MicrobiologyBytes

The delightful NCBI ROFL carried this item recently. Certainly something to think about over the “festive” season.

Scent Recognition of Infected Status in Humans. J Sex Med. Dec 6 2011. doi: 10.1111/j.1743-6109.2011.02562.x
There is a body of experimental evidence that mice and rats use chemical signals to avoid sexual contact with infected conspecifics. In contrast to animals, body scent of sick humans is employed only in medical diagnostics. A modification of human body odor, due to an infection, has not been studied as a potential signal for choice of a sexual partner. It might, however, be especially important for sexually transmitted infections (STI) because many such infections have no obvious external manifestations.
Aim: In this study, we have investigated odor pleasantness of young men infected with gonorrhea, Neisseria gonorrhoeae.
Methods:We collected armpit sweat and saliva from young men (17-25 years old) belonging to three groups: healthy persons (N=16), young men infected with gonorrhea, Neisseria gonorrhoeae (N=13), and persons recovered due to specific therapy (N=5). The sweat samples odor was then assessed by healthy young women (17-20 years old). Concentrations of cortisol, testosterone, immunoglobulin A (IgA), and immunoglobulin G (IgG) were measured in saliva by means of enzyme-linked immunosorbent assay.
Main Outcome Measures: Subjective rates of odor pleasantness, association of scent of armpit sweat with odor descriptors, stepwise regression of odor pleasantness and salivary cortisol, testosterone, IgA, and IgG. Results: The odor from infected individuals was reported as less pleasant in comparison with the odor of healthy and recovered young men. The scent of infected men was more frequently associated by raters with the descriptor “putrid.” Odor pleasantness of the male sweat correlated negatively with concentration of the nonspecific salivary IgA and IgG, which was measured as an indicator of current immunoenhancement.
Conclusion: Perhaps, the immune-dependent reduction of the scent pleasantness in the acute phase of STI is part of an evolutionary mechanism ensuring, unconsciously, avoidance of a risky romantic partner.

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Chlamydia is the most prevalent bacterial sexually transmitted infection (STI) in the western world. In Ireland, the number of chlamydia notifications increased from 245 in 1995 to 6290 in 2008. While this may reflect a real rise in the burden of chlamydia infection, it also reflects an increase in provider awareness in chlamydia testing, test performance and the introduction of laboratory notification. The real burden (numbers of infection) is likely to be higher than reported as chlamydia is asymptomatic in approximately 70% of women and 50% of men and thus may remain undiagnosed. Prevalence studies in young Irish people (including students) have shown similar rates of infection to the UK and else where in Europe.

In view of the asymptomatic nature of chlamydia, especially in women, there is recognition that it is important to screen sexually active women aged less than 25 years. Two approaches are proposed: systematic, where all eligible young persons are systematically invited for screening, which requires the availability of a unique identifier for each individual to ensure all eligible persons are invited and not invited again except where indicated; and opportunistic, where eligible young persons that are visiting/utilising clinical and non-clinical settings are invited to take a test.

These issues highlight the need for additional strategies for screening that are free at the point of testing, easy to access, private and available in a variety of settings. Screening strategies need to be ‘youth friendly’ and available outside of traditional medical facilities.

Pee-in-a-Pot: acceptability and uptake of on-site chlamydia screening in a student population in the Republic of Ireland. (2010) BMC Infectious Diseases 10: 325 doi:10.1186/1471-2334-10-325
Background: The aim of the study was to explore the acceptability and uptake of on-campus screening using a youth friendly approach in two Third Level higher education institutions (HEIs). This study is part of wider research exploring the optimal setting for chlamydia screening in Ireland.
Methods: Male and female students were given the opportunity to take a free anonymous test for chlamydia during a one week programme of “pee-in-a-pot” days at two HEI campuses in the West of Ireland. The study was set up after extensive consultation with the two HEIs and advertised on the two campuses using a variety of media in the two weeks preceding the screening days. Screening involved the provision and distribution of testing packs at communal areas and in toilet facilities. In Ireland, chlamydia notifications are highest amongst 20-29 year olds and hence the screening criterion was aimed at 18-29 year olds. Urine samples were tested using a nucleic acid amplification test (NAAT). Following the screening days, qualitative in-depth interviews were conducted with participants about their experiences of the event.
Results: Out of 1,249 test kits distributed in two HEIs, 592 specimens were collected giving a return rate of 47.5%. Tests excluded (54) were due to labelling errors or ineligibility of participants’ age. Two thirds of those tested were females and the mean age was 21 years. Overall, 3.9% (21/538) of participants tested positive, 5% (17/336) among females and 2% (4/191) among males. Participant interviews identified factors which enhanced student participation such as anonymity, convenience, accessibility of testing, and the informal and non-medical approach to testing.
Conclusions: Screening for chlamydia using on-campus “pee-in-a-pot” days is an acceptable strategy in this population. This model can detect and treat asymptomatic cases of chlamydia and avoid many of the barriers associated with testing for sexually transmitted infections (STIs) in clinical settings.

