“We are extremely concerned,” said Dr. Benoit Kebela Ilunga, secretary general of the Congo Health Ministry. “But we also have experience dealing with this.”  Congo is thought to be the birthplace of the Ebola virus, which is named after a river in the north where one of the first documented outbreaks occurred in 1976, killing nearly 300 people. Congo has had at least three other major outbreaks, including one in Kikwit, a town about 200 miles west of the current disease zone.  The virus strikes fast, and many patients die within days of showing symptoms, which start out as stomachaches and headaches and progress to bloody vomiting and organ failure. In some patients veins burst under the skin, causing a purple rash, and blood streams from the nose and mouth.  Health officials said the strange thing about this outbreak, which began in June, was that very few early victims showed any sign of hemorrhaging. Half the initial victims were children with flulike symptoms and many were surviving, which did not seem to fit the Ebola pattern.  “It was a bit of a puzzling picture at the beginning,” said Scott F. Dowell, the director of the Global Disease Detection Program at the Centers for Disease Control and Prevention in Atlanta, which has been in close contact with Congolese officials for several weeks.  But once health workers started dying, Dr. Dowell said, it began to look like Ebola, which is often transmitted through contact with corpses, body fluids and contaminated equipment like needles and surgical tubing. He now thinks that the early stages of the Ebola outbreak may have been masked by more common germs like shigella, a waterborne bacterium that causes severe dysentery.  That is consistent with findings from the W.H.O., which reported that some Congo patients were responding well to ciprofloxacin, a popular antibiotic.  “Over the next few days and weeks, the cases will be sorted out, and you’ll probably end with a picture that looks like the previous Ebola outbreak,” Dr. Dowell said. “Most of the fatalities will be adults. The children cases will be attributed to other diseases.”  Scientists think the Ebola virus lives in an animal host, possibly a bat. Human outbreaks are thought to start when a person is infected by an animal and then passes the virus to other people. There is no cure.  Dr. Ilunga said that so far 372 people have fallen ill and 166 have died. He said the government was concerned that the disease would spread, adding that the first order of business was getting villagers to take sick people to quarantine centers. Congo’s infrastructure woes might actually help. The country is the size of Western Europe but has less than 300 miles of paved roads. Although that makes it harder to get medical supplies and doctors in, health officials said the isolation of central Congo’s towns also means that terminally ill people cannot easily travel far, which can limit the infection’s spread.  Denise Grady contributed reporting from New York.  A version of this article appears in print on , on Page A13 of the New York edition with the headline: A Fatal Outbreak in Congo Is Ascribed Partly to Ebola. Order Reprints| Today's Paper|Subscribe
The lethal Ebola virus has resurfaced in central Congo, U.N.  officials said, and health experts were rushing supplies and doctors into the remote area to contain the disease.