Inga Velicko

Emergence and Spread of Chlamydia trachomatis Variant, Sweden

A variant of Chlamydia trachomatis that had escaped detection by commonly used systems was discovered in Sweden in 2006. In a nationwide study, we found that it is now prevalent across Sweden, irrespective of the detection system used. Genetic analysis by multilocus sequence typing identified a predominant variant, suggesting recent emergence.

Outbreak of norovirus in Västra Götaland associated with recreational activities at two lakes during August 2004

A large community outbreak of norovirus (NV) gastrointestinal infection occurred in Västra Götaland County, Sweden in August 2004, following attendance at recreational lakes. A frequency age-matched case control study was undertaken of persons who had attended these lakes to identify risk factors. 163 cases and 329 controls were included. Analysis indicates that having water in the mouth while swimming (OR = 4.7; 95% CI 1.1–20.2), attendance at the main swimming area at Delsjön Lake (OR = 25.5; 95% CI 2.5–263.8), taking water home from a fresh water spring near Delsjön lake (OR = 17.3; 95% CI 2.7–110.7) and swimming less than 20 m from shore (OR = 13.4; 95% CI 2.0–90.2) were significant risk factors. The probable vehicle was local contamination of the lake water (especially at the main swimming area). The source of contamination could not be determined

Nationwide measles epidemic in Ukraine: The effect of low vaccine effectiveness

The WHO European Region has a measles elimination target for 2010. Between September 2005 and mid-June 2006, more than 50,000 measles cases were reported in Ukraine; many reportedly had received two doses of measles vaccine and over 60% were among persons 15-29 years old. To investigate vaccine effectiveness (VE), a case-control study was undertaken in Dnepropetrovsk region. VE for two doses of measles vaccine was 93.1%, providing insufficient population immunity for measles elimination. An additional dose of measles vaccine for these age-cohorts is required if Ukraine is to achieve measles elimination. Other republics of the former Soviet Union also need to consider a supplemental dose of measles vaccine for older age groups identified epidemiologically to be at increased risk for measles even though individuals may have already received two doses.

Comparative seroepidemiology of diphtheria in six European countries and Israel

Serological surveys for diphtheria were conducted in six European countries including Czech Republic, Hungary, Ireland, Latvia, Luxembourg, Slovakia and one country outside Europe, Israel. For each country, a nationally representative population sample was collected across the entire age range and was tested for antibodies to diphtheria toxin. Although each national laboratory used its preferred assay, the results were all standardized to those of the in vitro neutralization test and expressed in international units (IU) which allowed comparative analyses to be performed. The results showed that increasing age is related to a gradual increase in seronegative subjects (<0·01 IU/ml of diphtheria antitoxin antibodies). This may reflect waning immunity following childhood vaccination without repeated booster vaccinations in adults. Differences in seronegativity were also found according to gender. In subjects aged 1-19 years, geometric mean titres of antitoxin are clearly related to the different vaccination schedules used in the participating countries. Although clinical disease remains rare, the susceptibility to diphtheria observed in these serosurveys highlights the importance of strengthened surveillance.

Bio-behavioural HIV and STI surveillance among men who have sex with men in Europe: the Sialon II protocols

BackgroundGlobally, the HIV epidemic continues to represent a pressing public health issue in Europe and elsewhere. There is an emerging and progressively urgent need to harmonise HIV and STI behavioural surveillance among MSM across European countries through the adoption of common indicators, as well as the development of trend analysis in order to monitor the HIV-STI epidemic over time. The Sialon II project protocols have been elaborated for the purpose of implementing a large-scale bio-behavioural survey among MSM in Europe in line with a Second Generation Surveillance System (SGSS) approach.Methods/DesignSialon II is a multi-centre biological and behavioural cross-sectional survey carried out across 13 European countries (Belgium, Bulgaria, Germany, Italy, Lithuania, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, and the UK) in community settings. A total of 4,966 MSM were enrolled in the study (3,661 participants in the TLS survey, 1,305 participants in the RDS survey). Three distinct components are foreseen in the study protocols: first, a preliminary formative research in each participating country. Second, collection of primary data using two sampling methods designed specifically for ‘hard-to-reach’ populations, namely Time Location Sampling (TLS) and Respondent Driven Sampling (RDS). Third, implementation of a targeted HIV/STI prevention campaign in the broader context of the data collection.DiscussionThrough the implementation of combined and targeted prevention complemented by meaningful surveillance among MSM, Sialon II represents a unique opportunity to pilot a bio-behavioural survey in community settings in line with the SGSS approach in a large number of EU countries. Data generated through this survey will not only provide a valuable snapshot of the HIV epidemic in MSM but will also offer an important trend analysis of the epidemiology of HIV and other STIs over time across Europe. Therefore, the Sialon II protocol and findings are likely to contribute significantly to increasing the comparability of data in EU countries through the use of common indicators and in contributing to the development of effective public health strategies and policies in areas of high need.