Related:

• Telling partners about chlamydia – how ?
• Chlamydia Infection
• UK chlamydia cases up in under-16s
• Low uptake of Chlamydia screening in the UK

This summer on MicrobiologyBytes we’ll be revisiting a few old favourites – some of the most popular posts on this site. Today’s post is:

The first publications exploring the interface between sexually transmitted infections (STIs) and the Internet appeared in the 26 July 2000 issue of the Journal of the American Medical Association. In one article, Klausner et al. described a cluster of early syphilis cases among men having sex with men (MSM) who had met each other online. In the second article in the same issue, McFarlane et al. reported on a survey among clients of the Denver HIV counseling and testing program, showing that among MSM visiting the site, 25% had sex with at least one partner first met on the Internet. Together, these articles suggested that the Internet was emerging as a new risk environment for STIs and HIV. Since the publication of these articles, numerous studies have been conducted and published that have further investigated the role of the Internet, both as an STI/HIV risk “venue” as well as a potential place for the delivery of STI/HIV prevention services.

In recent years, the Internet and its users have undergone a fundamental transformation. Originally, the Internet was designed to allow access of information provided by the publisher of a given website. Although websites have become very sophisticated in how this information is presented and while the information given can be tailored to the individual user, the information stream is predominantly unidirectional from the website to the user, and the content of the site is determined by its owner. Examples include sites that aim to convey general information about businesses or organizations, for example, the website of the Centers for Disease Control and Prevention, or allow for minimal manipulation of personalized information, such as online banking or bill payment. In Internet terms, this use of the Internet is referred to as Web 1.0. By contrast, Web 2.0 comprises Internet applications in which the information stream is more or less reversed. Here, the content of a website is mostly driven by the users of the site. This information can take multiple forms, including a variety of uploaded file formats (text, graphics, audio, video), blogs (web-logs), vlogs (video logs), chats, etc. Social networking sites, including YouTube, MySpace, and FaceBook are among the prime examples of the Web 2.0 applications that have revolutionized Internet use in the last decade.

In this article, the authors discuss the implications of the shift from Web 1.0 to Web 2.0 technology on sexual health from three perspectives: the Internet as an STI risk environment, the Internet as a venue for STI prevention, and, finally, the Internet as a tool for STI service and prevention providers. The growth of the Internet as a communication medium has had far-reaching consequences for STI/HIV prevention ranging from a venue for partner recruitment with potential risk as well as prevention benefits, to the use of the Internet as a place to deliver STI/HIV prevention services in a variety of more or less interactive formats, and finally as a tool for the development of a prevention work force. However, while the Internet has great potential as an important STI/HIV prevention medium, it appears that the greatest potential is yet untapped and that the providers of these services are considerably lagging behind their target audience in the creative and innovative uses of the new medium.

Web 2.0 and beyond: risks for sexually transmitted infections and opportunities for prevention. Curr Opin Infect Dis. 2009 22(1): 67-71
The continued growth of the Internet as a communication medium has had major implications for the transmission and prevention of sexually transmitted infections (STIs). The purpose of this review is to describe recent developments in this rapidly changing environment. The interface between the Internet and STIs is described from three perspectives: the Internet as a risk environment, that is, a place where prospective, potentially STI-infected, sex partners can be recruited; the Internet as a venue where public health prevention interventions aimed at STIs and HIV prevention can be placed; and the Internet as an increasingly important work environment for all STI prevention disciplines. The review highlights recent developments and identifies potential avenues for future research and program development. The increasing interactivity of the Internet, known as ‘Web 2.0′, especially the user-driven social networking sites that allow users to share near limitless amounts of personal information with their peers in the network, is compounding the potential of the Internet as an environment for both STI risk and prevention.

Related:

• Health Risk Behaviors on MySpace
• You’ve Got Mail