Monday, September 12, 2011
TB and Injecting Drug Users
Part 1: Are IDUs the most potential candidates for MDR-TB and HIV co-infection?
Conversion of latent TB infection into TB disease is accelerated by the influence of HIV. The people living with HIV and AIDS have 60-70% more chances to be affected by TB in their life time. TB remains as the major killer of the people living with HIV and AIDS worldwide.
MDR TB (Multi Drug Resistant TB) is caused by Mycobacterium Tuberculosis strain which is resistant to two of the key anti-TB drugs – Rifampicin and Isoniazid. It is a gradually increasing problem which is evolving in many countries and raising steeper challenge in the TB control initiatives of the countries. Chronic dug defaulters, poor airborne infection control in the healthcare set ups and irrational usage of antibiotics by the healthcare providers are key reasons that give rise to MDR-TB. The treatment of MDR TB is 100 times costlier than treatment of normal TB and needs prolong treatment (daily therapy for 24 – 27 months). XDR-TB is the severe form of DR resistant TB where person affected by MDR TB shows resistance to several drugs used to treat a MDR-TB patient including valuable injectable medicines.
HIV transmission is highly enhanced among the drug users who inject drugs into their bodies and share needles and syringes. Sharing of injecting tools is actually the culture of the drug users, especially those who are poor, illiterate and belong to the low socio-economic strata of the society. The culture is attached with a strong recreational value that is still existing in many parts of the world and helping rapid transmission of HIV. Though evolvement of the harm reduction strategies like NSE (needle syringe exchange), OST (oral substitution therapy) are becoming popular and gradually accepted and adopted in the country’s HIV/AIDS policy, rapidly increasing HIV transmission, especially among IDUs in the countries of Central Asia and Eastern Europe is a source of major concern. Political unrest, drug trafficking, high level stigma and social intolerance towards drug users and inadequate policies and strategies to tackle the HIV epidemic among the criminalized high risk population groups chiefly IDUs and sex workers are flaring up the problem. There are increasing evidences of overlapping of sex work and injecting drugs in many places of this region. Selling sex for buying drugs and sharing injecting tools with IDU partners – sex workers are being affected in both ways.
Recently, to add fuel to the spreading fire, association between MDR-TB and HIV has been established in countries like Latvia, Estonia and Moldova indicating HIV infected individuals are at higher risk to harbour DR TB strains. This survey concurs with the earlier reported survey conducted in Ukraine in 2006. Furthermore, in Lithuania – where drug resistance data could not be disaggregated by HIV-negative and unknown HIV status – HIV-positive TB patients had a 8.4 (95% CI: 2.7–28.2) times higher odds of harbouring MDR-TB strains than TB patients for whom HIV status was unknown, indicating a possible association of the two epidemics. 2 studies in Thailand showed such association where many IDUs were there in the study group.
Let’s have a look at the HIV situation of these countries of Eastern Europe.
Estonia has already demonstrated the highest rate of HIV transmission and highest adult national HIV prevalence in Western and Central Europe. As per the current statistics of the country 6444HIV infected cases has been registered in the country though as per WHO data one as for one hundred adult Estonians is infected by HIV. The transmission of HIV in this country has been chiefly occurring through sharing of contaminated needles and syringes among the IDUs and HIV prevalence among IDUs has been estimated as high as 72%.
In Latvia, HIV prevalence has double the European Union average rate but remains below Estonia and a few other European countries. 3981 cases have been registered as of 2007 and 63.2 % of the infected population is IDUs.
Lithuania has the lowest HIV prevalence among the Baltic states, out of 1300 registered cases as of 2007 (as per the official data of the country’s AIDS centre), 75% is IDU.
Ukraine is the first country to reach estimated HIV prevalence of 1.5% among the age group 0f 15 – 49 years and a majority of them are IDUs. HIV prevalence among the IDUs is estimated to be between 39 – 50%.
In Moldova, despite the apparent changes of transmission patterns, the HIV epidemic is largely concentrated among the IDUs.
In Georgia, in 2009-10, MDR among new TB cases, previously treated TB cases and TB/HIV co-infected cases were 6%, 27.4% and 23.8% respectively, denoting strong suspicion towards association of MDR-TB and HIV. Georgia is a low-prevalence country with widespread of IDUs. According to the UNODC report Georgia has the highest rate of opiate abuse (.6% of adult population) of the Caucasus countries.
It is evident that 50 – 70% of the HIV infected population of these countries belong to groups of IDUs.
If these countries have also established association between MDR-TB and HIV, doesn’t it also indicate that the IDUs are actually the first and foremost victims of the deadliest co-infection?
Unfortunately, it is not possible to come to such conclusion now because of lack of global data, especially related to IDUs who have been affected by TB or TB/HIV.