Impact of pneumococcal conjugate vaccination on pneumococcal nasopharyngeal carriage in the Gambia: Population-based cross-sectional surveys

BACKGROUND

The introduction of pneumococcal conjugate vaccines (PCV) has reduced carriage of vaccine-type (VT) pneumococci in many settings. We determined the impact of The Gambia's national PCV programme on carriage of VT pneumococci in the population.

METHODS

Seven-valent PCV (PCV7) was introduced in August 2009 without catch-up and with doses scheduled at 2, 3, 4 months of age; it was replaced by PCV13 in May 2011. We did cross-sectional carriage surveys in 2009, 2015, and 2017 in age-stratified, population-based samples. Nasopharyngeal specimens were collected and processed according to WHO guidelines. We calculated observed and adjusted prevalence ratios (PR) of VT carriage before and after PCV introduction.

FINDINGS

We enrolled 2988, 3162, and 2709 participants in 2009, 2015, and 2017 respectively. The baseline (2009) prevalence of VT pneumococcal carriage among children aged 0-4 years was 42.6 %, which declined to 14.9 % and 17.5 % in 2015 and 2017 respectively (adjPR 0.32 [95 % CI 0.27, 0.38] and 0.38 [0.31, 0.46] respectively). VT prevalence among children aged 5-14 years was 16.6 %, 15.1 %, and 15.8 % in the three surveys (2017 vs 2009, adjPR 0.70 [0.58, 0.83]). VT prevalence among 15-44 year-olds was 6.4 %, 5.7 %, and 7.1 % in the three surveys (2017 vs 2009, adjPR 0.59 [0.46, 0.75]), while in those aged ≥ 45 years it was 4.5 %, 6.5 %, and 4.5 % respectively. Non-VT carriage increased in all age-groups. Prevalent residual serotypes were 34 and 15B (age 0-4 years), 3 and 34 (age 5-14 years), and 3 and 16F (age ≥ 15 years).

CONCLUSIONS

Introduction of PCV was associated with reduced VT pneumococcal carriage in young, and older children, although with substantial residual prevalence. Persisting VT, and non-VT, carriage indicate significant, persistent transmission of pneumococci in the population.

Tuberculin skin test and Interferon-gamma release assay agreement, and associated factors with latent tuberculosis infection, in medical and nursing students in Bandung, Indonesia

BACKGROUND

No gold standard diagnostic test exists for latent tuberculosis infection (LTBI). The intra-dermal tuberculin skin test (TST) has known limitations and Interferon-gamma release assays (IGRA) have been developed as an alternative. We aimed to assess agreement between IGRA and TST, and risk factors for test positivity, in Indonesian healthcare students.

METHODS

Medical and nursing students starting their clinical training were screened using IGRA and TST. Agreement between the two tests was measured using Cohen's Kappa coefficient. Logistic regression was used to identify factors associated with test positivity.

RESULTS

Of 266 students, 43 (16.2%) were IGRA positive and 85 (31.9%) TST positive. Agreement between the two tests was 74.7% (kappa 0.33, 95% CI 0.21-0.45, P<0.0001). Students who had direct contact with family or friends with TB were less likely to be test positive using IGRA (AOR 0.18, 95% CI 0.05-0.64) and using TST (AOR 0.51, 95% CI 0.26-0.99).

CONCLUSION

Test positivity for LTBI was lower when measured by IGRA than by TST, with poor agreement between the two tests. Known close TB contact was unexpectedly negatively associated with positivity by either test. Longitudinal studies may be required to help determine the best test for LTBI in healthcare students in Indonesia.

Selective under-representation of Pacific peoples in population estimates for health indicator measurements in Aotearoa New Zealand misinforms policy making

BACKGROUND

The Census of Populations and Dwellings' is the five yearly population count of Aotearoa New Zealand. Best available populations (BAP) are subnational projections based on census data and demographic assumptions developed for healthcare planning and funding allocation but are also used as the denominator for health indicator monitoring. Pacific people are systematically undercounted, but the impact on health statistics is not well studied. For COVID-19 vaccination coverage, health service user (HSU) data were considered a more reliable denominator than BAP but introduced new biases. We aimed to understand how the choice of denominator population impacts estimates of population size and health system performance for Pacific people at a local level.

METHODS

We described how declining census response rates affected population data quality. We compared BAP and HSU data at district level. For the indicators 'access to primary care' and 'cervical cancer screening uptake' we replaced currently used BAP denominators with HSU and examined the impact for different ethnic groups in different geographic districts.

RESULTS

Overall Census 2018 response declined by 10%, but for Māori and Pacific people by 21% and 23%, respectively. This inequitably affected BAP accuracy. Census undercount was highest in the district with the largest Pacific populations, where HSU exceeded BAP most. Notably, 'access to primary care' for Pacific people in this district consistently exceeds 100%. Using BAP, both health indicators are currently estimated as highest for Pacific people compared to other ethnic groups, but when based on HSU, they dropped to lowest. Similar, but less pronounced trends occurred in other districts. Changes in trends over time for both indicators coincided mostly with adjustments in BAP, rather than changes in the numerators.

CONCLUSIONS

The current use of BAP denominators for health statistics does not enable reliable monitoring of key health indicators for Pacific people. HSU denominators are also unsuitable for monitoring health. Exploring the feasibility of a real-time population register is strongly recommended as a new, transparent, way of obtaining more reliable, timely population data to guide policymaking and underpin a more equitable health system under the health reforms. Meanwhile, reporting of ethnic specific outcomes need to include a clear assessment of the potential for bias due to inaccurate population estimates.

The quest to deliver high-dose rifampicin: can the inhaled approach help?

INTRODUCTION

Tuberculosis (TB) is a global health problem that poses a challenge to global treatment programs. Rifampicin is a potent and highly effective drug for TB treatment; however, higher oral doses than the standard dose (10 mg/kg/day) rifampicin may offer better efficacy in TB treatment.

AREAS COVERED

High oral dose rifampicin is not implemented in anti-TB regimens yet and requires about a 3-fold increase in dose for increased efficacy. We discuss inhaled delivery of rifampicin as an alternative or adjunct to oral high-dose rifampicin. Clinical results of safety, tolerability, and patient compliance with antibiotic dry powder inhalers are reviewed.

EXPERT OPINION

Clinical trials suggest that an approximately 3-fold increase in the standard oral dose of rifampicin may be required for better clinical outcomes. On the other hand, animal studies suggest that inhaled rifampicin can deliver a high concentration of the drug to the lungs and achieve approximately double the plasma concentration than that from oral rifampicin. Clinical trials on inhaled antibiotics suggest that dry powder inhalation is a patient-friendly and well-tolerated approach in treating respiratory infections compared to conventional treatments. Rifampicin, a well-known anti-TB drug given orally, is a good candidate for clinical development as a dry powder inhaler.

Burden and associated phenotypic characteristics of tuberculosis infection in adult Africans with diabetes: a systematic review

Diabetes mellitus (DM) increases the risk of developing tuberculosis infection (TBI). However, the evidence on the burden and phenotypic characteristics of TBI in African patients with DM is limited. This study aimed to determine the prevalence and characterisation of TBI in native African patients living with DM. We searched PubMed, EMBASE, and African Journals Online for original studies reporting information on the prevalence and characteristics of TBI in adult Africans with DM. A forest plot was used to describe the pooled prevalence estimate of TBI and the corresponding 95% confidence intervals (CI). Six studies conducted in four African countries involving 721 participants with DM were included in this systematic review. The pooled prevalence estimate of TBI was 40% (95% CI 20-60%, I2 = 98.52%, p < 0.001). Age ≥ 40 years and glycated haemoglobin levels independently predicted TBI positivity in patients with DM in three studies. Africans with DM have a high prevalence of TBI, especially those who are older or with poorly controlled diabetes. This justifies the need for studies to explore how to screen and manage TBI to avert the progression to active TB disease.

An Aspiration to Radically Shorten Phase 3 Tuberculosis Vaccine Trials

A new tuberculosis vaccine is a high priority. However, the classical development pathway is a major deterrent. Most tuberculosis cases arise within 2 years after Mycobacterium tuberculosis exposure, suggesting a 3-year trial period should be possible if sample size is large to maximize the number of early exposures. Increased sample size could be facilitated by working alongside optimized routine services for case ascertainment, with strategies for enhanced case detection and safety monitoring. Shortening enrolment could be achieved by simplifying screening criteria and procedures and strengthening site capacity. Together, these measures could enable radically shortened phase 3 tuberculosis vaccine trials.

Molecular and clinical epidemiology of carbapenem resistant Acinetobacter baumannii ST2 in Oceania: a multicountry cohort study

Background

Carbapenem resistant Acinetobacter baumannii (CRAb) is categorised by the World Health Organization (WHO) as a pathogen of critical concern. However, little is known about CRAb transmission within the Oceania region. This study addresses this knowledge gap by using molecular epidemiology to characterise the phylogenetic relationships of CRAb isolated in hospitals in Fiji, Samoa, and other countries within the Oceania region including Australia and New Zealand, and India from South Asia.

