Interventions to prevent post-tuberculosis sequelae: a systematic review and meta-analysis

Background

Tuberculosis (TB) remains a global public health challenge, causing substantial mortality and morbidity. While TB treatment has made significant progress, it often leaves survivors with post-TB sequelae, resulting in long-term health issues. Current healthcare systems and guidelines lack comprehensive strategies to address post-TB sequelae, primarily due to insufficient evidence. This systematic review and meta-analysis aimed to identify effective interventions for preventing post-TB sequelae.

Methods

A systematic search was conducted across four databases including PubMed, SCOPUS, Web of Science, and Cochrane Central Register of Controlled Trials from inception to September 22, 2023. Eligible studies reported interventions designed to prevent post-TB sequelae were included. A random effect meta-analysis was conducted where applicable, and heterogeneity between studies was evaluated visually using forest plots and quantitatively using an index of heterogeneity (I2). This study is registered with PROSPERO (CRD42023464392).

Findings

From the 2525 unique records screened, 25 studies involving 10,592 participants were included. Different interventions were evaluated for different outcomes. However, only a few interventions were effective in preventing post-TB sequelae. Rehabilitation programs significantly improved lung function (Hedges's g = 0.21; 95% confidence interval (CI): 0.03, 0.39) and prevented neurological sequelae (relative risk (RR) = 0.10; 95% CI: 0.02, 0.42). Comprehensive interventions and cognitive-behavioural therapy significantly reduced the risk of mental health disorders among TB survivors (Hedges's g = -1.89; 95% CI: -3.77, -0.01). In contrast, interventions targeting post-TB liver sequelae, such as vitamin A and vitamin D supplementation and hepatoprotective agents, did not show significant reductions in sequelae (RR = 0.90; 95% CI: 0.52, 1.57). Moreover, adjunctive therapies did not show a significant effect in preventing post-TB neurological sequelae (RR = 0.62, 95% CI: 0.31, 1.24).

Interpretation

Rehabilitation programs prevented post-TB lung, neurologic and mental health sequelae, while adjuvant therapies and other interventions require further investigation.

Funding

Healy Medical Research Raine Foundation, Curtin School of Population Health and the Australian National Health and Medical Research Council.

Impacts of armed conflicts on tuberculosis burden and treatment outcomes: a systematic review

OBJECTIVES

This systematic review aimed to summarise existing literature on the impacts of armed conflicts on tuberculosis burden and treatment outcomes.

DESIGN

A systematic review following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines.

DATA SOURCES

PubMed, Web of Science, Cumulative Index to Nursing and Allied Health Literature Plus, Scopus, ScienceDirect, Embase and medRxiv.

DATA EXTRACTION AND SYNTHESIS

Three reviewers independently screened, selected eligible studies and extracted data. A narrative review was undertaken to summarise the findings qualitatively.

RESULTS

Eleven studies were included in this review, reporting on tuberculosis incidence rates, prevalence and treatment outcomes, including mortality. Overall, the impact of armed conflicts on case notifications was variable. Six studies reported overall increases in tuberculosis case notifications following the onset of conflicts, while three studies reported overall decreases in tuberculosis case notifications. Factors, including limited access to healthcare services, challenges in surveillance and laboratory confirmation, the destruction of health systems and incapacitating the healthcare workforce, contributed to a decrease in the number of notified cases. The higher tuberculosis notification in some of the studies could be attributed to the disruption of tuberculosis prevention and control programmes as well as increased socioeconomic deprivation, including malnutrition, mass migration, poor living conditions and overcrowding that are worsened during conflicts. Armed conflicts without effective interventions were associated with worse tuberculosis treatment outcomes, including lower proportions of people with treatment success and higher proportions of people with loss to follow-up, mortality and treatment failure. However, implementing various interventions in conflict settings (such as establishing a National Tuberculosis Control Programme) led to higher tuberculosis notification rates and treatment success.

CONCLUSION

The impact of armed conflicts on tuberculosis notification is complex and is influenced by multiple factors. The findings of this review underscore the importance of concerted efforts to control tuberculosis in conflict settings using available resources.

Community engagement approaches for malaria prevention, control and elimination: a scoping review

INTRODUCTION

Globally malaria programmes have adopted approaches to community engagement (ACE) to design and deliver malaria interventions. This scoping review aimed to understand, map, and synthesise intervention activities guided by ACE and implemented by countries worldwide for the prevention, control and elimination of malaria.

METHODS

Three databases (Web of Science, Proquest, and Medline) were searched for peer-reviewed, primary studies, published in English between 1 January 2000 and 31 December 2022. Advanced Google was used to search for grey literature. The five levels of the International Association for Public Participation were used to categorise ACE - (1) Inform, (2) Consult, (3) involve, (4) Collaborate, and (5) Co-lead. Intervention activities were categorised as health education (HE), and/or health services (HS), and/or environmental management (EM). Outcomes were collected as knowledge, attitude, behaviour, help-seeking, health and HS and environment. Enablers and barriers were identified. Malaria intervention phases were categorised as (1) prevention (P), or (2) control (C), or (3) prevention and control (PC) or prevention, control and elimination (PCE).

RESULTS

Seventy-five studies were included in the review. Based on ACE levels, most studies were at the inform (n=37) and involve (n=26) level. HE (n=66) and HS (n=43) were the common intervention activities. HE informed communities about malaria, its prevention and vector control. EM activities were effective when complemented by HE. Community-based HS using locally recruited health workers was well-accepted by the community. Involvement of local leaders and collaboration with local stakeholders can be enablers for malaria intervention activities.

CONCLUSION

Involving local leaders and community groups in all stages of malaria prevention programmes is vital for successful interventions. Key elements of successful ACE, that is, consult, collaborate, and co-lead were under-represented in the literature and require attention. National programes must consult and collaborate with community stakeholders to develop ownership of the interventions and eventually co-lead them.

Determinants of drug-resistant tuberculosis in Hunan province, China: a case-control study

BACKGROUND

Drug-resistant tuberculosis (DR-TB) is a major public health threat in Hunan Province, with an increasing clinical burden in recent years. This study aimed to identify socio-demographic and clinical factors associated with DR-TB in Hunan province, China.

METHODS

A case-control study was conducted in Hunan province. Cases were all DR-TB patients who were confirmed by culture and Drug susceptibility testing (DST) and enrolled at the DR-TB treatment center of Hunan Chest Hospital from 2013 to 2018. Controls were all Drug Susceptible TB (DS-TB) patients confirmed by DST and enrolled at the same hospital during the same period. A multivariable logistic regression model was fitted to identify factors significantly associated with DR-TB.

RESULTS

A total of 17,808 patients (15,534 DS-TB controls and 2274 DR-TB cases) were included in the study, with a mean age of 42.5 years (standard deviation (SD) ± 17.5 years) for cases and 46.1 years (SD ± 19.1 years) for controls. Age 15-64 years (Adjusted odds ratio (AOR = 1.5, 95% CI; 1.4, 1.8)), ethnic minorities (AOR = 1.5; 95% CI; 1.4, 1.8), and a history of previous TB treatment (AOR) = 1.84; 95% CI: 1.57, 2.15) was significantly associated with DR-TB. Being resident in a province outside Hunan was also a significant risk factor (AOR = 1.67; 1.27, 2.21) for DR-TB.

CONCLUSION AND RECOMMENDATIONS

To prevent the occurrence of DR-TB in Hunan Province, interventions should be targeted at high-risk demographic groups such as ethnic minorities, individuals of productive age, and residents living outside the province. Interventions must also be targeted to previously treated cases, suggesting the appropriateness of diagnosis, treatment, and follow-up. Understanding the risk factors at the province level helps design strategies for controlling DR-TB due to variations by socioeconomic differences, quality of health care, and healthcare access.

Serological Comparison of Native Antigen ELISAs with Rapid ICT Test Kits for the Diagnosis of Human Alveolar and Cystic Echinococcosis in China

BACKGROUND

The aim of this study was to compare the diagnostic performance of native antigen ELISAs and ADAMU-AE/CE commercial ICT test kits in subjects either exposed to Echinococcus infection or with clinically diagnosed alveolar (AE) or cystic (CE) echinococcosis.

METHODS

A total of 370 subjects with a previous clinical confirmation of CE or AE from northwestern China were recruited. Serum samples were also obtained from 3923 children/teenagers during a community survey. All sera were tested using native antigen ELISAs. The ADAMU-AE/CE test kits were subsequently used for the serology of the 370 clinically confirmed individuals and of 251 children/teenagers that were ELISA antibody-positive for both Echinococcus species but ultrasound-negative during baseline survey. An analysis of the association between the serological tests and ultrasound classification was carried out amongst 89 AE and 164 CE cases. A Kappa consistency analysis was undertaken to compare the diagnostic performance of the native antigen ELISAs and the ADAMU kits and the ultrasound imaging results. The χ² test was also used for a comparison of the different seropositivity rates between the groups.

FINDINGS

There was poor consistency (Kappa = 0.26 and 0.28 for AE and CE respectively) between the native antigen ELISAs and the ADAMU kits for the diagnosis of AE and CE among the cases and the surveyed children/teenagers, but a relatively good consistency (Kappa = 0.63) between the ADAMU-AE kit and ultrasound observations for the AE cases. Additionally, of the 251 teenagers co-positive for both AE and CE antibodies by the native antigen ELISAs, only one was found positive by the ADAMU-AE kit, verified as a new AE case on subsequent ultrasound follow-up. The remainder (N = 250) were negative by serology using the ADAMU-AE/CE kits and by ultrasound examination. The two native antigen ELISAs did not discriminate well between cases of clinically diagnosed AE and CE. In contrast, ADAMU-AE and ADAMU-CE commercial ICT test kits readily differentiated cases of AE from CE with specificities of 99% for AE and 100% for CE.

CONCLUSIONS

The ADAMU-AE/CE kits proved reliable, accurate, and amenable diagnostic tools in the clinical setting for confirmation of suspected AE/CE cases. The native antigen ELISAs tests can provide useful information on the level of human exposure to Echinococcus infection.

