What can we learn from mapping the burden of tuberculosis in Ho Chi Minh City, Vietnam

Tuberculosis (TB), though an ancient disease, remains a global health crisis disproportionately affecting the most disadvantaged in the poorest countries. Ruan Spies (South Africa & Brasenose, 2022) is all but too familiar with the devastating consequences of TB through his work as a medical doctor in South Africa, where TB is a major cause of death and disability. Here he reflects on his research in Vietnam, another country with a high burden of TB, which aimed to describe the burden and distribution of TB in the country’s largest metropolis – Ho Chi Minh City. 

According to the latest edition of the World Health Organisation’s Global TB Report, 10.6 million people fell ill from TB in 2021, 1.6 million of whom died. 90% of this burden occurs in just 30 low-and-middle-income countries. In the Global North TB or ‘consumption’ has been romanticised as a historical, now extinct, disease which claimed the lives of intellectuals, writers and poets. In the Global South, TB-related suffering remains an everyday reality. Significant progress has been made in reducing the global burden of TB over the last century but has at times stalled, most notably following the HIV/AIDS epidemic and the COVID-19 pandemic. When global health is vulnerable TB thrives.

TB is a complex problem to solve. Foremost, the social determinants of health need to be addressed, but alleviating poverty continues to be a painstakingly slow process. In the meantime, research and innovation into our understanding of the disease and improved diagnostics and therapeutics are essential. An old saying goes “What gets measured, gets done”. This is where epidemiology becomes important – if we cannot understand the determinants and distribution of a disease, we will never be able to control it.

In May 2023, I travelled to Ho Chi Minh City, formerly Saigon, to work with researchers at the Oxford University Clinical Research Unit (OUCRU) and to conduct research as part of my dissertation for the MSc in Global Health Science and Epidemiology. Ho Chi Minh City is Vietnam’s largest metropolis with a population approximating nearly 10 million people. The country also has one of the world’s largest burdens of TB and multi-drug resistant TB. Despite this, no recent studies describe the burden of TB in the city, represented by the incidence of the disease and the characteristics of people with TB, nor do any previous studies describe the spatial distribution of the disease within the city. The descriptions are crucial starting points for further research and for TB control efforts. Contextually relevant solutions require local data. For example, understanding where the burden of TB is greatest in the city may help inform policymakers and local health authorities when deciding where to locate healthcare facilities. Active case finding, where healthcare workers proactively screen and identify potential TB cases in communities before they are sick enough to need to seek healthcare, may prove to be a crucial tool in interrupting TB transmission and could also be optimised by spatial targeting.

We analysed data from all TB cases recorded in Ho Chi Minh City between 2020 and 2023. We demonstrated that TB incidence was highly spatially heterogeneous with hot spots of disease occurring in the central parts of the city for both drug-susceptible and multi-drug resistant TB. The geographically overlapping nature of the drug-susceptible and multi-drug-resistant TB epidemics also raised interesting questions about how drug resistance is acquired – questions we hope to explore with the use of whole genome sequencing-derived genetic data in future.

Travelling to Ho Chi Minh City was an experience I’ll remember forever. In the words of Anthony Bourdain, “Motorbike exhausts, fish sauce, the far-away smell of something… is that pork?...grilling over charcoal. Vietnam. It could be no place else.” While initially overwhelmed by the city of 10 million people and nearly 10 million motorbikes, where I was more nervous about crossing the road than even my Rhodes Scholarship interview, I quickly felt enlivened by the city’s energy and vibrancy which pulled me in from every direction. I walked the bustling streets of District 1, seemingly in perpetual motion, and enjoyed the tranquillity of the Saigon River, imagining all it had witnessed and the stories it could tell. I visited the War Remnants Museum and learnt about atrocities too quickly forgotten but also resilience that endures. Every street provided delicious foods like Bánh mì and Phở and some of the best coffee I had ever tasted (at prices that made coming back to the UK and buying coffee from Pret-A-Manger a soul-destroying experience).

Travelling to Vietnam, as a South African, to work on TB research (with a British supervisor) initially felt a bit…odd. Global Health and Tropical Medicine as disciplines have some sticky colonial roots and I was cautious about being part of a research system that was extractive – benefitting the careers and livelihoods of academics in an ivory tower in the Global North at the expense of people with disease in the Global South. I was quickly reassured, however, upon learning about OUCRU’s vision, mission and priorities. Vietnam is an extraordinary country, developing rapidly following widespread poverty in the post-American war era, and has become a regionally and internationally important centre of commerce and industry. The country is affected by many of the most important diseases worldwide, in terms of their global burden, and thus provides a unique setting in which locally important research has tremendous global relevance. OUCRU has produced numerous practice-changing scientific achievements. Central to the unit’s vision, however, has been the training of Vietnamese scientists and the development of local research infrastructure and capacity. OUCRU has managed to combine local interests and international expertise and resources to create a world-class Vietnamese research unit, in the heart of Vietnam.

The opportunity to work with the TB group at OUCRU, which is active at the cutting edge of translational research, was not only intellectually nourishing but career-defining. I had the opportunity to join the group’s academic meetings, discuss TB with field-leading researchers and bounce ideas off the group members, strengthening the quality of my own work. I also had the opportunity to join clinical rounds at the neighbouring Hospital for Tropical Diseases – an instructive first return to the clinical environment after temporarily hanging up my stethoscope on departure to Oxford in September 2022. Most importantly, I was able to expand my knowledge and skills in a field that I’m passionate about – knowledge and skills I hope to apply towards the fight against TB in South Africa and globally. I was excited to travel into the office every morning (it may have helped that my ride in was on the back of a motorbike!).

I travelled to Ho Chi Minh City to conduct research as part of my Master’s dissertation. I left a few weeks later having accomplished so much more. As someone who was not particularly well-travelled, I could never have guessed how enriching experiencing new sights, smells, tastes, scenes, people and cultures could be. I formed lasting relationships, professional and personal, and I was inspired to keep fighting the good fight against TB. In the 2023/24 academic year I will enrol for a DPhil in Clinical Medicine where I will work with the TB group at OUCRU to try to answer the question ‘How do people acquire multi-drug resistant TB?’ I can’t wait to go back.

I am beyond grateful to have received the Murray Speight grant which supported my travel to Ho Chi Minh City and allowed me to work with researchers at OUCRU as part of my MSc dissertation.