Sexual and testing behaviour associated with Chlamydia trachomatis infection: a cohort study in an STI clinic in Sweden

Background Genital chlamydia infection (chlamydia) is the most commonly reported sexually transmitted infection (STI) in Sweden. To guide prevention needs, we aimed to investigate factors associated with chlamydia. Methods A cohort of visitors aged 20–40 years at an urban STI clinic in Sweden was recruited. Behavioural data were collected using a self-administered questionnaire. Self-sampled specimens were tested for chlamydia by a DNA amplification assay. Statistically significant (p<0.05) and epidemiologically relevant covariates were entered in a multivariate Poisson model adjusted for potential confounders (age and gender). Backward stepwise elimination produced a final model. Multiple imputation was used to account for missing values. Results Out of 2814 respondents, 1436 were men with a chlamydia positivity rate of 12.6% vs 8.9% in women. Lifetime testing for chlamydia and HIV was high (82% and 60%, respectively). Factors significantly associated with chlamydia were: 20–24 years old (adjusted risk ratio (ARR)=2.10, 95% CI 1.21 to 3.65); testing reason: contact with a chlamydia case (ARR=6.55, 95% CI 4.77 to 8.98) and having symptoms (ARR=2.19, 95% CI 1.48 to 3.24); 6–10 sexual partners (ARR=1.53, 95% CI 1.06 to 2.21); last sexual activity ‘vaginal sex and oral sex and anal sex and petting’ (ARR=1.84, 95% CI 1.09 to 3.10); alcohol use before sex (ARR=1.98, 95% CI 1.10 to 3.57); men with symptoms (ARR=2.09, 95% CI 1.38 to 3.18); tested for chlamydia (ARR=0.72, 95% CI 0.55 to 0.94). Conclusions Risk factors associated with chlamydia were consistent with previous reports in similar settings and suggest no major changes over time. Increased risk for chlamydia infection associated with high-risk behaviour (eg, alcohol use, increased number of sexual partners) supports the need for behavioural interventions in this population such as promotion of safer sex behaviour (condom use) and testing.

A case-control study of risk factors for urinary acquisition of Klebsiella pneumoniae producing CTX-M-15 in an outbreak situation in Sweden.

Abstract A retrospective case–control study was initiated at Uppsala University Hospital in 2006 during a major outbreak caused by a Klebsiella pneumoniae strain producing CTX-M-15. To identify risk factors associated with acquisition of the outbreak strain in the urinary tract, 52 case patients with a urine culture positive for the outbreak strain between 1 May and 31 December 2005 were enrolled. Case patients were matched 1:2 with concurrently hospitalized control patients with significant growth of susceptible Escherichia coli in a urine sample. Conditional logistic regression analyses identified hospital stay ≥9 days (odds ratio (OR) 18.8, 95% confidence interval (CI) 5.74–61.2), nasogastric feeding tube (OR 18.0, 95% CI 2.28–142) and diarrhoea (OR 9.62, 95% CI 3.30–28.1) as risk factors with high ORs. The odds of previous use of cephalosporins were 7.58 (95% CI 3.13–18.4) times higher in case patients compared with the controls. Several multivariable models were evaluated to reduce bias from confounding. These models identified prolonged period of hospitalization, diarrhoea, malignancy and antibiotic use as the most important risk factors for acquisition of the outbreak strain, factors that are often found in elderly patients with a poor functional status.