Risk factors for diagnosis and treatment delay among patients with multidrug-resistant tuberculosis in Hunan Province, China

BACKGROUND

Multidrug-resistant tuberculosis (MDR-TB) is a global health threat associated with high morbidity and mortality rates. Diagnosis and treatment delays are associated with poor treatment outcomes in patients with MDR-TB. However, the risk factors associated with these delays are not robustly investigated, particularly in high TB burden countries such as China. Therefore, this study aimed to measure the length of diagnosis and treatment delays and identify their risk factors among patients with MDR-TB in Hunan province.

METHODS

A retrospective cohort study was conducted using MDR-TB data from Hunan province between 2013 and 2018. The main outcomes of the study were diagnosis and treatment delay, defined as more than 14 days from the date of symptom to diagnosis confirmation (i.e., diagnosis delay) and from diagnosis to treatment commencement (i.e., treatment delay). A multivariable logistic regression model was fitted, and an adjusted odds ratio (AOR) with a 95% confidence interval (CI) was used to identify factors associated with diagnosis and treatment delay.

RESULTS

In total, 1,248 MDR-TB patients were included in this study. The median length of diagnosis delays was 27 days, and treatment delays were one day. The proportion of MDR-TB patients who experienced diagnosis and treatment delay was 62.82% (95% CI: 60.09-65.46) and 30.77% (95% CI: 28.27-33.39), respectively. The odds of experiencing MDR-TB diagnosis delay among patients coming through referral and tracing was reduced by 41% (AOR = 0.59, 95% CI: 0.45-0.76) relative to patients identified through consultations due to symptoms. The odds of experiencing diagnosis delay among ≥ 65 years were 65% (AOR = 0.35, 0.14-0.91) lower than under-15 children. The odds of developing treatment delay among foreign nationalities and people from other provinces were double (AOR = 2.00, 95% CI: 1.31-3.06) compared to the local populations. Similarly, the odds of experiencing treatment delay among severely ill patients were nearly 2.5 times higher (AOR = 2.49, 95% CI: 1.41-4.42) compared to patients who were not severely ill. On the other hand, previously treated TB cases had nearly 40% (AOR = 0.59, 95% CI: 0.42-0.85) lower odds of developing treatment delay compared with new MDR-TB cases. Similarly, other ethnic minority groups had nearly 40% (AOR = 0.57, 95% CI: 0.34-0.96) lower odds of experiencing treatment delay than the Han majority.

CONCLUSIONS

Many MDR-TB patients experience long diagnosis and treatment delays in Hunan province. Strengthening active case detection can significantly reduce diagnosis delays among MDR-TB patients. Moreover, giving attention to patients who are new to MDR-TB treatment, are severely ill, or are from areas outside Hunan province will potentially reduce the burden of treatment delay among MDR-TB patients.

Burden of drug-resistant tuberculosis among contacts of index cases: a protocol for a systematic review

INTRODUCTION

People having close contact with drug-resistant tuberculosis (DR-TB) patients are at increased risk of contracting and developing the disease. However, no comprehensive review has been undertaken to estimate the burden of DR-TB among contacts of DR-TB patients. Therefore, the current systematic review will quantify the prevalence and incidence of DR-TB among contacts of DR-TB patients.

METHOD AND ANALYSIS

Systematic searches will be conducted in Medline, Embase, Web of Science, Scopus, Cochrane Central Register of Controlled trials (CENTRAL) and Cumulative Index to Nursing and Allied Health Literature (CINHAL) databases. The search will be conducted without restrictions on time, language and geography. A random-effects meta-analysis will be conducted for effect estimates. The pooled prevalence and incidence of DR-TB will be compared between people with and without contact with DR-TB patients. The presence of heterogeneity between studies will be assessed by Higgins I2 statistics. Subgroup analysis will be conducted to determine the source of heterogeneity. The risk of bias will be assessed using a visual inspection of the funnel plot and Egger's regression test statistics. Trim and fill analysis will be done in the presence of publication bias. A sensitivity analysis will be conducted by trimming low-quality studies. The systematic review will be reported according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses Protocol guidelines.

ETHICS AND DISSEMINATION

Ethical approval will not be required for this study as it will be a systematic review and meta-analysis based on previously published evidence. The findings of the systematic review will be presented at scientific conferences and published in scientific journals.

PROTOCOL REGISTRATION

The protocol is published in PROSPERO with registration number CRD42023390339.

Economic burden of multidrug-resistant tuberculosis on patients and households: a global systematic review and meta-analysis

Multidrug-resistant tuberculosis (MDR-TB) is a major health threat worldwide, causing a significant economic burden to patients and their families. Due to the longer duration of treatment and expensive second-line medicine, the economic burden of MDR-TB is assumed to be higher than drug-susceptible TB. However, the costs associated with MDR-TB are yet to be comprehensively quantified. We conducted this systematic review and meta-analysis to determine the global burden of catastrophic costs associated with MDR-TB on patients and their households. We systematically searched five databases (CINHAL, MEDLINE, Embase, Scopus, and Web of Science) from inception to 2 September 2022 for studies reporting catastrophic costs on patients and affected families of MDR-TB. The primary outcome of our study was the proportion of patients and households with catastrophic costs. Costs were considered catastrophic when a patient spends 20% or more of their annual household income on their MDR-TB diagnosis and care. The pooled proportion of catastrophic cost was determined using a random-effects meta-analysis. Publication bias was assessed using visualization of the funnel plots and the Egger regression test. Heterogeneity was assessed using I2, and sub-group analysis was conducted using study covariates as stratification variables. Finally, we used the Preferred Reporting Items for Reporting Systematic Review and Meta-Analysis-20 (PRISMA-20). The research protocol was registered in PROSPERO (CRD42021250909). Our search identified 6635 studies, of which 11 were included after the screening. MDR-TB patients incurred total costs ranging from $USD 650 to $USD 8266 during treatment. The mean direct cost and indirect cost incurred by MDR-TB patients were $USD 1936.25 (SD ± $USD 1897.03) and $USD 1200.35 (SD ± $USD 489.76), respectively. The overall burden of catastrophic cost among MDR-TB patients and households was 81.58% (95% Confidence Interval (CI) 74.13-89.04%). The catastrophic costs incurred by MDR-TB patients were significantly higher than previously reported for DS-TB patients. MDR-TB patients incurred more expenditure for direct costs than indirect costs. Social protection and financial support for patients and affected families are needed to mitigate the catastrophic economic consequences of MDR-TB.

Development and validation of a risk prediction model for pulmonary tuberculosis among presumptive tuberculosis cases in Ethiopia

BACKGROUND

Early diagnosis and treatment of tuberculosis (TB) is one of the key strategies to achieve the WHO End TB targets. This study aimed to develop and validate a simple, convenient risk score to diagnose pulmonary TB among presumptive TB cases.

METHODS

This prediction model used Ethiopian national TB prevalence survey data and included 5459 presumptive TB cases from all regions of Ethiopia. Logistic regression was used to determine which variables are predictive of pulmonary TB. A risk prediction model was developed, incorporating significant variables (p<0.05). The Youden Index method was used to choose the optimal cut-off point to separate the risk score of the patients as high and low. Model performance was assessed using discrimination power and calibration. Internal validation of the model was assessed using Efron's enhanced bootstrap method, and the clinical utility of the risk score was assessed using decision curve analysis.

RESULTS

Of total participants, 94 (1.7%) were confirmed to have TB. The final prediction model included three factors with different scores: (1) TB contact history, (2) chest X-ray (CXR) abnormality and (3) two or more symptoms of TB. The optimal cut-off point for the risk score was 6 and was found to have a good discrimination accuracy (c-statistic=0.70, 95% CI: 0.65 to 0.75). The risk score has sensitivity of 51.1%, specificity of 79.9%, positive predictive value of 4.3% and negative predictive value of 98.9%. After internal validation, the optimism coefficient was 0.003, which indicates the model is internally valid.

CONCLUSION

We developed a risk score that combines TB contact, number of TB symptoms and CXR abnormality to estimate individual risk of pulmonary TB among presumptive TB cases. Though the score is easy to calculate and internally validated, it needs external validation before widespread implementation in a new setting.

Relative Risks of Adverse Perinatal Outcomes in Three Australian Communities Exposed to Per- and Polyfluoroalkyl Substances: Data Linkage Study

INTRODUCTION

Firefighting foams containing per- and polyfluoroalkyl substances (PFAS) have caused environmental contamination in several Australian residential areas, including Katherine in the Northern Territory (NT), Oakey in Queensland (Qld), and Williamtown in New South Wales (NSW). We examined whether the risks of adverse perinatal outcomes were higher in mothers living in these exposure areas than in selected comparison areas without known contamination.

METHODS

We linked residential addresses in exposure areas to addresses collected in the jurisdictional Perinatal Data Collections of the NT (1986-2017), Qld (2007-2018), and NSW (1994-2018) to select all pregnancies from mothers who gave birth while living in these areas. We also identified one comparison group for each exposure area by selecting pregnancies where the maternal address was in selected comparison areas. We examined 12 binary perinatal outcomes and three growth measurements. For each exposure area, we estimated relative risks (RRs) of adverse outcomes and differences in means of growth measures, adjusting for sociodemographic characteristics and other potential confounders.

RESULTS

We included 16,970 pregnancies from the NT, 4654 from Qld, and 7475 from NSW. We observed elevated risks of stillbirth in Oakey (RR = 2.59, 95% confidence interval (CI) 1.25 to 5.39) and of postpartum haemorrhage (RR = 1.94, 95% CI 1.13 to 3.33) and pregnancy-induced hypertension (RR = 1.88, 95% CI 1.30 to 2.73) in Williamtown. The risks of other perinatal outcomes were not materially different from those in the relevant comparison areas or were uncertain due to small numbers of events.

CONCLUSIONS

There was limited evidence for increased risks of adverse perinatal outcomes in mothers living in areas with PFAS contamination from firefighting foams. We found higher risks of some outcomes in individual areas, but these were not consistent across all areas under study and could have been due to chance, bias, or confounding.

Effectiveness of nutritional support to improve treatment adherence in patients with tuberculosis: a systematic review

CONTEXT

Nutritional interventions substantially improve tuberculosis (TB) treatment outcomes and prevent complications. However, there is limited evidence about the connections between having nutritional support and TB treatment adherence.

