Healthcare seeking patterns for TB symptoms: Findings from the first national TB prevalence survey of South Africa, 2017-2019

BACKGROUND

Although tuberculosis (TB) symptoms have limited sensitivity they remain an important entry point into the TB care cascade.

OBJECTIVES

To investigate self-reported healthcare seeking for TB symptoms in participants in a community-based survey.

METHODS

We compared reasons for not seeking care in participants reporting ≥1 of four TB screening symptoms (cough, weight loss, night sweats, fever) in the first South African national TB prevalence survey (2017-2019). We used logistic regression analyses to identify sociodemographic and clinical characteristics associated with healthcare seeking.

RESULTS

5,168/35,191 (14.7%) survey participants reported TB symptoms and 3,442/5168 had not sought healthcare. 2,064/3,442(60.0%) participants intended to seek care, 912 (26.5%) regarded symptoms as benign, 399 (11.6%) reported access barriers(distance and cost), 36 (1.0%) took other medications and 20(0.6%) reported health system barriers. Of the 57/98 symptomatic participants diagnosed with bacteriologically confirmed TB who had not sought care: 38(66.7%) intended to do so, 8(14.0%) regarded symptoms as benign, and 6(10.5%) reported access barriers. Among these 98, those with unknown HIV status(OR 0.16 95% CI 0.03-0.82), p = 0.03 and those who smoked tobacco products(OR 0.39, 95% CI 0.17-0.89, p = 0.03) were significantly less likely to seek care.

CONCLUSIONS

People with TB symptoms delayed seeking healthcare, many regarded symptoms as benign while others faced access barriers. Those with unknown HIV status were significantly less likely to seek care. Strengthening community-based TB awareness and screening programmes together with self-screening models could increase awareness of the significance of TB symptoms and contribute to improving healthcare seeking and enable many people with TB to enter the TB care cascade.

The Impact of the Evolving Human Immunodeficiency Virus Response on the Epidemiology of Tuberculosis in South African Children and Adolescents

BACKGROUND

Few studies have evaluated tuberculosis control in children and adolescents. We used routine tuberculosis surveillance data to quantify age- and human immunodeficiency virus (HIV)-stratified trends over time and investigate the relationship between tuberculosis, HIV, age, and sex.

METHODS

All children and adolescents (0-19 years) routinely treated for drug-susceptible tuberculosis in South Africa and recorded in a de-duplicated national electronic tuberculosis treatment register (2004-2016) were included. Age- and HIV-stratified tuberculosis case notification rates (CNRs) were calculated in four age bands: 0-4, 5-9, 10-14, and 15-19 years. The association between HIV infection, age, and sex in children and adolescents with tuberculosis was evaluated using multivariable logistic regression.

RESULTS

Of 719 400 children and adolescents included, 339 112 (47%) were 0-4 year olds. The overall tuberculosis CNR for 0-19 year olds declined by 54% between 2009 and 2016 (incidence rate ratio [IRR] = 0.46; 95% confidence interval [CI], .45-.47). Trends varied by age and HIV, with the smallest reductions (2013-2016) in HIV-positive 0-4 year olds (IRR = 0.90; 95% CI, .85-.95) and both HIV-positive (IRR = .84; 95% CI, .80-.88) and HIV-negative (IRR = 0.89; 95% CI, .86-.92) 15-19 year olds. Compared with 0- to 4-year-old males, odds of HIV coinfection among 15-19 year olds were nearly twice as high in females (adjusted odds ratio [aOR] = 2.49; 95% CI, 2.38-2.60) than in males (aOR = 1.35; 95% CI, 1.29-1.42).

CONCLUSIONS

South Africa's national response to the HIV epidemic has made a substantial contribution to the observed declining trends in tuberculosis CNRs in children and adolescents. The slow decline of tuberculosis CNRs in adolescents and young HIV-positive children is concerning. Understanding how tuberculosis affects children and adolescents beyond conventional age bands and by sex can inform targeted tuberculosis control strategies.

