A core functionality in the design of DAT products is the routine transmission of treatment adherence logs to a centralized database. The mode and frequency of this transmission can vary.
- Some DAT products require sending and receiving SMS messages daily, necessitating users to have access to feature phones and 2G or faster cellular networks.
- Others, such as some Video Observed Therapy (VOT) products, require access to smart phones and the internet through WiFi or 3G/4G/LTE cellular networks.
- Some do not require users to have access cellular phones and use integrated SIM cards to transmit data.
Each DAT design is able to service a subset of the TB market, and the size of this subset can be determined based on requisite access to internet and cellular technologies (ICT). This page will consider trends and implications of differential access to feature phones and smart phones across endemic geographies. Use the interactive map visualization below to explore these trends.
The aggregate impact of inconsistent ICT access on the global DAT for TB market is illustrated in the Sankey diagram below. Use the toggles in the “Options” box to review the diagram by WHO Regions or by high TB burden countries. In 2019, out of 5.9 million persons diagnosed with TB, we estimate that ~4.6 million had access to cellphones, of which only ~2 million had access to smartphones. Roughly 1.2 million persons lack access to any kind of phone and is not serviceable by most existing DAT designs which require access to cellphones.
DAT designs that require access to smartphones can only service a relatively small segment of the potential addressable market. This is especially true across high burden LMICs in South-East Asia and Africa regions where smartphone ownership is still relatively rare. In India, the largest market globally, only ~20% is currently able to use DATs that require a smartphone. Nevertheless, these products will likely find a niche in the global market due to their simplicity and desirability for users. Smartphone-based DAT are most applicable for use in HIC settings and urban areas of LMICs where internet access and smartphone ownership is highest.
DAT designs that require access to feature phones is most suited to service the needs of the TB market. Cellphone ownership globally, and particularly in the substantial Asia market, is relatively high. In China, the second largest market, nearly 90% is currently able to use DATs that require feature phone functionalities. Across all LMICs, access to feature phones is also expected to grow faster than smartphones, ensuring better long-term growth prospects for this DAT type.
Ultimately the TB market will need to be serviced by a diversity of DAT types, including types that are not currently on the market. Integrating DAT into routine TB management equitably will require reaching patients across the entire spectrum of ICT access. The trickiest market segment to reach is the ~1.2 million globally of persons diagnosed with TB without access to cellular technologies. More operational research may be necessary to understand the best product and/or design to meet this unmet need. While this market segment may seem small and offer limited incentive to DAT manufacturers for innovation, in reality, products which do not require cell phone access would have maximal reach and could service the needs of all other ICT market segments.
An alternative strategy to address lack of ICT access is to integrate provision of necessary ICT (cell/smart phones + SIM cards) along with associated DAT. While this has been done in the context of research projects, it is unlikely to be feasible and sustainable at scale.