OBJECTIVE

The aim of this study was to determine the effectiveness of nutritional support in improving treatment adherence among patients with TB.

DATA SOURCES

Databases, including PubMed, Embase (Ovid), Web of Science, and Scopus, were comprehensively reviewed to identify relevant studies reporting the impacts of nutritional support on TB treatment adherence.

DATA EXTRACTION

Two authors independently screened the title, abstracts, and full article texts to identify eligible studies and assess the risk of bias. Observational and interventional studies were included.

DATA ANALYSIS

A narrative synthesis approach was used to summarize the findings qualitatively.

RESULTS

From the search, 3059 publications were identified; of these, 8 studies were included in this systematic review. Three types of nutritional interventions were identified: food baskets (eg, energy, micronutrient- or macronutrient-enriched food support), nutritional advice and guidance, and incentives for buying foods. Although 5 studies reported that nutritional support significantly improved treatment adherence in patients with TB, 3 studies showed that nutritional support had no effect on TB treatment adherence.

CONCLUSIONS

Providing nutritional support may improve adherence to TB treatment. However, more well-powered, high-quality trials are warranted to demonstrate the effect of nutrition support on cost-effectively improving adherence to TB treatment.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO registration no. CRD42023392162.

Spatial predictive risk mapping of lymphatic filariasis residual hotspots in American Samoa using demographic and environmental factors

BACKGROUND

American Samoa successfully completed seven rounds of mass drug administration (MDA) for lymphatic filariasis (LF) from 2000-2006. The territory passed the school-based transmission assessment surveys in 2011 and 2015 but failed in 2016. One of the key challenges after the implementation of MDA is the identification of any residual hotspots of transmission.

METHOD

Based on data collected in a 2016 community survey in persons aged ≥8 years, Bayesian geostatistical models were developed for LF antigen (Ag), and Wb123, Bm14, Bm33 antibodies (Abs) to predict spatial variation in infection markers using demographic and environmental factors (including land cover, elevation, rainfall, distance to the coastline and distance to streams).

RESULTS

In the Ag model, females had a 26.8% (95% CrI: 11.0-39.8%) lower risk of being Ag-positive than males. There was a 2.4% (95% CrI: 1.8-3.0%) increase in the odds of Ag positivity for every year of age. Also, the odds of Ag-positivity increased by 0.4% (95% CrI: 0.1-0.7%) for each 1% increase in tree cover. The models for Wb123, Bm14 and Bm33 Abs showed similar significant associations as the Ag model for sex, age and tree coverage. After accounting for the effect of covariates, the radii of the clusters were larger for Bm14 and Bm33 Abs compared to Ag and Wb123 Ab. The predictive maps showed that Ab-positivity was more widespread across the territory, while Ag-positivity was more confined to villages in the north-west of the main island.

CONCLUSION

The findings may facilitate more specific targeting of post-MDA surveillance activities by prioritising those areas at higher risk of ongoing transmission.

Epidemiology of soil-transmitted helminths using quantitative PCR and risk factors for hookworm and Necator americanus infection in school children in Dak Lak province, Vietnam

BACKGROUND

Soil-transmitted helminth (STH) infection is driven by a complex interaction of demographic, socioeconomic and behavioural factors, including those related to water, sanitation and hygiene (WASH). Epidemiological studies that measure both infection and potential risk factors associated with infection help to understand the drivers of transmission in a population and therefore can provide information to optimise STH control programmes.

METHODS

During October and November 2019, we conducted a cross-sectional survey of the prevalence and intensity of STH infection and associated risk factors among 7710 primary-school-age children from 64 primary schools across 13 districts in Dak Lak province, Vietnam. Quantitative PCR (qPCR) was used to detect and quantify STH infections.

RESULTS

The predominant STH species was the hookworm Necator americanus (overall cluster-adjusted prevalence of 13.7%), and its prevalence was heterogeneously distributed across surveyed schools (0% to 56.3%). All other STH species had a prevalence of less than 1%. Using mixed-effects logistic regression, we found that the adjusted odds ratio (aOR) was significantly higher for both infection and moderate-to-heavy-intensity infection with N. americanus among children from multiple ethnic minority groups, compared to children from the majority group (Kinh). Adjusted odds of infection with N. americanus were also higher in children who reported practising open defecation at school (aOR 1.42, 95% CI 1.05, 1.93, P = 0.02) and in those who had an unimproved household water supply (aOR 1.28, 95% CI 1.04, 1.57, P = 0.02). Conversely, children with a flushing household toilet had a reduced risk of infection (aOR 0.58, 95% CI 0.47, 0.70, P < 0.01), as did those whose primary female carer attended secondary (aOR 0.65, 95% CI 0.51, 0.84, P < 0.01) or tertiary education (aOR 0.39, 95% CI 0.24, 0.63, P < 0.01).

CONCLUSIONS

This study is the largest reported prevalence survey of STH infections conducted using qPCR as a diagnostic technique. The findings of higher adjusted odds of infection amongst ethnic minority children highlight that STH control programmes may not be reaching certain population groups and that additional culturally appropriate approaches may be required. Additionally, the associations between specific WASH factors and infection indicate potential programmatic targets to complement preventive chemotherapy programmes.

Spatial and Temporal Data Visualisation for Mass Dissemination: Advances in the Era of COVID-19

The COVID-19 pandemic is the first major pandemic of the digital age and has been characterised by unprecedented public consumption of spatial and temporal disease data, which can enable greater transparency and accountability of governments to the public for their public health decisions. A variety of state and non-state actors have collated and presented maps, charts, and plots of data related to the pandemic in both static and dynamic formats. In particular, there has been a proliferation of online dashboards presenting data related to the pandemic. The sources and types of information displayed have evolved rapidly during the pandemic, with a general trend towards providing more specialised information pertinent to specific aspects of epidemiology or disease control, as opposed simply to disease and death notifications. Limited evaluation of the quality of COVID-19 data visualisation tools has been conducted and significant effort now needs to be spent on standardisation and quality improvement of national and international data visualisation systems including developing common indicators, data quality assurance mechanisms and visualisation approaches, and building compatible electronic systems for data collection and sharing. The increasing availability of disease data for public consumption presents challenges and opportunities for government, media organisations, academic research institutions, and the general public. A key challenge is ensuring consistency and effectiveness of public health messaging to ensure a coordinated response and public trust in intervention strategies. Capitalising on opportunities for greater government accountability for public health decision-making, and more effective mobilisation of public health interventions, is predicated on the provision of accurate and timely information.

Psychological distress in three Australian communities living with environmental per- and polyfluoroalkyl substances contamination

BACKGROUND

Environmental chemical contamination is a recognised risk factor for psychological distress, but has been seldom studied in the context of per- and polyfluoroalkyl substances (PFAS) contamination. We examined psychological distress in a cross-sectional study of three Australian communities exposed to PFAS from the historical use of aqueous film-forming foam in firefighting activities, and three comparison communities without environmental contamination.

METHODS

Participation was voluntary following recruitment from a PFAS blood-testing program (exposed) or random selection (comparison). Participants provided blood samples and completed a survey on their exposure history, sociodemographic characteristics, and four measures of psychological distress (Kessler-6, Distress Questionnaire-5, Patient Health Questionnaire-15, and Generalised Anxiety Disorder-7). We estimated prevalence ratios (PR) of clinically-significant psychological distress scores, and differences in mean scores: (1) between exposed and comparison communities; (2) per doubling in PFAS serum concentrations in exposed communities; (3) for factors that affect the perceived risk of living in a community exposed to PFAS; and (4) in relation to self-reported health concerns.

RESULTS

We recruited 881 adults in exposed communities and 801 in comparison communities. We observed higher levels of self-reported psychological distress in exposed communities than in comparison communities (e.g., Katherine compared to Alice Springs, Northern Territory: clinically-significant anxiety scores, adjusted PR = 2.82, 95 % CI 1.16-6.89). We found little evidence to suggest that psychological distress was associated with PFAS serum concentrations (e.g., Katherine, PFOS and anxiety, adjusted PR = 0.85, 95 % CI 0.65-1.10). Psychological distress was higher among exposed participants who were occupationally exposed to firefighting foam, used bore water on their properties, or were concerned about their health.

CONCLUSION

Psychological distress was substantially more prevalent in exposed communities than in comparison communities. Our findings suggest that the perception of risks to health, rather than PFAS exposure, contribute to psychological distress in communities with PFAS contamination.

Mapping tuberculosis prevalence in Ethiopia using geospatial meta-analysis

BACKGROUND

Reliable and detailed data on the prevalence of tuberculosis (TB) with sub-national estimates are scarce in Ethiopia. We address this knowledge gap by spatially predicting the national, sub-national and local prevalence of TB, and identifying drivers of TB prevalence across the country.

METHODS

TB prevalence data were obtained from the Ethiopia national TB prevalence survey and from a comprehensive review of published reports. Geospatial covariates were obtained from publicly available sources. A random effects meta-analysis was used to estimate a pooled prevalence of TB at the national level, and model-based geostatistics were used to estimate the spatial variation of TB prevalence at sub-national and local levels. Within the MBG Plugin Framework, a logistic regression model was fitted to TB prevalence data using both fixed covariate effects and spatial random effects to identify drivers of TB and to predict the prevalence of TB.

RESULTS

The overall pooled prevalence of TB in Ethiopia was 0.19% [95% confidence intervals (CI): 0.12%-0.28%]. There was a high degree of heterogeneity in the prevalence of TB (I2 96.4%, P <0.001), which varied by geographical locations, data collection periods and diagnostic methods. The highest prevalence of TB was observed in Dire Dawa (0.96%), Gambela (0.88%), Somali (0.42%), Addis Ababa (0.28%) and Afar (0.24%) regions. Nationally, there was a decline in TB prevalence from 0.18% in 2001 to 0.04% in 2009. However, prevalence increased back to 0.29% in 2014. Substantial spatial variation of TB prevalence was observed at a regional level, with a higher prevalence observed in the border regions, and at a local level within regions. The spatial distribution of TB prevalence was positively associated with population density.

CONCLUSION

The results of this study showed that TB prevalence varied substantially at sub-national and local levels in Ethiopia. Spatial patterns were associated with population density. These results suggest that targeted interventions in high-risk areas may reduce the burden of TB in Ethiopia and additional data collection would be required to make further inferences on TB prevalence in areas that lack data.

