New York, October 24 (RHC)-- New York City has reported its first case of Ebola. Dr. Craig Spencer tested positive after returning last week from Guinea where he was treating Ebola patients with Doctors Without Borders. New York City Mayor Bill de Blasio said Spencer is in isolation at Bellevue Hospital in Manhattan.

De Blasio told reporters: "The patient is now in isolation and the Health Department has a team of disease detectives who have been at work tracing all of the patient’s contacts, and we are prepared to quarantine contacts as necessary."

The West African country of Mali also reported its first case of Ebola on Thursday. The patient is a two-year-old girl who was brought from neighboring Guinea. Her father died of Ebola.

In other news, African countries are pledging to ramp up their response to the Ebola outbreak, which has officially killed nearly 5,000 people in West Africa, although the toll is likely much higher. The African Union said member states have promised to deploy more than 1,600 health workers.