Zika Outbreak Timeline: How Our Understanding of the Disease Has Changed

Our understanding of Zika has changed significantly in recent months.

— -- The Zika virus was first identified in 1947 and did not receive much attention from scientists until last year's outbreak in Brazil.

Massive amounts of resources have now been dedicated to understanding and stopping the virus that has been linked to the birth defect microcephaly.

Here's a rundown at the major events of the Zika outbreak.

1947:

May 2015:

October-November 2015:

November 11, 2015:

November 17, 2015:

December 2015:

December 31, 2015:

January 2016:

January 12, 2016:

January 15, 2016:

February 2, 2016:

February 4, 2016:

April 13, 2016:

“It is now clear that the virus causes microcephaly,” CDC Director Tom Frieden said. “We’ve now confirmed what mounting evidence has suggested, affirming our early guidance to pregnant women and their partners to take steps to avoid Zika infection and to health care professionals who are talking to patients every day. We are working to do everything possible to protect the American public.”

April 15, 2016:

May 2016:

July 15, 2016:

July 26, 2016:

July 29, 2016:

"This is not just a Florida issue. This is a U.S. issue. It is a national issue. We’re just the front of it," Scott said during a news conference.

August 1, 2016:

Dr. Shakira Sanchez-Collins is an Internal Medicine/Urban Health Resident at Johns Hopkins Hospital who is currently working at ABC News in the medical unit.