Mortality during tuberculosis treatment in South Africa using an 8-year analysis of the national tuberculosis treatment register

In 2011, the South African HIV treatment eligibility criteria were expanded to allow all tuberculosis (TB) patients lifelong ART. The impact of this change on TB mortality in South Africa is not known. We evaluated mortality in all adults (≥ 15 years old) treated for drug-susceptible TB in South Africa between 2009 and 2016. Using a Cox regression model, we quantified risk factors for mortality during TB treatment and present standardised mortality ratios (SMR) stratified by year, age, sex, and HIV status. During the study period, 8.6% (219,618/2,551,058) of adults on TB treatment died. Older age, male sex, previous TB treatment and HIV infection (with or without the use of ART) were associated with increased hazard of mortality. There was a 19% reduction in hazard of mortality amongst all TB patients between 2009 and 2016 (adjusted hazard ratio: 0.81 95%CI 0.80-0.83). The highest SMR was in 15-24-year-old women, more than double that of men (42.3 in 2016). Between 2009 and 2016, the SMR for HIV-positive TB patients increased, from 9.0 to 19.6 in women, and 7.0 to 10.6 in men. In South Africa, case fatality during TB treatment is decreasing and further interventions to address specific risk factors for TB mortality are required. Young women (15-24-year-olds) with TB experience a disproportionate burden of mortality and interventions targeting this age-group are needed.

Mortality in South African Children and Adolescents Routinely Treated for Tuberculosis

BACKGROUND

In South Africa, tuberculosis (TB) is a leading cause of death among those <20 years of age. We describe changes in TB mortality among children and adolescents in South Africa over a 13-year period, identify risk factors for mortality, and estimate excess TB-related mortality.

METHODS

Retrospective analysis of all patients <20 years of age routinely recorded in the national electronic drug-susceptible TB treatment register (2004-2016). We developed a multivariable Cox regression model for predictors of mortality and used estimates of mortality among the general population to calculate standardized mortality ratios (SMRs).

RESULTS

Between 2004 and 2016, 729 463 children and adolescents were recorded on TB treatment; 84.0% had treatment outcomes and 2.5% (18 539) died during TB treatment. The case fatality ratio decreased from 3.3% in 2007 to 1.9% in 2016. In the multivariable Cox regression model, ages 0 to 4, 10 to 14, and 15 to 19 years (compared with ages 5 to 9 years) were associated with increased risk of mortality, as was HIV infection, previous TB treatment, and extrapulmonary involvement. The SMR of 15 to 19-year-old female patients was more than double that of male patients the same age (55.3 vs 26.2). Among 10 to 14-year-olds and those who were HIV-positive, SMRs increased over time.

CONCLUSIONS

Mortality in South African children and adolescents treated for TB is declining but remains considerable, with 2% dying during 2016. Adolescents (10 to 19 years) and those people living with HIV have the highest risk of mortality and the greatest SMRs. Interventions to reduce mortality during TB treatment, specifically targeting those at highest risk, are urgently needed.