Model validation for a knowledge and practices survey towards prevention of soil-transmitted helminth infections in rural villages in Indonesia

The rate of soil-transmitted helminth (STH) infection is estimated to be around 20% in Indonesia. Health promotion and health education are cost-effective strategies to supplement STH prevention and control programs. Existing studies suggest that quantitative tools for knowledge, attitudes and practices (KAP) are important to monitor effective community-based STH interventions. However, evidence is limited regarding the applicability of such tools. This study aims to identify the socio-demographic predictors for STH-related knowledge and practices and validate the quantitative tools in population use. A cross-sectional study design was conducted among residents of 16 villages in Central Java, Indonesia. Adult and child respondents were interviewed to assess general knowledge and practices in relation to STH. Two mixed effects models identified the significant factors in predicting knowledge and practice scores. The model predicted knowledge and practice scores were compared with the observed scores to validate the quantitative measurements developed in this study. Participants' socio-demographic variables were significant in predicting an individual's STH-related knowledge level and their hand washing and hygiene practices, taking into account household-level variability. Model validation results confirmed that the quantitative measurement tools were suitable for assessing STH associated knowledge and behaviour. The questionnaire developed in this study can be used to support school- and community-based health education interventions to maximize the effect of STH prevention and control programs.

Protocol for a systematic review of long-term physical sequelae and financial burden of multidrug-resistant and extensively drug-resistant tuberculosis

INTRODUCTION

Multidrug resistant (MDR) and extensively drug-resistant (XDR) tuberculosis (TB) are major public health threats that are significant causes of physical sequelae and financial consequences for infected people. Treatment for MDR- and XDR-TB are more toxic and take longer duration than for drug-susceptible-TB. As a result, the long-term sequelae are thought to be more common among patients with MDR- and XDR-TB than drug-susceptible-TB, but this is yet to be quantified. Hence, the aim of this systematic review and meta-analysis is to quantify the global burden and types of long-term physical sequelae and financial burden associated with both MDR- and XDR-TB.

METHOD AND ANALYSIS

We will search CINHAL, MEDLINE, Embase, Scopus, and Web of science for studies that report physical and financial sequelae associated with rifampicin-resistant (RR), MDR- and XDR-TB or their treatments. The search will be conducted without time, language, and place restrictions. A random-effects meta-analysis will be conducted to estimate the pooled prevalence of each physical sequela. Heterogeneity will be measured using the Higgins I2 statistics. We will assess publication bias visually using the funnel plot and statistically using Egger's test. Adjustments for publication basis will be made using Tweedie's and Duval Trim and Fill analysis.

ETHICS AND DISSEMINATION

Since the study is based on published evidence, ethics approval is not required. The findings of the systematic review will be presented at various conferences and will be published in a peer-reviewed journal.

PROTOCOL REGISTRATION

The protocol is published in the PROSPERO with registration number CRD42021250909.

Traditional Beliefs, Practices, and Migration: A Risk to Malaria Transmission in Rural Nepal

The study aimed to explore sociocultural factors influencing the risk of malaria and practices and beliefs towards malaria prevention, transmission and treatment in a remote village in Khatyad Rural Municipality (KRM) of Nepal. A sequential exploratory mixed methods approach was used. Qualitative data were collected through 25 one-on-one, in-depth interviews followed by a face-to-face household survey (n = 218) among people from a village in KRM believed to have a high risk of malaria. Traditional practices such as Chhaupadi requiring the seclusion of women during menstruation and post-partum, transhumance, and reliance on traditional healers for the management of malaria were common practices in the village. The household survey found 98.1% of women faced menstrual exile either inside the house or in a separate hut, with 64.2% not having access to Long-lasting Insecticidal Nets (LLINs). Hardships and economic constraints compelled villagers to migrate seasonally for work to malaria-endemic areas in India, thereby exposing themselves to the risk of malaria. Persistent traditional beliefs and seasonal migration could threaten the elimination goals set by the national malaria program.

A review of malaria epidemiology and control in Papua New Guinea 1900 to 2021: Progress made and future directions

The research and control of malaria has a long history in Papua New Guinea, sometimes resulting in substantial changes to the distribution of infection and transmission dynamics in the country. There have been four major periods of malaria control in PNG, with the current control programme having commenced in 2004. Each previous control programme was successful in reducing malaria burden in the country, but multiple factors led to programme failures and eventual breakdown. A comprehensive review of the literature dating from 1900 to 2021 was undertaken to summarize control strategies, epidemiology, vector ecology and environmental drivers of malaria transmission in PNG. Evaluations of historical control programs reveal poor planning and communication, and difficulty in sustaining financial investment once malaria burden had decreased as common themes in the breakdown of previous programs. Success of current and future malaria control programs in PNG is contingent on adequate planning and management of control programs, effective communication and engagement with at-risk populations, and cohesive targeted approaches to sub-national and national control and elimination.

Spatial Analysis of Schistosomiasis in Hunan and Jiangxi Provinces in the People's Republic of China

Understanding the spatial distribution of schistosome infection is critical for tailoring preventive measures to control and eliminate schistosomiasis. This study used spatial analysis to determine risk factors that may impact Schistosoma japonicum infection and predict risk in Hunan and Jiangxi Provinces in the People's Republic of China. The study employed survey data collected in Hunan and Jiangxi in 2016. Independent variable data were obtained from publicly available sources. Bayesian-based geostatistics was used to build models with covariate fixed effects and spatial random effects to identify factors associated with the spatial distribution of infection. Prevalence of schistosomiasis was higher in Hunan (12.8%) than Jiangxi (2.6%). Spatial distribution of schistosomiasis varied at pixel level (0.1 × 0.1 km), and was significantly associated with distance to nearest waterbody (km, β = -1.158; 95% credible interval [CrI]: -2.104, -0.116) in Hunan and temperature (°C, β = -4.359; 95% CrI: -9.641, -0.055) in Jiangxi. The spatial distribution of schistosomiasis in Hunan and Jiangxi varied substantially and was significantly associated with distance to nearest waterbody. Prevalence of schistosomiasis decreased with increasing distance to nearest waterbody in Hunan, indicating that schistosomiasis control should target individuals in close proximity to open water sources as they are at highest risk of infection.

Impact of a 5-Year Mass Drug Administration Programme for Soil-Transmitted Helminthiases on the Spatial Distribution of Childhood Anaemia in Burundi from 2007 to 2011

Background: Childhood anaemia affects 1.8 billion people globally. Little is known about the long-term impact of mass drug administration (MDA) for the control of soil-transmitted helminthiases (STH) on the spatiotemporal variation of anaemia prevalence and severity. We describe the long-term spatiotemporal impact of a 5-year STH MDA programme (2007−2011) on the prevalence of anaemia and anaemia severity in school-aged children (SAC) in Burundi. Methodology/Principal Findings: We used annual haemoglobin concentration and STH data collected during 2007−2011 in 31 schools in Burundi. Spatial dependence in prevalence and severity of anaemia was assessed using semivariograms. Bayesian geostatistical models were developed to (a) quantify the role of STH (adjusted for other anaemia determinants) in the spatiotemporal distribution of anaemia prevalence/severity, and (b) predict the geographical variation of both outcomes across Burundi. Adjusted population data were used to estimate the geographical distribution of the number of SAC at risk of anaemia and with low and moderate/severe anaemia. Infections with Ascaris lumbricoides and Trichuris trichiura were positively and significantly associated with childhood anaemia; hookworm infections were not. A significant decrease in anaemia prevalence, from 40−50% (2008) to 10−20% (2011) was predicted in western areas. The predicted prevalence of low-severity anaemia decreased from 40−50% (2008) to <20% (2011) in southern and eastern areas. Moderate/high-severity anaemia was concentrated in western regions of Burundi, with pockets of moderate/high-severity anaemia in central and northern regions in 2008. The overall number of predicted anaemic children decreased from 443,657 (2008) to 232,304 (2011), with a resurgence after MDA disruption in 2010 (to 480,605). Prevalence of low- and moderate-severity anaemia was higher in boys than in girls. Conclusions/Significance: Despite ongoing MDA, the prevalence of anaemia in SAC remained high and increased in certain parts of the country. It is recommended that MDA programmes targeting STH are complemented with specific anaemia interventions.

Effectiveness of public health interventions in reducing the prevalence of Opisthorchis viverrini: a protocol for systematic review and network meta-analysis

INTRODUCTION

The carcinogenic liver fluke Opisthorchis viverrini is a major public health problem in the Mekong basin region. The liver flukes can induce cholangiocarcinoma, a bile duct cancer that causes a significant burden of mortality and economic loss. Various public health interventions have been conducted to reduce opisthorchiasis but the prevalence of O. viverrini remains high in endemic regions. The aim is to quantify the effectiveness of public health interventions in reducing the prevalence of O. viverrini infection.

METHODS AND ANALYSIS

Seven databases (including PubMed, SCOPUS, Web of Science, EMBASE, ScienceDirect, Thai thesis database and TCI (Thai journals online)) will be searched from initiation through to 2022 to identify studies of interventions to reduce the prevalence of O. viverrini infection. The prevalence, incidence or number of O. viverrini-infected people will be used as the source of O. viverrini prevalence data. A conventional meta-analysis and a Bayesian network meta-analysis will be conducted to undertake direct and indirect comparisons of different interventions. Meta-regression will be used to determine the effect of each intervention. The risk of bias will be assessed using the Cochrane Collaboration's risk of bias tool. Heterogeneity between studies will be determined by forest plots and I2 and publication bias investigated with funnel plots and the Egger's test.

ETHICS AND DISSEMINATION

Ethical approval will not be required because this study will only use published data. The final report of this review will be disseminated through publication in a peer-reviewed scientific journal and will also be presented at relevant conferences.

PROSPERO REGISTRATION NUMBER

CRD42022323066.

Treatment Outcomes Among Pregnant Patients With Multidrug-Resistant Tuberculosis: A Systematic Review and Meta-analysis

IMPORTANCE

The management of multidrug-resistant tuberculosis (MDR-TB) during pregnancy is challenging, yet no systematic synthesis of evidence has accurately measured treatment outcomes.

