Convergence: The Future of Health
March 24, 2016
Thank you, Rafael (Dr. Reif), for that kind introduction. It’s great to be here today. I was excited when I got the invitation because the theme of convergence is very much on my mind these days.
In fact, you could say it’s the only way anything of significance gets done in global health – which is our foundation’s primary focus outside of education here in the U.S.
To tackle the really big things – like eradicating polio, taming infectious diseases, and reducing newborn mortality – you often have to involve different fields of scientific study – the natural sciences, the social sciences, the applied sciences, and the formal sciences.
And you also have to bring together different sectors of society like government, academia, philanthropy, the private sector, and civil society.
What I’m excited about, is how we can build on that convergence – that coming together of diverse fields, knowledge, and skills – to zero in on specific strategies and solutions that save lives and improve the health and well-being of millions of people in the poorest countries.
Here’s why . . .
Even though the world has made great progress in recent years, nearly 6 million children under the age of 5 died in 2015.
Most of these children died simply because they happened to be born into poverty – into a community where infectious disease is prevalent, health care is limited, and nutrition is often poor. Most would be alive today if they were born in Washington D.C., or in San Francisco, or any city in Western Europe.
The under-five mortality rate is important because it is the single best measure of child health – which in turn is a barometer of the ability of poor countries to lift themselves out of poverty.
If you look at a pie chart of the causes of under-five child deaths, about 45 percent are classified as neonatal. When I first saw this, I thought: Neonatal isn’t a cause of death! It’s a timeframe – an adjective to describe babies in their first 28 days of life.
But it’s also a very real statistic, especially to people in communities where newborn mortality is high.
I recently visited an area of rural southern Ethiopia where many parents wait a month or more after the birth of a newborn to name their babies. They delay because they are afraid their child will die. And they feel that the death will be a little more bearable if the child is unnamed.
How can it be that in this day and age, 2.6 million babies die before they are even a month old? That’s equivalent to the entire population of Manhattan and two-thirds of the people living in the Bronx. Every year – 2.6 million newborn deaths.
Why are they dying? The shocking truth is, in many cases we simply don’t know.
Precision public health/breast cancer
Today, I want to talk about an approach to public health that will not only answer that question and help more babies survive – but is already beginning to transform the way we think about global health entirely.
It’s a concept called precision public health.
The “precision” will be very familiar to this audience. You know about precision medicine – interventions tailored to specific characteristics of individuals or specific types of disease.
My own affinity for precision medicine comes from a very special place – my medical training as a cancer doctor. I got into it because I wanted to make people feel better.
As a doctor, I didn’t like making people feel bad – even on the path to making them well. But at the time, on the front line in the war on cancer, we had few tools. And the tools we did have didn’t differentiate between the cancer cells we wanted to hit hard and the cells we wanted to preserve.
Then I started working in biotechnology, at Genentech.
You have heard of this drug: Herceptin.
What was new about Herceptin was it allowed us to target the scariest form of breast cancer, HER2 +, with precision. And the precision meant we reduced the side effects.
It was like a miracle. And in a sense, it was. Precision medicine has revolutionized cancer therapy. Everything changed. And now I want everything to change again.
When I joined the Gates Foundation nearly two years ago, I began to think about how we might use this precision technique that harnesses all our best tools - big data, consumer monitoring, gene sequencing, and more – to treat all kinds of diseases.
Why should this major advance, this much smarter way of thinking about treating diseases be limited to the rich world?
I’m not talking about taking expensive drugs like Herceptin and using them to treat women in the developing world.
What I am talking about is taking the same precision approach we have for individuals and applying that to public health issues affecting populations.
In fact, we are already doing it in a limited way – and it’s having a big impact.
Like many doctors who trained in San Francisco in the 1980s, I also trained as an AIDS doctor. It was a terrible time. AIDS was a certain death sentence. All patients died.
Today, with antiretrovirals, things are better. But AIDS is still a big global challenge.