The global burden of tuberculous meningitis in adults: A modelling study

Tuberculous meningitis (TBM) is the most lethal form of tuberculosis. The incidence and mortality of TBM is unknown due to diagnostic challenges and limited disaggregated reporting of treated TBM by existing surveillance systems. We aimed to estimate the incidence and mortality of TBM in adults (15+ years) globally. Using national surveillance data from Brazil, South Africa, the United Kingdom, the United States of America, and Vietnam, we estimated the fraction of reported tuberculosis that is TBM, and the case fatality ratios for treated TBM in each of these countries. We adjusted these estimates according to findings from a systematic review and meta-analysis and applied them to World Health Organization tuberculosis notifications and estimates to model the global TBM incidence and mortality. Assuming the case detection ratio (CDR) for TBM was the same as all TB, we estimated that in 2019, 164,000 (95% UI; 129,000-199,000) adults developed TBM globally; 23% were among people living with HIV. Almost 60% of incident TBM occurred in males and 20% were in adults 25-34 years old. 70% of global TBM incidence occurred in Southeast Asia and Africa. We estimated that 78,200 (95% UI; 52,300-104,000) adults died of TBM in 2019, representing 48% of incident TBM. TBM case fatality in those treated was on average 27%. Sensitivity analysis assuming improved detection of TBM compared to other forms of TB (CDR odds ratio of 2) reduced estimated global mortality to 54,900 (95% UI; 32,200-77,700); assuming instead worse detection for TBM (CDR odds ratio of 0.5) increased estimated mortality to 125,000 (95% UI; 88,800-161,000). Our results highlight the need for improved routine TBM monitoring, especially in high burden countries. Reducing TBM incidence and mortality will be necessary to achieve the End TB Strategy targets.

Notification of relapse and other previously treated tuberculosis in the 52 health districts of South Africa

OBJECTIVE: To investigate the extent to which relapse and other previously treated tuberculosis (TB) contribute to the notified TB burden in South Africa.DESIGN: We conducted an ecological analysis at the level of the 52 South African health districts using national electronic TB register data. We included all bacteriologically confirmed TB cases treated for presumed drug-susceptible TB in 2011. Treatment history information was based on recorded patient categories (new vs. retreatment).RESULTS: Relapse and other previously treated TB cases constituted between 7.6% and 40% (median 17%, interquartile range 12-22) of all bacteriologically confirmed TB cases in the 52 South African districts. Multivariable analysis suggested that districts with higher proportions of previously treated TB cases had higher TB case notification rates (P < 0.001), lower estimates of antenatal human immunodeficiency virus (HIV) prevalence in the district population (P < 0.001) as well as lower HIV co-infection rates (P < 0.001) among new TB cases.CONCLUSION: Relapse and other previously treated TB cases contributed substantially to the notified TB burden in several South African health districts, particularly those with high case notification rates and lower antenatal HIV prevalence. Additional efforts to prevent TB among previously treated people, such as strengthening treatment monitoring and/or secondary preventive therapy, should be considered.

Effect of artemether-lumefantrine policy and improved vector control on malaria burden in KwaZulu-Natal, South Africa

BACKGROUND

Between 1995 and 2000, KwaZulu-Natal province, South Africa, experienced a marked increase in Plasmodium falciparum malaria, fuelled by pyrethroid and sulfadoxine-pyrimethamine resistance. In response, vector control was strengthened and artemether-lumefantrine (AL) was deployed in the first Ministry of Health artemisinin-based combination treatment policy in Africa. In South Africa, effective vector and parasite control had historically ensured low-intensity malaria transmission. Malaria is diagnosed definitively and treatment is provided free of charge in reasonably accessible public-sector health-care facilities.

METHODS AND FINDINGS

We reviewed four years of malaria morbidity and mortality data at four sentinel health-care facilities within KwaZulu-Natal's malaria-endemic area. In the year following improved vector control and implementation of AL treatment, malaria-related admissions and deaths both declined by 89%, and outpatient visits decreased by 85% at the sentinel facilities. By 2003, malaria-related outpatient cases and admissions had fallen by 99%, and malaria-related deaths had decreased by 97%. There was a concomitant marked and sustained decline in notified malaria throughout the province. No serious adverse events were associated causally with AL treatment in an active sentinel pharmacovigilance survey. In a prospective study with 42 d follow up, AL cured 97/98 (99%) and prevented gametocyte developing in all patients. Consistent with the findings of focus group discussions, a household survey found self-reported adherence to the six-dose AL regimen was 96%.

