structure to identify the underlying spatial structure of the data and quantify associations with covariates. There were a total of 2,778 P. falciparum and 1,770 P. vivax cases during the study period. Plasmodium falciparum and P. vivax incidence increased by 5.4% (95% credible interval [CrI] 5.1%, 5.7%) and 3.2% (95% CrI 2.9%, 3.5%) for a 10-mm increase in precipitation without lag, respectively. Plasmodium falciparum and P. vivax incidence decreased by 7.7% (95% CrI 5.6%, 9.7%) and 10.5% (95% CrI 8.3%, 12.6%) for a 1°C increase in minimum temperature without lag, respectively. There was a > 95% probability of a higher than provincial average trend of P. falciparum and P. vivax in Song Cau and Song Hoa districts. There was a > 95% probability of a lower than provincial average trend in Tuy Dong Xuan and Hoa districts for both species. Targeted distribution of resources, including intensified interventions, in this part of the province will be required for local malaria elimination.


Subject(s)
Malaria, Falciparum/epidemiology , Malaria, Vivax/epidemiology , Plasmodium falciparum/physiology , Plasmodium vivax/physiology , Epidemiological Monitoring , Geography , Humans , Incidence , Malaria, Falciparum/parasitology , Malaria, Vivax/parasitology , Risk , Spatio-Temporal Analysis , Temperature , Vietnam/epidemiology
12.
Malar J ; 18(1): 435, 2019 Dec 20.
Article in English | MEDLINE | ID: mdl-31861988

ABSTRACT

BACKGROUND: The transition from malaria control to elimination requires understanding and targeting interventions among high-risk populations. In Vietnam, forest-goers are often difficult to test, treat and follow-up for malaria because they are highly mobile. If undiagnosed, forest-goers can maintain parasite reservoirs and contribute to ongoing malaria transmission. METHODS: A case-control study was conducted to identify malaria risk factors associated with forest-goers in three communes in Phu Yen Province, Vietnam. Cases (n = 81) were residents from the study area diagnosed with malaria and known to frequent forest areas. Controls (n = 94) were randomly selected forest-going residents from within the study area with no identified malaria infection. Participants were interviewed face-to-face using a standard questionnaire to identify malaria risk factors. Logistic regression was used to calculate odds ratios (ORs) and 95% CI for risk factors after adjusting for socio-demographic characteristics. RESULTS: Among the cases, malaria infection varied by species: 66.7% were positive for Plasmodium falciparum, 29.6% for Plasmodium vivax, and 3.7% were diagnosed as mixed infection. Cases were less likely than controls to use treated nets (aOR = 0.31; 95% CI 0.12-0.80), work after dark (aOR = 2.93; 95% CI 1.35, 6.34), bath in a stream after dark (aOR = 2.44; 95% CI 1.02-5.88), and collect water after dark (aOR = 1.99; 95% CI 1.02-3.90). CONCLUSIONS: As Vietnam moves toward malaria elimination, these findings can inform behaviour change communication and malaria prevention strategies, incorporating the risk of after-dark and water-related activities, in this priority and difficult-to-access population group.


Subject(s)
Malaria, Falciparum/epidemiology , Malaria, Vivax/epidemiology , Plasmodium falciparum/physiology , Plasmodium vivax/physiology , Adult , Case-Control Studies , Female , Forests , Humans , Male , Middle Aged , Prevalence , Risk Factors , Vietnam/epidemiology , Young Adult
13.
Geospat Health ; 14(2)2019 11 06.
Article in English | MEDLINE | ID: mdl-31724368

ABSTRACT

This study examines the development of a spatial decision support system (SDSS) to address operational challenges for combatting malaria in a priority remote forest area of Vietnam including locating active malaria transmission, guiding targeted response, and identifying mobile and high-risk populations. A customized SDSS was developed for three communes in Phu Yen Province, Vietnam. Geographical reconnaissance (GR) was conducted to map and enumerate all households in the study site. During 2015 and 2016, detected malaria cases were reported to the SDSS and georeferenced to household residence. Individual case data were analysed in the SDSS to guide targeted response. Case investigation data, including suspected forest and remote area transmission locations, were also integrated into the SDSS. Surveys and in-depth interviews were conducted to assess utility and user acceptability. In 2015 and 2016, 4,667 households and a population of 17,563 were captured during GR. During the study period, 128 malaria cases were reported and automatically mapped in the SDSS. Targeted response interventions were conducted in 12 villages, testing 1,872 individuals. Intervention and remote-area sleeping site data were mapped and analysed using the SDSS. During follow-up interviews in 2017 the SDSS was found to be highly acceptable to malaria surveillance personnel. Results suggest that an SDSS can provide an effective tool in Vietnam to support the implementation of specialized surveillance, and calls for further research, application and roll-out in the Greater Mekong Subregion.


