Commentary: Sifting through the maze of viral and host diversity and HIV/AIDS clinical progression

Costello and colleagues describe survival in a cohort of HIV-1 subtype E (circulating recombinant form 01_AE) infected patients in northern Thailand. In Thailand subtype B (Thai B) is endemic primarily among injecting drug users whereas subtype E began among female prostitutes and spread through their male clientele to heterosexual couples. Subtype E viruses are now also spreading among the injecting drug user networks. This study is of interest because of the geographical setting the patient population and the viral subtype. We have accumulated considerable knowledge regarding host and viral factors that influence infection pathogenesis and disease progression. Additionally environmental and socioeconomic factors including nutrition ability to access care and other endemic co-morbidities will influence disease progression. The association of different rates of disease progression in populations infected with different subtypes is not in itself a new finding. In Africa infection with subtype A was associated with a slower disease progression compared with non-A subtypes particularly subtype D. Nevertheless most of our knowledge still comes from subtype B infected patients living in the developed world. This study adds to a nascent body of knowledge regarding diverse subtypes of HIV in diverse populations. (excerpt)