WINNIPEG - Scientists may never know the true extent of the Ebola outbreak that drew an international response to a remote region of the Democratic Republic of Congo, a Canadian expert said Monday.
"I don't want to be too pessimistic, but I'm afraid we will never find out the real numbers of this outbreak because of the huge logistic issues in that country,'' said Dr. Heinz Feldmann, head of the special pathogens division on the National Microbiology Laboratory in Winnipeg.
Feldmann and two colleagues spent close to three weeks in the African country, armed with a small mobile lab that allows blood tests to be carried out even in areas without electricity and other modern conveniences.
They were spelled off earlier this month by a second team from the Winnipeg lab, who were preparing to start the long journey home Tuesday.
Since there have been no new cases of Ebola in the last 21 days -- the disease's incubation period -- officials believe the outbreak is well under control.
The international response was prompted by reports that hundreds of people had contracted Ebola Zaire, a strain that usually kills between 80 and 90 per cent of infected persons.
Scientists, however, have only confirmed 25 cases through lab tests.
There is no way to confirm infections in the people who died before international teams arrived in September. Another complicating factor is the fact that people with typhoid fever and other diseases can exhibit the same symptoms as Ebola victims and be misdiagnosed.
The virus is spread through direct contact with infected blood or through sexual contact with an infected person. There is no medicine, treatment or cure for the virus.
Ebola is characterized by a high fever, intense weakness, muscle pain and a sore throat. It progresses quickly, usually causing vomiting, diarrhea, and impaired liver and kidney functions.
"The people that are involved in this outbreak have been very happy to have us, because of the fact we have such quick turnaround time with the lab,'' Dr. Jim Strong, a member of the second Canadian team, said via telephone from the DRC.
The cause of the outbreak also remains a mystery. Some previous outbreaks have been linked to the consumption of so-called ''bush meat'' -- a range of animals that includes primates.
"There is no real indication that great apes have been involved,'' said Feldmann.
"Bush meat will always be involved to some extent, but we don't know what the source of the infection was -- whether it was bush meat that was butchered and eaten ... or whether it was bats that are considered a potential reservoir species.''