Methods

In this multicountry cohort study, we analysed clinical isolates of CRAb collected from the Colonial War Memorial Hospital (CWMH) in Fiji from January through December 2019 (n = 64) and Tupua Tamasese Mea'ole Hospital (TTMH) in Samoa from November 2017 through June 2021 (n = 32). All isolates were characterised using mass spectrometry, antimicrobial susceptibility testing, and whole-genome sequencing. For CWMH, data were collected on clinical and demographic characteristics of patients with CRAb, duration of hospital stay, mortality and assessing the appropriateness of meropenem use from the treated patients who had CRAb infections. To provide a broader geographical context, CRAb strains from Fiji and Samoa were compared with CRAb sequences from Australia collected in 2016-2018 (n = 22), New Zealand in 2018-2021 (n = 13), and India in 2019 (n = 58), a country which has close medical links with Fiji. Phylogenetic relationships of all these CRAb isolates were determined using differences in core genome SNPs.

Findings

Of CRAb isolates, 49 (77%) of 64 from Fiji and all 32 (100%) from Samoa belonged to CRAb sequence type 2 (ST2). All ST2 isolates from both countries harboured blaOXA-23, blaOXA-66 and ampC-2 genes, mediating resistance to β-lactam antimicrobials, including cephalosporins and carbapenems. The blaOXA-23 gene was associated with two copies of ISAba1 insertion element, forming the composite transposon Tn2006, on the chromosome. Two distinct clusters (group 1 and group 2) of CRAb ST2 were detected in Fiji. The first group shared common ancestral linkage to all CRAb ST2 collected from Fiji's historic outbreak in 2016/2017, Samoa, Australia and 54% of total New Zealand isolates; they formed a single cluster with a median (range) SNP difference of 13 (0-102). The second group shared common ancestral linkage to 3% of the total CRAb ST2 isolated from India. Fifty eight of the 64 patients with CRAb infections at the CWMH had their first positive CRAb sample collected 72 h or more following admission. Meropenem use was deemed inappropriate in 15 (48%) of the 31 patients that received treatment with meropenem in Fiji. Other strains of CRAb ST1, ST25, ST107, and ST1112 were also detected in Fiji.

Interpretation

We identified unrecognised outbreaks of CRAb ST2 in Fiji and Samoa that linked to strains in other parts of Oceania and South Asia. The existence of Tn2006, containing the blaOXA-23 and ISAba1 insertion element, within CRAb ST2 from Fiji and Samoa indicates the potential for high mobility and dissemination. This raises concerns about unmitigated prolonged outbreaks of CRAb ST2 in the two major hospitals in Fiji and Samoa. Given the magnitude of this problem, there is a need to re-evaluate the current strategies used for infection prevention and control, antimicrobial stewardship, and public health measures locally and internationally. Moreover, a collaborative approach to AMR surveillance within the Oceania region with technical, management and budgetary support systems is required to prevent introduction and control transmission of these highly problematic strains within the island nation health systems.

Funding

This project was funded by an Otago Global Health Institute seed grant and Maurice Wilkins Centre of Research Excellence (CoREs) grant (SC0000169653, RO0000002300).

Invasive bacterial disease in young infants in rural Gambia: Population-based surveillance

Background

Invasive bacterial diseases (IBD) cause significant mortality in young infants. There are limited population-based data on IBD in young infants in Sub-Saharan Africa.

Methods

We conducted population-based surveillance for IBD among infants aged 0-90 days in a demographic surveillance area in rural Gambia between 1 March 2011 and 31 December 2017. Infants admitted to health facilities within the study area had standardised clinical evaluation plus conventional microbiological investigation. We defined IBD as isolation of pathogenic bacteria from blood, cerebrospinal fluid, lung, or pleural aspirate. We determined incidence, aetiology and case-fatality of IBD.

Results

A total of 3794 infants were admitted and 3605 (95%) had at least one sample collected for culture. We detected 254 (8.0%) episodes of IBD (bacteraemia 241; meningitis 14; pneumonia seven). The incidence of IBD in infants aged 0-90 days was 25 episodes/1000 person-years (95% confidence interval (CI) = 22-28), the incidence in neonates was 50 episodes/1000 person-years (95% CI = 43-58) and the incidence in infants aged 29-90 days was 12 episodes/1000 person-years (95% CI = 9-15). The most common pathogens causing IBD were Staphylococcus aureus (n = 102, 40%), Escherichia coli (n = 37, 15%), Streptococcus pneumoniae (n = 24, 9%) and Klebsiella pneumoniae (n = 12, 5%). Case-fatality was 29% (95% CI = 23-37) in neonates and 19% (95% CI = 11-29) in infants aged 29-90 days. A minimum of 7.3% of all young infant deaths in the population were caused by IBD.

Conclusions

IBD are common in young infants in rural Gambia and have a high case-fatality. Strategies are needed to prevent IBD in young infants. Overcoming barriers to widespread implementation of existing vaccines and developing new vaccines against the most common pathogens causing IBD should be among top priorities for reducing the high mortality rate in young infants.

Impaired resolution of blood transcriptomes through tuberculosis treatment with diabetes comorbidity

BACKGROUND

People with diabetes are more likely to develop tuberculosis (TB) and to have poor TB-treatment outcomes than those without. We previously showed that blood transcriptomes in people with TB-diabetes (TB-DM) co-morbidity have excessive inflammatory and reduced interferon responses at diagnosis. It is unknown whether this persists through treatment and contributes to the adverse outcomes.

METHODS

Pulmonary TB patients recruited in South Africa, Indonesia and Romania were classified as having TB-DM, TB with prediabetes, TB-related hyperglycaemia or TB-only, based on glycated haemoglobin concentration at TB diagnosis and after 6 months of TB treatment. Gene expression in blood at diagnosis and intervals throughout treatment was measured by unbiased RNA-Seq and targeted Multiplex Ligation-dependent Probe Amplification. Transcriptomic data were analysed by longitudinal mixed-model regression to identify whether genes were differentially expressed between clinical groups through time. Predictive models of TB-treatment response across groups were developed and cross-tested.

RESULTS

Gene expression differed between TB and TB-DM patients at diagnosis and was modulated by TB treatment in all clinical groups but to different extents, such that differences remained in TB-DM relative to TB-only throughout. Expression of some genes increased through TB treatment, whereas others decreased: some were persistently more highly expressed in TB-DM and others in TB-only patients. Genes involved in innate immune responses, anti-microbial immunity and inflammation were significantly upregulated in people with TB-DM throughout treatment. The overall pattern of change was similar across clinical groups irrespective of diabetes status, permitting models predictive of TB treatment to be developed.

CONCLUSIONS

Exacerbated transcriptome changes in TB-DM take longer to resolve during TB treatment, meaning they remain different from those in uncomplicated TB after treatment completion. This may indicate a prolonged inflammatory response in TB-DM, requiring prolonged treatment or host-directed therapy for complete cure. Development of transcriptome-based biomarker signatures of TB-treatment response should include people with diabetes for use across populations.

Evaluation of Ebola virus disease surveillance system capability to promptly detect a new outbreak in Liberia

INTRODUCTION

Liberia was heavily affected by the 2014-2016 Ebola virus disease (EVD) outbreak. With substantial investments in interventions to combat future outbreaks, it is hoped that Liberia is well prepared for a new incursion. We assessed the performance of the current EVD surveillance system in Liberia, focusing on its ability to promptly detect a new EVD outbreak.

METHODS

We integrated WHO and US Centers for Disease Control and Prevention guidelines for public health surveillance system evaluation and used standardised indicators to measure system performance. We conducted 23 key informant interviews, 150 health facility assessment surveys and a standardised patient (SP) study (19 visits) from January 2020 to January 2021. Data were summarised and a gap analysis conducted.

RESULTS

We found basic competencies of case detection and reporting necessary for a functional surveillance system were in place. At the higher (national, county and district) levels, we found performance gaps in 2 of 6 indicators relating to surveillance system structure, 3 of 14 indicators related to core functions, 1 of 5 quality indicators and 2 of 8 indicators related to support functions. The health facility assessment found performance gaps in 9 of 10 indicators related to core functions, 5 of 6 indicators related to support functions and 3 of 7 indicators related to quality. The SP simulations revealed large gaps between expected and actual practice in managing a patient warranting investigation for EVD. Major challenges affecting the system's operations across all levels included limited access to resources to support surveillance activities, persistent stock out of sample collection materials and attrition of trained staff.

CONCLUSION

The EVD surveillance system in Liberia may fail to promptly detect a new EVD outbreak. Specific improvements are required, and regular evaluations recommended. SP studies could be crucial in evaluating surveillance systems for rarely occurring diseases that are important to detect early.

