South African health officials say they have confirmed six new cases of a deadly and extremely drug-resistant strain of tuberculosis.
The officials Wednesday said five of the patients diagnosed with so-called XDR-TB are from Gauteng province, which includes Johannesburg.
A spokesman said three of the patients have been hospitalized, while authorities try to track down the other three.
The find has fueled fears the strain may be spreading. A recent outbreak in South Africa's Kwazulu-Natal province killed at least 55 people.
South African Health Minister Mento Tshabalala-Msimang has requested an urgent meeting with the World Health Organization to deal with the outbreak.
The world health body has warned that XDR-TB is a virulent form of tuberculosis resistant to most, perhaps all of the drugs used to treat it.