Highly diverse MLVA-ompA genotypes of rectal Chlamydia trachomatis among men who have sex with men in Brighton, UK and evidence for an HIV-related sexual network.

Objectives: In this prospective study, we aimed to determine the distribution of genotypes by multilocus variable number tandem repeat (VNTR) analysis plus analysis of the ompA gene (MLVA-ompA) of rectal Chlamydia trachomatis among men who have sex with men (MSM) attending Brighton Genitourinary Medicine (GUM) Clinic and to examine any correlations with clinical variables, including HIV status, and to isolate rectal C. trachomatis cultures maximising the possibility of obtaining complete genotyping data.Methods: Samples were assigned genotypes by PCR and sequencing of the markers of the MLVA-ompA genotyping system. Rectal C. trachomatis was isolated in cell culture using McCoy cells. Data regarding demographics, HIV status, rectal symptoms and history of sexually transmitted infections, including C. trachomatis, were collected.Results: 1809 MSM attending the clinic between October 2011 and January 2013 took part in the study, 112 (6.2%) of whom had rectal samples that tested positive for C. trachomatis. 85/112 (75.9%) C. trachomatis-positive rectal samples were assigned 66 different genotypes. Two distinct genotype subclusters were identified: subcluster 1 consisted of more HIV-negative men than subcluster 2 (p=0.025), and the MLVA-ompA genotypes in these subclusters reflected this. Isolates were successfully cultured from 37 of the 112 specimens, from which 27 otherwise unobtainable (from direct PCR) MLVA-ompA genotypes were gained.Conclusions: The most prevalent genotypes were G, E and D representing some overlap with the heterosexual distribution in UK. Subcluster 1 consisted of more ‘heterosexual genotypes’ and significantly more HIV-negative men than subcluster 2, associated with ‘MSM genotypes’. There was a higher diversity of C. trachomatis strains among MSM in Brighton than observed in other cities.<br/

Detailed molecular epidemiology of Chlamydia trachomatis in the population of Southampton attending the genitourinary medicine clinic in 2012-13 reveals the presence of long established genotypes and transitory sexual networks

Chlamydia trachomatis is the most common sexually transmitted infection (STI) in England. Our objective was to perform a detailed survey of the molecular epidemiology of C. trachomatis in the population of Southampton UK attending the genitourinary medicine clinic (GUM) to seek evidence of sexual network activity. Our hypothesis was that certain genotypes can be associated with specific demographic determinants. 380 positive samples were collected from 375 C. trachomatis positive GUM attendees out of the 3118 who consented to be part of the survey. 302 of the positive samples were fully genotyped. All six of the predominant genotypes possessed ompA locus type E. One ward of Southampton known to contain a large proportion of students had a different profile of genotypes compared to other areas of the city. Some genotypes appeared embedded in the city population whilst others appeared transient. Predominant circulating genotypes remain stable within a city population whereas others are sporadic. Sexual networks could be inferred but not conclusively identified using the data from this survey.</p

Distribution of <i>omp</i>A genotypes (as a percentage of the total positives for the city, n = 223) in regions of the city of Southampton.

<p>Colour coding shows Southampton wards or ward-groups represented by four-digit postcodes: blue = SO14; red = SO15; green = SO16; purple = SO17; light blue = SO18; and orange = SO19.</p

MLVA-<i>omp</i>A genotypes common between 2009[16] and 2012–13 studies.

<p>MLVA-<i>omp</i>A genotypes common between 2009[<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0185059#pone.0185059.ref016" target="_blank">16</a>] and 2012–13 studies.</p

Detailed molecular epidemiology of <i>Chlamydia trachomatis</i> in the population of Southampton attending the genitourinary medicine clinic in 2012-13 reveals the presence of long established genotypes and transitory sexual networks

<div><p><i>Chlamydia trachomatis</i> is the most common sexually transmitted infection (STI) in England. Our objective was to perform a detailed survey of the molecular epidemiology of <i>C</i>. <i>trachomatis</i> in the population of Southampton UK attending the genitourinary medicine clinic (GUM) to seek evidence of sexual network activity. Our hypothesis was that certain genotypes can be associated with specific demographic determinants. 380 positive samples were collected from 375 <i>C</i>. <i>trachomatis</i> positive GUM attendees out of the 3118 who consented to be part of the survey. 302 of the positive samples were fully genotyped. All six of the predominant genotypes possessed <i>omp</i>A locus type E. One ward of Southampton known to contain a large proportion of students had a different profile of genotypes compared to other areas of the city. Some genotypes appeared embedded in the city population whilst others appeared transient. Predominant circulating genotypes remain stable within a city population whereas others are sporadic. Sexual networks could be inferred but not conclusively identified using the data from this survey.</p></div

MLVA-<i>omp</i>A genotypes represented by three or more samples unique to 2012–13.

<p>MLVA-<i>omp</i>A genotypes represented by three or more samples unique to 2012–13.</p