OBJECTIVE

To systematically synthesize treatment outcomes and adverse events among pregnant patients with MDR-TB.

DATA SOURCES

PubMed, Scopus, Web of Science, and ProQuest were searched from the inception of each database through August 31, 2021.

STUDY SELECTION

Studies containing cohorts of pregnant patients with a defined treatment outcome were eligible.

DATA EXTRACTION AND SYNTHESIS

Independent reviewers screened studies and assessed the risk of bias. The study followed the Preferring Reporting Items for Systematic Review and Meta-analyses reporting guideline. Meta-analysis was performed using random-effects models. The sources of heterogeneity were explored through metaregression.

MAIN OUTCOMES AND MEASURES

The primary outcome was the proportion of patients with each treatment outcome (including treatment success, death, loss to follow-up, and treatment failure), and the secondary outcomes included the proportion of patients experiencing adverse events during pregnancy.

RESULTS

In this systematic review and meta-analysis, 10 studies containing 275 pregnant patients with available data on treatment outcomes were included. The pooled estimate was 72.5% (95% CI, 63.3%-81.0%) for treatment success, 6.8% (95% CI, 2.6%-12.4%) for death, 18.4% (95% CI, 13.1%-24.2%) for loss to follow-up, and 0.6% (95% CI, 0.0%-2.9%) for treatment failure. Treatment success was significantly higher in studies in which the proportion of patients taking linezolid was greater than the median (20.1%) compared with studies in which this proportion was lower than the median (odds ratio, 1.22; 95% CI, 1.05-1.42). More than half of the pregnant patients (54.7%; 95% CI, 43.5%-65.4%) experienced at least 1 type of adverse event, most commonly liver function impairment (30.4%; 95% CI, 17.7%-45.7%), kidney function impairment (14.9%; 95% CI, 6.2%-28.3%), hypokalemia (11.9%; 95% CI, 3.9%-25.6%), hearing loss (11.8%; 95% CI, 5.5%-21.3%), gastrointestinal disorders (11.8%; 95% CI, 5.2%-21.8%), psychiatric disorders (9.1%; 95% CI, 2.5%-21.6%), or anemia (8.9%; 95% CI, 3.6%-17.4%). The pooled proportion of favorable pregnancy outcomes was 73.2% (95% CI, 49.4%-92.1%). The most common types of adverse pregnancy outcomes were preterm birth (9.5%; 95% CI, 0.0%-29.0%), pregnancy loss (6.0%; 95% CI, 1.3%-12.9%), low birth weight (3.9%; 95% CI, 0.0%-18.7%), and stillbirth (1.9%; 95% CI, 0.1%-5.1%). Most of the studies had low-quality (3 studies) or medium-quality (4 studies) scores.

CONCLUSIONS AND RELEVANCE

In this systematic review and meta-analysis, high treatment success and favorable pregnancy outcomes were reported among pregnant patients with MDR-TB. Further research is needed to design shorter, more effective, and safer treatment regimens for pregnant patients with MDR-TB.

A qualitative study of knowledge, attitudes and perceptions towards malaria prevention among people living in rural upper river valleys of Nepal

BACKGROUND

Nepal has made significant progress in decreasing the number of malaria cases over the last two decades. Prevention and timely management of malaria are critical for the National Malaria Program in its quest for elimination. The study aimed to explore the knowledge, attitudes and behaviour towards malaria prevention and treatment among people living in rural villages of Khatyad Rural Municipality in Nepal.

METHODS

This qualitative study collected information through virtual in-depth interviews (N = 25) with female and male participants aged between 15 and 72 years.

RESULTS

More than half of the participants knew about the causes of malaria, were aware of the complications of untreated malaria and knew that anti-malarial medicines were provided for free at the public health facilities. Participants indicated that their first choice of health care were public health facilities, however limited supply of medications and diagnostics deviated patients to the private sector. While tertiary care costs were not financially viable, participants opted against traditional care for malaria. Factors such as cost of treatment, distance to the health facility and the decision making authority in households influenced health related decisions in the family. Although long-lasting insecticidal nets were distributed and indoor residual spraying was done periodically, several barriers were identified.

CONCLUSION

Increased awareness of malaria prevention and treatment among people living in malaria risk areas is important for the National Malaria Program in its quest for malaria elimination in Nepal.

High prevalence of soil-transmitted helminth infections in Myanmar schoolchildren

Background

Achieving the elimination of soil-transmitted helminth (STH) infections requires a sufficient understanding of the current epidemiological status of STH endemicity. We aimed to examine the status of STH in Myanmar – a country with the eighth highest STH prevalence in the world, 10 years after instigation of the national deworming programme.

Methods

In August 2016 we screened for STH infections using Kato Katz (KK) microscopy and real-time PCR (qPCR) in schoolchildren from the Bago Region township of Phyu, a STH sentinel site in Myanmar. Ten schools were randomly selected, and one stool sample each from a total of 264 students was examined. Prevalence and intensity of infection were calculated for each STH.

Results

High prevalence of STH was identified in the study area with 78.8% of the schoolchildren infected with at least one STH by qPCR, and 33.3% by KK. The most prevalent STH was Trichuris trichiura, diagnosed by both KK (26.1%) and qPCR (67.1%), followed by Ascaris lumbricoides (15.5% KK; 54.9% qPCR). No hookworm infections were identified by KK; however, the qPCR analysis showed a high prevalence of Ancylostoma sp. infection (29.6%) with few Necator americanus (1.1%) infections.

Conclusions

Despite bi-annual deworming of schoolchildren in the fourth-grade and below, STH prevalence remains stubbornly high. These results informed the expansion of the Myanmar National STH control programme to include all school-aged children by the Ministry of Health and Sports in 2017, however further expansion to the whole community should be considered along with improving sanitation and hygiene measures. This would be augmented by rigorous monitoring and evaluation, including national prevalence surveys.

Spatial codistribution of HIV, tuberculosis and malaria in Ethiopia

Background

HIV, tuberculosis (TB) and malaria are the three most important infectious diseases in Ethiopia, and sub-Saharan Africa. Understanding the spatial codistribution of these diseases is critical for designing geographically targeted and integrated disease control programmes. This study investigated the spatial overlap and drivers of HIV, TB and malaria prevalence in Ethiopia.

Methods

HIV, TB and malaria data were obtained from different nationwide prevalence surveys, and geospatial covariates were obtained from publicly available sources. A Bayesian model-based geostatistical framework was applied to each survey leveraging the strength of high-resolution spatial covariates to predict continuous disease-specific prevalence surfaces and their codistribution.

Results

The national prevalence was 1.54% (95% CI 1.40 to 1.70) for HIV, 0.39% (95% CI 0.34 to 0.45) for TB and 1.1% (95%CI 0.95 to 1.32) for malaria. Substantial subnational variation was predicted with the highest HIV prevalence estimated in Gambela (4.52%), Addis Ababa (3.52%) and Dire Dawa (2.67%) regions. TB prevalence was highest in Dire Dawa (0.96%) and Gambela (0.88%), while malaria was highest in Gambela (6.1%) and Benishangul-Gumuz (3.8%). Spatial overlap of their prevalence was observed in some parts of the country, mainly Gambela region. Spatial distribution of the diseases was significantly associated with healthcare access, demographic, and climatic factors.

Conclusions

The national distribution of HIV, TB and malaria was highly focal in Ethiopia, with substantial variation at subnational and local levels. Spatial distribution of the diseases was significantly associated with healthcare access, demographic and climatic factors. Spatial overlap of HIV, TB and malaria prevalence was observed in some parts of the country. Integrated control programmes for these diseases should be targeted to these areas with high levels of co-endemicity.

Schistosomiasis in the People's Republic of China - down but not out

Schistosomiasis has been subjected to extensive control efforts in the People's Republic of China (China) which aims to eliminate the disease by 2030. We describe baseline results of a longitudinal cohort study undertaken in the Dongting and Poyang lakes areas of central China designed to determine the prevalence of Schistosoma japonicum in humans, animals (goats and bovines) and Oncomelania snails utilizing molecular diagnostics procedures. Data from the Chinese National Schistosomiasis Control Programme (CNSCP) were compared with the molecular results obtained.Sixteen villages from Hunan and Jiangxi provinces were surveyed; animals were only found in Hunan. The prevalence of schistosomiasis in humans was 1.8% in Jiangxi and 8.0% in Hunan determined by real-time polymerase chain reaction (PCR), while 18.3% of animals were positive by digital droplet PCR. The CNSCP data indicated that all villages harboured S. japonicum-infected individuals, detected serologically by indirect haemagglutination assay (IHA), but very few, if any, of these were subsequently positive by Kato-Katz (KK).Based on the outcome of the IHA and KK results, the CNSCP incorporates targeted human praziquantel chemotherapy but this approach can miss some infections as evidenced by the results reported here. Sensitive molecular diagnostics can play a key role in the elimination of schistosomiasis in China and inform control measures allowing for a more systematic approach to treatment.

The impact of ethnic minority status on tuberculosis diagnosis and treatment delays in Hunan Province, China

BACKGROUND

Tuberculosis (TB) continues to be a major public health challenge in China. Understanding TB management delays within the context of China's unique ethnic diversity may be of value in tackling the disease. This study sought to evaluate the impact of ethnic minority status on TB diagnosis and treatment delays.

METHODS

This retrospective cohort study was conducted on patients diagnosed with TB in Hunan Province, China between 2013 and 2018. Diagnosis delay was defined as the time interval between the onset of symptoms and the date of diagnosis. Treatment delay was defined as the time interval between diagnosis and treatment commencement. Univariable and multivariable logistic regression models were used to identify factors associated with TB diagnosis and treatment delay, including ethnic minority status. Adjusted odds ratios (AOR) with 95% confidence intervals (CI) were calculated to assess the strength of association between the dependant and independent variables.

