An ambulance transports Ashoka Mukpo, a freelance cameraman who contracted Ebola in Liberia, to the Nebraska Medical Center in Omaha, Nebraska, Oct. 6, 2014.
An ambulance transports Ashoka Mukpo, a freelance cameraman who contracted Ebola in Liberia, to the Nebraska Medical Center in Omaha, Nebraska, Oct. 6, 2014.

DALLAS - The head of the U.S. Centers for Disease Control says the fight against Ebola in Africa will be long and hard, but he says there are real signs of progress.

At a media briefing in Atlanta Tuesday, Dr. Thomas Frieden said this includes better training, more understanding of the virus, and safer practices, including during burials for Ebola victims.

Frieden said there are no new cases in Nigeria and the outbreak in the Democratic Republic of Congo is contained. He also said there is a decrease in the number of new cases in parts of Liberia — one of the hardest-hit countries.

The Liberian man diagnosed with Ebola in the southwestern U.S. city of Dallas, Texas is still in critical condition after taking an experimental Ebola drug.

Frieden says none of the 48 people being monitored after direct or indirect contact with Thomas Eric Duncan is sick. Officials have said this is a critical week to see if any of those exposed in Dallas develop signs of the virus that has killed more than 3,400 people since an outbreak in West Africa began in March, out of nearly 7,500 confirmed, probable and suspected cases.

"We need to be prepared in Dallas for what could happen," Dr. David Lakey, the commissioner of the Texas Department of State Health Services, told a news conference on Monday.

Jesse Jackson in Dallas

Prominent civil rights activist Reverend Jesse Jackson met members of Duncan's family on Tuesday and plans to hold a prayer vigil later in the day in front of Texas Health Presbyterian Hospital, where Duncan is being treated in an isolation ward.

Jackson told reporters the hospital initially discharged Duncan because he was poor and did not have insurance. About two days after Duncan left the hospital, he was taken back by ambulance and put into isolation.

The hospital and health officials have said mistakes were made in handling the Ebola diagnosis.

Mukpo Gets Brincidofovir

A Nebraska hospital is using the same experimental drug to treat an Ebola patient airlifted from West Africa to its facilities this week as is being used on Duncan in Dallas, who was the first patient diagnosed with thevirus on U.S. soil.

The Nebraska Medical Center said on Tuesday it is using Brincidofovir on Ashoka Mukpo, a freelance NBC cameraman who contracted Ebola in Liberia. The drug was developed by Chimerix Inc. CMRX.O, which said it has been tested in more than 1,000 patients without raising safety concerns.

"We decided this was currently our best option for treatment," said Phil Smith, medical director of the Nebraska Medical Center's Biocontainment Unit, which consulted with U.S. health and drug officials before making its decision.

Mukpo is experiencing symptoms such as nausea, vomiting and diarrhea, said the medical center, which has treated one other patient airlifted from West Africa.

Spain Infection, International Response

But authorities in Spain are trying to figure out how a nurse in Madrid contracted Ebola after treating two missionaries who were flown from Liberia and Sierra Leone.

This is the first known case of transmission outside of Africa.

The nurse is reported to be in stable condition. Her husband, a health care worker who treated the missionaries, and a man who came from Nigeria, are quarantined.

The European Union announced it is airlifting emergency supplies to handle the Ebola crisis in Guinea, Liberia and Sierra Leone. Also Tuesday, the United Nations budget committee approved $50 million for an emergency Ebola response mission and a special envoy's office through the end of the year.

The Pentagon is spending $750 million over the next six months to battle Ebola in Liberia. Two new mobile medical laboratories were deployed last week and 4,000 U.S. service members are being sent to the region.

The U.S. also is working on more screening procedures for airline passengers both in West Africa and the United States.

Some information for this report comes from AP and AFP.