“Today we can use molecular research to understand transmission of infectious diseases geographically in ways not possible before,” said Sir Mark Walport, a rheumatologist/immunologist. Director of the Wellcome Trust, one of the largest medical research charity foundations in the world, he will soon begin his post as chief scientific adviser to the U.K. government. He delivered the annual David Barmes Global Health Lecture, titled, “From John Snow to Genome Science,” in Masur Auditorium recently.
While environmental factors such as temperature or rainfall can determine geographic distribution of disease, so can such challenges as poor infrastructure and unsafe drinking water.
“In this country, we expect the water we drink will have been effectively separated from the water that we excrete,” said Walport. “Sadly, that is not true in many parts of the world.”
It certainly wasn’t so in mid-1800s London, where cholera outbreaks were claiming thousands of lives. At the time, a British anesthesiologist named John Snow, considered the father of epidemiology, believed polluted water was the culprit. Through careful clinical observation, Snow determined many cases of cholera were clustered around a water pump. When he had the pump’s handle removed, the outbreak stopped. It was indeed sewage-contaminated water causing the infections.
“Science is all about using the right tool for the right question,” said Walport. One apparatus, the Bangkok bed—simply a bed with a hole in it and a bucket underneath—has been important in the history and management of cholera. It helps measure lost fluid so doctors can create replacement therapy from rehydration fluids to antibiotics.
Cholera remains a global health threat today, with 3 million to 5 million cases worldwide and more than 100,000 deaths annually, said Walport. Little was known about cholera in Snow’s day. But today we can map its global transmission.
In an age of great mobility fueled by high-speed travel, Walport underscored understanding how infectious diseases move around the world, among individuals and populations. Southeast Asia has been a hotbed for cholera outbreaks since the early 19th century. In 2010, when UN troops from Nepal arrived in Haiti following the earthquake, cholera appeared there for the first time in a century. The disease was transmitted through contaminated water that travelled from the UN camp down the river; within a few months, more than 300,000 Haitians were infected and thousands died.
Following a recent outbreak of MRSA (antibiotic-resistant staph) in a British hospital, repeated deep cleanings in the ward did not prevent additional outbreaks. A staff carrier was soon identified and then infections stopped. Sequencing analysis identified a novel, more pathogenic organism. Understanding the genotype, said Walport, allows us to learn more about the evolution of infection and can lead to new treatments.
Clinical researchers should seize new opportunities in science, said Walport, who underscored accurate phenotyping, genotyping and utilizing medical imaging and informatics.
“This, I think, is the start of the future of microbiology…We’ll be able to use sequencing information to identify organisms in ways that weren’t possible before,” said Walport. “That sequencing will tell us more about the pathogenicity because we’ll be able to identify virulence factors, antibiotic resistance as it evolves and, importantly, we’re going to be able to investigate transmission of infections both at a global scale and at a local scale in ways that will actually alter clinical management.”
A major challenge Walport cited is building capacity in the developing world to support scientists and assure adequate facilities for conducting research. Developing countries are plagued with poor infrastructure, poverty, poor education, malnutrition and bad policies, all challenges to improving their health systems. Diseases of inequality, such as childhood diarrhea, run rampant.
The Wellcome Trust supports capacity-building initiatives. Major malaria research programs are under way in Malawi, Kenya, South Africa and Southeast Asia. Walport said research on the drug artemisinin, used to treat severe malaria cases, has now become the global recommendation. But since drug resistance is emerging in Southeast Asia, it’s important to find new treatments. Another global concern, and a lethal one, he said, is the counterfeiting of anti-malarial drugs.
“I think it’s worth emphasizing that funding global health research is a collaborative activity,” said Walport, who highlighted the need for public-private efforts. The Wellcome Trust’s newest partnership with NIH is H3Africa, which seeks to understand disease susceptibility and drug responses in African populations.
“The fascination of genomics is how much it tells us about our own interrelationships, one to another, about family history and the very close relationships of human populations,” said Walport. By bolstering research, fostering collaborations and improving access for all to innovations, technology and medicine, Walport said, we can move from global health to global sustainability.
On hand for Walport’s (third from r) talk were (from l) NCI director Dr. Harold Varmus, NIAID director Dr. Anthony Fauci, NIH director Dr. Francis Collins, NIDCR director Dr. Martha Somerman and FIC director Dr. Roger Glass. The Barmes Lecture was presented by Fogarty International Center and NIDCR.
Photos: Ernie Branson