BlogBy Pardis Sabeti
Abuja — This year's outbreak of the Ebola virus disease in Guinea has killed 147 people, and counting. In 2013, Ebola and Marburg viruses re-emerged in the Democratic Republic of Congo and Uganda. In 2012, it was Lassa fever: the Nigerian Federal Ministry of Health declared an epidemic, with cases reported in 23 of the country's 36 states. While these diseases understandably cause alarm, there is also some reassurance to be found in the way affected countries are becoming better equipped to diagnose and deal with these threats.
These so-called "emerging" diseases may in fact be both much older and much more common than previously thought. Through our experiences in Sierra Leone and Nigeria, my colleagues and I have come to believe that diseases like Ebola and Lassa - first discovered in the second half of the 20th century - may in fact have been circulating in villages for centuries.
In reality, these diseases may only be rare in their detection. Despite popular accounts, viral hemorrhagic fevers often have general symptoms, such as fever and headache, which can be mistaken for malaria or typhoid. Beyond misdiagnosis, many individuals with fever never come to the hospital at all despite having serious and sometimes fatal infections.
Indeed, these diseases may only be new to Western medicine. Lassa virus was discovered when two missionary nurses succumbed to the disease while working in Nigeria. Marburg virus was discovered in the town of the same name in Germany when workers at a primate centre began suffering from fevers, vomiting and bleeding. The Ebola virus was discovered during simultaneous outbreaks at a mission hospital in the Democratic Republic of the Congo and a cotton factory in Sudan.
Understanding these viruses is best done from the field, from places like the Irrua Specialist Teaching Hospital (ISTH) in Nigeria, where I came to work in 2008. My colleagues and I began our research on the genetics of Lassa fever, working with the outstanding local clinicians and scientists. While there, my research partner Christian Happi told me a story of a young boy who was brought to the hospital by his father and successfully treated for Lassa fever. Weeks later Christian had travelled to the boy's village to investigate the origins of his disease. There he learned that the boy's mother had died of the same mysterious disease, as had his cousin and his neighbour. All told, over 20 individuals had died, unnoticed by the outside world. Remarkably, none had come to the hospital, as the hospital had previously had no diagnostic tests for the disease, and limited ability to treat it. Their story made us consider the countless individuals who die silently each year from this disease.
Today, with diagnostic tests able to detect the Lassa virus genome in patient blood and therapeutics on site, the hospital has become a regional centre for treating Lassa fever. Surrounding communities - hearing of the many successful stories like the young boy's - know where to turn, and the site has become a referral centre for patients with undiagnosed febrile illness within hundreds of kilometres. The site is not just a specialist centre for Lassa fever care and research, but also a sentinel site for emerging infectious diseases of all kinds.
Technological advances in analysing the genomes of a wide variety of microbes have the potential to transform the clinical care, surveillance and understanding of devastating diseases like Lassa and Ebola. But to truly fulfil that promise, the tools must be delivered to researchers on the ground - tools for global surveillance and tools for effective diagnosis and treatment of patients where they are.
Happily, strong partnerships between communities and clinics are growing, creating positive feedback loops that save lives and help clinicians to rapidly detect emerging pathogens. There will soon be an African Center of Excellence for Genomics of Infectious Disease (ACEGID) at Redeemer's University in Nigeria, thanks to support from the H3 (Human Heredity and Health) Africa initiative and the World Bank.
The recent Ebola virus outbreak in West Africa highlights the importance of local research centres. In the wake of the incident, members of my team immediately flew to the Kenema Government Hospital in Sierra Leone. While they brought badly needed supplies to help safely diagnose Ebola, they weren't there to take over. They were there simply to support the growing efforts already underway.
Clinicians, nurses, and the public health team at the Kenema hospital have been combatting Lassa fever in Sierra Leone since before the civil war in the 1990s. These outstanding African scientists immediately took control of the situation. Increasingly, sites throughout Africa will have their own diagnostic capacity on site for a wide range of infectious agents. There they will lead on the frontline of the battle against infection disease, supporting their communities and helping to detect, monitor and characterize emerging diseases before they become global threats.
You can learn more about these ideas through this video created by Stephen Gire: "Emerging Disease or Emerging Diagnosis?":
Author: Pardis Sabeti is an Associate Professor at the Center for Systems Biology at Harvard University and a World Economic Forum Young Global Leader. She is participating in the World Economic Forum on Africa 2014 in Abuja, Nigeria.