Measuring indirect transmission-reducing effects in tuberculosis vaccine efficacy trials: why and how?

Tuberculosis is the leading bacterial cause of death globally. In 2021, 10·6 million people developed symptomatic tuberculosis and 1·6 million died. Seven promising vaccine candidates that aim to prevent tuberculosis disease in adolescents and adults are currently in late-stage clinical trials. Conventional phase 3 trials provide information on the direct protection conferred against infection or disease in vaccinated individuals, but they tell us little about possible indirect (ie, transmission-reducing) effects that afford protection to unvaccinated individuals. As a result, proposed phase 3 trial designs will not provide key information about the overall effect of introducing a vaccine programme. Information on the potential for indirect effects can be crucial for policy makers deciding whether and how to introduce tuberculosis vaccines into immunisation programmes. We describe the rationale for measuring indirect effects, in addition to direct effects, of tuberculosis vaccine candidates in pivotal trials and lay out several options for incorporating their measurement into phase 3 trial designs.

Clinical trials of tuberculosis vaccines in the era of increased access to preventive antibiotic treatment

Approximately 10·6 million people worldwide develop tuberculosis each year, representing a failure in epidemic control that is accentuated by the absence of effective vaccines to prevent infection or disease in adolescents and adults. Without effective vaccines, tuberculosis prevention has relied on testing for Mycobacterium tuberculosis infection and treating with antibiotics to prevent progression to tuberculosis disease, known as tuberculosis preventive treatment (TPT). Novel tuberculosis vaccines are in development and phase 3 efficacy trials are imminent. The development of effective, shorter, and safer TPT regimens has broadened the groups eligible for TPT beyond people with HIV and child contacts of people with tuberculosis; future vaccine trials will be undertaken in an era of increased TPT access. Changes in the prevention standard will have implications for tuberculosis vaccine trials of disease prevention, for which safety and sufficient accrual of cases are crucial. In this paper, we examine the urgent need for trials that allow the evaluation of new vaccines and fulfil the ethical duty of researchers to provide TPT. We observe how HIV vaccine trials have incorporated preventive treatment in the form of pre-exposure prophylaxis, propose trial designs that integrate TPT, and summarise considerations for each design in terms of trial validity, efficiency, participant safety, and ethics.

The August 2020 COVID-19 outbreak in Aotearoa, New Zealand: Delayed contact tracing for Pacific people contributes to widening health disparities

Background

After COVID-19 arrived in New Zealand, a national system was developed to improve the efficiency of contact tracing. The first outbreak was followed by a period of 'COVID-19 elimination', until a community outbreak occurred in August 2020. We describe the characteristics of cases and their contacts during this outbreak, focused on the results of contact tracing.

Methods

COVID-19 case data from the national surveillance database were linked to contacts from the national contact tracing database. Demographic and clinical characteristics of cases, number of contacts, and timeliness of contact tracing were analysed by ethnicity.

Findings

Most of the 179 cases were Pacific people (59%) or Māori (25%), living in areas of high socioeconomic deprivation, who had higher rates of comorbidity and accounted for almost all (21/22) hospitalisations, all 8 ICU admissions and all 3 deaths. Only 6% belonged to the European majority ethnic group. Of 2,528 registered contacts, 46% were Pacific, 14% Māori and 19% European. Only contacts that were reached were registered. Overall, 41% of contacts were reached within 4 days of onset of disease of the case, which was significantly lower for Pacific (31%) than for other ethnic groups.

Interpretation

Our findings confirm the greater health burden that ethnic minorities face from COVID-19. The significant delay in the timeliness of care for Pacific people shows that the public health response was inequitable for those at highest risk. Tailored public health responses and better registration of marginalised groups are necessary to provide better access to services and to improve insights for optimal future outbreak management.

Pneumonia, Meningitis, and Septicemia in Adults and Older Children in Rural Gambia: 8 Years of Population-Based Surveillance

BACKGROUND

Representative data describing serious infections in children aged ≥5 years and adults in Africa are limited.

METHODS

We conducted population-based surveillance for pneumonia, meningitis, and septicemia in a demographic surveillance area in The Gambia between 12 May 2008 and 31 December 2015. We used standardized criteria to identify, diagnose, and investigate patients aged ≥5 years using conventional microbiology and radiology.

RESULTS

We enrolled 1638 of 1657 eligible patients and investigated 1618. Suspected pneumonia, septicemia, or meningitis was diagnosed in 1392, 135, and 111 patients, respectively. Bacterial pathogens from sterile sites were isolated from 105 (7.5%) patients with suspected pneumonia, 11 (8.1%) with suspected septicemia, and 28 (25.2%) with suspected meningitis. Streptococcus pneumoniae (n = 84), Neisseria meningitidis (n = 16), and Staphylococcus aureus (n = 15) were the most common pathogens. Twenty-eight (1.7%) patients died in hospital and 40 (4.1%) died during the 4 months after discharge. Thirty postdischarge deaths occurred in patients aged ≥10 years with suspected pneumonia. The minimum annual incidence was 133 cases per 100 000 person-years for suspected pneumonia, 13 for meningitis, 11 for septicemia, 14 for culture-positive disease, and 46 for radiological pneumonia. At least 2.7% of all deaths in the surveillance area were due to suspected pneumonia, meningitis, or septicemia.

CONCLUSIONS

Pneumonia, meningitis, and septicemia in children aged ≥5 years and adults in The Gambia are responsible for significant morbidity and mortality. Many deaths occur after hospital discharge and most cases are culture negative. Improvements in prevention, diagnosis, inpatient, and follow-up management are urgently needed.

Diabetes characteristics and long-term management needs in diabetic TB patients

BACKGROUND: Diabetes mellitus (DM) is common among patients with TB. We assessed DM characteristics and long-term needs of DM-TB patients after completing TB treatment.METHODS: Newly diagnosed TB patients with DM were recruited for screening in a randomised clinical trial evaluating a simple algorithm to improve glycaemic control during TB treatment. DM characteristics, lifestyle and medication were compared before and after TB treatment and 6 months later. Risk of cardiovascular disease (CVD), albuminuria and neuropathy were assessed after TB treatment.RESULTS: Of 218 TB-DM patients identified, 170 (78%) were followed up. Half were males, the mean age was 53 years, 26.5% were newly diagnosed DM. High glycated haemoglobin at TB diagnosis (median 11.2%) decreased during TB treatment (to 7.4% with intensified management and 8.4% with standard care), but this effect was lost 6 months later (9.3%). Hypertension and dyslipidemia contributed to a high 10-year CVD risk (32.9% at month 6 and 35.5% at month 12). Neuropathy (33.8%) and albuminuria (61.3%) were common. After TB treatment, few patients used CVD-mitigating drugs.CONCLUSION: DM in TB-DM patients is characterised by poor glycaemic control, high CVD risk, and nephropathy. TB treatment provides opportunities for better DM management, but effort is needed to improve long-term care.

Rapid SARS-CoV-2 Seroprevalence Survey in Central and Western Divisions of Fiji, 2021

During November-December 2021, we performed a SARS-CoV-2 seroprevalence survey in Central and Western Divisions of Fiji. A total of 539 participants 8-70 years of age were 95.5% (95% CI 93.4%-97.1%) seropositive, indicating high community levels of immunity. Seroprevalence studies can inform public health responses to emerging SARS-CoV-2 variants.

Human papillomavirus genotype distribution among women with and without cervical cancer: Implication for vaccination and screening in Ghana

INTRODUCTION

Determining the high-risk human papillomavirus (HR-HPV) genotypes burden in women with and without cervical cancer afford a direct comparison of their relative distributions. This quest is fundamental to implementing a future population-based cervical cancer prevention strategy in Ghana. We estimated the cervical cancer risk by HPV genotypes, and the HPV vaccine-preventable proportion of cervical cancer diagnosed in Ghana.

MATERIALS AND METHODS

An unmatched case-control study was conducted at the two largest cervical cancer treatment centres in Ghana from 1st October 2014 to 31st May 2015. Cases were women diagnosed with cervical cancer and controls were women without cervical cancer who were seeking care at the two hospitals. Nested multiplex polymerase chain reaction (NM-PCR) was used to detect HPV infection in cervical samples. Logistic regression was used to determine the association between the risk of cervical cancer and identified HPV infection. P ≤0.05 was considered statistically significant.

