SciCombinator

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Concept: Sexually transmitted disease

321

In December 2013, during a Zika virus (ZIKV) outbreak in French Polynesia, a patient in Tahiti sought treatment for hematospermia, and ZIKV was isolated from his semen. ZIKV transmission by sexual intercourse has been previously suspected. This observation supports the possibility that ZIKV could be transmitted sexually.

Concepts: HIV, AIDS, Sexual intercourse, Semen, Sexually transmitted disease, Human sexual behavior, Pacific Ocean, French Polynesia

225

Concern about young people’s sexuality is focused on the need to prevent harmful outcomes such as sexually transmitted infections and unplanned pregnancy. Although the benefit of a broader perspective is recognized, data on other aspects of sexuality, particularly sexual function, are scant. We sought to address this gap by measuring the population prevalence of sexual function problems, help seeking, and avoidance of sex in young people.

Concepts: Pregnancy, Sexual intercourse, Oral sex, Sexually transmitted disease, Human sexual behavior, Human sexuality, Sexuality

156

Background Antiretroviral preexposure prophylaxis has been shown to reduce the risk of human immunodeficiency virus type 1 (HIV-1) infection in some studies, but conflicting results have been reported among studies, probably due to challenges of adherence to a daily regimen. Methods We conducted a double-blind, randomized trial of antiretroviral therapy for preexposure HIV-1 prophylaxis among men who have unprotected anal sex with men. Participants were randomly assigned to take a combination of tenofovir disoproxil fumarate (TDF) and emtricitabine (FTC) or placebo before and after sexual activity. All participants received risk-reduction counseling and condoms and were regularly tested for HIV-1 and HIV-2 and other sexually transmitted infections. Results Of the 414 participants who underwent randomization, 400 who did not have HIV infection were enrolled (199 in the TDF-FTC group and 201 in the placebo group). All participants were followed for a median of 9.3 months (interquartile range, 4.9 to 20.6). A total of 16 HIV-1 infections occurred during follow-up, 2 in the TDF-FTC group (incidence, 0.91 per 100 person-years) and 14 in the placebo group (incidence, 6.60 per 100 person-years), a relative reduction in the TDF-FTC group of 86% (95% confidence interval, 40 to 98; P=0.002). Participants took a median of 15 pills of TDF-FTC or placebo per month (P=0.57). The rates of serious adverse events were similar in the two study groups. In the TDF-FTC group, as compared with the placebo group, there were higher rates of gastrointestinal adverse events (14% vs. 5%, P=0.002) and renal adverse events (18% vs. 10%, P=0.03). Conclusions The use of TDF-FTC before and after sexual activity provided protection against HIV-1 infection in men who have sex with men. The treatment was associated with increased rates of gastrointestinal and renal adverse events. (Funded by the National Agency of Research on AIDS and Viral Hepatitis [ANRS] and others; ClinicalTrials.gov number, NCT01473472 .).

Concepts: Antiretroviral drug, HIV, AIDS, Sexual intercourse, Oral sex, Tenofovir, Sexually transmitted disease, Human sexual behavior

147

Weak intracellular penetration of antibiotics makes some infections difficult to treat. The Trojan horse strategy for targeted drug delivery is among the interesting routes being explored to overcome this therapeutic difficulty. Chlamydia trachomatis, as an obligate intracellular human pathogen, is responsible for both trachoma and sexually transmitted diseases. Chlamydia develops in a vacuole and is therefore protected by four membranes (plasma membrane, bacterial inclusion membrane, and bacterial membranes). In this work, the iron-transport protein, human serum-transferrin, was used as a Trojan horse for antibiotic delivery into the bacterial vacuole. Amoxicillin was grafted onto transferrin. The transferrin-amoxicillin construct was characterized by mass spectrometry and absorption spectroscopy. Its affinity for transferrin receptor 1, determined by fluorescence emission titration [KaffTf-amox = (1.3 ± 1.0) x 108], is very close to that of transferrin [4.3 x 108]. Transmission electron and confocal microscopies showed a co-localization of transferrin with the bacteria in the vacuole and were also used to evaluate the antibiotic capability of the construct. It is significantly more effective than amoxicillin alone. These promising results demonstrate targeted delivery of amoxicillin to suppress Chlamydia and are of interest for Chlamydiaceae and maybe other intracellular bacteria therapies.

