Better strategies to track every individual exposed to the Ebola virus was what finally brought the epidemic in Sierra Leone under control, according to Laura K. Lester, DVM DACVPM, a Major with the US Army Veterinary Corps, who this month will conclude a two-year CDC fellowship with the Arkansas Department of Health (ADH).
Last October, the CDC called Dr. Lester away from her post at the ADH as an Epidemic Intelligence Service Officer working with the state epidemiologist to provide surveillance and advisory support in the small country on the West Africa coast.
At a special presentation at UAMS on June 4 hosted by the COPH Department of Epidemiology, she talked about the month she spent there last fall, along with hundreds of other public health workers from nearly every continent. She was sent to Kenema District, 180 miles inland from the capital city of Freetown on the coast, which had experienced the worst of the outbreak two months previously.
At the peak of the epidemic, more than 600 cases were reported in Sierra Leone each week.
The epidemic had caught the country, one of the poorest in the world, “completely off guard,” she recalled. “There were a lot of issues, confusion, and chaos, and we were there to help try to pull it together. The country needed all hands on deck.”
The disease had simmered for months in the forests, where traditional healers attempted to cure it, many dying themselves. It is believed to have started in December 2013 with human contact with an animal host. By March 2014, the CDC declared it an epidemic. It would become the largest international outbreak response by the CDC in its 70-year history.
Data management for field surveillance, critical to stopping the spread of Ebola, was Dr. Lester’s main objective when she arrived. Each potentially exposed person had to be identified, quarantined for 21 days and report all others they might have infected. At first, only six contacts on average were identified for each exposure.
Ebola is not as highly contagious as other diseases but there is no cure, and the fatality rate is high without proper care. In one year, of the nearly 13,000 confirmed cases in Sierra Leone, 30 percent died.
Lack of knowledge about how it spreads, lack of trust of the government and lack of cooperation with tribal leaders initially hampered public health efforts. People hid in forests or fled across porous borders out of stigma or fear. Precautions for avoiding contamination from an infected body conflicted with traditional ceremonial burial rites.
“Villagers would chase the surveillance team out with rocks,” Dr. Lester said. There were rumors that the World Health Organization was spreading Ebola through the exhaust of the agency’s vehicles.
Gradually, awareness and trust grew with efforts to educate and engage communities, one household at a time. Culturally appropriate signage, pictograms and the pop music “Ebola reggae” on the radio helped dispel rumors that the disease was a political hoax and gave advice about how to prevent its spread.
A turning point was when members of a chieftain’s household became ill with Ebola; after that, he was an ally.
In time, the number of contacts per exposure rose to almost 20. The success rate for contact tracing for 55,000 suspect reports and over 96,000 contacts in one year in Sierra Leone rose to 97 percent by this May.
Ebola remains a threat in Sierra Leone, but under 20 new cases are reported weekly. This link has more information about the epidemic and the CDC’s response to it.