Tuberculosis surveillance in Cape Town, South Africa: an evaluation

The differential impact of HIV and antiretroviral therapy on gender-specific tuberculosis rates

OBJECTIVE

To assess the impact of the HIV epidemic and the rollout of antiretroviral therapy (ART) from 2004 on the gender-specific TB burden in Cape Town, we investigated temporal changes in TB notification rates, the HIV-associated relative risk of TB and the population attributable risk fraction (PAF) of HIV by gender.

METHODS

Annual TB notifications, mid-year population and HIV prevalence estimates were used to calculate rates per 100 000 population stratified by gender and HIV. Annual rate ratios (RR) of TB associated with HIV and PAF were calculated by gender.

RESULTS

Pre-HIV TB notification rates were lower among women than men (146/100 000 vs. 247/100 000). With the onset of the HIV, epidemic rates increased 5.3-fold in women (to 778/100 000) and 3.7-fold in men (to 917/100 000) to a peak in 2008, after which they declined by 25% in women (to 634/100 000) and 18% in men (to 755/100 000) by 2014. The HIV-associated RR of TB was 25% higher in women than in men in 2006 (25 vs. 20), but decreased to the same level in 2014. HIV PAF declined between 2008 and 2014 from 56% to 50% and from 40% to 38% in women and men, respectively.

CONCLUSIONS

The HIV epidemic led to greater relative increases in TB rates among women than men. The increased HIV-associated TB risk in women could be compatible with removal of the biological protection of female gender by HIV infection. The decline in RR and PAF in HIV-positive women could be explained by increasing ART usage reversing female gender-related susceptibility.

Evaluating the electronic tuberculosis register surveillance system in Eden District, Western Cape, South Africa, 2015

Background: Tuberculosis (TB) surveillance data are crucial to the effectiveness of National TB Control Programs. In South Africa, few surveillance system evaluations have been undertaken to provide a rigorous assessment of the platform from which the national and district health systems draws data to inform programs and policies.

Objective: Evaluate the attributes of Eden District’s TB surveillance system, Western Cape Province, South Africa.

Methods: Data quality, sensitivity and positive predictive value were assessed using secondary data from 40,033 TB cases entered in Eden District’s ETR.Net from 2007 to 2013, and 79 purposively selected TB Blue Cards (TBCs), a medical patient file and source document for data entered into ETR.Net. Simplicity, flexibility, acceptability, stability and usefulness of the ETR.Net were assessed qualitatively through interviews with TB nurses, information health officers, sub-district and district coordinators involved in the TB surveillance.

Results: TB surveillance system stakeholders report that Eden District’s ETR.Net system was simple, acceptable, flexible and stable, and achieves its objective of informing TB control program, policies and activities. Data were less complete in the ETR.Net (66–100%) than in the TBCs (76–100%), and concordant for most variables except pre-treatment smear results, antiretroviral therapy (ART) and treatment outcome. The sensitivity of recorded variables in ETR.Net was 98% for gender, 97% for patient category, 93% for ART, 92% for treatment outcome and 90% for pre-treatment smear grading.

Conclusions: Our results reveal that the system provides useful information to guide TB control program activities in Eden District. However, urgent attention is needed to address gaps in clinical recording on the TBC and data capturing into the ETR.Net system. We recommend continuous training and support of TB personnel involved with TB care, management and surveillance on TB data recording into the TBCs and ETR.Net as well as the implementation of a well-structured quality control and assurance system.

A systems-based assessment of the PrePex device adverse events active surveillance system in Zimbabwe

Background

Voluntary Medical Male Circumcision (VMMC) is an effective method for HIV prevention and the World Health Organization (WHO) has recommended its expansion in 14 African countries with a high prevalence of HIV and low prevalence of male circumcision. The WHO has recently pre-qualified the PrePex device, a non-surgical male circumcision device, which reduces procedure time, can increase acceptability of VMMC, and can expand the set of potential provider cadres. The PrePex device was introduced in Zimbabwe as a way to scale-up VMMC services in the country. With the rapid scale-up of the PrePex device, as well as other similar devices, a strong surveillance system to detect adverse events (AE) is needed to monitor the safety profile of these devices. We performed a systems-based evaluation of the PrePex device AE active surveillance system in Zimbabwe.

