Five Questions with Cosette Audi

Isn’t tuberculosis (TB) a disease that we conquered in the 20th Century? How big of a threat is TB worldwide?

We say that TB is the world’s oldest pandemic. It has existed for as long as we have history, and it remains the world’s second largest killer when it comes to infectious disease. It was the most deadly, but COVID bumped it into the second spot temporarily. This is especially concerning because a TB vaccine has existed for over 100 years.

TB is actually the number one cause of death of people living with HIV. So, in order to achieve EGPAF’s mission of ending AIDS in children, we also have to make sure we’re ending TB in kids.

We have treatments; we have cures; we have prevention. We have everything needed to end TB—but it’s still a huge threat, globally.

The reality is that we’re often still using treatments that were approved in the 1960s. And TB programs—from research to diagnosis to treatment—are tremendously underfunded.

The world needs to catch up and treat this grave danger with the sober respect it deserves.

There is currently work on a new TB vaccine. Why is this important, given that we already have a vaccine?

The current TB vaccine is effective in specific populations. In fact, it is effective at preventing TB in children. But that protection tends to wane—and typically by the time you’re an adult, it has little protection left.

But now is a really exciting time in the TB vaccine pipeline. There are six vaccine candidates in phase three trials, which is great. In the next few years over 80,000 participants are expected to be enrolled in TB vaccine studies. We could very possibly have a new vaccine by the end of this decade.

We’ve all seen the enormous impact of COVID vaccines. Part of why the COVID-19 vaccine developed so quickly is because there were significant investments in that research.

When you make those financial and political investments, you do have outcomes from them.

Another lesson from COVID, though, is that there’s a difference between having a vaccine and having vaccinations occur. It’s really making sure that it gets to the people who need it. It’s great to have a new tool, but then you also need to make sure that you’re able to use that tool effectively.

Beyond the vaccine, why do children pose a challenge when it comes to TB?

What we’ve seen with children is that often the biggest gap with TB services is around case-finding and diagnosis. And, obviously, if you don’t know which children have TB, you can’t treat them.

Historically you diagnosed TB by collecting a sputum sample, waiting for the bacterium to grow, and looking under a microscope. It takes weeks for a bacterium to grow. It is not super precise. It is not user friendly.

And then, specifically, when you look at kids, they often don’t produce sputum when they have TB. If your diagnosis is based on being able to examine a sputum sample, you’re not able to easily do that with a kid.

It is vital to have a child-friendly, comprehensive approach to screening and diagnosis— including rapid, non-sputum-based diagnostic tools, so families aren’t waiting and waiting for a diagnosis. Countries also need to ensure health care workers are trained to identify kids with TB.

Along with expanding the access to child-friendly rapid testing, there have been advances in TB preventive therapy (TPT), which is a potential game-changer.

TPT is a little different than you normally think about when it comes to prevention. It doesn’t prevent you from ever being infected with TB, but it prevents that infection from turning into a full-blown symptomatic disease. It is a tremendous opportunity because why wouldn’t you want to treat someone before they ever have symptoms?

It’s key both for the person who is living with TB, as well as preventing spread.

This makes contact tracing even more important. You can actually prevent TB from affecting everyone in the household by administering preventive therapy if one person tests positive for TB.

What are some ways that we can build a more sustainable response to TB?

Sustainability is a very hot topic at the moment—along with pandemic preparedness. And investments in TB are investments in pandemic preparedness.

When COVID hit, the very first programs called upon to respond were TB services. But much of the infrastructure that supports TB can simultaneously support a variety of diseases. You can build systems that are not siloes.

If you’re investing in lab networks, you can use those labs for a variety of threats. For example, imagine if a patient comes to a clinic with a cough. With a GeneXpert machine, you can test for COVID, switch test cartridges, and then test for TB.

Much of the work done in TB programs creates building blocks to strengthen a health system: contact tracing, adapting the built environment, expanding lab networks. All of these investments are so relevant to any new threat that might emerge and also have hugely beneficial impacts on fighting other epidemics.

So much, though, comes down to funding, once again. TB needs money. That’s the top line message here.

For being the largest infectious disease killer globally, the share of funding that goes towards TB efforts is, actually, extremely small.

And while HIV is largely funded by international sources like the United States and the Global Fund, 80% of TB services are funded domestically—within a country.

The UN high-level meeting that just happened last September set a global goal that by 2027, $22 billion should be invested annually for TB prevention, diagnosis, treatment, and care.

Spoiler alert: we are not close to that goal.

Currently, the USAID TB program budget is $390 million a year—and the United States is the largest bilateral funder for TB globally. In 2022, $5.8 billion was available, globally. So in order to reach these targets in the next three years, we have about a $17 billion funding gap to overcome.

There’s a really dramatic need for resources, both for scaling up existing programs as well as investing in research and development of new tools. TB trials are large. They take time and need money to be effective.

What makes you excited about working on TB right now?

Like I said, TB is in an exciting moment—there are so many research advancements.

TB treatments, traditionally, have been pretty toxic. It has required a high number of pills taken for a long duration—sometimes years. You must take them daily. And the treatments can have really harsh side effects. Some people lose their hearing; some people have jaundice—which, obviously, makes it harder to adhere to treatment and harder to cure.

But similar to some of the innovations we’ve seen in HIV of shortening pill burdens, we’re starting to see that in TB as well. So as opposed to taking pills for a year or two, you’re taking them for four months. Or instead of getting painful injections, you can stick to all-oral treatments.

Until recently, it had been decades since there were new TB treatments, and suddenly, we are in this flurry of shorter treatments. It feels like there’s a bit of an upward spiral where it’s like, “OK, we got this shortened to four months. Can we go to three? Could we go to two?”

It feels like there is momentum that just needs to be harnessed and fueled by financial investments. If you care about ending this health threat, you should contact your congressional members to tell them to fund USAID’s TB program and PEPFAR, as well. With additional tools and with focused political will and finances, we can end it.

I can honestly say, “Yes, we can end TB.”  That really excites me.

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This interview was originally published on LinkedIn.