Worldwide about 17 million women are living with HIV.
We know that if women with AIDS get pregnant, they can pass the virus to the baby. And we know that half those babies will die before their second birthday.
We also know that anti-retroviral therapy almost guarantees that mothers won’t pass on the virus.
So what do we do? A “one-size-fits-all” approach – a kind of blast of chemo – might be to say let’s test every pregnant woman for HIV and then treat those who test positive. That would certainly do the job. But in a resource-limited world, it’s just not practical.
So what do we do? We target testing where it’s most needed—where HIV rates are highest. And since we know that HIV is most prevalent in parts of sub-Saharan Africa we can specifically target tests and treatment there.
This precision approach to a public health problem has cut HIV transmission to babies by almost half in five years. Almost half in only five years.
Screening pregnant women in certain developing countries for HIV is a powerful example of using precision to solve a public health problem on a big scale.
And here’s why it works. It works because we know . . . who to target . . . what to target . . . where to target it . . . and how to target it.
That’s how I think about precision public health. Knowing who, what, where, and how.
And that is our problem with those 2.6 million babies who are dying even year.
In many cases we just don’t know. It seems unbelievable. But you know what our best source of knowledge is in the parts of the world with the highest child mortality rates?
It is a conversation with the mother.
A health worker asks a mom who’s just lost her child: “Was your baby running a fever? Were they vomiting?” This discussion might take place up to three months after the baby’s death.
Put yourself in the shoes of that mom. It’s an excruciating, heart-breaking conversation. And it doesn’t do much good, because it’s a very imprecise way to find a cause of death.
Even if mom does remember something, it doesn't really tell you what caused the vomiting, or what caused the fever. So historically there’s been little we could do to prevent that mom, that family, and other families in the same community, from suffering the same tragedy.
We are effectively flying blind. What we need is better data - both for individuals and populations. We need to gather comprehensive, standardized information - including genetic, infectious, environmental, and social factors - to help us understand why children die.
Our foundation is working with our partners to do just that at a number of sites in Africa and South Asia over the next several years, where dedicated individuals using state of the art diagnostic testing will painstakingly collect and log information on childhood deaths.
When these data are analyzed, we will be able to identify patterns and trends - swapping guesswork for scientific evidence. Then we will be able to say, “These are the most common causes of death in babies in this community.” And we’ll be able to start utilizing appropriate remedies or discovering new ones.
For example, we might find that babies in a certain part of Africa are dying from a bacterial infection, passed from the mother, known as Group B Streptococcus.
Untreated, a mother faces a seven-fold increase risk that her next baby will die. But once we know the problem we can solve it with something as cheap, safe, and available as penicillin.
And not every problem will require delivering or developing medicines either. It may be that a population has many babies dying from diarrhea and pneumonia, which we can guard against by promoting an intervention as straightforward as breastfeeding.
We now know more than ever about the remarkable lifesaving benefits of breastfeeding – from nutrition to immunization. If we could make the practice universal, then the results would be startling.
The point is that gaining knowledge about why children in poor countries die will enable us to get the right interventions to the right people in the right places to save lives.
I believe that with these and other improved insights – over the next 15 years a precision public health approach can save 1 million babies every single year. 1 million babies. Every single year.
Other applications of precision public health
And – of course – it doesn’t have to end there. Let’s go back to HIV for a moment. I told you about the gains we are making reducing transmission of HIV from mothers to children. But we know that’s not enough.
Worldwide – every year – 2 million people are newly infected with HIV.
And 1.2 million people die.
Clearly, we need to keep innovating for better solutions. An HIV vaccine is the ultimate goal. But given the likely trajectory of the HIV epidemic, there is an urgent need for new tools to reduce the incidence of infections.
We know that existing prevention interventions, such as condoms, oral PrEP, and behavior change, are not optimal for high-incidence populations.
