Research themes

Active Case Finding

Active case finding is the process of systematically searching for cases of active and latent TB in high risk groups. This is done in place of passive case finding, which waits for individuals to develop symptoms or signs of active disease and present themselves for medical attention.

Despite existing NTP services covering an estimated 83% of Viet Nam’s TB burden, many people with TB are still missed and those who are treated in routine settings often present with significant delays. Community TB case finding activities were established by FIT as an extension of the National TB Program in 6 districts across Ho Chi Minh City to increase TB treatment rates and promote early case finding.

Active Case Finding

Active case finding is the process of systematically searching for cases of active and latent TB in high risk groups. This is done in place of passive case finding, which waits for individuals to develop symptoms or signs of active disease and present themselves for medical attention.

Despite existing NTP services covering an estimated 83% of Viet Nam’s TB burden, many people with TB are still missed and those who are treated in routine settings often present with significant delays. Community TB case finding activities were established as an extension of the National TB Program in 6 districts across Ho Chi Minh City to increase TB treatment rates and promote early case finding.

TB in the Private Sector

Studies indicate that fewer people are treated for vTB in the private sector of Viet Nam than other Asian countries. Yet, anecdotal evidence indicates large numbers of people are still accessing private-sector TB care owing to its convenience and privacy.

We established a public-provider interface agency (PPIA) with a network of over 167 private providers across two districts of Ho Chi Minh City. Participating providers can distribute vouchers to their clients for reduced-rate chest X-rays (CXRs) at private radiology labs. In addition, we engaged with private providers to find people with TB who are ‘missed’ by public-sector TB services are seeking care in the private sector.

TB in the Private Sector

Studies indicate that fewer people are treated for vTB in the private sector of Viet Nam than other Asian countries. Yet, anecdotal evidence indicates large numbers of people are still accessing private-sector TB care owing to its convenience and privacy.

We established a public-provider interface agency (PPIA) with a network of over 167 private providers across two districts of Ho Chi Minh City. Participating providers can distribute vouchers to their clients for reduced-rate chest X-rays (CXRs) at private radiology labs. In addition, we engaged with private providers to find people with TB who are ‘missed’ by public-sector TB services are seeking care in the private sector.

TB Diagnostics

A high proportion of people with TB do not report TB symptoms, and they can only be detected through chest X-ray screening. In response, several computer-assisted reading (CAR) software programs have been developed to identify chest X-ray abnormalities in the absence of a radiologist.

We assembled a library of 1,181 CXR images from community-based mobile X-ray screening events in Ho Chi Minh City. This library was re-read by an experienced radiologist and also processed by six CAR software programs: Artelus, CAD4TB, Lunit, qXR, SemanticMD and XrayAME. Many CAR software programs are now available to TB programs and several are approaching the performance of expert human readers.

TB Diagnostics

A high proportion of people with TB do not report TB symptoms, and they can only be detected through chest X-ray screening. In response, several computer-assisted reading (CAR) software programs have been developed to identify chest X-ray abnormalities in the absence of a radiologist.

We assembled a library of 1,181 CXR images from community-based mobile X-ray screening events in Ho Chi Minh City. This library was re-read by an experienced radiologist and also processed by six CAR software programs: Artelus, CAD4TB, Lunit, qXR, SemanticMD and XrayAME. Many CAR software programs are now available to TB programs and several are approaching the performance of expert human readers.

Treatment Support and Social Protection

To provide treatment support and social protection, we conducted a pilot study providing Social Health Insurance (SHI) and cash transfers to patients with drug-susceptible TB and their households in Ho Chi Minh City

Qualitative interviews were conducted to assess the acceptability of the provision of cash transfers and health insurance. 120 patients were enrolled in the pilot study. Social Health Insurance was obtained for 48 individuals who did not have insurance at TB treatment initiation and cash was provided to support treatment for 6 months of TB care. While this study is still ongoing, we plan to conduct patient cost surveys, integrate support packages for MDR-TB patients, and expand social support activities to Hanoi.

Treatment Support and Social Protection

To provide treatment support and social protection, we conducted a pilot study providing Social Health Insurance (SHI) and cash transfers to patients with drug-susceptible TB and their households in Ho Chi Minh City

Qualitative interviews were conducted to assess the acceptability of the provision of cash transfers and health insurance. 120 patients were enrolled in the pilot study. Social Health Insurance was obtained for 48 individuals who did not have insurance at TB treatment initiation and cash was provided to support treatment for 6 months of TB care. While this study is still ongoing, we plan to conduct patient cost surveys, integrate support packages for MDR-TB patients, and expand social support activities to Hanoi.

Health Economics

TB is a heavy economic burden for patients and society. There is already extensive evidence on the cost-effectiveness of TB care and prevention. To examine this further, we conducted studies to assess the social return on investment (SROI) of incremental case finding, and have evaluated the health systems cost of active case finding.

We conducted a mixed-method study that estimated the societal benefit of a community-based TB case finding and patient support intervention. We constructed a SROI model according to the methodology of Social Value UK, which entails mapping and monetizing value drivers, adjusting crude impact for four counterfactuals, and calculating the SROI based on the present values of benefits and costs in a 5-year discounted cash flow model.
In addition, a separate study we conducted looked at active case finding costs in six intervention districts as compared to six control districts of Ho Chi Minh City. Active case finding activities consisted of contact investigation and systematic screening of vulnerable populations. 