Subject(s)
Decision Support Techniques , Forests , Malaria/epidemiology , Malaria/prevention & control , Public Health Surveillance/methods , Spatial Analysis , Geographic Information Systems , Geographic Mapping , Humans , Interviews as Topic , Residence Characteristics , Vietnam/epidemiology
15.
Malar J ; 17(1): 480, 2018 Dec 19.
Article in English | MEDLINE | ID: mdl-30567537

ABSTRACT

BACKGROUND: Subpatent malaria infections, or low-density infections below the detection threshold of microscopy or standard rapid diagnostic testing (RDT), can perpetuate persistent transmission and, therefore, may be a barrier for countries like Namibia that are pursuing malaria elimination. This potential burden in Namibia has not been well characterized. METHODS: Using a two-stage cluster sampling, cross-sectional design, subjects of all age were enrolled during the end of the 2015 malaria transmission season in Zambezi region, located in northeast Namibia. Malaria RDTs were performed with subsequent gold standard testing by loop-mediated isothermal amplification (LAMP) using dried blood spots. Infection prevalence was measured and the diagnostic accuracy of RDT calculated. Relationships between recent fever, demographics, epidemiological factors, and infection were assessed. RESULTS: Prevalence of Plasmodium falciparum malaria infection was low: 0.8% (16/1919) by RDT and 2.2% (43/1919) by LAMP. All but one LAMP-positive infection was RDT-negative. Using LAMP as gold standard, the sensitivity and specificity of RDT were 2.3% and 99.2%, respectively. Compared to LAMP-negative infections, a higher portion LAMP-positive infections were associated with fever (45.2% vs. 30.4%, p = 0.04), though 55% of infections were not associated with fever. Agricultural occupations and cattle herding were significantly associated with LAMP-detectable infection (Adjusted ORs 5.02, 95% CI 1.77-14.23, and 11.82, 95% CI 1.06-131.81, respectively), while gender, travel, bed net use, and indoor residual spray coverage were not. CONCLUSIONS: This study presents results from the first large-scale malaria cross-sectional survey from Namibia using molecular testing to characterize subpatent infections. Findings suggest that fever history and standard RDTs are not useful to address this burden. Achievement of malaria elimination may require active case detection using more sensitive point-of-care diagnostics or presumptive treatment and targeted to high-risk groups.


Subject(s)
Malaria, Falciparum/epidemiology , Adolescent , Adult , Aged , Aged, 80 and over , Child , Child, Preschool , Cross-Sectional Studies , Diagnostic Tests, Routine , Female , Humans , Infant , Infant, Newborn , Malaria, Falciparum/diagnosis , Male , Middle Aged , Namibia/epidemiology , Nucleic Acid Amplification Techniques , Prevalence , Risk Factors , Sensitivity and Specificity , Young Adult
16.
Article in English | MEDLINE | ID: mdl-30130673

ABSTRACT

Hydrophobic interaction chromatography (HIC) is routinely used in the purification of biopharmaceuticals such as antibodies. However, hydrophobic proteins can be difficult to elute resulting in low recovery of product thereby complicating early phase process development and potentially excluding the use of HIC resins for their manufacture. Mobile phase additives such as hexylene glycol and arginine facilitate protein elution from resins including HIC; therefore, these additives were evaluated toward the recovery and purification of bispecific and monoclonal antibodies from Phenyl Sepharose HP and Capto Phenyl ImpRes resins. The influences of gradient versus step elution as well as superficial linear velocity on product quality were evaluated. Improved protein recovery and reduction of both soluble product aggregate and host cell protein were observed for the tested antibodies with both hexylene glycol and arginine. Furthermore, the impact of salt removal from the HIC load on protein-resin binding was examined providing opportunities to minimize processing time. This method was successfully scaled using a Phenyl Sepharose HP (5 cm i.d. × 20.0 cm) and Capto Phenyl ImpRes (3.2 cm i.d. × 21.4 cm) column demonstrating potential for manufacturing purposes.