RESULTS

HPV deoxyribonucleic acid (DNA) data were analysed for 177 women with cervical cancer (cases) and 201 without cancer (controls). Cervical cancer was diagnosed at older ages compared to the age at which controls were recruited (median ages, 57 years vs 34 years; p < 0.001). Most women with cervical cancer were more likely to be single with no formal education, unemployed and less likely to live in metropolitan areas compared to women without cervical cancer (all p-value <0.001). HPV DNA was detected in more women with cervical cancer compared to those without cervical cancer (84.8% vs 45.8%). HR-HPV genotypes 16, 18, 45, 35 and 52 were the most common among women with cervical cancer, while 66, 52, 35, 43 and 31 were frequently detected in those without cancer. HPV 66 and 35 were the most dominant non-vaccine genotypes; HPV 66 was more prevalent among women with cervical cancer and HPV 35 in those without cervical cancer. Cervical cancer risk was associated with a positive HPV test (Adjusted OR (AOR): 5.78; 95% CI: 2.92-11.42), infection with any of the HR-HPV genotypes (AOR: 5.56; 95% CI: 3.27-13.16) or multiple HPV infections (AOR: 9.57 95% CI 4.06-22.56).

CONCLUSION

Women with cervical cancer in Ghana have HPV infection with multiple genotypes, including some non-vaccine genotypes, with an estimated cervical cancer risk of about six- to ten-fold in the presence of a positive HPV test. HPV DNA tests and multivalent vaccine targeted at HPV 16, 18, 45 and 35 genotypes will be essential in Ghana's cervical cancer control programme. Large population-based studies are required in countries where cervical cancer is most prevalent to determine non-vaccine HPV genotypes which should be considered for the next-generation HPV vaccines.

A review of formulations and preclinical studies of inhaled rifampicin for its clinical translation

Inhaled drug delivery is a promising approach to achieving high lung drug concentrations to facilitate efficient treatment of tuberculosis (TB) and to reduce the overall duration of treatment. Rifampicin is a good candidate for delivery via the pulmonary route. There have been no clinical studies yet at relevant inhaled doses despite the numerous studies investigating its formulation and preclinical properties for pulmonary delivery. This review discusses the clinical implications of pulmonary drug delivery in TB treatment, the drug delivery systems reported for pulmonary delivery of rifampicin, animal models, and the animal studies on inhaled rifampicin formulations, and the research gaps hindering the transition from preclinical development to clinical investigation. A review of reports in the literature suggested there have been minimal attempts to test inhaled formulations of rifampicin in laboratory animals at relevant high doses and there is a lack of appropriate studies in animal models. Published studies have reported testing only low doses (≤ 20 mg/kg) of rifampicin, and none of the studies has investigated the safety of inhaled rifampicin after repeated administration. Preclinical evaluations of inhaled anti-TB drugs, such as rifampicin, should include high-dose formulations in preclinical models, determined based on allometric conversions, for relevant high-dose anti-TB therapy in humans.

Infant BCG vaccination and risk of pulmonary and extrapulmonary tuberculosis throughout the life course: a systematic review and individual participant data meta-analysis

BACKGROUND

BCG vaccines are given to more than 100 million children every year, but there is considerable debate regarding the effectiveness of BCG vaccination in preventing tuberculosis and death, particularly among older children and adults. We therefore aimed to investigate the age-specific impact of infant BCG vaccination on tuberculosis (pulmonary and extrapulmonary) development and mortality.

METHODS

In this systematic review and individual participant data meta-analysis, we searched MEDLINE, Web of Science, BIOSIS, and Embase without language restrictions for case-contact cohort studies of tuberculosis contacts published between Jan 1, 1998, and April 7, 2018. Search terms included "mycobacterium tuberculosis", "TB", "tuberculosis", and "contact". We excluded cohort studies that did not provide information on BCG vaccination or were done in countries that did not recommend BCG vaccination at birth. Individual-level participant data for a prespecified list of variables, including the characteristics of the exposed participant (contact), the index case, and the environment, were requested from authors of all eligible studies. Our primary outcome was a composite of prevalent (diagnosed at or within 90 days of baseline) and incident (diagnosed more than 90 days after baseline) tuberculosis in contacts exposed to tuberculosis. Secondary outcomes were pulmonary tuberculosis, extrapulmonary tuberculosis, and mortality. We derived adjusted odds ratios (aORs) using mixed-effects, binary, multivariable logistic regression analyses with study-level random effects, adjusting for the variable of interest, baseline age, sex, previous tuberculosis, and whether data were collected prospectively or retrospectively. We stratified our results by contact age and Mycobacterium tuberculosis infection status. This study is registered with PROSPERO, CRD42020180512.

FINDINGS

We identified 14 927 original records from our database searches. We included participant-level data from 26 cohort studies done in 17 countries in our meta-analysis. Among 68 552 participants, 1782 (2·6%) developed tuberculosis (1309 [2·6%] of 49 686 BCG-vaccinated participants vs 473 [2·5%] of 18 866 unvaccinated participants). The overall effectiveness of BCG vaccination against all tuberculosis was 18% (aOR 0·82, 95% CI 0·74-0·91). When stratified by age, BCG vaccination only significantly protected against all tuberculosis in children younger than 5 years (aOR 0·63, 95% CI 0·49-0·81). Among contacts with a positive tuberculin skin test or IFNγ release assay, BCG vaccination significantly protected against tuberculosis among all participants (aOR 0·81, 95% CI 0·69-0·96), participants younger than 5 years (0·68, 0·47-0·97), and participants aged 5-9 years (0·62, 0·38-0·99). There was no protective effect among those with negative tests, unless they were younger than 5 years (0·54, 0·32-0·90). 14 cohorts reported on whether tuberculosis was pulmonary or extrapulmonary (n=57 421). BCG vaccination significantly protected against pulmonary tuberculosis among all participants (916 [2·2%] in 41 119 vaccinated participants vs 334 [2·1%] in 16 161 unvaccinated participants; aOR 0·81, 0·70-0·94) but not against extrapulmonary tuberculosis (106 [0·3%] in 40 318 vaccinated participants vs 38 [0·2%] in 15 865 unvaccinated participants; 0·96, 0·65-1·41). In the four studies with mortality data, BCG vaccination was significantly protective against death (0·25, 0·13-0·49).

INTERPRETATION

Our results suggest that BCG vaccination at birth is effective at preventing tuberculosis in young children but is ineffective in adolescents and adults. Immunoprotection therefore needs to be boosted in older populations.

FUNDING

National Institutes of Health.

Childhood meningitis in rural Gambia: 10 years of population-based surveillance

Background

The introduction in many countries of conjugate vaccines against Haemophilus influenzae type b, Streptococcus pneumoniae, and Neisseria meningitidis has led to significant reductions in acute bacterial meningitis (ABM) in children. However, recent population-based data on ABM in sub-Saharan Africa are limited.

Methods

Population-based surveillance for meningitis was carried out in a rural area of The Gambia under demographic surveillance from 2008 to 2017, using standardised criteria for referral, diagnosis and investigation. We calculated incidence using population denominators.

Results

We diagnosed 1,666 patients with suspected meningitis and collected cerebrospinal fluid (n = 1,121) and/or blood (n = 1,070) from 1,427 (88%) of cases. We identified 169 cases of ABM, 209 cases of suspected non-bacterial meningitis (SNBM) and 1,049 cases of clinically suspected meningitis (CSM). The estimated average annual incidence of ABM was high at 145 per 100,000 population in the <2-month age group, 56 per 100,000 in the 2–23-month age group, but lower at 5 per 100,000 in the 5–14-year age group. The most common causes of ABM were Streptococcus pneumoniae (n = 44), Neisseria meningitidis (n = 42), and Gram-negative coliform bacteria (n = 26). Eighteen of 22 cases caused by pneumococcal serotypes included in PCV13 occurred prior to vaccine introduction and four afterwards. The overall case fatality ratio for ABM was 29% (49/169) and was highest in the <2-month age group 37% (10/27). The case fatality ratio was 8.6% (18/209) for suspected non-bacterial meningitis and 12.8% (134/1049) for clinically suspected meningitis cases.

Conclusions

Gambian children continue to experience substantial morbidity and mortality associated with suspected meningitis, especially acute bacterial meningitis. Such severely ill children in sub-Saharan Africa require improved diagnostics and clinical care.

Transcriptional profiles predict treatment outcome in patients with tuberculosis and diabetes at diagnosis and at two weeks after initiation of anti-tuberculosis treatment

BACKGROUND

Globally, the tuberculosis (TB) treatment success rate is approximately 85%, with treatment failure, relapse and death occurring in a significant proportion of pulmonary TB patients. Treatment success is lower among people with diabetes mellitus (DM). Predicting treatment outcome early after diagnosis, especially in TB-DM patients, would allow early treatment adaptation for individuals and may improve global TB control.

METHODS

Samples were collected in a longitudinal cohort study of adult TB patients from South Africa (n  =  94) and Indonesia (n  =  81), who had concomitant DM (n  =  59), intermediate hyperglycaemia (n  =  79) or normal glycaemia/no DM (n  =  37). Treatment outcome was monitored, and patients were categorized as having a good (cured) or poor (failed, recurrence, died) outcome during treatment and 12 months follow-up. Whole blood transcriptional profiles before, during and at the end of TB treatment were characterized using unbiased RNA-Seq and targeted gene dcRT-MLPA.