Methods

The evaluation was based on the Centers for Disease Control and Prevention’s Updated Guidelines for Evaluating Public Health Surveillance Systems. We adapted these guidelines to fit our local context. The evaluation incorporated the review of the standard operating procedures and surveillance system documents. Additionally, structured, in-person interviews were performed with key stakeholders who were users of the surveillance system at various levels. These key stakeholders were from the Ministry of Health, implementing partners, and health facilities in Harare.

Results

Clients were requested to return to the facility for follow-up on days 7, 14 and 49 after placement of the device. In the event of a severe AE, a standard report was generated by the health facility and relayed to the Ministry of Health Child and Care and donor agencies through predefined channels within 24 hours of diagnosis. Clinic staff reported difficulties with the amount of documentation required to follow up with clients and to report AEs. The surveillance system’s acceptability among users interviewed was high, and users were motivated to identify all possible AEs related to this device. The surveillance system was purely paper-based and both duplicate and discrepant reporting forms between sites were identified.

Conclusion

The PrePex AE active surveillance system was well accepted among participants in the health system. However, the amount of documentation which was required to follow-up with patients was a major barrier within the system, and might lead to decreased timeliness and quality of reporting. A passive surveillance system supported by electronic reporting would improve acceptance of the program.

Comparing laboratory surveillance with the notifiable diseases surveillance system in South Africa

OBJECTIVE

The aim of this study was to compare laboratory surveillance with the notifiable diseases surveillance system (NDSS) in South Africa.

METHODS

Data on three tracer notifiable diseases - measles, meningococcal meningitis, and typhoid - were compared to assess data quality, stability, representativeness, sensitivity and positive predictive value (PPV), using the Wilcoxon and Chi-square tests, at the 5% significance level.

RESULTS

For all three diseases, fewer cases were notified than confirmed in the laboratory. Completeness for the laboratory system was higher for measles (63% vs. 47%, p<0.001) and meningococcal meningitis (63% vs. 57%, p<0.001), but not for typhoid (60% vs. 63%, p=0.082). Stability was higher for the laboratory (all 100%) compared to notified measles (24%, p<0.001), meningococcal meningitis (74%, p<0.001), and typhoid (36%, p<0.001). Representativeness was also higher for the laboratory (all 100%) than for notified measles (67%, p=0.058), meningococcal meningitis (56%, p=0.023), and typhoid (44%, p=0.009). The sensitivity of the NDSS was 50%, 98%, and 93%, and the PPV was 20%, 57%, and 81% for measles, meningococcal meningitis, and typhoid, respectively.

CONCLUSIONS

Compared to laboratory surveillance, the NDSS performed poorly on most system attributes. Revitalization of the NDSS in South Africa is recommended to address the completeness, stability, and representativeness of the system.

Survey of the perceptions of key stakeholders on the attributes of the South African Notifiable Diseases Surveillance System

Background

An effective and efficient notifiable diseases surveillance system (NDSS) is essential for a rapid response to disease outbreaks, and the identification of priority diseases that may cause national, regional or public health emergencies of international concern (PHEICs). Regular assessments of country-based surveillance system are needed to enable countries to respond to outbreaks before they become PHEICs. As part of a broader evaluation of the NDSS in South Africa, the aim of the study was to determine the perceptions of key stakeholders on the national NDSS attributes of acceptability, flexibility, simplicity, timeliness and usefulness.

Methods

During 2015, we conducted a nationally representative cross-sectional survey of communicable diseases coordinators and surveillance officers, as well as members of NDSS committees. Individuals with less than 1 year experience of the NDSS were excluded. Consenting participants completed a self-administered questionnaire. The questionnaire elicited information on demographic information and perceptions of the NDSS attributes. Data were analysed using descriptive statistics and the unconditional logistic regression model.

