As of Friday, eight confirmed cases of Ebola have been or are being treated in the United States, and one U.S. citizen died abroad, having never returned to the States. Dozens of others are being monitored or are in some form of quarantine.

Here is a breakdown of U.S. Ebola cases and precautions as of October 17 (Cases in which full Ebola tests were conducted and found negative -- or in which Ebola was ruled out at the outset -- are not included on this list):

8 confirmed cases of Ebola in the United States

Dr. Kent Brantly (missionary) -- Discharged from Emory University Hospital in Atlanta on August 21.

JUST WATCHED Lab worker quarantined on cruise ship Replay More Videos ... MUST WATCH Lab worker quarantined on cruise ship 01:54

JUST WATCHED Texas Ebola nurse 'amazingly upbeat' Replay More Videos ... MUST WATCH Texas Ebola nurse 'amazingly upbeat' 02:10

Nancy Writebol (missionary) -- Discharged from Emory University Hospital on August 19.

Thomas Eric Duncan (Liberian) -- Died October 8; was treated for Ebola at Texas Health Presbyterian Hospital Dallas.

Amber Vinson (nurse at Texas Health Presbyterian) -- Currently receiving treatment at Emory University Hospital after being transported from Dallas on October 15.

Nina Pham (nurse at Texas Health Presbyterian) -- Currently receiving treatment; transferred to a NIH hospital in Maryland, from Dallas, for treatment on October 16.

Dr. Rick Sacra (missionary) -- Discharged from the Nebraska Medical Center on September 25; was admitted to a hospital in Worcester, Massachusetts, for a respiratory virus on October 4; and was released the following day.

Ashoka Mukpo (NBC News freelancer) -- Currently receiving treatment at Nebraska Medical Center; diagnosed in Liberia on October 2.

Name unknown -- Currently receiving treatment at Emory University Hospital; the World Health Organization and Emory are not confirming that the patient worked for WHO; arrived at Emory on September 9.

1 confirmed case, U.S. citizen abroad:

Patrick Sawyer, a government official in the Liberian Ministry of Finance and a naturalized U.S. citizen from Minnesota, died July 25 in Nigeria after caring for his Ebola-stricken sister in Liberia.

Monitoring

-- At least 76 health care workers who may have come into contact with Thomas Eric Duncan after he was hospitalized are being monitored for symptoms of the disease, the CDC said. The CDC is considering putting 76 health care workers at Texas Health Presbyterian Hospital Dallas on its "Do Not Board" list.

-- Those being monitored in Texas for possible Ebola exposure include Dallas County's top public health epidemiologist, Dr. Wendy Chung, according to Dallas County Judge Clay Jenkins.

-- Jenkins said 48 other people in the community are still being monitored after having contact with Duncan. All were asymptomatic as of October 16. They might not have to self-monitor for much longer. Duncan was admitted to Texas Health Presbyterian on September 28, and the 21-day monitoring period will end October 19 for those who had contact with him outside the hospital.

-- But others may be monitored in Texas because they had contact with the two nurses who treated Duncan and now have Ebola. Amber Vinson, for example, began showing symptoms on October 14 -- which would mean the 21-day monitoring period for her contacts ends on November 4.

-- Health officials are monitoring 16 people in northeast Ohio after being in the vicinity of or having contact with Amber Vinson, including Vinson's stepfather, Kelvin Berry. Of those 16, 12 are in Summit County, and four are in Cuyahoga County. One of the 16 was a "close contact" and is under quarantine. Some of the 16, including two employees at the bridal store where Vinson visited, are on self-quarantine; at this point the 21-day quarantine does not apply to them.

-- Eight people on Amber Vinson's October 13 flight from Cleveland to Dallas are being actively monitored in Texas, with health professionals visiting them periodically to record their temperatures, Gov. Rick Perry said on October 17. Health professionals are staying in contact with 71 other passengers on that Cleveland-to-Dallas flight by phone, Perry said.

Notification s

-- The CDC is asking all passengers on Amber Vinson's flights between Cleveland and Dallas, including passengers on Flight 1142 from Dallas to Cleveland on October 10, and 132 passengers on Flight 1143 from Cleveland to Dallas on October 13, to contact them. Anyone determined to be at any potential risk will be monitored. The six crew members on Flight 1143 have been placed on paid leave for 21 days by the airline. Frontier Airlines also is notifying up to 800 people -- those who were aboard those flights, as well as five other trips taken by the plane before the airline temporarily took it out of service -- to contact the CDC or state health officials if they have any concerns.

JUST WATCHED Passenger on quarantine: We weren't aware Replay More Videos ... MUST WATCH Passenger on quarantine: We weren't aware 02:48

JUST WATCHED Passengers sat 3 feet from Ebola patient Replay More Videos ... MUST WATCH Passengers sat 3 feet from Ebola patient 02:08

JUST WATCHED UK medical ship joining Ebola efforts Replay More Videos ... MUST WATCH UK medical ship joining Ebola efforts 02:33

Quarantines

Belize -- A Texas hospital health worker who may have handled Thomas Eric Duncan's fluid samples has been quarantined on a cruise ship, the U.S. State Department said Friday. A doctor at the cruise ship has declared the worker symptom-free and in good health.

Northeast Ohio -- One of the 16 monitored contacts of Amber Vinson was a "close contact" and is under quarantine, according to Dr. Mary DiOrio of the Ohio Department of Health.

Dallas -- Amber Vinson's mother, Debra Berry, is under self-quarantine at a Dallas hotel. Two unnamed staff members at Windsor Senior Living in Dallas were quarantined on October 6 after coming in contact with Thomas Eric Duncan, according to the facility's managers, and will remain quarantined until October 27.

Unconfirmed cases

New Haven, Connecticut -- A Yale University doctoral student is currently in isolation at Yale-New Haven Hospital, though preliminary tests have come back negative, CNN affiliate WTNH reported. The student recently returned from a trip to Liberia.