Concepts: Bacteria, Cell membrane, Sexually transmitted disease, Chlamydiae, Chlamydia, Chlamydia trachomatis, Chlamydiaceae, Trachoma

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86

In 2014, the California Department of Public Health was notified by a local health department of a diagnosis of acute human immunodeficiency virus (HIV) infection* and rectal gonorrhea in a male adult film industry performer, aged 25 years (patient A). Patient A had a 6-day history of rash, fever, and sore throat suggestive of acute retroviral syndrome at the time of examination. He was informed of his positive HIV and gonorrhea test results 6 days after his examination. Patient A had a negative HIV-1 RNA qualitative nucleic acid amplification test (NAAT)(†) 10 days before symptom onset. This investigation found that during the 22 days between the negative NAAT and being informed of his positive HIV test results, two different production companies directed patient A to have condomless sex with a total of 12 male performers. Patient A also provided contact information for five male non-work-related sexual partners during the month before and after his symptom onset. Patient A had additional partners during this time period for which no locating information was provided. Neither patient A nor any of his interviewed sexual partners reported taking HIV preexposure prophylaxis (PrEP). Contact tracing and phylogenetic analysis of HIV sequences amplified from pretreatment plasma revealed that a non-work-related partner likely infected patient A, and that patient A likely subsequently infected both a coworker during the second film production and a non-work-related partner during the interval between his negative test and receipt of his positive HIV results. Adult film performers and production companies, medical providers, and all persons at risk for HIV should be aware that testing alone is not sufficient to prevent HIV transmission. Condom use provides additional protection from HIV and sexually transmitted infections (STIs). Performers and all persons at risk for HIV infection in their professional and personal lives should discuss the use of PrEP with their medical providers.

Concepts: HIV, AIDS, Reverse transcriptase, Oral sex, Sexually transmitted disease, Human sexual behavior, Sexually transmitted diseases and infections, Blood donation

66

Sexually transmitted infections are common causes of morbidity and mortality, including infertility and certain types of cancer. Alcohol tax increases may decrease sexually transmitted infection rates overall and differentially across population subgroups by decreasing alcohol consumption in general and prior to sex, thus decreasing sexual risk taking and sexually transmitted infection acquisition. This study investigated the effects of a Maryland increase in alcohol beverage sales tax on statewide gonorrhea and chlamydia rates overall and within age, gender, and race/ethnicity subpopulations.

Concepts: AIDS, Oral sex, Sexually transmitted disease, Human sexual behavior, Human sexuality, Chlamydia infection, Alcoholic beverage, Sexually transmitted diseases and infections

62

The damaged goods hypothesis posits that female performers in the adult entertainment industry have higher rates of childhood sexual abuse (CSA), psychological problems, and drug use compared to the typical woman. The present study compared the self-reports of 177 porn actresses to a sample of women matched on age, ethnicity, and marital status. Comparisons were conducted on sexual behaviors and attitudes, self-esteem, quality of life, and drug use. Porn actresses were more likely to identify as bisexual, first had sex at an earlier age, had more sexual partners, were more concerned about contracting a sexually transmitted disease (STD), and enjoyed sex more than the matched sample, although there were no differences in incidence of CSA. In terms of psychological characteristics, porn actresses had higher levels of self-esteem, positive feelings, social support, sexual satisfaction, and spirituality compared to the matched group. Last, female performers were more likely to have ever used 10 different types of drugs compared to the comparison group. A discriminant function analysis was able to correctly classify 83% of the participants concerning whether they were a porn actress or member of the matched sample. These findings did not provide support for the damaged goods hypothesis.

