Insights:
HIV is a major cause of secondary immunodeficiency. Its geographic distribution reflects its own phenotypic variation. There's HIV-1 and HIV-2. Of HIV-1, there's an M type, N and O type. Of the M type of HIV-1, there are clades A to K, each with their own geographic distribution.
Reference
Kumar, V. (2017). Robbins basic pathology international edition. [S.l.]: Elsevier - Health Science.
Abbas, A., Pillai, S. and Lichtman, A. (2018). Cellular and molecular immunology. Philadelphia [etc.]: Elsevier.