Health Economics

TB is a heavy economic burden for patients and society. There is extensive evidence on the cost effectiveness of TB care and prevention, so we have conducted studies to assess the social return on investment (SROI) of incremental case finding, and have evaluated the health systems cost of active case finding.

We conducted a mixed-method study that estimated the societal benefit of a community-based TB case finding and patient support intervention. We constructed a SROI model according to the methodology of Social Value UK, which entails mapping and monetizing value drivers, adjusting crude impact for four counterfactuals, and calculating the SROI based on the present values of benefits and costs in a 5-year discounted cash flow model.
In addition, a separate study we conducted looked at active case finding costs in six intervention districts as compared to six control districts of Ho Chi Minh City. Active case finding activities consisted of contact investigation and systematic screening of vulnerable populations. 

TB in Vulnerable Populations

The vulnerable populations in Vietnam that we try to reach include older people, migrants, and injecting drug users. There is evidence that certain vulnerable populations like these have a much greater likelihood of poor treatment outcomes.

In Viet Nam, older people (aged 55+ years) have high rates of TB and a 20% increased risk of being missed by public-sector TB services, frequently owing to their limited mobility and dependency on family members. We conducted over 80 days of mobile chest X-ray events and this community-based screening initiative resulted in improved TB detection and treatment, particularly for older people.

We measured the association between temporary residency and treatment success (TS) and loss to follow-up (LTFU) in two urban districts of Ho Chi Minh City over six years. Temporary residents in Viet Nam, particularly those migrating across provincial borders with short-term residency status, are more vulnerable to lower TS and higher LTFU. Programs may mitigate these effects through patient support interventions.

We launched the DRIVE study (DRug Use and Infections in Hai Phong Viet Nam Among Persons Who Inject Drugs) which verbally screened injecting drug users for TB symptoms. The rate of TB in our study population was six times higher than Viet Nam’s estimated TB prevalence rate (289/100,000 population).

Evaluation of a community-based X-ray screening initiative to improve TB detection among older people in Ho Chi Minh City, Viet Nam:

High yield of tuberculosis from systematic screening among active intravenous drug users in Hai Phong, Viet Nam:

TB in Vulnerable Populations

The vulnerable populations in Vietnam that we try to reach include older people, migrants, and injecting drug users. There is evidence that certain vulnerable populations like these have a much greater likelihood of poor treatment outcomes.

In Viet Nam, older people (aged 55+ years) have high rates of TB and a 20% increased risk of being missed by public-sector TB services, frequently owing to their limited mobility and dependency on family members. We conducted over 80 days of mobile chest X-ray events and this community-based screening initiative resulted in improved TB detection and treatment, particularly for older people.

We measured the association between temporary residency and treatment success (TS) and loss to follow-up (LTFU) in two urban districts of Ho Chi Minh City over six years. Temporary residents in Viet Nam, particularly those migrating across provincial borders with short-term residency status, are more vulnerable to lower TS and higher LTFU. Programs may mitigate these effects through patient support interventions.

We launched the DRIVE study (DRug Use and Infections in Hai Phong Viet Nam Among Persons Who Inject Drugs) which verbally screened injecting drug users for TB symptoms. The rate of TB in our study population was six times higher than Viet Nam’s estimated TB prevalence rate (289/100,000 population).

Evaluation of a community-based X-ray screening initiative to improve TB detection among older people in Ho Chi Minh City, Viet Nam:

High yield of tuberculosis from systematic screening among active intravenous drug users in Hai Phong, Viet Nam:

TB Infection Testing and Treatment

The current latent TB infection (LTBI) treatment regimen in Viet Nam is nine months of isoniazid for adults. posing a major challenge for LTBI treatment adherence and completion.

A population-level TB screening campaign was conducted on the island of Cu Lao Cham. We screened island residents for LTBI (tuberculin skin test ≥10mm). And treated those who were  eligible with daily rifampicin and isoniazid for 3 months (3HR). We found that people with LTBI who were treated with 3HR had high treatment completion rates and low rates of adverse events. This suggests that 3HR can be safely administered at the population-level and that follow-up care can be managed by the existing health system benefits and costs in a 5-year discounted cash flow model.
In addition, a separate study we conducted looked at active case finding costs in six intervention districts as compared to six control districts of Ho Chi Minh City. Active case finding activities consisted of contact investigation and systematic screening of vulnerable populations. 

TB Infection Testing and Treatment

The current latent TB infection (LTBI) treatment regimen in Viet Nam is nine months of isoniazid for adults. posing a major challenge for LTBI treatment adherence and completion.

A population-level TB screening campaign was conducted on the island of Cu Lao Cham. We screened island residents for LTBI (tuberculin skin test ≥10mm). And treated those who were  eligible with daily rifampicin and isoniazid for 3 months (3HR). We found that people with LTBI who were treated with 3HR had high treatment completion rates and low rates of adverse events. This suggests that 3HR can be safely administered at the population-level and that follow-up care can be managed by the existing health system benefits and costs in a 5-year discounted cash flow model.
In addition, a separate study we conducted looked at active case finding costs in six intervention districts as compared to six control districts of Ho Chi Minh City. Active case finding activities consisted of contact investigation and systematic screening of vulnerable populations.