FINDINGS

We report differences in whole blood transcriptome profiles, which were observed before initiation of treatment and throughout treatment, between patients with a good versus poor TB treatment outcome. An eight-gene and a 22-gene blood transcriptional signature distinguished patients with a good TB treatment outcome from patients with a poor TB treatment outcome at diagnosis (AUC = 0·815) or two weeks (AUC = 0·834) after initiation of TB treatment, respectively. High accuracy was obtained by cross-validating this signature in an external cohort (AUC = 0·749).

INTERPRETATION

These findings suggest that transcriptional profiles can be used as a prognostic biomarker for treatment failure and success, even in patients with concomitant DM.

FUNDING

The research leading to these results, as part of the TANDEM Consortium, received funding from the European Community's Seventh Framework Programme (FP7/2007-2013 Grant Agreement No. 305279) and the Netherlands Organization for Scientific Research (NWO-TOP Grant Agreement No. 91214038). The research leading to the results presented in the Indian validation cohort was supported by Research Council of Norway Global Health and Vaccination Research (GLOBVAC) projects: RCN 179342, 192534, and 248042, the University of Bergen (Norway).

Mycobacterium tuberculosis infection and disease in healthcare workers in a tertiary referral hospital in Bandung, Indonesia

Background

Healthcare workers (HCWs), especially in high tuberculosis (TB) incidence countries, are at risk of Mycobacterium tuberculosis infection and TB disease, likely due to greater exposure to TB cases and variable implementation of infection control measures.

Aim

We aimed to estimate the prevalence of tuberculin skin test (TST) positivity, history of TB and to identify associated risk factors in HCWs employed at a tertiary referral hospital in Bandung, Indonesia.

Methods

A cross-sectional study was conducted from April to August 2018. A stratified sample of the HCWs were recruited, screened by TST, assessed for TB symptoms, history of TB disease and possible risk factors. Prevalence of positive TST included diagnosis with TB after starting work. HCWs with TB disease diagnosed earlier were excluded. Survey weights were used for all analyses. Possible risk factors were examined using logistic regression; adjusted odds ratios and 95% confidence intervals (CI) are presented.

Results

Of 455 HCWs recruited, 42 reported a history of TB disease (25 after starting work) and 395 had a TST result. The prevalence of positive TST was 76.9% (95% CI 72.6-80.8%). The odds increased by 7% per year at work (95% CI 3-11%) on average, with a rapid rise in TST positivity up to 10 years of work and then a plateau with around 80% positive.

Discussion

A high proportion of HCWs had a history of TB or were TST positive, increasing with longer duration of work. A package of TB infection control measures is needed to protect HCWs from Mycobacterium tuberculosis infection.

End-point definition and trial design to advance tuberculosis vaccine development

Tuberculosis (TB) remains a leading infectious cause of death worldwide and the coronavirus disease 2019 pandemic has negatively impacted the global TB burden of disease indicators. If the targets of TB mortality and incidence reduction set by the international community are to be met, new more effective adult and adolescent TB vaccines are urgently needed. There are several new vaccine candidates at different stages of clinical development. Given the limited funding for vaccine development, it is crucial that trial designs are as efficient as possible. Prevention of infection (POI) approaches offer an attractive opportunity to accelerate new candidate vaccines to advance into large and expensive prevention of disease (POD) efficacy trials. However, POI approaches are limited by imperfect current tools to measure Mycobacterium tuberculosis infection end-points. POD trials need to carefully consider the type and number of microbiological tests that define TB disease and, if efficacy against subclinical (asymptomatic) TB disease is to be tested, POD trials need to explore how best to define and measure this form of TB. Prevention of recurrence trials are an alternative approach to generate proof of concept for efficacy, but optimal timing of vaccination relative to treatment must still be explored. Novel and efficient approaches to efficacy trial design, in addition to an increasing number of candidates entering phase 2-3 trials, would accelerate the long-standing quest for a new TB vaccine.

Feasibility study of the prevalence of latent tuberculosis infection for Māori in the Waikato region, Aotearoa New Zealand

OBJECTIVE

This study aimed to assess the feasibility of conducting a representative tuberculin skin test (TST) survey for Māori in Aotearoa New Zealand and to estimate the prevalence of latent tuberculosis (TB) infection.

METHODS

Participants were Māori in the Waikato region, recruited by a Māori nurse, through: 1) random household selection from the Electoral Roll; 2) randomly selected prison inmates; and 3) community and health settings. A TB history and symptoms questionnaire was completed, TST performed and investigation of those with TST induration ≥10mm.

RESULTS

Random household selection was resource intensive and only contributed 14 participants. Repeated random selection of prison lists were required to recruit 207 participants and there were no positive TST cases. Community and health settings yielded the highest participation (n=370) and the three people (0.5%) with TST ≥10mm. Age ≥45 years and history of contact with a TB case were associated with TST induration ≥5mm (n=39; 6.6%).

CONCLUSIONS

The community and health settings were the only feasible options for recruitment. The overall prevalence of a positive TST in the study population was low. A 5mm cut-off may be best to maximise sensitivity for future studies.

IMPLICATIONS FOR PUBLIC HEALTH

A mixture of sample selection processes that are more targeted are needed to identify Māori with latent TB infection.

Rifapentine and isoniazid for prevention of tuberculosis in people with diabetes (PROTID): protocol for a randomised controlled trial

Background

Diabetes mellitus (DM) increases the risk of tuberculosis (TB) and will hamper global TB control due to the dramatic rise in type 2 DM in TB-endemic settings. In this trial, we will examine the efficacy and safety of TB preventive therapy against the development of TB disease in people with DM who have latent TB infection (LTBI), with a 12-week course of rifapentine and isoniazid (3HP).

Methods

The ‘Prevention of tuberculosis in diabetes mellitus’ (PROTID) consortium will randomise 3000 HIV-negative eligible adults with DM and LTBI, as evidenced by a positive tuberculin skin test or interferon gamma release assay, to 12 weeks of 3HP or placebo. Participants will be recruited through screening adult patients attending DM clinics at referral hospitals in Tanzania and Uganda. Patients with previous TB disease or treatment with a rifamycin medication or isoniazid (INH) in the previous 2 years will be excluded. The primary outcome is the occurrence of definite or probable TB disease; secondary outcome measures include adverse events, all-cause mortality and treatment completion. The primary efficacy analysis will be intention-to-treat; per-protocol analyses will also be carried out. We will estimate the ratio of TB incidence rates in intervention and control groups, adjusting for the study site using Poisson regression. Results will be reported as efficacy estimates (1-rate ratio). Cumulative incidence rates allowing for death as a competing risk will also be reported. Approximately 1000 LTBI-negative, HIV-negative participants will be enrolled consecutively into a parallel cohort study to compare the incidence of TB in people with DM who are LTBI negative vs positive. A number of sub-studies will be conducted among others to examine the prevalence of LTBI and active TB, estimate the population impact and cost-effectiveness of LTBI treatment in people living with DM in these African countries and address gaps in the prevention and therapeutic management of combined TB-DM.

Discussion

PROTID is anticipated to generate key evidence to guide decisions over the use of TB preventive treatment among people with DM as an important target group for better global TB control.

Trial registration

ClinicalTrials.govNCT04600167. Registered on 23 October 2020

Tuberculosis among Patients with Systemic Lupus Erythematosus in Indonesia: a Cohort study

Background

Previous studies have identified systemic lupus erythematosus (SLE) as a risk factor for tuberculosis (TB), but data from TB endemic countries are still relatively scarce. We examined TB in a large cohort of SLE patients in Indonesia.

Methods

All patients registered in a lupus registry of the top-referral hospital for West-Java between 2008 and 2020 were included. Data on SLE characteristics and treatment were retrieved from the registry, and data on TB diagnosis, localization and outcome were extracted from medical records. Cox-proportional hazard model was used to examine risk factors for development of TB.

Results

Among 1278 SLE patients followed over a total of 4804 patient years, 131 patients experienced 138 episodes of TB, a median 2 years (IQR 0.6–5.4) after diagnosis of SLE. A total of 113 patients (81.9%) had pulmonary and 61 (44.2%) had extra-pulmonary involvement, with disseminated disease in 26 of 138 episodes (18.8%), and 13 of 131 patients (9.9%) died from TB. The estimated TB incidence was 2,873 cases per 100,000 person years. In multivariate cox regression analysis, development of TB was associated with household TB contact (HR 7.20; 95%CI 4.05-12.80), pulse methylprednisolone therapy (HR 1.64; 95%CI 1.01-2.67) and age ≤ 25 years old at SLE diagnosis (HR 1.54; 95%CI 1.00-2.35).

