Pocket Global Health

Tuberculosis continues to be a global health issue of epidemic proportions.  Fueled by co-infection with HIV, TB is one of the leading ultimate causes of death for HIV positive patients.  Recent years have also brought new challenges with the emergence of multi-drug resistant (MDR) and extensively drug resistant (XDR) strains of the disease.

A new WHO initiative expands diagnostic laboratories, treatment resources, and research on the subject.

Link above from the New Yorker…

Great article about the challenges in diagnosing tuberculosis and the risks of treating falsely diagnosed patients.  New techniques of genetic testing for TB (rather than antibody and microscopic approaches) will hopefully be implemented around the world over the coming years.

Tuberculosis is a difficult disease to diagnose, relying on subjective analysis of stains or a prolonged wait for a culture & sensitivity.  Even a series of negative results does not completely rule out the disease.

A new rapid diagnostic method, based on DNA analysis, has recently been endorsed as a global health tool to fight the disease.  Increased accurate diagnosis can lead to more effective treatment, and therefore fewer people exposed to the disease in the future.

A new cellular target has been discovered that researchers hope will lead to a future vaccine.  Currently the BCG vaccine is only effective at preventing infant TB-meningitis.  It does not offer any significant protection against the pulmonary TB that causes the bulk of the 2 million annual deaths from the disease.

An important concept in TB is the difference between “infection” and “disease.”  In Botswana, some estimate that 80% of population has been infected with TB, although most of them will live their entire lives without symptoms.  A TB “infected” person has a lifetime risk of developing active TB disease of 10%.  The issue is complicated however, by HIV.  An HIV + person, infected with TB, has a annual risk of developing active TB disease of 10%.

Link above to Reuters…

A new TB vaccine is currently undergoing clinical trials.  If it proves to be safe and efficacious, it can replace the BCG vaccine.  The BCG has reduced the incidence of tuberculous meningitis in infants, but it does not seem to offer much protection against adult pulmonary tuberculosis.

Link above to Reuters…

The blood test, manufactured in the west but used mostly in private clinics in developing countries, has been proven to be wildly inaccurate.  The consequence being that people with TB are not getting treatment, and others without TB are being exposed to anti-tuberculosis therapies unnecessarily. 

Link above to the BBC…

TB strains resistant to all forms of medication have been isolated in India.

Link above to Reuters…

New drugs on the horizon that can cure TB in weeks instead of months…

Link above to Reuters…

In a study harkening back to the days of “heliotherapy” for TB, vitamin D (from sun exposure) has been shown to improve outcomes of patients receiving traditional multi-drug anti-tuberculosis therapy.