Ruth Levine at the Global Health Policy Blog rightly points out that the emergence of Extreme Drug Resistant TB is a further example of the way that our interests, in rich countries, are increasingly intertwined with the interests of poor countries.
Recent reports about the emergence of Extreme Drug-Resistant TB in South Africa are disquieting reminders of fundamental concerns in international public health: fragile health systems in developing countries, stretched to the breaking point as they struggle to respond to health needs today, have the potential to incubate infectious diseases that are tomorrow's global threat. While the new strains of TB that are untreatable with any of current medications affect only small numbers at the moment, the insurgent microbes cannot be ignored.
As George Bush said in another context, we have to fight it over there so we don't have to fight it over here.
See also Christine Gorman at the Time Global Health blog