Socio-demographic Characteristics, Sexual and Test-Seeking Behaviours Amongst Men Who have Sex with Both Men and Women: Results from a Bio-behavioural Survey in 13 European Cities

Within the MSM population, men who have sex with both men and women (MSMW) are identified as a high-risk group both worldwide and in Europe. In a multi-centred bio-behavioural cross-sectional study, we aimed to assess the relationship(s) between socio-demographic factors, stigma, sexual behavioural patterns, test seeking behaviour and sero-status amongst MSMW. A multi-level analysis was conducted to identify factors associated with being MSMW versus Men who have Sex with Men Only (MSMO). A total of 4901 MSM were enrolled across the 13 study sites. Participants were categorised as MSMW in the 12.64% of the cases. Factors such as educational status, perceived homonegativity, testing facilities knowledge and HIV testing lifetime seem to be relevant factors when characterising the MSMW group. The results highlight the vulnerability of MSMW and the wide spectrum of risky behavioural and psycho-social patterns, particularly in terms of HIV testing, ‘outness’, and perceived stigma.ResumenLos Hombres que tienen Sexo con Hombres y Mujeres (HSHM) son un grupo de población de alto riesgo dentro de los HSH. Evaluar la relación entre factores socio-demográficos, estigma, patrones de conducta sexual y de búsqueda de la prueba y el estado serológico de los HSHM. Estudio bio-conductual multicéntrico transversal. Análisis multinivel para identificar factores asociados con ser HSHM respecto a los Hombres que Sólo tienen Sexo con Hombres. Se reclutaron 4.901 HSH en 13 ciudades, siendo un 12,64% HSHM. El nivel educativo, la homonegatividad percibida, el conocimiento de los lugares de realización de la prueba y la prueba del VIH alguna vez son factores relevantes para caracterizar los HSHM. Los resultados subrayan la vulnerabilidad de los HSHM y la diversidad de conductas y patrones psicosociales de riesgo, particularmente en términos de la prueba del VIH, visibilidad de la identidad sexual y estigma percibido.

Prevalence of drug use during sex amongst MSM in Europe: Results from a multi-site bio-behavioural survey

BACKGROUND Substance use has been consistently reported to be more prevalent amongst Men who have Sex with Men (MSM) compared to the general population. Substance use, in particular polydrug use, has been found to be influenced by social and contextual factors and to increase the risk of unprotected intercourse among MSM. The objective of this analysis was to investigate the prevalence and predictors of drug use during a sexual encounter and to identify specific prevention needs. METHODS/DESIGN A multi-site bio-behavioural cross-sectional survey was implemented in 13 European cities, targeting MSM and using Time-Location Sampling and Respondent-Driven Sampling methods Multivariable multi-level logistic random-intercept model (random effect of study site) was estimated to identify factors associated with the use of alcohol, cannabis, party drugs, sexual performance enhancement drugs and chemsex drugs. RESULTS Overall, 1261 (30.0%) participants reported drug use, and 436 of 3706 (11.8%) reported the use of two or more drugs during their last sexual encounter. By drug class, 966 (23.0%) reported using sexual performance enhancement drugs, 353 (8.4%) - party drugs, and 142 (3.4%) the use of chemsex drugs. Respondents who reported drug use were more frequently diagnosed with HIV (10.5% vs. 3.9%) before and with other STIs during the 12 months prior to the study (16.7% vs. 9.2%). The use of all the analysed substances was significantly associated with sexual encounter with more than one partner. DISCUSSION Substance and polydrug use during sexual encounters occurred amongst sampled MSM across Europe although varying greatly between study sites. Different local social norms within MSM communities may be important contextual drivers of drug use, highlighting the need for innovative and multi-faceted prevention measures to reduce HIV/STI risk in the context of drug use.

Travel-associated gonorrhoea in four Nordic countries, 2008 to 2013

Travel may be associated with a higher risk of gonorrhoea and infection by antibiotic-resistant strains. The objective of this study was to estimate the risk for gonorrhoea among travellers from four Nordic European countries using surveillance data and to identify at-risk travellers to help target interventions. We retrieved gonorrhoea surveillance data from Denmark, Finland, Norway and Sweden and tourism denominator data from the Statistical Office of the European Union. A travel-associated case of gonorrhoea was defined as one for which the reported country of infection differed from the reporting country. During 2008−2013, the four countries reported 3,224 travel-associated gonorrhoea cases, of which 53% were among individuals below 35 years of age. The overall risk associated with travel abroad was 2.4 cases per million nights abroad. The highest risk was observed with travel to Asia (9.4). Cases more likely to be reported as travel-associated were: males, heterosexuals of both sexes, people older than 65 years, and foreign-born individuals. More effective interventions targeting young adults and other at-risk groups are needed. The use of travel-planning websites and social media should be explored further.