Damn. Martin Salia, a surgeon who caught Ebola while working in Sierra Leone and was flown to the US on Saturday for treatment, died this morning. His case was too advanced.

He was given the experimental drug ZMapp on Saturday. He also received a plasma transfusion from an Ebola survivor. That treatment is thought to offer antibodies to fight the virus, said doctors at the hospital. He was flown from Freetown in a heavily equipped air ambulance for treatment in the United States at the Nebraska Medical Center.

But within the first 12 hours he was in complete respiratory failure and had very low blood pressure, doctors said during a news conference.

It was too late.

Martin Salia contracted the virus in Sierra Leone, where he was the chief medical officer and surgeon at the Kissy United Methodist Hospital in the capital of Freetown. He also worked at several other hospitals in Sierra Leone.

After Salia initially tested negative, his colleagues embraced him, celebrating the good news. The hospital has since been shuttered and three of his colleagues are being isolated over Ebola fears. It is still unclear how Salia contracted Ebola, which had killed nearly 5,200 people worldwide as of Nov. 11,according to the World Health Organization.

He had symptoms and got tested, but the test came back negative.

But when his symptoms remained nearly a week later, Salia took another test, on Nov. 10. This one came back positive, sending the Sierra Leonean doctor with ties to Maryland on a desperate, belated quest for treatment and forcing the colleagues who had embraced him into quarantine.

And it was too late.

In a sign that the Ebola epidemic still poses a danger, even though it may have eased in parts of Liberia, the Centers for Disease Control and Prevention announced Sunday that airport screening will begin for travelers arriving in the United States from Mali, which lies inland from Sierra Leone and Liberia and has begun to report cases of the disease.

For Sierra Leone’s medical establishment, already rocked by Ebola, another doctor’s diagnosis was devastating national news. Since the outbreak started, 320 Sierra Leonean health workers have died of the disease. New billboards in Freetown show the faces of doctors who have died, with the words “Some of our national heroes killed by Ebola.”

It’s heartbreaking.

Early tests for Ebola aren’t reliable, we’re told.

The doctors who tended to him in Freetown appeared to be unaware that an early Ebola test — taken within the first three days of the illness — is often inconclusive. In a country where information about the disease continues to move slowly, it was another potentially tragic mistake.

In many cases, a negative test at that stage means nothing because “there aren’t enough copies of the virus in the blood for the test to pick up,” said Ermias Belay, the head of the CDC’s Ebola response team in Sierra Leone.

Now his colleagues could be infected.