Subject(s)
Antibodies, Monoclonal/isolation & purification , Chromatography, Liquid/methods , Animals , Antibodies, Monoclonal/chemistry , Arginine/chemistry , CHO Cells , Cricetinae , Cricetulus , Hydrophobic and Hydrophilic Interactions , Proteins/chemistry , Sepharose/analogs & derivatives , Sepharose/chemistry
17.
Parasit Vectors ; 11(1): 210, 2018 03 27.
Article in English | MEDLINE | ID: mdl-29587882

ABSTRACT

BACKGROUND: Malaria causes significant morbidity and mortality worldwide. There are several preventive measures that are currently employed, including insecticide-treated nets (ITNs, including long-lasting insecticidal nets and insecticidal-treated bed nets), indoor residual spraying (IRS), prophylactic drugs (PD), and untreated nets (UN). However, it is unclear which measure is the most effective for malaria prevention. We therefore undertook a network meta-analysis to compare the efficacy of different preventive measures on incidence of malaria infection. METHODS: A systematic literature review was undertaken across four medical and life sciences databases (PubMed, Cochrane Central, Embase, and Web of Science) from their inception to July 2016 to compare the effectiveness of different preventive measures on malaria incidence. Data from the included studies were analysed for the effectiveness of several measures against no intervention (NI). This was carried out using an automated generalized pairwise modeling (GPM) framework for network meta-analysis to generate mixed treatment effects against a common comparator of no intervention (NI). RESULTS: There were 30 studies that met the inclusion criteria from 1998-2016. The GPM framework led to a final ranking of effectiveness of measures in the following order from best to worst: PD, ITN, IRS and UN, in comparison with NI. However, only ITN (RR: 0.49, 95% CI: 0.32-0.74) showed precision while other methods [PD (RR: 0.24, 95% CI: 0.004-15.43), IRS (RR: 0.55, 95% CI: 0.20-1.56) and UN (RR: 0.73, 95% CI: 0.28-1.90)] demonstrating considerable uncertainty associated with their point estimates. CONCLUSION: Current evidence is strong for the protective effect of ITN interventions in malaria prevention. Even though ITNs were found to be the only preventive measure with statistical support for their effectiveness, the role of other malaria control measures may be important adjuncts in the global drive to eliminate malaria.


Subject(s)
Communicable Disease Control/methods , Disease Transmission, Infectious/prevention & control , Malaria/epidemiology , Malaria/prevention & control , Biostatistics , Humans , Incidence , Network Meta-Analysis , Treatment Outcome
18.
Biotechnol Prog ; 34(1): 120-129, 2018 01.
Article in English | MEDLINE | ID: mdl-28726323

ABSTRACT

During purification process development of a recombinant therapeutic protein, an endoproteolytic activity endogenous to the Chinese hamster ovary (CHO) cells and leading to degradation at particular hydrophobic amino acid residues (e.g., Phe and Trp) was observed when processing at acidic pH. The presence of residual levels of protease activity in purified protein batches affected the inherent activity of the product when stored as a solution. To develop a robust purification strategy to minimize this undesirable impact, identification and characterization of this protease was essential to ultimately ensure that a solution formulation was stable for many years. A protease was isolated from CHO cell-free medium (CFM) using a combination of immobilized pepstatin-A agarose chromatography and size exclusion chromatography (SEC). The isolated protease has significant proteolytic activity at pH ∼ 3 to neutral pH and was identified as cathepsin D by mass spectrometry. Analytical SEC, chip-based capillary gel electrophoresis, imaged capillary isoelectric focusing (cIEF), and circular dichroism (CD) spectropolarimetry analyses were performed for additional characterization of the protease. The identification and characterization of this protease enabled the development of a robust purification process by implementation of a controlled temperature inactivation unit operation (heat inactivation) that enabled essentially complete inactivation of the protease, resulting in the production of a stable drug product that had not been possible using column chromatography alone. © 2017 American Institute of Chemical Engineers Biotechnol. Prog., 34:120-129, 2018.


