BLANTYRE, 18 September 2007 (PlusNews) - When the first cases of extremely drug-resistant tuberculosis (XDR-TB) were reported in South Africa in 2006, the World Health Organisation (WHO) urged other countries in the region to improve their laboratory capacity and implement infection control measures, but Malawi still cannot test for the virtually untreatable TB strain.

Multidrug-resistant TB (MDR-TB) strains cannot be treated by at least two of the main first-line TB drugs, while XDR-TB is resistant to most first and second-line drugs, severely limiting treatment options.

Patients usually develop MDR-TB as a result of not completing treatment for an earlier bout of TB. Failure to complete lengthy MDR-TB treatment creates the risk of developing XDR-TB.

In 2006, at the height of fears that XDR-TB would spread to Malawi, health and population minister Marjolie Ngaunje told the nation that according to surveillance done by the WHO there was no evidence that any extremely resistant strains had reached the country. She added that XDR-TB still posed a threat to Malawi because of its relatively close proximity to South Africa.

Henry Chimbali, a spokesperson for the National TB Control Programme, explained that Malawi could not test for XDR-TB because it lacked the anti XDR-TB drugs needed to test cultures (samples of TB bacteria cultivated in a special liquid). He added, however, that testing of cultures from patients with recurring TB was routine and would alert them to the emergence of drug-resistant strains.

The Central Reference Laboratory in the capital, Lilongwe, which coordinates all TB testing, reported that between 1995 and 2005, there were 71 MDR-TB cases in a total of 95,116 TB patients. Malawi currently has 15 MDR-TB patients undergoing treatment that can take up to two years.

Ngaunje pointed out that Malawi was in a strong position to avoid an XDR-TB outbreak because guidelines for treatment of the disease were being adhered to, with only about four percent of patients failing to complete their six-month course of first-line TB treatment.

Co-infection challenge

While MDR-TB cases remain rare, poverty and a 14.4 percent HIV prevalence have increased the incidence of TB in Malawi to about 27,000 diagnosed cases a year. According to the National TB Control Programme, the disease is now the biggest single cause of adult illness and death, killing about 22 people a day and 8,000 annually. In March 2007, the Malawian government declared TB a national emergency and a number of strategies were put in place.

"Health workers are on high alert to pick up all suspected TB patients at the earliest time possible. Community awareness campaigns have been intensified, and we are opening up more diagnosis and treatment centres with the aim of improving the accessibility of these services," said Dr Ibrahim Idana, deputy director of the National TB Control Programme.

People with immune systems compromised by HIV are 50 times more likely to develop active TB, but the sputum tests most commonly used to detect TB often fail to recognise it in HIV-infected patients.

Idana said only about 30 percent of TB cases in Malawi were diagnosed using sputum tests. Health workers have to rely on other screening tools such as x-rays and biopsies for the 40 percent of TB patients who are sputum-negative, and the 23 percent who have TB in other organs besides the lungs. For TB patients who were on treatment before and are experiencing new episodes of the disease, culture samples are sent to the Central Reference Laboratory in Lilongwe to check for drug resistance, Idana told IRIN/PlusNews.

Despite the obvious links between HIV infection and TB, in most cases, co-infected patients still have to attend two seperate clinics to access treatment. Adamson Muula, a lecturer in community health at the College of Medicine in Blantyre, Malawi's commercial capital, explained that while TB clinics could be manned by health surveillance assistants (Malawi's lowest qualified cadre of health workers), HIV clinics had to be manned by a clinical officer or doctor. "There are few clinical officers and medical doctors to provide both TB drugs and ARVs [antiretroviral drugs], compelling patients to attend two clinics," he said.

Treatment under one roof

At Chiradzulu district hospital, about 40km outside Blantyre, the government, in collaboration with international medical relief organisation, Medecins San Frontieres (MSF), is providing medical services to scores of TB and HIV patients from surrounding districts. Some even come from urban Blantyre, where the shortage of health workers at Queen Elizabeth Central Hospital, Malawi's largest infirmary, has limited capacity.

MSF provides human resource support and equipment to existing government programmes aimed at TB and HIV prevention and treatment. "Our collaborated efforts have helped TB patients who are also HIV positive to get all the treatment they need at one site," said Gerald Zomba of MSF France.

Chiradzulu has a 40-bed in-patient facility in the TB ward, but so far only two cases of MDR-TB have been identified, according to Zomba. Last year, the programme achieved a 78 percent treatment success rate, not far behind the target of 85 percent recommended by the WHO.

Similar programmes are being put in place at Blantyre's Queen Elizabeth Central Hospital, at Kamuzu Central Hospital in Lilongwe, and several other district hospitals around the country.

Chimbali, of the National TB Control Programme, said the HIV/AIDS Unit in the Ministry of Health was working with his organisation to ensure the success of joint TB/HIV programmes. All patients diagnosed with TB were encouraged to test for HIV.

However, "Most TB patients who are also HIV positive have problems accessing ART [antiretroviral therapy], just as is the case with TB patients having problems accessing counselling and testing services [for HIV infection]," he said.

Health workers also ran the risk of becoming infected with TB in spite of precautionary measures taken while treating patients. A nurse at a TB clinic in Blantyre said it was easy to become infected. "It's a challenge that government has to look into," she said.

Muula said limited resources and a lack of pressure from health workers to push authorities to provide safer working environments was jeopardising their health. "There is evidence from the Ministry of Health's own reports that health workers have a high incidence of TB."