CONCLUSION

Together with concurrent strengthening of vector control measures, the antimalarial treatment policy change to AL in KwaZulu-Natal contributed to a marked and sustained decrease in malaria cases, admissions, and deaths, by greatly improving clinical and parasitological cure rates and reducing gametocyte carriage.

Malaria control--two years' use of insecticide-treated bednets compared with insecticide house spraying in KwaZulu-Natal

OBJECTIVES

The objective of this study was to produce data indicating whether insecticide-treated bednets should replace insecticide house spraying as a malaria control method in South Africa. We report 2 years of preliminary data on malaria incidence comparing areas receiving insecticide-treated bednets and those subjected to house spraying in northern KwaZulu-Natal.

DESIGN, SETTING AND SUBJECTS

In order to measure significant reductions in malaria incidence between the two interventions, a geographical information system (GIS) was used to identify and create seven pairs of geographical blocks (areas) in the malaria high-risk areas of Ndumu and Makanis in Ingwavuma magisterial district, KwaZulu-Natal. Individual blocks were then randomly allocated to either insecticide-treated bednets or house spraying with deltamethrin. Malaria cases were either routinely recorded by surveillance agents at home or were reported to the nearest health facility.

RESULTS AND CONCLUSIONS

The results show that 2 years' use of insecticide-treated bednets by communities in Ndumu and Makanis, KwaZulu-Natal, significantly reduced the malaria incidence both in 1997 (rate ratio (RR) = 0.879, 95% confidence interval (CI) 0.80-0.95, P = 0.04) and in 1998 (RR = 0.667, CI 0.61-0.72, P = 0.0001). Using a t-test, these significant reductions were further confirmed by an assessment of the rate of change between 1996 and 1998, showing a 16% reduction in malaria incidence in blocks using treated bednets and an increase of 45% in sprayed areas (t = 2.534, P = 0.026 (12 df)). In order to decide whether bednets should replace house spraying in South Africa, we need more data on the efficacy of treated bednets, their long-term acceptability and the cost of the two interventions.

Comparison of the cost and cost-effectiveness of insecticide-treated bednets and residual house-spraying in KwaZulu-Natal, South Africa

Residual house-spraying (RHS) has been the mainstay of South African malaria prevention for more than 50 years, but it has been argued that insecticide-treated bednets (ITBN) could be a more effective and appropriate method of control. To provide a rational basis for choosing between the interventions, a trial was conducted during 1998 and 1999 in northern KwaZulu-Natal to collect comparable data on the effectiveness, acceptability and cost of the two interventions. The current practice of house-spraying once a year was compared with ITBN, distributed free to households and retreated annually at several specific centres. The base case results show ITBN to be significantly more effective in preventing malaria cases than RHS (overall adjusted rate ratio of 0.69), and also more costly, with an incremental economic cost per person of ITBN compared with RHS of R8.68 (US$1.42) per year, giving a gross incremental cost per case averted of R111 ($18) (1999 prices). Estimating the number of deaths averted, based on the average case fatality rate, gave a gross incremental cost per death averted of R11 718 ($1915). The additional cases averted were estimated to lead to drug cost savings of around R1 ($0.16) per capita per year, giving a net cost per case averted of R98 ($16), and net cost per death averted of R10 377 ($1696). Although the finding that the economic costs of ITBN were higher than those for RHS was relatively robust to parameter variations, the extent of the cost margin was sensitive to changes in the price and useful life of the net, and the price of the insecticide. Moreover, a switch to ITBN could lead to net financial savings if the price per net fell below $3.57 (R21.85), or if a change in policy allowed a significant reduction in the number of permanent full-time malaria control staff. In view of the greater effectiveness of ITBN, policy makers may view ITBN as a cost-effective use of resources, even if the economic costs are higher. If ITBN are implemented, close monitoring will be required of use, retreatment and useful life of nets, and resistance to insecticides, to assess any change over time in relative cost-effectiveness, and any threat to the role of the programme as a barrier to the spread of malaria transmission to other areas.