It seems unlikely to come into contact with only a single cell... although a strange thing about HIV is that it seems only a single viral particle usually gets

It seems unlikely to come into contact with only a single cell... although a strange thing about HIV is that it seems only a single viral particle usually gets transmitted from one person to another. Even though there are millions of variants in each infected person only a single one is usually passed on: >"The reverse transcriptase of HIV lacks proofreading activity, the ability to confirm that the DNA transcript it makes is an accurate copy of the RNA code, and confers a mutation rate of approximately 3.4×10−5 mutations per base pair per replication cycle. Since the HIV genome is an estimated 104 base pairs in length and the baseline rate of viral production is approximately 1010 virions per day, millions of viral variants are produced within any infected person in a single day." https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2614444/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2614444/ >"Transmission of a single viral variant occurs in about 76–90% of cases of heterosexual transmission [2], [6], [7], in about 60% of cases of HIV-1-infected men who have sex with men (MSM) [5], and only in about 40% of injection drug users (IDU) who acquired HIV-1 infection [4]." https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0016714 https://journals.plos.org/plosone/article?id=10.1371/journal...