What we need are a range of long-lasting anti-HIV prophylactic interventions that don’t require active or daily use, that offer choice, and that give women more control.
- A vaginal ring containing a controlled-release anti-HIV prophylactic drug that can be used by young heterosexual women at high risk for HIV infection.
- A long-acting intramuscular injection of a preventative anti-HIV drug that could potentially be delivered by a less skilled health worker.
- And a sub-cutaneous injection of a long-acting preventative anti-HIV antibody that could possibly be self-administered.
When we have these solutions, we can apply the precision approach.
This is what makes precision public health so exciting. It can accelerate progress on a range of global challenges.
In fact, we’re already seeing it being applied to the growing epidemic of Zika virus.
Rapid identification of the apparent link between Zika infection in the first trimester of pregnancy and birth defects has enabled swift scale up of public health information campaigns in areas with the most active transmission.
This includes targeting pregnant women directly . . . and the people they trust – health care providers, teachers, women’s groups . . . even actors in radio soap operas.
It also is enabling public health experts to target vector control efforts and distribution of rapid diagnostic tests to help women identify whether they have been infected with Zika and if they are pregnant.
What’s even more exciting is the prospect that we’ll be able to use precision methods to reduce and eventually eliminate Zika.
Researchers are working on a way to infect disease-carrying Aedes aegypti mosquitoes with an otherwise harmless bacterium called Wolbachia. Once infected, the mosquitos don’t pick up and transmit viruses as easily. And over time, this trait spreads through the mosquito population.
Until recently, this Wolbachia research has focused on reducing the incidence of dengue fever. The same species of mosquito – Aedes aegypti – also carries the Zika virus. So it’s looking very promising that we can use a precision approach to short-circuit the transmission of Zika as well.
Getting there hasn’t been easy and there’s still a lot of work to do. One scientist describe the process of infecting the Aedes aegypti mosquito eggs with Wolbachia this way: “Imagine taking a knitting needle and poking it into a balloon. Then removing the needle without popping the balloon.”
It took thousands of tries over a 10 year period before they were successful.
Scaling up the distribution of hundreds of millions of “friendly Aedes aegypti” in high-risk areas is an even greater challenge. But this is a great example of the potential of precision public health and how it can be applied to emerging epidemics.
Here are a few others ideas to think about.
Imagine if we could pinpoint the specific vitamin and mineral deficiencies in children that cause malnutrition. By community. Based on different diets and different cultural practices. Then we could get the right interventions to those most at risk for the least amount of money and effort.
Or take cervical cancer. Today, it is the most common cancer and leading cause of death among women in developing countries. If we are better informed about the different risks in different populations, we can hone our screening programs and prevention techniques.
The same is true for malaria. Fewer people will contract malaria if we can better track how it spreads among different populations and sub-populations, and how its resistance to our best remedies builds. Because then we can adjust our treatments and work out where each is most effective.
I live in two worlds – one populated by scientists, the other populated by public health professionals. The promise of precision public health is to bring these two worlds together.
But the truth is that we all live in two worlds. There is a rich world and there is a poor world. The exciting thing about precision public health for me is that it brings these two worlds together.
Precision public health adds a layer of equity to precision medicine, taking what we can do for an individual patient and applying it to a population or a community. In other words, it takes the gifts of technology and applies them to the problems of the poor.
Imagine the progress we could make if we take the world’s best minds, best data, and best science – the good stuff like sequencing and molecular biology that is benefiting individuals in the rich world – and use it to get smarter faster so we can select precisely chosen interventions for specific populations, sub-populations, and communities in the developing world.
You know, it’s great to live in a time when we can have a discussion about problems like improving the health of the poor. What’s even better is that we live in a time when we don’t just get to talk about those problems, we actually get a chance to try to solve them.
My dream is to live in a world 10 or 15 years from now where every parent will have the confidence to name their child the moment they are born, dreaming of a future for them that lasts decades, not days.
I look forward to working with all of you to help make that happen. Thank you.