When discussing the effects of transnational migration and global cities being built and run on the "backs" of those less fortunate immigrants (many times illegally), this influx of various individuals and their ability to pass through to urban, global areas and then back to their local areas, which has caused different levels of contact between communities, has also fed, especially in the region of South Africa, into the increased spread of various diseases and especially HIV.
People in this area are able to travel, meet, and mix with people they were not able to before and because of ignorance, the inability to practice safety precautions, and individual's choices (having more than one sexual partner (sometimes in different areas at the same time, and not practicing safety in regards to this) the spread of HIV in this newly transnational area has increased exceedingly.
A new study by Oxford and London scientists suggests that acquired infections within the UK are predominantly originating in sub-Saharan Africa.
On the other hand, the BMJ paper finds that 90 per cent of heterosexuals infected with HIV acquired the virus outside the UK, suggesting that onward heterosexual transmission in the UK is being controlled reasonably well. In contrast, our research shows that over the last 15 years at least six chains of onward transmission among men having sex with men have become established. So a substantial proportion of infections in men having sex with men are acquired in the UK, rather than abroad.