Results

Most stakeholders interviewed (53 %, 60/114) were involved in disease control and response. The median number of years of experience with the NDSS was 11 years (inter-quartile range (IQR): 5 to 20 years). Regarding the NDSS attributes, 25 % of the stakeholders perceived the system to be acceptable, 51 % to be flexible, 45 % to be timely, 61 % to be useful, and 74 % to be simple. Health management stakeholders perceived the system to be more useful and timely compared to the other stakeholders. Those with more years of experience were less likely to perceive the NDSS system as acceptable (OR 0.91, 95 % CI: 0.84–1.00, p = 0.041); those in disease detection were less likely to perceive it as timely (OR 0.10, 95 % CI: 0.01–0.96, p = 0.046) and those participating in National Outbreak Response Team were less likely to perceive it as useful (OR 0.38, 95 % CI: 0.16–0.93, p = 0.034).

Conclusion

The overall poor perceptions of key stakeholder on the system attributes are a cause for concern. The study findings should inform the revitalisation and reform of the NDSS in South Africa, done in consultation and partnership with the key stakeholders.

Electronic supplementary material

The online version of this article (doi:10.1186/s12889-016-3781-7) contains supplementary material, which is available to authorized users.

The other side of surveillance: Monitoring, application, and integration of tuberculosis data to guide and evaluate programme activities in South Africa

BACKGROUND

The importance of using surveillance data to monitor and evaluate programme activities has been emphasised in international policies for tuberculosis (TB) control.

OBJECTIVES

A survey was conducted to assess the use of TB surveillance data to monitor and guide TB programme activities in South Africa (SA).

METHODS

As part of an evaluation of the SA national TB surveillance system, semi-structured interviews were conducted among TB staff at health facilities and offices in three provinces. At each site, all persons involved with TB care, management and surveillance were invited to participate.

RESULTS

At least one person (range 1 - 4) was interviewed at 47/54 health facilities (87.0%), 11/13 subdistrict and district TB offices (84.6%), 2/3 provincial TB offices (66.7%), and at the national level (1/1, 100.0%). Of 119 TB staff, 64.7% recognised the purpose of TB surveillance as guiding programme planning, implementation and evaluation. However, only 16.0% reported using data to measure disease burden, 8.4% to monitor trends, and 9.2% to inform resource allocation. The majority reported using TB management tools provided by the national programme, but 44.5% also described using additional tools. Personnel mentioned the need for dedicated surveillance staff, training on recording and reporting, improved computer access, and methods to apply information from surveillance data to the programme.

CONCLUSIONS

The majority of TB staff understood the purpose of surveillance but did not routinely use data to guide programme planning, implementation and evaluation. Training and supporting TB staff to utilise surveillance data will help improve the TB surveillance system.

Completeness and Reliability of the Republic of South Africa National Tuberculosis (TB) Surveillance System

Background

Accurate surveillance data are paramount to effective TB control. The Republic of South Africa’s National TB Control Program (NTP) has conducted TB surveillance since 1995 and adopted the Electronic TB Register (ETR) in 2005. This evaluation aimed to determine the completeness and reliability of data in the Republic of South Africa’s TB Surveillance System.

Methods

Three of nine provinces, three subdistricts per province, and 54 health facilities were selected by stratified random sampling. At each facility, 30 (or all if <30) patients diagnosed in Quarter 1 2009 were randomly selected for review. Patient information was evaluated across two paper and four electronic sources. Completeness of program indicators between paper and electronic sources was compared with chi-square tests. The kappa statistic was used to evaluate agreement of values.

Results

Over one-third (33.7 %) of all persons with presumptive TB recorded as smear positive in the TB Suspect Register did not have any records documenting notification, treatment, or management for TB disease. Of 1339 persons with a record as a TB patient at the facility, 1077 (80 %) were recorded in all data sources. Over 98 % of records contained complete age and sex data. Completeness varied for HIV status (53-86 %; p < 0.001) and DOT during the intensive phase of treatment (17-54 %; p < 0.001). Agreement for sex was excellent across sources (kappa 0.94); moderate for patient type (0.78), treatment regimen (0.79), treatment outcome (0.71); and poor for HIV status (0.33).

Conclusions

The current evaluation revealed that one-third of persons diagnosed with TB disease may not have been notified of their disease or initiated on treatment (‘initial defaulters’). The ETR is not capturing all TB patients. Further, among patients with a TB record, completeness and reliability of information in the TB Surveillance System is inconsistent across data sources. Actions are urgently needed to ensure that all diagnosed patients are treated and managed and improve the integrity of surveillance information.