Knowledge gained during West Africa’s outbreak, from persistence of infections to a vaccine’s potential and needs to integrate research are informing responses
A little more than a month after the first time Liberia was declared free of the Ebola outbreak that had devastated communities from its most remote reaches to its capital, an oral swab confirmed the virus had somehow surfaced again and killed a 17-year-old boy. Further investigation found the particular strain of virus originated from a transmission chain that had stopped nearly a year earlier. By the time the investigation, and the “flare-up” of transmissions had ended, a total of seven people were confirmed to have been infected.
The flare-up was one of eight over the year that followed in areas where the outbreak had appeared to be ended, as described in a report released in The Journal of Infectious Diseases. It was also one of a series of events that changed responses to a long-neglected disease, currently being countered — with varying success controlled, and, now, researched — in a war zone.
On the day the World Health Organization announced the start of a first multicountry, multi-outbreak clinical trial of Ebola therapies, the report was among a series released by The Journal of Infectious Diseases taking stock of advances against the virus, as well as against Marburg virus, that have gathered force in the last half decade, in a special edition marking 50 years since the latter disease was first recognized.
Most of those 50 years were marked by lags — in time and investment — to counter outbreaks that, with limited range, struck places with limited resources, the preface to the edition notes. That changed first in the mid-1990s, with recognition that the viruses could be weaponized, and finally, it is hoped, with recognition of the humanitarian and public health disaster brought by the spread of Ebola in three West African countries from 2013 to 2016. Now, the authors of the preface note, following years of neglect, “a vibrant research community” continues to face enormous gaps in tools, skills and capacities stemming from a long lack of investment. And, as articles throughout the edition, individually and taken together show, the stakes in continued momentum are only increasing and becoming clearer.
If the ground gained across three countries by the West Africa outbreak during the initial months of indifference and neglect provided the most obvious lesson of that crisis, the 13 months between the first declaration that the outbreak had ended in one of the countries, and the final declaration that it was really over provided the most daunting lesson. By the time the outbreak had ended, at least 8 flare-ups had interrupted the optimism of three of four declarations transmission had ended in Liberia, and one of the two in Guinea.
Ebola Virus Transmission Caused by Persistently Infected Survivors of the 2014-2016 Outbreak in West Africa highlights the eight flare-ups of transmission that introduced new challenges to Ebola responses. They included an Ebola-infected Liberian woman with no link to chains of ongoing transmission, whose only exposure had been through sex with a man who had recovered from the virus five months earlier. Also included was a 9-month-old baby who died of Ebola, whose parents’ blood and urine tested negative for the virus, while the mother’s breast milk and father’s semen tested positive — both, apparently undiagnosed survivors, the authors of the report write. Taken together, the knowledge gained about transmittable viral persistence — in semen for as long as 18 months — point to needs for monitoring, counseling, condom use, and, now, vaccinations for all contacts of Ebola patients prior to patients’ release from treatment — possible now because of tools developed during that outbreak.
The edition, a special supplement to the Journal, includes coverage of advances in epidemiology, diagnosis, treatment and prevention, including a look at how research toward effective treatment can, and must continue even in the midst of responses, with The Past Need Not Be Prologue: Recommendations for Testing and Positioning the Most-Promising Medical Countermeasures for the Next Outbreak of Ebola Virus Infection.