RESULTS

A total of 318,792 TB patients were included in the study with a mean age of 51.7 years (SD 17.7). The majority of patients were male (72.6%) and Han ethnicity (90.6%). The odds of experiencing diagnosis delay (> 21 days) were significantly higher for Tujia (AOR: 1.46, 95% CI: 1.41, 1.51), Miao (AOR: 1.31, 95% CI: 1.26, 1.37), Dong (AOR: 1.97, 95% CI: 1.85, 2.11), Yao (AOR: 1.27, 95% CI: 1.17, 1.37), and Bai (AOR: 1.45, 95% CI: 1.22, 1.74) ethnic minorities compared to the Han majority. The odds of experiencing treatment delay (> 15 days) were significantly lower for five of the seven ethnic minority groups relative to the Han majority: Tujia (AOR 0.92, 95% CI 0.88, 0.96), Miao (AOR 0.74, 95% CI 0.70, 0.79), Dong (AOR 0.87, 95% CI 0.81, 0.95), Yao (AOR 0.20, 95% CI 0.17, 0.24) and 'other' (ethnic minorities that individually represented < 0.1% of the patient population) (AOR 0.70, 955 CI 0.51, 0.97).

CONCLUSIONS

This study shows ethnic minority status to be a significant risk factor in diagnosis delay, but for it to reduce the odds of treatment delay. Further research is required to determine the underlying causes of diagnosis delay within ethnic minority populations.

"The Magic Glasses Philippines": a cluster randomised controlled trial of a health education package for the prevention of intestinal worm infections in schoolchildren

Background

Soil-transmitted helminths (STH) cause substantial disease and disability globally. Health education has proven complementary to school-based drug administration programs for STH control. We determined the generalizability of the impact of "The Magic Glasses" health education package for STH prevention in schoolchildren in Laguna province, the Philippines, having previously shown its positive impact in China.

Methods

We conducted a cluster-randomised controlled trial, in schoolchildren, aged 9-10 years, across 40 schools over one year. Schools were randomly assigned either to the "Magic Glasses Philippines" health education intervention package (consisting of a cartoon video, classroom discussions, drawing and essay competition) complementing the standard health education activities of the Philippines Departments of Health and Education, or to a control group, which involved only the standard health education activities. The primary trial outcomes were the proportion of STH infected schoolchildren and their knowledge, attitude and behaviour of STH assessed in both groups at baseline and through two follow-up surveys undertaken immediately prior to the semi-annual national mass administration of albendazole. The outcomes between the study arms were compared using generalized estimating equation models, accounting for clustering at the school level. The trial is registered with Australian New Zealand Clinical Trials Registry number: ACTRN12616000508471.

Findings

At follow-up assessments, the mean knowledge and behaviour scores in the intervention group were, respectively, 5·3 (95% confidence interval [CI]:4·2-6·5; p=<0.001) and 1·1 (95% CI: 0·4-1·7; p=0.002) percentage points higher than the control group. There was no overall effect on helminth infections (any STH; adjusted odds ratio [aOR]:1·0; 95% CI: 0·8-1·3; p=0·856), Ascaris lumbricoides; aOR:1·0; 95% CI: 0·7-1·6; p=0·894, or Trichuris trichiura; aOR:1·7; 95% CI: 0·9-1·6; p=0·315) but sub-group analysis showed a 60% reduction in the odds of any STH infection resulting from the "Magic Glasses" intervention in schools with a baseline prevalence ≤15% (aOR: 0·4; 95% CI: 0·2-0·7; p=0·001).

Interpretation

The health-education package demonstrated a modest but statistically significant impact on the students' overall STH knowledge and changes in their behaviour but was only effective in preventing STH infections in intervention schools where the baseline prevalence was ≤15%.

Funding

National Health and Medical Research Council, Australia, and the UBS-Optimus Foundation, Switzerland.

Risk factors associated with unsuccessful tuberculosis treatment outcomes in Hunan Province, China

OBJECTIVES

Globally, China has the third highest number of tuberculosis (TB) cases despite high rates (85.6%) of effective treatment coverage. Identifying risk factors associated with unsuccessful treatment outcomes is an important component of maximizing the efficacy of TB control programs.

METHODS

Retrospective cohort study to evaluate the outcomes of 306,860 drug-susceptible TB patients who underwent treatment in Hunan Province, China between 2013 and 2018. Univariable and multivariable logistic regression models were used to identify factors associated with unsuccessful TB treatment outcomes.

RESULTS

A successful treatment outcome was recorded for 98.6% of patients, defined as the sum of patients who were cured (36.2%) and completed treatment (62.4%). An unsuccessful treatment outcome was recorded for 1.8% of patients, defined as the sum of treatment failure (1.1%), deaths (0.5%) and lost to follow up (0.2%). The odds of an unsuccessful treatment outcome showed an increasing trend in more recent years of registration (2018 Adjusted Odds Ratio (AOR): 1.43; 95% Confidence Interval (CI) 1.31, 1.57 relative to 2013). Other significant risk factors were male sex (AOR: 1.17; 95% CI 1.10, 1.25); increasing age (AOR:1.02 per year increase; 95% CI 1.02,1.02); being severely ill (AOR: 1.50; 95% CI 1.33, 1.70); having a history of TB treatment (AOR: 2.93; 95% CI 2.69, 3.20); not being under systematic management (AOR: 16.10 (14.49, 17.88) and treatment regimens that differed from full course management.

CONCLUSIONS

The increasing likelihood of an unsuccessful treatment outcome over time necessitates the need for further research.

The COVID-19 vaccination campaign in Bhutan: strategy and enablers

Bhutan has reported a total of 2596 COVID-19 cases and three deaths as of September 15, 2021. With support from India, the United States, Denmark, the People's Republic of China, Croatia and other countries, Bhutan was able to conduct two rounds of nationwide vaccination campaign. While many countries struggle to overcome vaccine refusal or hesitancy due to complacency, a lack of trust, inconvenience and fear, escalated in some countries by anti-vaccine groups, Bhutan managed to inoculate more than 95% of its eligible populations in two rounds of vaccination campaign. Enabling factors of this successful vaccination campaign were strong national leadership, a well-coordinated national preparedness plan, and high acceptability of vaccine due to effective mass communication and social engagement led by religious figures, volunteers and local leaders. In this short report, we described the national strategic plan and enabling factors that led to the success of this historical vaccination campaign.

Soil-transmitted helminth infections and nutritional indices among Filipino schoolchildren

BACKGROUND

Soil-transmitted helminth (STH) infections are still prevalent among schoolchildren in the Philippines. We evaluated the risk factors associated with STH and the relationship between STH and nutritional indices among schoolchildren aged 9-10 years in Laguna province, the Philippines.

METHODS

We used the baseline data from 40 schools enrolled in a randomised controlled trial of the Magic Glasses Philippines health education package. Data on demographic and socio-economic variables, and STH related knowledge, attitudes and practices, were obtained through a questionnaire. Stool samples were collected and assessed for STH egg presence using the Kato-Katz technique. Haemoglobin levels and height and weight of study participants were also determined. The generalized estimating equations approach was used to construct logistic regression models to assess STH-associated risk factors, and the association between any STH infection and anaemia, child stunting, wasting and being underweight. The trial is registered with the Australian New Zealand Clinical Trials Registry (ACTRN12616000508471).

FINDINGS

Among 1,689 schoolchildren, the prevalence of any STH was 23%. The prevalence of anaemia, stunting, being underweight and wasting was 13%, 20.2%, 19% and 9.5%, respectively. Age, socio-economic status, rural/urban classification of schools and knowledge of STH were significant risk factors for acquiring a STH infection. Moreover, infections with any STH were significantly associated with stunting (P = <0.001) and being underweight (P = <0.003), but not wasting (P = 0.375) or anaemia (P = 0.462) after controlling for confounding covariates.

CONCLUSION

The study findings emphasise the need for sustainable deworming in tandem with other measures such as the provision of health education, improvements in sanitation and hygiene, and nutritional programs in order to control STH infections and improve morbidity outcomes in schoolchildren.

TRIAL REGISTRATION

Australian New Zealand Clinical Trials Registry (ACTRN12616000508471).

Opisthorchis viverrini and Strongyloides stercoralis mono- and co-infections: Bayesian geostatistical analysis in an endemic area, Thailand

Parasitic infections caused by Opisthorchis viverrini and Strongyloides stercoralis remain a major public health threat in the Greater Mekong Sub-region. An understanding of climate and other environmental influences on the geographical distribution and emergence of parasitic diseases is a crucial step to guide targeted control and prevention programs. A parasitological survey was conducted from 2008 to 2013 and included 12,554 individuals (age between 20 and 60 years) from 142 villages in five districts in Khon Kaen Province, Thailand. Geographical information systems, remote sensing technologies and a Bayesian geostatistical framework were used to develop models for O. viverrini and S. stercoralis mono- and co-infections in areas where both parasites are known to co-occur. The results indicate that male sex, increased age, altitude, precipitation, and land surface temperature have influenced the infection rate and geographical distribution of mono- and co-infections of O. viverrini and S. stercoralis in this area. Males were 6.69 times (95% CrI: 5.26-8.58) more likely to have O. viverrini - S. stercoralis co-infection. We observed that O. viverrini and S. stercoralis mono-infections display distinct spatial pattern, while co-infection is predicted in the center and southeast of the study area. The observed spatial clustering of O. viverrini and S. stercoralis provides valuable information for the spatial targeting of prevention interventions in this area.

The prevalence of soil transmitted helminth infections in minority indigenous populations of South-East Asia and the Western Pacific Region: A systematic review and meta-analysis

INTRODUCTION

Soil transmitted helminth (STH) infections cause one of the most prevalent diseases in man. STHs disproportionately impact socio-economically disadvantaged communities including minority indigenous populations. This systematic review aimed to quantify the prevalence of STH infection within minority indigenous populations of the South-East Asia and Western Pacific Regions.

METHODS

The systematic review was conducted in accordance with The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines following a published protocol. A random effects meta-analysis was used to estimate the pooled prevalence of STH infection, and meta-regression analysis was used to quantify associations with study characteristics. Where comparative data were available, sub-group analysis was conducted to evaluate the risk of STH infection in minority indigenous people relative to other population groups. The heterogeneity between studies was evaluated visually using Forest plots and was assessed quantitatively by the index of heterogeneity (I2) and Cochran Q-statistics.

