Cases of pediatric XDR-TB have been reported in most countries including the United States.In 2006 an outbreak of XDR-TB South Africa was first reported as a cluster of 53 patients in a rural hospital in KwaZulu-Natal, with all but one dying. What was particularly worrying was that the mean survival from sputum specimen collection to death was only 16 days and that the majority of patients had never previously received treatment for tuberculosis. This is the epidemic for which the acronym XDR-TB was first used, although TB strains that fulfil the current definition have been identified retrospectively, this was the largest group of linked cases ever found. Since the initial report in September 2006, cases have now been reported in most provinces in South Africa. As of 16 March 2007, there were 314 cases reported, with 215 deaths. It is clear that the spread of this strain of TB is closely associated with a high prevalence of HIV and poor infection control; in other countries where XDR-TB strains have arisen, drug-resistance has arisen from mismanagement of cases or poor patient compliance with drug treatment instead of being transmitted from person to person. This strain of TB does not respond to any of the drugs currently available in South Africa for first- or second-line treatment. It is now clear that the problem has been around for much longer than health department officials have suggested, and is far more extensive. By 23 November 2006, 303 cases of XDR-TB had been reported, of which 263 were in KwaZulu-Natal.
The probability of resistance is higher in those patients who relapse and every effort must be made to obtain a specimen that can be cultured for sensitivities. That said, most patients who relapse do so with a fully sensitive strain and it is possible that these patients have not relapsed, but have instead been re-infected; these patients can be re-treated with the same regimen as before (no drugs need to be added to the regimen and the duration need not be any longer). The WHO recommends a regimen of 2SHREZ/6HRE when microbiology is not available (the majority of countries where TB is highly endemic). This regimen was designed to provide optimal treatment for fully sensitive TB (the most common finding in patients who have relapsed) as well as to cover the possibility of INH-resistant TB (the most common form of resistance found). Because of the lifelong risk of relapse, all patients should be warned of the symptoms of TB relapse upon finishing treatment and given strict instructions to return to their doctor if symptoms recur. Public health and health policy
As of 2010, India has more reported cases of TB than any other country. This is in part due to severe mismanagement of diagnosis and treatment of TB within the private health care sector of India that serves about 50% of the population. There are therefore calls for the private sector to engage in the public Revised National Tuberculosis Control Program that has proved effective in reducing TB amongst the patients receiving health care through the government.