3. Hecht FM, Busch MP, Rawal B, Webb M, Rosenberg E, et al. (2002) Use of laboratory tests and clinical symptoms for identification of primary HIV infection. AIDS 16: 1119–1129. 4. Lyles RH, Munoz A, Yamashita TE, Bazmi H, Detels R, et al. (2000) Natural history of human immunodeficiency virus type 1 viremia after seroconversion and proximal to AIDS in a large cohort of homosexual men. J Infect Dis 181: 872–880. 5. Saah AJ, Hoover DR, Weng S, Carrington M, Mellors J, et al. (1998) Association of HLA profiles with early plasma viral load, CD4+ cell count and rate of progression to AIDS following acute HIV-1 infection. AIDS 12: 2107–2113. 6. Vanhems P, Voirin N, Hirschel B, Cooper DA, Vizzard J, et al. (2003) Incubation and duration of specific symptoms at acute retroviral syndrome as independent predictors of progression to AIDS. J Acquir Immune Defic Syndr 32: 542–544. 7. Bollinger RC, Brookmeyer RS, Mehendale SM, Paranjape RS, Shepherd ME, et al. (1997) Risk factors and clinical presentation of acute primary HIV infection in India. JAMA 278: 2085–2089. 8. Lavreys L, Thompson ML, Martin HL Jr., Mandaliya K, Ndinya-Achola JO, et al. (2000) Primary human immunodeficiency virus type 1 infection: clinical manifestations among women in Mombasa, Kenya. Clin Infect Dis 30: 486–490. 9. Abdool Karim Q, Abdool Karim SS, Soldan K, Zondi M (1995) Reducing the risk of HIV infection among South African Sex Workers: Socioeconomic and Gender Barriers. Am J Public Health 85: 1521–1525. 10. Ramjee G, Karim SS, Sturm AW (1998) Sexually transmitted infections among sex workers in KwaZulu-Natal, South Africa. Sex Transm Dis 25: 346–349. 11. Ramjee G, Morar NS, Alary M, Mukenge-Tshibaka L, Vuylsteke B, et al. (2000) Challenges in the conduct of vaginal microbicide effectiveness trials in the developing world. AIDS 14: 2553–2557. 12. Gouws E (2005) HIV Incidence Rates in South Africa. In: Abdool Karim S, Abdool Karim Q, eds. HIV/AIDS in South Africa. New York: Cambridge University Press. pp 67–76. 13. Dunkle KL, Jewkes RK, Brown HC, Gray GE, McIntryre JA, et al. (2004) Transactional sex among women in Soweto, South Africa: prevalence, risk factors and association with HIV infection. Soc Sci Med 59: 1581–1592. 14. Shisana O, Rehle T, Simbayi LC, Parker W, Zuma K, et al. (2005) South African National HIV Prevalence, HIV Incidence, Behaviour and Communi- cation Survey, 2005. Cape Town: HSRC Press. pp 33–50. 15. Allen TM, Altfeld M, Geer SC, Kalife ET, Moore C, et al. (2005) Selective escape from CD8+ T-cell responses represents a major driving force of human CAPRISA 002 Study immunodeficiency virus type 1 (HIV-1) sequence diversity and reveals constraints on HIV-1 evolution. J Virol 79: 13239–13249. 16. Begaud E, Chartier L, Marechal V, Ipero J, Leal J, et al. (2006) Reduced CD4 T cell activation and in vitro susceptibility to HIV-1 infection in exposed uninfected Central Africans. Retrovirology 3: 35. 17. Fowke KR, Dong T, Rowland-Jones SL, Oyugi J, Rutherford WJ, et al. (1998) HIV type 1 resistance in Kenyan sex workers is not associated with altered cellular susceptibility to HIV type 1 infection or enhanced beta-chemokine production. AIDS Res Hum Retroviruses 14: 1521–1530. 18. Kiepiela P, Leslie AJ, Honeyborne I, Ramduth D, Thobakgale C, et al. (2004) Dominant influence of HLA-B in mediating the potential co-evolution of HIV and HLA. Nature 432: 769–775. 19. Martin G, Tremblay MJ (2004) HLA-DR, ICAM-1, CD40, CD40L, and CD86 are incorporated to a similar degree into clinical human immunodeficiency virus type 1 variants expanded in natural reservoirs such as peripheral blood mononuclear cells and human lymphoid tissue cultured ex vivo. Clin Immunol 111: 275–285. 20. Paxton WA, Martin SR, Tse D, O’Brien TR, Skurnick J, et al. (1996) Relative resistance to HIV-1 infection of CD4 lymphocytes from persons who remain uninfected despite multiple high-risk sexual exposure. Nat Med 2: 412–417. 21. Rowland-Jones SL, Dong T, Fowke KR, Kimani J, Krausa P, et al. (1998) Cytotoxic T cell responses to multiple conserved HIV epitopes in HIV-resistant prostitutes in Nairobi. J Clin Invest 102: 1758–1765. 22. Stremlau M, Owens CM, Perron MJ, Kiessling M, Autissier P, et al. (2004) The cytoplasmic body component TRIM5alpha restricts HIV-1 infection in Old World monkeys. Nature 427: 848–853. 23. Truong LX, Luong TT, Scott-Algara D, Versmisse P, David A, et al. (2003) CD4 cell and CD8 cell-mediated resistance to HIV-1 infection in exposed uninfected intravascular drug users in Vietnam. AIDS 17: 1425–1434. 24. Steyn K, Gaziano TA, Bradshaw D, Laubscher R, Fourie J (2001) Hypertension in South African adults: results from the demographic and health survey, 1998. J Hypertens 19: 1717–1725. 25. Mlisana K, Auld SC, Grobler A, van Loggerenberg F, Williamson C, et al. (2008) Anaemia in Acute HIV-1 Subtype C Infection. PLoS ONE 3: e1626. 26. West GR, Corneli AL, Best K, Kurkjian KM, Cates W Jr. (2007) Focusing HIV prevention on those most likely to transmit the virus. AIDS Educ Prev 19: 275–288. 27. Abdool Karim SS, Mlisana K, Kharsany AB, Williamson C, Baxter C, et al. (2007) Utilizing nucleic acid amplification to identify acute HIV infection. AIDS 21: 653–655. PLoS ONE | www.plosone.org 8 April 2008 | Volume 3 | Issue 4 | e1954