Conclusion

There is a high burden of TB in SLE patients in this TB endemic setting, underlining the need for evaluation or implementation of TB preventive strategies.

Vaccine mandates in the time of Omicron

Nil.

A public health intervention package for increasing tuberculosis notifications from private practitioners in Bandung, Indonesia (INSTEP2): A cluster-randomised controlled trial protocol

Background. A significant proportion of tuberculosis (TB) patients globally make their initial visit for medical care to either an informal provider or a private practitioner, and many are not formally notified. Involvement of private practitioners (PPs) in a public–private mix for TB (TB-PPM) provides an opportunity for improving TB control. However, context-specific interventions beyond public–private agreements and mandatory notification are needed. In this study we will evaluate whether a tailored intervention package can increase TB notifications from PPs in Indonesia. Methods. This is a cluster-randomized trial of a multi-component public health intervention. 36 community health centre (CHC) areas will be selected as study locations and randomly allocated to intervention and control arms (1:1). PPs in the intervention areas will be identified using a mapping exercise and recruited into the study if they are eligible and consent. They will receive a tailored intervention package including in-person education about TB management along with bimonthly electronic refreshers, context-specific selection of referral pathways, and access to a TB-reporting app developed in collaboration with the National TB programme. The primary hypothesis is that the intervention package will increase the TB notification rate. The primary outcome will be measured by collecting notification data from the CHCs in intervention and control arms at the end of a 1-year observation period and comparing with the 1-year pre-intervention. The primary analysis will be intention-to-treat at the cluster level, using a generalised mixed model with repeated measures of TB notifications for 1 year pre- and 1 year post-intervention. Discussion. The results from this study will provide evidence on whether a tailored intervention package is effective in increasing the number of TB notifications, and whether the PPs refer presumptive TB cases correctly. The study results will guide policy in the development of TB-PPM in Indonesia and similar settings.

Tuberculosis infection control measures and knowledge in primary health centres in Bandung, Indonesia

Background

Health care workers (HCWs) in low- and middle-income countries (LMICs) continue to have an unacceptably high prevalence and incidence of Mycobacterium tuberculosis infection due to high exposure to tuberculosis (TB) cases at health care facilities and often inadequate infection control measures. This can contribute to an increased risk of transmission not only to HCWs themselves but also to patients and the general population.

Aim

We assessed implementation of TB infection control measures in primary health centres (PHCs) in Bandung, Indonesia, and TB knowledge among HCWs.

Methods

A cross-sectional study was conducted between May and November 2017 amongst a stratified sample of the PHCs, and their HCWs, that manage TB patients in Bandung. Questionnaires were used to assess TB infection control measures plus HCW knowledge. Summary statistics, linear regression and the Kruskal-Wallis test were used for analysis.

Results

The median number of TB infection control measures implemented in 24 PHCs was 21 of 41 assessed. Only one of five management controls was implemented, 15 of 24 administrative controls, three of nine environmental controls and one of three personal respiratory protection controls. PHCs with TB laboratory facilities and high TB case numbers were more likely to implement TB infection control measures than other PHCs (p=0.003). In 398 HCWs, the median number of correct responses for knowledge was 10 (IQR 9-11) out of 11.

Discussion

HCWs had good TB knowledge. TB infection control measures were generally not implemented and need to be strengthened in PHCs to reduce M. tuberculosis transmission to HCWs, patients and visitors.

Implementing the 4R and 9H regimens for TB preventive treatment in Indonesia

BACK GROUND:

The implementation of tuberculosis preventive treatment (TPT) is challenging especially in resource-limited settings. As part of a Phase 3 trial on TPT, we described our experience with the use of rifampicin for 4 months (4R) and isoniazid for 9 months (9H) in Indonesia.

METHODS:

In 2011–2017, children and adults with latent TB infection were randomised to either 4R or 9H and followed until 16 months after randomisation for children and 28 months for adults. The primary outcome was the treatment completion rate. Secondary outcomes were Grade 3–5 adverse events (AEs), active TB occurrence, and health costs.

RESULTS:

A total of 157 children and 860 adults were enrolled. The 4R treatment completion rate was significantly higher than that of 9H (78.7% vs. 65.5%), for a rate difference of 13.2% (95% CI 7.1–19.2). No Grade 3–5 AEs were reported in children; in adults, it was lower in 4R (0.4%) compared to 9H (2.8%). The incidence of active TB was lower with 4R than with 9H (0.09/100 person-year vs. 0.36/100 person-year) (rate difference: −0.36/100 person-year). The total cost per patient was lower for the 4R regimen than for the 9H regimen (USD151.9 vs. USD179.4 in adults and USD152.9 vs. USD206.5 in children)

CONCLUSIONS:

Completion and efficacy rates for 4R were better than for 9H. Compared to 9H, 4R was cheaper in all age groups, safer in adults and equally safe in children. The Indonesian TB program could benefit from these benefits of the 4R regimen.

Protection against tuberculosis by Bacillus Calmette-Guérin (BCG) vaccination: A historical perspective

Bacillus Calmette-Guérin (BCG) was developed exactly 100 years ago, and it is still the only licensed tuberculosis (TB) vaccine and the most frequently administered of all vaccines worldwide. Despite universal vaccination policies in TB-endemic settings, the burden of TB remains high. Although BCG protects against Mycobacterium tuberculosis infection and TB disease, the level of protection varies greatly between age groups and settings. In this review, we present a historical perspective and describe the evidence for BCG's ability to protect against TB as well as the factors that influence protection. We also present the immunological mechanisms through which BCG vaccination induces protection, focusing on T cell, B cell, and innate immunity. Finally, we discuss several possibilities to boost BCG's efficacy, including alternative vaccination routes, BCG revaccination, and use of recombinant BCG vaccines, and describe the knowledge gaps that exist with respect to BCG's protection against TB.

Educational counselling of patients with combined TB and diabetes mellitus: a randomised trial

SETTING

Newly diagnosed pulmonary TB with diabetes mellitus (DM) comorbidity attending clinics in Bandung City, Indonesia.

OBJECTIVE

To describe the effect of educational counselling on patients' knowledge about TB (transmission, treatment, risk factors) and DM (symptoms, treatment, complications, healthy lifestyle), adherence to medication, and to assess characteristics associated with knowledge.

DESIGN

All patients received counselling and were then randomised to either structured education on TB-DM, combined with clinical monitoring and medication adjustment (intervention arm), or routine care (control arm). Knowledge and adherence were assessed using a questionnaire.

RESULTS

Baseline and 6-month questionnaires were available for 108 of 150 patients randomised (60/76 in the intervention arm and 48/74 in the control arm). Patients knew less about DM than about TB. There was no significant difference in the proportion with knowledge improvement at 6 months, both for TB (difference of differences 14%; P = 0.20) or for DM (10%; P = 0.39) between arms. Intervention arm patients were more likely to adhere to taking DM medication, with fewer patients reporting ever missing oral DM drugs than those in the control arm (23% vs. 48%; P = 0.03). Higher education level was associated with good knowledge of both TB and DM.

CONCLUSIONS

Structured education did not clearly improve patients' knowledge. It was associated with better adherence to DM medication, but this could not be attributed to education alone. More efforts are needed to improve patients' knowledge, especially regarding DM.

Genomic Profiling of Mycobacterium tuberculosis Strains, Myanmar

Multidrug resistance is a major threat to global elimination of tuberculosis (TB). We performed phenotypic drug-susceptibility testing and whole-genome sequencing for 309 isolates from 342 consecutive patients who were given a diagnosis of TB in Yangon, Myanmar, during July 2016‒June 2018. We identified isolates by using the GeneXpert platform to evaluate drug-resistance profiles. A total of 191 (62%) of 309 isolates had rifampin resistance; 168 (88%) of these rifampin-resistant isolates were not genomically related, indicating the repeated emergence of resistance in the population, rather than extensive local transmission. We did not detect resistance mutations to new oral drugs, including bedaquiline and pretomanid. The current GeneXpert MTB/RIF system needs to be modified by using the newly launched Xpert MTB/XDR cartridge or line-probe assay. Introducing new oral drugs to replace those currently used in treatment regimens for multidrug-resistant TB will also be useful for treating TB in Myanmar.

Impact of the introduction of pneumococcal conjugate vaccination on invasive pneumococcal disease and pneumonia in The Gambia: 10 years of population-based surveillance

Background

The Gambia introduced seven-valent pneumococcal conjugate vaccine (PCV7) in August 2009, followed by PCV13 in May, 2011, using a schedule of three primary doses without a booster dose or catch-up immunisation. We aimed to assess the long-term impact of PCV on disease incidence.