RESULTS

From 1,366 unique studies that were identified, 81 were included in the final analysis. The pooled prevalence of infection within minority indigenous populations was 61.4% (95% CI 50.8, 71.4) for overall STH infection; 32.3% (95% CI 25.7, 39.3) for Ascaris.lumbricoides; 43.6% (95% CI 32.6, 54.8) for Trichuris.trichiura; 19.9% (95% CI 15.7, 24.5) for hookworm and 6.3% (95% CI 3.2, 10.2) for Strongyloides.stercoralis. A significant increase in T. trichiura prevalence was observed over time. The stratified analysis showed that the prevalence of infection for STH overall and for each STH species were not significantly different in minority indigenous participants compared to other populations groups.

CONCLUSION

The prevalence of STH infection is high within minority indigenous populations across countries at very different levels of socio-economic development. The increasing prevalence of T. trichiura calls for the implementation of more effective therapies and control strategies.

Spatio-temporal patterns of childhood pneumonia in Bhutan: a Bayesian analysis

Pneumonia is one of the top 10 diseases by morbidity in Bhutan. This study aimed to investigate the spatial and temporal trends and risk factors of childhood pneumonia in Bhutan. A multivariable Zero-inflated Poisson regression model using a Bayesian Markov chain Monte Carlo simulation was undertaken to quantify associations of age, sex, altitude, rainfall, maximum temperature and relative humidity with monthly pneumonia incidence and to identify the underlying spatial structure of the data. Overall childhood pneumonia incidence was 143.57 and 10.01 per 1000 persons over 108 months of observation in children aged < 5 years and 5–14 years, respectively. Children < 5 years or male sex were more likely to develop pneumonia than those 5–14 years and females. Each 1 °C increase in maximum temperature was associated with a 1.3% (95% (credible interval [CrI] 1.27%, 1.4%) increase in pneumonia cases. Each 10% increase in relative humidity was associated with a 1.2% (95% CrI 1.1%, 1.4%) reduction in the incidence of pneumonia. Pneumonia decreased by 0.3% (CrI 0.26%, 0.34%) every month. There was no statistical spatial clustering after accounting for the covariates. Seasonality and spatial heterogeneity can partly be explained by the association of pneumonia risk to climatic factors including maximum temperature and relative humidity.

Clinical predictors of severe dengue: a systematic review and meta-analysis

Background

Severe dengue is a life-threatening complication; rapid identification of these cases, followed by adequate management is crucial to improve the clinical prognosis. Therefore, this study aimed to identify risk factors and predictors of severe dengue.

Methods

A literature search for studies reporting risk factors of severe dengue among individuals with dengue virus infection was conducted in PubMed, Scopus and Web of Science database from inception to December 31, 2020. Pooled odds ratios (ORs) for patients’ demographic characteristics, co-morbidities, and warning signs were estimated using an inverse variance heterogeneity model.

Results

We included 143 articles in the meta-analysis from a total of 13 090 articles retrieved from the literature search. The risk factors of severe dengue were: being a child [OR = 1.96; 95% confidence interval (CI): 1.22–3.13], secondary infection (OR = 3.23; 95% CI: 2.28–4.57), and patients with pre-existing diabetes (OR = 2.88; 95% CI: 1.72–4.81) and renal disease (OR = 4.54; 95% CI: 1.55–13.31). Warning signs strongly associated with severe disease were increased haematocrit with a concurrent decrease in platelet count (OR = 5.13; 95% CI: 1.61–16.34), abdominal pain (OR = 2.00; 95% CI: 1.49–2.68), lethargy (OR = 2.73; 95% CI: 1.05–7.10), vomiting (OR = 1.80; 95% CI: 1.43–2.26), hepatomegaly (OR = 5.92; 95% CI: 3.29–10.66), ascites (OR = 6.30; 95% CI: 3.75–10.60), pleural effusion (OR = 5.72; 95% CI: 3.24–10.10) and melena (OR = 4.05; 95% CI: 1.64–10.00).

Conclusions

Our meta-analysis identified children, secondary infection, diabetes and renal disease(s) as important predictors of severe dengue. Our finding also supports the predictive ability of the WHO warning signs to identify severe dengue. These findings are useful for clinicians to identify severe dengue for management and timely interventions.

Supplementary Information

The online version contains supplementary material available at 10.1186/s40249-021-00908-2.

Community engagement approaches for malaria prevention, control and elimination: a scoping review protocol

Community engagement (CE) is important for malaria prevention, control and ultimately elimination. As the decline of malaria has plateaued over the last 5 years, strengthening CE approaches will be necessary to enhance health promotion practice and policy to drive malaria transmission down further. Countries have adopted a wide range of public health intervention approaches for malaria prevention and control that best suit their context. This review will examine the existing evidence on the various CE approaches adopted by malaria programmes across the world and their outcomes. METHODOLOGY AND ANALYSIS: The review methodology will follow the updated Joanna Briggs Institute guide for scoping review, 2017, which is based on the framework developed by Arksey and O'Malley and further developed by Levac Colquhoun and O'Brien. Proquest, Web of Knowledge and Medline will be searched for publications from January 2000 to 31 March 2021 while Google search engine will be used to find any grey literature. The eligibility criteria will be as follows: review will include primary studies written in the English language using appropriate study designs and methods, including quantitative, qualitative and mixed methods designs; and case, programme or project reports. Information on CE approaches designed specifically for malaria prevention, control, elimination and their outcomes will be explored. Subheadings and free text terms for 'community engagement' and 'malaria' will be used for the search. The article screening and data extraction will be examined by two reviewers after the initial search, and any disputes will be resolved by a third reviewer through discussion. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension for scoping reviews guide will be used to present the review methods and the results from the search. The scoping review results will identify and map the available evidences, sources of information and research gaps in the area of CE as one approach for malaria prevention, control and/or elimination. ETHICS AND DISSEMINATION: This study only aims to review secondary sources and does not require human research ethics committee approval. The findings of the scoping review will be submitted to a peer-reviewed journal for wider dissemination.

Medical practitioner's knowledge on dengue management and clinical practices in Bhutan

Background

Dengue has emerged as a major public health problem in Bhutan, with increasing incidence and widening geographic spread over recent years. This study aimed to investigate the knowledge and clinical management of dengue among medical practitioners in Bhutan.

Methods

We administered a survey questionnaire to all practitioners currently registered under the Bhutan Medical and Health Council. The questionnaire contained items on four domains including transmission, clinical course and presentation, diagnosis and management, and surveillance and prevention of dengue. Participants were able to respond using an online Qualtrics survey, with the invitation and link distributed via email.

Results

A total of 97 respondents were included in the study (response rate: 12.7%), of which 61.86% were Health Assistants/Clinical Officers (HAs/COs) and 38.14% were medical doctors. The afternoon feeding behaviour of Aedes mosquito was correctly identified by only 24.7% of the respondents, and ~66.0% of them failed to identify lethargy as a warning sign for severe dengue. Knowledge on diagnosis using NS1 antigen and the clinical significance of elevated haematocrit for initial fluid replacement was strikingly low at 47.4% and 27.8% respectively. Despite dengue being a nationally notifiable disease, ~60% of respondents were not knowledgeable on the timing and type of cases to be reported. Respondent’s median score was higher for the surveillance and reporting domain, followed by their knowledge on transmission of dengue. Statistically significant factors associated with higher knowledge included respondents being a medical doctor, working in a hospital and experience of having diagnosed dengue.

Conclusion

The study revealed major gaps on knowledge and clinical management practices related to dengue in Bhutan. Physicians and health workers working in Basic Health Units need training and regular supervision to improve their knowledge on the care of dengue patients.

The prevalence of tuberculosis, malaria and soil-transmitted helminth infection in minority indigenous people of Southeast Asia and the Western Pacific: protocol for a systematic review and meta-analysis

BACKGROUND

Infectious diseases such as tuberculosis (TB), malaria and soil-transmitted helminthiasis continue to impose a significant global health burden and socio-economic impact. Globally, minority indigenous people are disproportionately affected by poverty and are shown to experience a disparate burden of disease and poorer health outcomes than the comparative majority population. Despite these inequalities, countries rarely systematically compile epidemiological data disaggregated by ethnicity to enable the extent of the differential to be quantified.

METHODS

The systematic review will be reported in accordance with The Preferred Reporting Items for Systematic Review and Meta- Analyses (PRISMA) guidelines. Systematic searches will be conducted in EMBASE, Medline, Scopus and Web of Science for studies reporting data which enable the prevalence of TB, malaria, and/or soil-transmitted helminth (STH) infections amongst minority indigenous populations within the Southeast Asia Region (SEAR) and Western Pacific Region (WPR) to be calculated. Where studies provide data on disease prevalence for both minority indigenous and other populations within the same study, a comparative analysis will be undertaken. In addition to a narrative synthesis, where sufficient data are available, a random-effects meta-analysis will be conducted to obtain a pooled estimate value for each disease/infection by country and mortality stratum. Heterogeneity between studies will be examined using the Cochran's Q test and quantitatively measured by the index of heterogeneity squared (I2) statistics. The methodological quality of the included studies will be assessed using a modified Newcastle-Ottawa Scale.

DISCUSSION

This systematic review aims to analyse the available data on the prevalence of TB, malaria and STH infections within minority indigenous populations of the SEAR and WPR.

REGISTRATION

Open Science Framework registration: osf.io/m6sqc.

Efficacy of a 3-day pretravel schedule of tafenoquine for malaria chemoprophylaxis: a network meta-analysis

BACKGROUND

Chemoprophylaxis with weekly doses of tafenoquine (200 mg/day for 3 days before departure [loading dose], 200 mg/week during travel and 1-week post-travel [maintenance doses]) is effective in preventing malaria. Effectiveness of malaria chemoprophylaxis drugs in travellers is often compromised by poor compliance. Shorter schedules that can be completed before travel, allowing 'drug-free holidays', could increase compliance and thus reduce travel-related malaria. In this meta-analysis, we examined if a loading dose of tafenoquine alone is effective in preventing malaria in short-term travellers.

METHODS

Four databases were searched in November 2020 for randomized controlled trials (RCTs) that assessed efficacy and/or safety of tafenoquine for chemoprophylaxis. Network meta-analysis using the generalized pair-wise modelling framework was utilized to estimate the odds ratio (OR) of malaria infection in long-term (>28 days) and short-term (≤28 days) travellers, as well as adverse events (AEs) associated with receiving loading dose of tafenoquine alone, loading dose of tafenoquine followed by maintenance doses, loading dose of mefloquine followed by maintenance doses, or placebo.