Subject(s)
Cathepsin D/chemistry , Endopeptidases/chemistry , Proteolysis , Recombinant Proteins/chemistry , Amino Acids/chemistry , Amino Acids/genetics , Animals , CHO Cells , Cathepsin D/isolation & purification , Chromatography, Affinity , Circular Dichroism , Cricetulus , Endopeptidases/isolation & purification , Hydrogen-Ion Concentration , Isoelectric Focusing , Mass Spectrometry , Protein Stability , Recombinant Proteins/isolation & purification
19.
Lancet Infect Dis ; 16(10): e214-e224, 2016 10.
Article in English | MEDLINE | ID: mdl-27527748

ABSTRACT

The malaria situation in India is complex as a result of diverse socio-environmental conditions. India contributes a substantial burden of malaria outside sub-Saharan Africa, with the third highest Plasmodium vivax prevalence in the world. Successful malaria control in India is likely to enhance malaria elimination efforts in the region. Despite modest gains, there are many challenges for malaria elimination in India, including: varied patterns of malaria transmission in different parts of the country demanding area-specific control measures; intense malaria transmission fuelled by favourable climatic and environment factors; varying degrees of insecticide resistance of vectors; antimalarial drug resistance; a weak surveillance system; and poor national coordination of state programmes. Prevention and protection against malaria are low as a result of a weak health-care system, as well as financial and socioeconomic constraints. Additionally, the open borders of India provide a potential route of entry for artesunate-resistant parasites from southeast Asia. This situation calls for urgent dialogue around tackling malaria across borders-between India's states and neighbouring countries-through sharing of information and coordinated control and preventive measures, if we are to achieve the aim of malaria elimination in the region.


Subject(s)
Climate , Disease Transmission, Infectious/prevention & control , Drug Resistance, Multiple , Malaria/prevention & control , Animals , Antimalarials/pharmacology , Delivery of Health Care , Humans , India/epidemiology , International Cooperation , Malaria/drug therapy , Malaria/epidemiology , Malaria/parasitology , Plasmodium vivax/parasitology
20.
Lancet Glob Health ; 4(5): e336-43, 2016 May.
Article in English | MEDLINE | ID: mdl-27102197

ABSTRACT

INTRODUCTION: The number of malaria cases has fallen in Bhutan in the past two decades, and the country has a goal of complete elimination of malaria by 2016. The aims of this study are to ascertain the trends and burden of malaria, the costs of intensified control activities, the main donors of funding for the control activities, and the costs of different preventive measures in the pre-elimination phase (2006-14) in Bhutan. METHODS: We undertook a descriptive analysis of malaria surveillance data from 2006 to 2014, using data from the Vector-borne Disease Control Programme (VDCP) run by the Department of Public Health of Bhutan's Ministry of Health. Malaria morbidity and mortality in local Bhutanese people and foreign nationals were analysed. The cost of different control and preventive measures were calculated, and the average numbers of long-lasting insecticidal nests per person were estimated. FINDINGS: A total of 5491 confirmed malaria cases occurred in Bhutan between 2006 and 2014. By 2013, there was an average of one long-lasting insecticidal net for every 1·51 individuals. The cost of procuring long-lasting insecticidal nets accounted for more than 90% of the total cost of prevention measures. The Global Fund to Fight AIDS, Tuberculosis and Malaria was the main international donor, accounting for more than 80% of the total funds. INTERPRETATION: The malaria burden in Bhutan decreased significantly during the study period with high coverage of long-lasting insecticidal nets. The foreseeable challenges that require national attention to maintain a malaria-free status after elimination are importation of malaria, especially from India; continued protection of the population in endemic districts through complete coverage with long-lasting insecticidal nets and indoor residual spraying; and exploration of local funding modalities post-elimination in the event of a reduction in international funding. FUNDING: None.


Subject(s)
Disease Eradication/economics , Healthcare Financing , Malaria/epidemiology , Mosquito Control/economics , Bhutan/epidemiology , Costs and Cost Analysis , Humans , Insecticide-Treated Bednets , Insecticides/therapeutic use , Malaria/economics , Malaria/prevention & control
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