Methods

We did 10 years of population-based surveillance for invasive pneumococcal disease (IPD) and WHO defined radiological pneumonia with consolidation in rural Gambia. The surveillance population included all Basse Health and Demographic Surveillance System residents aged 2 months or older. Nurses screened all outpatients and inpatients at all health facilities using standardised criteria for referral. Clinicians then applied criteria for patient investigation. We defined IPD as a compatible illness with isolation of Streptococcus pneumoniae from a normally sterile site (cerebrospinal fluid, blood, or pleural fluid). We compared disease incidence between baseline (May 12, 2008–May 11, 2010) and post-vaccine years (2016–2017), in children aged 2 months to 14 years, adjusting for changes in case ascertainment over time.

Findings

We identified 22 728 patients for investigation and detected 342 cases of IPD and 2623 cases of radiological pneumonia. Among children aged 2–59 months, IPD incidence declined from 184 cases per 100 000 person-years to 38 cases per 100 000 person-years, an 80% reduction (95% CI 69–87). Non-pneumococcal bacteraemia incidence did not change significantly over time (incidence rate ratio 0·88; 95% CI, 0·64–1·21). We detected zero cases of vaccine-type IPD in the 2–11 month age group in 2016–17. Incidence of radiological pneumonia decreased by 33% (95% CI 24–40), from 10·5 to 7·0 per 1000 person-years in the 2–59 month age group, while pneumonia hospitalisations declined by 27% (95% CI 22–31). In the 5–14 year age group, IPD incidence declined by 69% (95% CI −28 to 91) and radiological pneumonia by 27% (95% CI −5 to 49).

Interpretation

Routine introduction of PCV13 substantially reduced the incidence of childhood IPD and pneumonia in rural Gambia, including elimination of vaccine-type IPD in infants. Other low-income countries can expect substantial impact from the introduction of PCV13 using a schedule of three primary doses.

Funding

Gavi, The Vaccine Alliance; Bill & Melinda Gates Foundation; UK Medical Research Council; Pfizer Ltd.

Cost analysis and critical success factors of the use of oxygen concentrators versus cylinders in sub-divisional hospitals in Fiji

Background

Oxygen is vital in the treatment of illnesses in children and adults, yet is lacking in many low and middle-income countries health care settings. Oxygen concentrators (OCs) can increase access to oxygen, compared to conventional oxygen cylinders. We investigated the costs and critical success factors of OCs in three hospitals in Fiji, and extrapolated these to estimate the oxygen delivery cost to all Sub-Divisional hospitals (SDH) nationwide.

Methods

Data sources included key personnel interviews, and data from SDH records, Ministry of Health and Medical Services, and a non-governmental organisation. We used Investment Logic Mapping (ILM) to define key issues. An economic case was developed to identify the investment option that optimised value while incorporating critical success factors identified through ILM. A fit-for-purpose analysis was conducted using cost analysis of four short-listed options. Sensitivity analyses were performed by altering variables to show the best or worst case scenario. All costs are presented in Fijian dollars.

Results

Critical success factors identifed included oxygen availability, safety, ease of use, feasibility, and affordability. Compared to the status quo of having only oxygen cylinders, an option of having a minimum number of concentrators with cylinder backup would cost $434,032 (range: $327,940 to $506,920) over 5 years which would be 55% (range: 41 to 64%) of the status quo cost.

Conclusion

Introducing OCs into all SDHs in Fiji would reduce overall costs, while ensuring identified critical success factors are maintained. This study provides evidence for the benefits of OCs in this and similar settings.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12913-021-06687-8.

Screening diabetes mellitus patients for pulmonary tuberculosis: a multisite study in Indonesia, Peru, Romania and South Africa

BACKGROUND

Diabetes mellitus (DM) patients are three times more likely to develop tuberculosis (TB) than the general population. Active TB screening in people with DM is part of a bidirectional approach. The aim of this study was to conduct pragmatic active TB screening among DM patients in four countries to inform policy.

METHODS

DM patients were recruited in Indonesia (n=809), Peru (n=600), Romania (n=603) and South Africa (n=51). TB cases were diagnosed using an algorithm including clinical symptoms and chest X-ray. Presumptive TB patients were examined with sputum smear and culture.

RESULTS

A total of 171 (8.3%) individuals reported ever having had TB (South Africa, 26%; Indonesia, 12%; Peru, 7%; Romania, 4%), 15 of whom were already on TB treatment. Overall, 14 (0.73% [95% confidence interval 0.40 to 1.23]) TB cases were identified from screening. Poor glucose control, smoking, lower body mass index, education and socio-economic status were associated with newly diagnosed/current TB. Thirteen of the 14 TB cases diagnosed from this screening would have been found using a symptom-based approach.

CONCLUSIONS

These data support the World Health Organization recommendation for routine symptom-based screening for TB in known DM patients in high TB-burden countries. DM patients with any symptoms consistent with TB should be investigated and diagnostic tools should be easily accessible.

High tuberculosis incidence among people living with diabetes in Indonesia

BACKGROUND

Data regarding the incidence of tuberculosis (TB) among people living with diabetes (PLWD) in TB-endemic settings are scarce. We examined TB incidence among PLWD in Indonesia who had previously been screened for latent TB infection (LTBI) and TB disease.

METHODS

PLWD (≥18 y of age) in an urban setting were examined a mean 3.4 y after they had been screened for active TB and LTBI. Data on subsequent TB diagnosis were collected by interview and with chest X-ray, sputum smear and Mycobacterium tuberculosis culture. TB incidence rates were stratified for baseline LTBI status, as determined by the QuantiFERON interferon-gamma release assay (IGRA).

RESULTS

Of 590 PLWD, 101 had died and 163 could not be contacted or refused. Among the 326 who were re-examined, 6 (1.8%; 95% confidence interval [CI] 0.7 to 4.0) reported being diagnosed already and a further 5 were diagnosed with active TB (1.5%; 95% CI 0.50 to 3.5). The TB incidence rate was 9.85 (95% CI 4.03 to 15.68) per 1000 person-years. TB incidence was higher among PLWD with baseline LTBI (17.13; 95% CI 5.25 to 29.00/1000 person-years) compared with those without LTBI (4.79; 95% CI -0.63 to 10.21), with an incidence rate ratio of 3.57 (95% CI 0.86 to 20.92; p=0.054).

CONCLUSIONS

PLWD with LTBI in Indonesia and similar settings are likely to benefit from TB preventive therapy.

BCG-induced protection against Mycobacterium tuberculosis infection: Evidence, mechanisms, and implications for next-generation vaccines

The tuberculosis (TB) vaccine Bacillus Calmette-Guérin (BCG) was introduced 100 years ago, but as it provides insufficient protection against TB disease, especially in adults, new vaccines are being developed and evaluated. The discovery that BCG protects humans from becoming infected with Mycobacterium tuberculosis (Mtb) and not just from progressing to TB disease provides justification for considering Mtb infection as an endpoint in vaccine trials. Such trials would require fewer participants than those with disease as an endpoint. In this review, we first define Mtb infection and disease phenotypes that can be used for mechanistic studies and/or endpoints for vaccine trials. Secondly, we review the evidence for BCG-induced protection against Mtb infection from observational and BCG re-vaccination studies, and discuss limitations and variation of this protection. Thirdly, we review possible underlying mechanisms for BCG efficacy against Mtb infection, including alternative T cell responses, antibody-mediated protection, and innate immune mechanisms, with a specific focus on BCG-induced trained immunity, which involves epigenetic and metabolic reprogramming of innate immune cells. Finally, we discuss the implications for further studies of BCG efficacy against Mtb infection, including for mechanistic research, and their relevance to the design and evaluation of new TB vaccines.

A public health approach to increase treatment of latent TB among household contacts in Brazil

SETTING: Two consecutive trials were conducted to evaluate the effectiveness of a public health approach to identify and correct problems in the care cascade for household contacts (HHCs) of TB patients in three Brazilian high TB incidence cities.METHODS: In the first trial, 12 clinics underwent standardised evaluation using questionnaires administered to TB patients, HHCs and healthcare workers, and analysis of the cascade of latent TB care among HHCs. Six clinics were then randomised to receive interventions to strengthen management of latent TB infection (LTBI), including in-service training provided by nurses, work process organisation and additional clinic-specific solutions. In the second trial, a similar but streamlined evaluation was conducted in two clinics, who then received initial and subsequent intensive in-service training provided by a physician.RESULTS: In the evaluation phase of both trials, many HHCs were identified, but few started LTBI treatment. After the intervention, the number of HHCs initiating treatment per 100 active TB patients increased by 10 (95%CI - 11 to 30) in the first trial, and by 44 (95%CI 26 to 61) in the second trial.DISCUSSION: A public health approach with standardised evaluation, local decisions for improvements, followed by intensive initial and in-service training appears promising for improved LTBI management.