RESULTS

Nine RCTs (1714 participants) were included. In long-term travellers, compared to mefloquine, tafenoquine with maintenance doses (OR = 1.05; 95% confidence interval [CI]: 0.44-2.46) was equally effective in preventing malaria, while there was an increased risk of infection with the loading dose of tafenoquine alone (OR = 2.89; 95% CI: 0.78-10.68) and placebo (OR = 62.91; 95% CI: 8.53-463.88). In short-term travellers, loading dose of tafenoquine alone (OR = 0.98; 95% CI: 0.04-22.42) and tafenoquine with maintenance doses (OR = 1.00; 95% CI: 0.06-16.10) were as effective as mefloquine. The risk of AEs with tafenoquine with maintenance doses (OR = 1.03; 95% CI: 0.67-1.60) was similar to mefloquine, while loading dose of tafenoquine alone (OR = 0.58; 95% CI: 0.20-1.66) was associated with lower risk of AEs, although the difference was not statistically significant.

CONCLUSIONS

For short-term travellers, loading dose of tafenoquine alone was equally effective, had possibly lower rate of AEs, and likely better compliance than standard tafenoquine or mefloquine chemoprophylaxis schedules with maintenance doses. Studies are needed to confirm if short-term travellers remain free of infection after long-term follow-up.

REGISTRATION

The meta-analysis was registered in PROSPERO (CRD42021223756).

HIGHLIGHT

Tafenoquine is the latest approved drug for malaria chemoprophylaxis. A loading dose of tafenoquine (200 mg/day for 3 days before departure) is as effective in preventing malaria in short-term (≤28 days) travellers as chemoprophylaxis schedules of tafenoquine or mefloquine with maintenance doses, allowing travellers to have a 'drug-free holiday'.

Spatiotemporal Patterns of Tuberculosis in Hunan Province, China

Tuberculosis (TB) is the leading cause of death from a bacterial pathogen worldwide. China has the third highest TB burden in the world, with a high reported burden in Hunan Province (amongst others). This study aimed to investigate the spatial distribution of TB and identify socioeconomic, demographic, and environmental drivers in Hunan Province, China. Numbers of reported cases of TB were obtained from the Tuberculosis Control Institute of Hunan Province, China. A wide range of covariates were collected from different sources, including from the Worldclim database, and the Hunan Bureau of Statistics. These variables were summarized at the county level and linked with TB notification data. Spatial clustering of TB was explored using Moran’s I statistic and the Getis–Ord statistic. Poisson regression models were developed with a conditional autoregressive (CAR) prior structure, and with posterior parameters estimated using a Bayesian approach with Markov chain Monte Carlo (MCMC) simulation. A total of 323,340 TB cases were reported to the Hunan TB Control Institute from 2013 to 2018. The mean age of patients was 51.7 years (SD + 17.6 years). The majority of the patients were male (72.6%, n = 234,682) and had pulmonary TB (97.5%, n = 315,350). Of 319,825 TB patients with registered treatment outcomes, 306,107 (95.7%) patients had a successful treatment outcome. The annual incidence of TB decreased over time from 85.5 per 100,000 population in 2013 to 76.9 per 100,000 population in 2018. TB case numbers have shown seasonal variation, with the highest number of cases reported during the end of spring and the beginning of summer. Spatial clustering of TB incidence was observed at the county level, with hotspot areas detected in the west part of Hunan Province. The spatial clustering of TB incidence was significantly associated with low sunshine exposure (RR: 0.86; 95% CrI: 0.74, 0.96) and a low prevalence of contraceptive use (RR: 0.88; 95% CrI: 0.79, 0.98). Substantial spatial clustering and seasonality of TB incidence were observed in Hunan Province, with spatial patterns associated with environmental and health care factors. This research suggests that interventions could be more efficiently targeted at locations and times of the year with the highest transmission risk.

Epidemiology and challenges of dengue surveillance in the WHO South-East Asia Region

Dengue poses a significant health and economic burden in the WHO South-East Asia Region. Approaches for control need to be aligned with current knowledge on the epidemiology of dengue in the region. Such knowledge will ensure improved targeting of interventions to reduce dengue incidence and its socioeconomic impact. This review was undertaken to describe the contemporary epidemiology of dengue and critically analyse the existing surveillance strategies in the region. Over recent decades, dengue incidence has continued to increase with geographical expansion. The region has now become hyper-endemic for multiple dengue virus serotypes/genotypes. Every epidemic cycle was associated with a change of predominant serotype/genotype and this was often associated with severe disease with intense transmission. Classical larval indices are widely used in vector surveillance and adult mosquito samplings are not implemented as a part of routine surveillance. Further, there is a lack of integration of entomological and disease surveillance systems, often leading to inaction or delays in dengue prevention and control. Disease surveillance does not capture all cases, resulting in under-reporting, and has thus failed to adequately represent the true burden of disease in the region. Possible solutions include incorporating adult mosquito sampling into routine vector surveillance, the establishment of laboratory-based sentinel surveillance, integrated vector and dengue disease surveillance and climate-based early warning systems using available technologies like mobile apps.

Spatial prediction of malaria prevalence in Papua New Guinea: a comparison of Bayesian decision network and multivariate regression modelling approaches for improved accuracy in prevalence prediction

Background

Considerable progress towards controlling malaria has been made in Papua New Guinea through the national malaria control programme’s free distribution of long-lasting insecticidal nets, improved diagnosis with rapid diagnostic tests and improved access to artemisinin combination therapy. Predictive prevalence maps can help to inform targeted interventions and monitor changes in malaria epidemiology over time as control efforts continue. This study aims to compare the predictive performance of prevalence maps generated using Bayesian decision network (BDN) models and multilevel logistic regression models (a type of generalized linear model, GLM) in terms of malaria spatial risk prediction accuracy.

Methods

Multilevel logistic regression models and BDN models were developed using 2010/2011 malaria prevalence survey data collected from 77 randomly selected villages to determine associations of Plasmodium falciparum and Plasmodium vivax prevalence with precipitation, temperature, elevation, slope (terrain aspect), enhanced vegetation index and distance to the coast. Predictive performance of multilevel logistic regression and BDN models were compared by cross-validation methods.

Results

Prevalence of P. falciparum, based on results obtained from GLMs was significantly associated with precipitation during the 3 driest months of the year, June to August (β = 0.015; 95% CI = 0.01–0.03), whereas P. vivax infection was associated with elevation (β = − 0.26; 95% CI = − 0.38 to − 3.04), precipitation during the 3 driest months of the year (β = 0.01; 95% CI = − 0.01–0.02) and slope (β = 0.12; 95% CI = 0.05–0.19). Compared with GLM model performance, BDNs showed improved accuracy in prediction of the prevalence of P. falciparum (AUC = 0.49 versus 0.75, respectively) and P. vivax (AUC = 0.56 versus 0.74, respectively) on cross-validation.

Conclusions

BDNs provide a more flexible modelling framework than GLMs and may have a better predictive performance when developing malaria prevalence maps due to the multiple interacting factors that drive malaria prevalence in different geographical areas. When developing malaria prevalence maps, BDNs may be particularly useful in predicting prevalence where spatial variation in climate and environmental drivers of malaria transmission exists, as is the case in Papua New Guinea.

The control of soil-transmitted helminthiases in the Philippines: the story continues

Background

Soil-transmitted helminth (STH) infections have long been an important public health concern in the Philippines. In this review, we describe the current status of STH infections there and highlight the control efforts undertaken to reduce STH burden.

Main text

A nationwide STH mass drug administration (MDA) programme was started in 2006 but the overall STH prevalence remains stubbornly high across the Philippines, ranging from 24.9% to 97.4%. The continued increase in the prevalence may have been due to the challenges related to MDA implementation which include the lack of people’s awareness about the importance of regular treatment, misconceptions about the MDA strategy, lack of confidence on the drugs used, fear of adverse events and general distrust of government programs. There are existing water, sanitation and hygiene (WASH) programmes implemented in communities [e.g., Community-Led Total Sanitation (CLTS) program and providing toilet bowls and provision of subsidy for latrine construction] and schools [e.g., WASH in School (WINS) program], but sustained implementation is required to achieve expected outcomes. Although WASH in general is being taught in schools, integration of STH as a disease and community problem in the current public elementary school curriculum is still inadequate. The Integrated Helminth Control Program (IHCP) currently implemented in the country, which is focused on improved sanitation and personal hygiene, health education and preventive chemotherapy, will require continuous appraisal. The sustainability of this programme still continues to be a challenge.

Conclusions

Despite the major efforts to control STH infections for almost two decades in the Philippines, persistently high STH prevalence has been reported across the country, which is likely due to suboptimal MDA coverage and limitations in WASH and health education programs. Sustainable delivery of integrated control approaches will continue to play a pivotal role in the control and elimination of STH in the Philippines.

Graphic abstract

Spatio-Temporal Patterns of Dengue Incidence in Medan City, North Sumatera, Indonesia

Dengue has been a perennial public health problem in Medan city, North Sumatera, despite the widespread implementation of dengue control. Understanding the spatial and temporal pattern of dengue is critical for effective implementation of dengue control strategies. This study aimed to characterize the epidemiology and spatio-temporal patterns of dengue in Medan City, Indonesia. Data on dengue incidence were obtained from January 2016 to December 2019. Kulldorff’s space-time scan statistic was used to identify dengue clusters. The Getis-Ord Gi* and Anselin Local Moran’s I statistics were used for further characterisation of dengue hotspots and cold spots. Results: A total of 5556 cases were reported from 151 villages across 21 districts in Medan City. Annual incidence in villages varied from zero to 439.32 per 100,000 inhabitants. According to Kulldorf’s space-time scan statistic, the most likely cluster was located in 27 villages in the south-west of Medan between January 2016 and February 2017, with a relative risk (RR) of 2.47. Getis-Ord Gi^* and LISA statistics also identified these villages as hotpot areas. Significant space-time dengue clusters were identified during the study period. These clusters could be prioritized for resource allocation for more efficient prevention and control of dengue.