There is the unknown extent of the deadly new strain of tuberculosis in
Dr Fabio Scano, a TB expert from the World Health Organization in Geneva, has been sent to South Africa at the request of the government to assist with the outbreak of the extensively drug-resistant tuberculosis strain, or XDR-TB.
"We don't know the extent of multiple drug resistant and extreme drug resistant TB in sub-Saharan Africa and the southern African region. There is not yet the capacity to test in these countries," Scano said at a news conference.
South Africa has reported 352 cases of the virulent strain since it was discovered last year in the eastern KwaZulu-Natal province. There have been 221 deaths and concerns have been raised about the strain spreading across the region.
Scano said an epidemiological investigation was under way to determine the full extent of the disease.
"I don't think the situation in KwaZulu-Natal is unique," said Professor Ronnie Green-Thompson, special adviser to the health minister. "If we test in other provinces we may well find a similar prevalence."
Multiple drug resistant TB, known as MDR-TB, does not respond to a "first line" of drugs while the extreme strain does not respond to a "second line" of drugs.
Africa is the only continent where TB rates are increasing and the disease is complicated by high rates of HIV infection, which lowers a person's immune system.
"MDR-TB and XDR-TB and the way they are magnified by HIV infection is the biggest public health challenge both nationally and internationally," Scano said.
He said that without the drug resistant strain, 12-14 percent of TB patients who have HIV die because of the "lethal combination" of the two diseases.
Scano said WHO was committed to working with South Africa to address the challenge presented by the disease.
"There are a lot of interventions under way but we have yet to see the results ... the fight against TB is a marathon, not a sprint. But there is a need for action now," he said.
Drug resistance grows when people do not complete a grueling six month regime of medication, and South Africa has a low adherence rate.
Part of the two-year collaboration between WHO and South Africa is to ensure greater adherence of patients to the treatment programs.
The health department has had to force a number of XDR-TB patients back to hospital after they tried to return to their homes and in the United States, a 27-year-old man suffering from the extreme strain has been locked up indefinitely as a danger to the public.
Nthari Matsau, Deputy Director-General of the health department, stressed that while it was important to separate TB patients, issues of discrimination and human rights had to be considered.
"Incarceration is not an ideal way of separating TB patients. There are much more acceptable and humane ways," she said.
Scano said new drugs to treat XDR-TB were now available in South Africa but he said there was a huge need for new medicines to be developed to combat the disease.
"Unless there is massive investment in new drugs, we won't make headway in the fight against TB. We have to do the best we can with what we have," he said.