Concepts: Sexual intercourse, Oral sex, Sexually transmitted disease, Human sexual behavior, Human sexuality, Pornographic actor, Erotica, Child abuse

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Early initiation of sexual activity is associated with having more sexual partners, not using condoms, sexually transmitted infection (STI), and pregnancy during adolescence (1,2). The majority of adolescents initiate sexual activity during high school, and the proportion of high school students who have ever had sexual intercourse increases by grade; black students are more likely to have ever had sexual intercourse than are white students (3). The proportion of high school students overall who had ever had sexual intercourse did not change significantly during 1995-2005 (53.1% to 46.8%) (Division of Adolescent and School Health, National Center for HIV/AIDS, Viral Hepatitis, STD, and TB Prevention, CDC, unpublished data). To assess whether changes have occurred in recent years in the proportion of high school students who have ever had sexual intercourse, CDC examined trends overall and by grade, race/ethnicity, and sex among U.S. high school students, using data from the 2005-2015 national Youth Risk Behavior Surveys (YRBSs) and data from 29 states* that conduct the YRBS and have weighted data. Nationwide, the proportion of high school students who had ever had sexual intercourse decreased significantly overall and among 9th and 10th grade students, non-Hispanic black (black) students in all grades, and Hispanic students in three grades. A similar pattern by grade was observed in nearly half the states (14), where the prevalence of ever having had sexual intercourse decreased only in 9th grade or only in 9th and 10th grades; nearly all other states saw decreases in some or all grades. The overall decrease in the prevalence of ever having had sexual intercourse during 2005-2015 is a positive change in sexual risk among adolescents (i.e., behaviors that place them at risk for human immunodeficiency virus, STI, or pregnancy) in the United States, an overall decrease that did not occur during the preceding 10 years. Further, decreases by grade and race/ethnicity represent positive changes among groups of students who have been determined in previous studies to be at higher risk for negative outcomes associated with early sexual initiation, such as greater numbers of partners, condom non-use, teen pregnancy, and STI (1-3). More work is needed to understand the reasons for these decreases and to ensure that they continue.

Concepts: HIV, AIDS, Sexual intercourse, Oral sex, Adolescence, High school, Sexually transmitted disease, Human sexual behavior

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In 2015, the rate of reported primary and secondary syphilis in the United States was 7.5 cases per 100,000 population, nearly four times the previous lowest documented rate of 2.1 in 2000 (1). In 2015, 81.7% of male primary and secondary syphilis cases with information on the sex of the sex partner were among gay, bisexual, and other men who have sex with men (collectively referred to as MSM) (1). These data suggest a disproportionate incidence of disease among MSM. However, attempts to quantify this disparity have been hindered by limited data on the size of the MSM population at the state level. To produce the first estimates of state-specific rates of primary and secondary syphilis among MSM, CDC used MSM population estimates based on a new methodology (2) and primary and secondary syphilis case counts reported in 2015 to the National Notifiable Diseases Surveillance System. Among 44 states reporting information on the sex of sex partners for ≥70% of male cases, the overall rate of primary and secondary syphilis among all men (aged ≥18 years) in the United States in 2015 was 17.5 per 100,000, compared with 309.0 among MSM and 2.9 among men who reported sex with women only. The overall rate of primary and secondary syphilis among MSM was 106.0 times the rate among men who have sex with women only and 167.5 times the rate among women.* These data highlight the disproportionate impact of syphilis among MSM and underscore the need for innovative and targeted syphilis prevention measures at the state and local level, especially among MSM. It is important that health care providers recognize the signs and symptoms of syphilis, screen sexually active MSM for syphilis at least annually, and provide timely treatment according to national sexually transmitted diseases treatment guidelines (3).

Concepts: Sexual intercourse, United States, Oral sex, Sexually transmitted disease, Human sexual behavior, Human sexuality, Syphilis