A public health intervention package for increasing tuberculosis notifications from private practitioners in Bandung, Indonesia (INSTEP2): A cluster-randomised controlled trial protocol

Background. A significant proportion of tuberculosis (TB) patients globally make their initial visit for medical care to either an informal provider or a private practitioner, and many are not formally notified. Involvement of private practitioners (PPs) in a public-private mix for TB (TB-PPM) provides an opportunity for improving TB control. However, context-specific interventions beyond public-private agreements and mandatory notification are needed. In this study we will evaluate whether a tailored intervention package can increase TB notifications from PPs in Indonesia. Methods. This is a cluster-randomized trial of a multi-component public health intervention. 36 community health centre (CHC) areas will be selected as study locations and randomly allocated to intervention and control arms (1:1). PPs in the intervention areas will be identified using a mapping exercise and recruited into the study if they are eligible and consent. They will receive a tailored intervention package including in-person education about TB management along with bimonthly electronic refreshers, context-specific selection of referral pathways, and access to a TB-reporting app developed in collaboration with the National TB programme. The primary hypothesis is that the intervention package will increase the TB notification rate. The primary outcome will be measured by collecting notification data from the CHCs in intervention and control arms at the end of a 1-year observation period and comparing with the 1-year pre-intervention. The primary analysis will be intention-to-treat at the cluster level, using a generalised mixed model with repeated measures of TB notifications for 1 year pre- and 1 year post-intervention. Discussion. The results from this study will provide evidence on whether a tailored intervention package is effective in increasing the number of TB notifications, and whether the PPs refer presumptive TB cases correctly. The study results will guide policy in the development of TB-PPM in Indonesia and similar settings.

Effectiveness and cost-effectiveness of a health systems intervention for latent tuberculosis infection management (ACT4): a cluster-randomised trial

BACKGROUND

Reaching the UN General Assembly High-Level Meeting on Tuberculosis target of providing tuberculosis preventive treatment to at least 30 million people by 2022, including 4 million children under the age of 5 years and 20 million other household contacts, will require major efforts to strengthen health systems. The aim of this study was to evaluate the effectiveness and cost-effectiveness of a health systems intervention to strengthen management for latent tuberculosis infection (LTBI) in household contacts of confirmed tuberculosis cases.

METHODS

ACT4 was a cluster-randomised, open-label trial involving 24 health facilities in Benin, Canada, Ghana, Indonesia, and Vietnam randomly assigned to either a three-phase intervention (LTBI programme evaluation, local decision making, and strengthening activities) or control (standard LTBI care). Tuberculin and isoniazid were provided to control and intervention sites if not routinely available. Randomisation was stratified by country and restricted to ensure balance of index patients with tuberculosis by arm and country. The primary outcome was the number of household contacts who initiated tuberculosis preventive treatment at each health facility within 4 months of the diagnosis of the index case, recorded in the first or last 6 months of our 20-month study. To ease interpretation, this number was standardised per 100 newly diagnosed index patients with tuberculosis. Analysis was by intention to treat. Masking of staff at the coordinating centre and sites was not possible; however, those analysing data were masked to assignment of intervention or control. An economic analysis of the intervention was done in parallel with the trial. ACT4 is registered at ClinicalTrials.gov, NCT02810678.

FINDINGS

The study was done between Aug 1, 2016, and March 31, 2019. During the first 6 months of the study the crude overall proportion of household contacts initiating tuberculosis preventive treatment out of those eligible at intervention sites was 0·21. After the implementation of programme strengthening activities, the proportion initiating tuberculosis preventive treatment increased to 0·35. Overall, the number of household contacts initiating tuberculosis preventive treatment per 100 index patients with tuberculosis increased between study phases in intervention sites (adjusted rate difference 60, 95% CI 4 to 116), while control sites showed no statistically significant change (-12, -33 to 10). There was a difference in rate differences of 72 (95% CI 10 to 134) contacts per 100 index patients with tuberculosis initiating preventive treatment associated with the intervention. The total cost for the intervention, plus LTBI clinical care per additional contact initiating treatment was estimated to be CA$1348 (range 724 to 9708).

INTERPRETATION

A strategy of standardised evaluation, local decision making, and implementation of health systems strengthening activities can provide a mechanism for scale-up of tuberculosis prevention, particularly in low-income and middle-income countries.

FUNDING

Canadian Institutes of Health Research.

Studies on the safety and the tissue distribution of inhaled high-dose amorphous and crystalline rifampicin in a rat model

Inhaled delivery of rifampicin has the potential to achieve high drug concentrations in the lung and the blood for efficient treatment of tuberculosis (TB). Due to its existence as polymorphs, in vivo evaluation of the respiratory tract safety of inhalable amorphous and crystalline rifampicin particles, at clinically relevant high-dose, is necessary. This study investigates the lung and liver safety and the tissue distribution of rifampicin after intra-tracheal administration of high (≥25 mg/kg) doses of amorphous and crystalline powder formulations to Sprague Dawley rats. Powder formulations were administered by intra-tracheal insufflation to rats. Lung and liver safety were evaluated by histopathology. Serum alanine transaminase (ALT) and aspartate aminotransferase (AST) assays were performed to study the hepatic effects. Rifampicin was quantified in the tissues using LC-MS/MS. Intra-tracheal administration of rifampicin decreased the drug burden on the liver compared to oral administration based on its lower serum ALT activity. Repeated-dose intra-tracheal rifampicin was well tolerated by rats, confirmed by the absence of drug or delivery induced complexities. The histopathological evaluation of rat lungs, after both single and repeated drug administration for seven days, suggested the absence of drug-induced toxicity. Following single intra-tracheal delivery of 50 mg/kg doses, comparable rifampicin concentrations to that from same oral dose were observed in lung, liver, heart and brain. Inhaled delivery of high-dose rifampicin was safe to rat lungs and liver suggesting its potential for localized as well as systemic drug delivery without toxicity concerns.

High risk of Mycobacterium tuberculosis infection among medical and nursing students in Indonesia: a 1-year prospective study

BACKGROUND

Medical and nursing students entering their clinical programmes are at increased risk for tuberculosis (TB) in TB-endemic settings. Relatively little is known about Mycobacterium tuberculosis infection among such students in high-endemic countries.

METHODS

We examined M. tuberculosis infection among medical and nursing students starting clinical training in Bandung, Indonesia using interferon-γ release assay (IGRA) QuantiFERON-TB Gold Plus. IGRA-negative students had a repeat test after 1 y and logistic regression was used to identify factors associated with IGRA positivity or conversion.

RESULTS

There were 379 students included in this study: 248 (65.4%) were medical students and 131 (34.6%) were nursing students. Of 379 students, 70 (18.5%) were IGRA positive at baseline. Of 293 IGRA-negative students with 1-y results, 26 (8.9%) underwent IGRA conversion. Being a medical student (adjusted relative risk [ARR] 5.15 [95% confidence interval {CI} 1.82 to 14.59], p=0.002) and participation in sputum collection or bronchoscopy were associated with IGRA conversion (ARR 2.74 [95% CI 1.29 to 5.79], p=0.008).

CONCLUSIONS

Medical and nursing students entering clinical training are at high risk of M. tuberculosis infection and need improved infection prevention and control strategies.

Changes in Transcript, Metabolite, and Antibody Reactivity During the Early Protective Immune Response in Humans to Mycobacterium tuberculosis Infection

Background

Strategies to prevent Mycobacterium tuberculosis (Mtb) infection are urgently required. In this study, we aimed to identify correlates of protection against Mtb infection.

Methods

Two groups of Mtb-exposed contacts of tuberculosis (TB) patients were recruited and classified according to their Mtb infection status using the tuberculin skin test (TST; cohort 1) or QuantiFERON (QFT; cohort 2). A negative reading at baseline with a positive reading at follow-up classified TST or QFT converters and a negative reading at both time points classified TST or QFT nonconverters. Ribonucleic acid sequencing, Mtb proteome arrays, and metabolic profiling were performed.

Results

Several genes were found to be differentially expressed at baseline between converters and nonconverters. Gene set enrichment analysis revealed a distinct B-cell gene signature in TST nonconverters compared to converters. When infection status was defined by QFT, enrichment of type I interferon was observed. A remarkable area under the curve (AUC) of 1.0 was observed for IgA reactivity to Rv0134 and an AUC of 0.98 for IgA reactivity to both Rv0629c and Rv2188c. IgG reactivity to Rv3223c resulted in an AUC of 0.96 and was markedly higher compared to TST nonconverters. We also identified several differences in metabolite profiles, including changes in biomarkers of inflammation, fatty acid metabolism, and bile acids. Pantothenate (vitamin B5) was significantly increased in TST nonconverters compared to converters at baseline (q = 0.0060).

Conclusions

These data provide new insights into the early protective response to Mtb infection and possible avenues to interfere with Mtb infection, including vitamin B5 supplementation.

Analysis of blood from highly exposed household contacts from The Gambia who never develop latent Mycobacterium tuberculosis infection shows distinct transcriptomic, antibody, and metabolomic profiles compared to those who develop latent tuberculosis infection but prior to any signs of infection.