By Thomas Frieden
As the world's worst Ebola epidemic fades in the rearview mirror of history, it's worth remembering what happened and the key lessons learned. Beginning in March 2014, Ebola began spreading rapidly in Sierra Leone, Liberia, and Guinea. Nearly 30,000 people were eventually afflicted with the disease, and more than 11,000 died. Ebola spread to Nigeria, Mali, the United States, and other countries.
In response to the emerging epidemic, the Centers for Disease Control and Prevention activated its Emergency Operations Center to fight Ebola. This would become the CDC's largest and most intense outbreak response in its 70-year history.
The situation was ominous: Ebola was exploding in West Africa, threatening to ignite a global catastrophe. In the following months, more than 4,000 CDC doctors, nurses, laboratory scientists, disease control experts, and others were involved in the response. Nearly half traveled overseas, or to airports, quarantine stations, and hospitals within the United States.
For example, laboratory experts set up a mobile lab in Sierra Leone, relocated it as the epidemic shifted, and conducted high-quality, high-throughput testing on more than 27,000 specimens from all over that country for 421 days without interruption. Details of the agency's comprehensive response are documented in a new supplement to the Morbidity and Mortality Weekly Report.
Staff not directly involved in the response doubled down on their duties to ensure the health of the American public during the massive Ebola effort. It's a good thing they did. Even as the last embers of the Ebola wildfire still burned, CDC needed to launch a new, full-scale emergency response, this time to fight the Zika outbreak in the Americas. Many of the same disease detectives, lab workers, health communicators, and other staff still working on Ebola turned without pause to begin fighting Zika.
There are big differences between the two diseases. Ebola spreads rapidly through a population by direct contact with the blood or body fluids of a person who is sick with or has died from Ebola. It causes highly identifiable symptoms, and is often deadly. Zika is a different kind of health threat. It's a silent epidemic because most people infected with the Zika virus have mild symptoms, or none at all. It's only months after it infects pregnant women -- when pregnancies are lost or babies are born with severe birth defects -- that the devastating impact of the virus becomes apparent.
There's also a big difference between our country's responses to the two diseases. Quick action taken by Congress to provide desperately needed funding and other resources was critical to CDC's ability to stop Ebola and build safeguards needed to prevent an Ebola resurgence. Yet no such action has yet been taken on Zika, despite the dire threat the virus poses to pregnant women and their developing fetuses.
Even with swift congressional funding, Ebola took its toll. In addition to directly claiming thousands of lives, the epidemic devastated fragile health systems. Many more people died because of Ebola than from Ebola. Thousands died unnecessarily from malaria, tuberculosis, and other diseases because the epidemic shuttered clinics and hospitals and derailed programs to deliver vaccines and prevent and treat non-Ebola diseases.
Ebola showed us how important it is to make sure that our nation and others have the capacity to rapidly detect, respond to, and prevent disease outbreaks. Yet CDC has had to borrow resources from its ongoing, vital work on Ebola to launch and sustain our fight against Zika. The funds we've borrowed from are essential to find and stop Ebola as embers of the epidemic continue to smolder in West Africa, to respond to new cases and clusters of Ebola, and to build each country's capacity to detect and respond to health threats. We must learn from the past to protect Americans now and in the future.
Ebola tested the world's readiness to respond to global health emergencies. It reminded us that a threat to health anywhere can be a threat to health everywhere. We must now wage an efficient and effective fight against Zika while continuing to strengthen early-warning and rapid-response systems around the world and continuously improve preparedness for the inevitable future emerging disease outbreaks we will face. CDC is using borrowed money on borrowed time to support a comprehensive Zika response while keeping a watchful eye on Ebola and other health threats. The stakes are too high not to fully commit to protecting America's health.
Thomas R. Frieden, MD, is the director of the Centers for Disease Control and Prevention.