Occupational HIV Transmission Among Male Adult Film Performers — Multiple States, 2014

The use of antiretroviral medications in HIV-negative individuals as pre-exposure prophylaxis (PrEP) is a promising approach to prevent HIV infection. Tenofovir disoproxil fumarate (TDF) and emtricitabine exhibit desirable properties for PrEP including: favourable pharmacokinetics that support infrequent dosing; few major drug-drug or drug-food interactions; an excellent clinical safety record; and pre-clinical evidence for efficacy. Several large, randomized, controlled clinical trials are evaluating the safety and efficacy of TDF and emtricitabine for this new indication. A thorough understanding of variability in drug response will help determine future investigations in the field and/or implementation into clinical care. Because tenofovir and emtricitabine are nucleos(t)ide analogues, the HIV prevention and toxicity effects depend on the triphosphate analogue formed intracellularly. This review identifies important cellular pharmacology considerations for tenofovir and emtricitabine, which include drug penetration into relevant tissues and cell types, race/ethnicity/pharmacogenetics, gender, cellular activation state and appropriate episodic or alternative dosing strategies based on pharmacokinetic principles. The current state of knowledge in these areas is summarized and the future utility of intracellular pharmacokinetics/pharmacodynamics for the PrEP field is discussed.

Adult film production is a legal, multibillion dollar industry in California. In response to reports of human immunodeficiency virus (HIV) transmission by an adult film worker, we sought to determine the extent of HIV infection among exposed workers and to identify means of improving worker safety. The Los Angeles County Department of Health Services initiated an outbreak investigation that included interviews of infected workers to elicit information about recent sex partners, review of the testing agency's medical records and laboratory results, molecular analysis of HIV isolates from the 4 infected workers, and a risk assessment of HIV transmission in the adult film industry. Many adult film workers participate in a monthly program of screening for HIV infection by means of polymerase chain reaction-based technology to detect HIV DNA in blood. A male performer tested negative for HIV on 12 February 2004 and 17 March 2004, then tested positive for HIV on 9 April 2004. During the period between the negative test results, he experienced a flulike illness after performing unprotected vaginal and anal intercourse for an adult film produced outside the United States by a US company. After returning to California, he performed unprotected sex acts for adult films with 13 female partners who had all tested negative for HIV in the preceding 30 days; 3 subsequently tested positive for HIV (a 23% attack rate). Contact tracing identified no reasonable sources of infection other than the male index patient. Although current testing methods may shorten the window period to diagnosis of new HIV infection, they fail to prevent occupational acquisition of HIV in this setting. A California Occupational Safety and Health Administration-approved written health and safety program that emphasizes primary prevention is needed for this industry.

Limited information is available to describe the molecular epidemiology of HIV-1 in Bulgaria. To better understand the genetic diversity and the epidemiologic dynamics of HIV-1 we analyzed 125 new polymerase (pol) sequences from Bulgarians diagnosed through 2009 and 77 pol sequences available from our previous study from persons infected prior to 2007. Epidemiologic and demographic information was obtained from each participant and phylogenetic analysis was used to infer HIV-1 evolutionary histories. 120 (59.5%) persons were infected with one of five different HIV-1 subtypes (A1, B, C, F1 and H) and 63 (31.2%) persons were infected with one of six different circulating recombinant forms (CRFs; 01_AE, 02_AG, 04_cpx, 05_DF, 14_BG, and 36_cpx). We also for the first time identified infection with two different clusters of unique A-like and F-like sub-subtype variants in 12 persons (5.9%) and seven unique recombinant forms (3.5%), including a novel J/C recombinant. While subtype B was the major genotype identified and was more prevalent in MSM and increased between 2000–2005, most non-B subtypes were present in persons ≥45 years old. CRF01_AE was the most common non-B subtype and was higher in women and IDUs relative to other risk groups combined. Our results show that HIV-1 infection in Bulgaria reflects the shifting distribution of genotypes coincident with the changing epidemiology of the HIV-1 epidemic among different risk groups. Our data support increased public health interventions targeting IDUs and MSM. Furthermore, the substantial and increasing HIV-1 genetic heterogeneity, combined with fluctuating infection dynamics, highlights the importance of sustained and expanded surveillance to prevent and control HIV-1 infection in Bulgaria.