The results of a large-scale community-randomized trial, which were presented at the 42nd World Conference on Lung Health in Lille, France show that the Zambia South Africa TB and AIDS Reduction (ZAMSTAR) study's "Household Counselling" intervention reduced the prevalence of culture positive tuberculosis by 22% compared to the communities that did not receive the intervention.
The ZAMSTAR study took place in 24 communities across Zambia and in the Western Cape Province of South Africa and it sought to test ways to interrupt the transmission of TB in communities with a high burden of both TB and HIV.
"In the era of HIV, this is the first community-randomised trial of a public health intervention to be shown to have an impact on the epidemiology of TB at community-level," said Dr. Peter Godfrey-Faussett, one of three ZAMSTAR Principal Investigators and Professor of Infectious Diseases and International Health at London School of Hygiene and Tropical Medicine (LSHTM).
Rates of TB were compared in communities through a large-scale prevalence survey. A total of roughly 1 million individuals were touched by the ZAMSTAR interventions in the two study countries and the interventions cost less than one US dollar per person per year to implement.
During the three-year intervention phase (2006 - 2009) all ZAMSTAR communities (in conjunction with the district and provincial health services) received support to improve TB & HIV care and service integration, while most ZAMSTAR communities received one or both interventions: enhanced TB case finding and the unpacking of concerns about TB & HIV within households and facilitating prompt diagnosis and treatment (referred to as household counselling).
The ZAMSTAR study was carried out by a consortium of three institutions, Zambia AIDS Related TB (ZAMBART) Project, Desmond Tutu TB Centre (DTTC) at the Stellenbosch University and the London School of Hygiene and Tropical Medicine (LSHTM), as one of three large studies within the Consortium to Respond Effectively to the AIDS and TB Epidemics (CREATE). Funding for this $27 million study came from the Bill and Melinda Gates Foundation.
In addition to the reduced prevalence rate, children living in the communities that received the household counselling intervention were half as likely to become infected with TB.
The trial also uncovered that many people with TB do not seek health services when they are ill and often when they do go, the clinic staff do not suspect TB readily enough. If adults are not diagnosed and treated, they can infect children. The trial found that TB transmission rates were still higher than all previous community-based surveys in Africa, with up to one-third of grade 1 - 3 school-children already infected with TB.
"In these communities, TB and HIV affect the entire household, so you need to involve the not only the TB patient but his or her entire family," said Dr. Helen Ayles, ZAMSTAR Principal Investigator and Project Coordinator for ZAMBART. "Over 9,000 households were visited, around one-in-fifteen across the household counselling intervention communities."
Furthermore, ZAMSTAR employed many individuals who lived in the communities where the interventions were conducted. The ZAMSTAR teams conducted highly visible activities such as street dramas, songs and dances and encouraging people to submit sputum samples for TB testing. Around 25% of all the most infectious (sputum smear positive) cases that were diagnosed in the "Enhanced Case Finding" communities were found because of the intervention.
"ZAMSTAR really was an amazing partnership between researchers, communities and health services and the interventions were both well-received and appreciated by the communities in which we worked," said Dr. Nulda Beyers, ZAMSTAR Principal Investigator and Director of the DTTC.
In addition, ZAMSTAR leaves a legacy of hundreds of research assistants, counsellors and clinic staff who were trained through ZAMSTAR and who now have a greater understanding not only of TB and HIV but also of community-based research, ethics and international cooperation.
Despite the increased investments in TB control over the past decade, ZAMSTAR shows that TB is still a devastating disease for far too many people and their families. This could be due to many people with TB nowadays having mild or minor symptoms, a surprising result ZAMSTAR has also shown.
"TB is sometimes seen as an unavoidable part of life in poor communities. We need to improve and strengthen our health services, we need better methods to diagnose TB in clinics and we need people affected by TB, usually in poor communities, to demand that things change," said Dr. Godfrey-Faussett.
While work continues on new TB drugs and vaccines, ZAMSTAR's results show that stronger links need to be formed between clinics and households and communities and these links could have a positive impact on TB control programmes. The work of the ZAMSTAR study has the potential to translate into real reductions in the overall burden of TB in high-burden areas.
About The Consortium to Respond Effectively to the AIDS/TB Epidemic
Funded by a grant from the Bill and Melinda Gates Foundation in 2002, CREATE - the Consortium to Respond Effectively to the AIDS/TB Epidemic - is a consortium of leading experts in TB and HIV who design novel public health interventions to reduce the burden of HIV-related TB at the population level.
The Consortium is led by the Johns Hopkins University Center for Tuberculosis Research, in Maryland, U.S.A., and includes the following partners:
- Aurum Institute for Health Research - Johannesburg, South Africa
- Desmond Tutu Centre at Stellenbosch University - Tygerberg, South Africa
- Municipal Health Secretariat of Rio de Janeiro - Rio de Janeiro, Brazil
- London School of Hygiene and Tropical Medicine - London, England
- ZAMBART Project - Lusaka, Zambia
- Stop TB Partnership, WHO
Led by Dr. Richard Chaisson, CREATE hopes to transform global policies for TB/HIV through evidence-based advocacy.
About London School of Hygiene and Tropical Medicine
The London School of Hygiene & Tropical Medicine (LSHTM) is a renowned research-led postgraduate institution of public health and global health. Its mission is to improve health in the UK and worldwide through the pursuit of excellence in research, postgraduate teaching and advanced training in national and international public health and tropical medicine, and through informing policy and practice in these areas. Part of the University of London, the School is the largest institution of its kind in Europe with a remarkable depth and breadth of expertise encompassing many disciplines associated with public health. www.lshtm.ac.uk
About Desmond Tutu TB Centre
The Desmond Tutu TB Centre is an academic research centre of the Department of Paediatrics and Child Health, Faculty of Health Sciences. It has as its mission the improvement of the health of vulnerable groups through influencing policy based on new knowledge created by research focusing on health, mainly TB and HIV. To achieve this, the Centre works closely with the South African Department of Health and the local communities. It provides training to academic and health services staff, builds capacity in the University and the Department of Health, provides service to communities and advocates for TB and health. Himself a former TB sufferer, Archbishop Desmond Tutu champions tuberculosis research and care. He is also the patron of the on-campus Tygerberg Children's Hospital.
About ZAMBART Project
The Zambia AIDS Related Tuberculosis (ZAMBART) Project has conducted research into the dual TB/HIV epidemic for 20 years in Zambia. In 2004 ZAMBART established itself as a Zambian NGO from a collaboration between the University of Zambia School of Medicine and the London School of Hygiene and Tropical Medicine, and it is now based in the University of Zambia School of Medicine Campus. ZAMBART now collaborates closely with government, non-governmental and academic institutions within Zambia, Africa and the rest of the world. ZAMBART is also committed to increasing Zambian research capacity.