Recommendations on modern contact investigation methods for enhancing tuberculosis control [Review article]

Effective contact investigations are paramount to the success of tuberculosis (TB) control in high-risk communities in low TB prevalence countries. National and international guidelines on TB contact investigations are available and vary widely on recommendations. Because of the limitations of traditional contact tracing, new approaches are under investigation, and in some cases in use, to ensure effective TB control in those persons and communities at greatest risk. These non-traditional approaches include the use of social network analysis, geographic information systems and genomics, in addition to the widespread use of genotyping, to better understand TB transmission. Detailed guidelines for the use of these methods during TB outbreaks and in routine follow-up of TB contact investigations do not currently exist despite evidence that they may improve TB control efforts. It remains unclear as to when it is most appropriate and effective to use a network-informed approach alone, or in combination with other methodologies as well as the extent of data collection required to inform practice. TB controllers should consider developing the capacity to facilitate the systematic collection, analysis, and interpretation of contact investigation data using such novel methodologies, particularly in high-risk communities. Further investigation should focus on questionnaire development and adaptation, electronic data management and infrastructure, development of local capability and consultant expertise, and the use of coordinated approaches, including deployment strategies and evaluation.