Top health stories of 2014

This year, three West African countries found themselves at the center of the biggest public health crisis the world has seen in decades. Since the Ebola outbreak was first reported in March, the deadly disease has swept through Liberia, Sierra Leone and Guinea, killing more than 7,500 people and sickening nearly 20,000.

International aid was slow to mobilize, allowing the epidemic to spiral out of control.

The Ebola Hot Zone

Lara Logan travels to Liberia to report on Americans working on the frontline of the Ebola outbreak.

The virus tore through villages without adequate medical facilities where families cared for the sick at home and then buried the still-infectious bodies of the dead without proper precautions.

Ebola is a hemorrhagic virus that causes flu-like symptoms including fever, intense weakness, muscle pain, headache and sore throat. These are followed by vomiting, diarrhea, rash, impaired kidney and liver function, and sometimes internal and external bleeding. The Ebola virus is transmitted only through direct contact with bodily fluids from a sick patient.

International efforts are underway to develop a vaccine or drug treatment, several of which have shown promise in early testing.

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