(CNN) -- A patient isolated in a California hospital after possible Ebola exposure does not have the virus, testing revealed.
The unidentified patient, who had recently traveled to West Africa, was isolated at the Kaiser Permanente South Sacramento Medical Center during the testing.
"We're happy to report that we've heard from the Centers for Disease Control that the test result is negative," Dr. Ron Chapman of the California Department of Public Health told reporters Thursday night.
The patient was considered "low-risk," and tests were being conducted out of "an abundance of caution," the public health department said.
The CDC tested the patient's blood samples to determine whether the Ebola virus was present. The hospital said all necessary precautions were being taken to safeguard other patients and staff while the testing was carried out.
There are no confirmed cases of Ebola in the state, the agency said in a statement Wednesday.
On Thursday, Dr. Kent Brantly became the second of two American missionaries infected with the virus when working with Ebola patients in Liberia to be discharged from Emory University Hospital in Atlanta.
The other, Nancy Writebol, was released Tuesday and has decided to not make public comments, according to the hospital.
But Brantly gave a news conference in which he gave thanks for their recovery.
"Today is a miraculous day," Brantly said. "I am thrilled to be alive, to be well and to be reunited with my family."
Emory's staff is confident that the American patients' discharges from hospital pose "no public health threat," said Dr. Bruce Ribner, director of Emory's Infectious Disease Unit.
The pair were the first humans to receive an experimental Ebola drug called ZMapp, which may have saved their lives.
The Ebola virus causes viral hemorrhagic fever, which refers to a group of viruses that affect multiple organ systems in the body and are often accompanied by bleeding.
Early symptoms include sudden onset of fever, weakness, muscle pain, headaches and a sore throat. They later progress to vomiting, diarrhea, impaired kidney and liver function -- and sometimes internal and external bleeding.
The virus spreads through contact with organs and bodily fluids such as blood, saliva, urine and other secretions of infected people.
Earlier this month, a patient with a high fever and gastrointestinal symptoms was admitted to Mount Sinai Hospital in New York City for Ebola testing, but tested negative.
He had recently traveled to a country in West Africa where Ebola has been reported, the hospital said in a statement.
More than 1,350 people have died in the West African Ebola outbreak since the first cases drew attention in March, the WHO said Wednesday. Liberia, Sierra Leone and Guinea have been at the center of the outbreak, with a dozen cases also confirmed in Nigeria.
CNN's Laura Ly and Josh Levs contributed to this report.