The World Health Organization (WHO) is accusing the government of Tanzania of deliberately withholding information about one confirmed and two suspected cases of Ebola virus disease.

In the most recent report on 14 September, Tanzanian authorities reported they had no cases of the killer virus.  The current Ebola Outbreak has killed more than 2,100 people - mainly in the DR Congo, but also in Uganda.  And both have borders with Tanzania.

The Geneva-based WHO learned that a 34-year-old Tanzanian woman in Dar es Salaam - with a population of more than 4.4 million - fell ill, tested positive for Ebola disease, and died.  She had shown all of the telltale signs of the virus including headache, fever, rash, and bloody diarrhea in early August, and eventually died of hemorrhagic fever on 8 September - but not before visiting several parts of the country and travelling to Uganda.

That's a potentially huge problem, because the only way to curb the spread of Ebola is to carefully trace the movements of infected patients and quarantine anyone they had contacted physically.  Experimental vaccines have been deployed with some success in the DR Congo, but this outbreak has a near-60 percent mortality rate.

WHO is calling on Tanzanian health authorities to come clean with everything it knows:

"Clinical data, results of the investigations, possible contacts and potential laboratory tests performed for differential diagnosis of those patients have not been communicated to WHO," the agency wrote in the statement.  "This information is required for WHO to be able to fully assess of the potential risk posed by this event."

"The limited available official information from Tanzanian authorities represents a challenge for assessing the risk posed by this event," the statement added.