Use of gender distribution in routine surveillance data to detect potential transmission of gastrointestinal infections among men who have sex with men in England.

Detecting gastrointestinal (GI) infection transmission among men who have sex with men (MSM) in England is complicated by a lack of routine sexual behavioural data. We investigated whether gender distributions might generate signals for increased transmission of GI pathogens among MSM. We examined the percentage male of laboratory-confirmed patient-episodes for patients with no known travel history for 10 GI infections of public health interest in England between 2003 and 2013, stratified by age and region. An adult male excess was observed for Shigella spp. (annual maximum 71% male); most pronounced for those aged 25-49 years and living in London, Brighton and Manchester. An adult male excess was observed every year for Entamoeba histolytica (range 59.8-76.1% male), Giardia (53.1-57.6%) and Campylobacter (52.1-53.5%) and for a minority of years for hepatitis A (max. 69.8%) and typhoidal salmonella (max. 65.7%). This approach generated a signal for excess male episodes for six GI pathogens, including a characterised outbreak of Shigella among MSM. Stratified analyses by geography and age group were consistent with MSM transmission for Shigella. Optimisation and routine application of this technique by public health authorities elsewhere might help identify potential GI infection outbreaks due to sexual transmission among MSM, for further investigation.

Intensified shigellosis epidemic associated with sexual transmission in men who have sex with men--Shigella flexneri and S. sonnei in England, 2004 to end of February 2015.

Surveillance data suggest an intensification of the shigellosis epidemic associated with sexual transmissionin men who have sex with men (MSM) in England with separate introductions into the population. In 2014, sexual transmission between MSM might have accounted for 97%, 89%, and 43% of non-travel associated Shigella flexneri 3a and S. flexneri 2a, andS. sonnei diagnoses. Clinicians should sensitively ascertain sexual history for men with enteric infections to facilitate prompt diagnosis and appropriate management.

Identification of verocytotoxin-producing Escherichia coli O117:H7 in men who have sex with men, England, November 2013 to August 2014.

Between November 2013 and August 2014, nine cases of verocytotoxin-producing Escherichia coli O117:H7 VT1 were confirmed in adult men. Further investigation using semi-structured interviews revealed that eight cases were United Kingdom (UK)-born men who have sex with men (MSM) who had sexually acquired infection in the UK. Most were HIV-positive with high numbers of sexual partners. This behavioural profile resembles that associated with the recent rapid increase in other sexually acquired infections in MSM.

The epidemiology of gonorrhoea in London: a Bayesian spatial modelling approach.

Data obtained from genitourinary medicine clinics through a comprehensive surveillance system were used in a Bayesian mixed-effects Poisson regression model to explore socio-demographic individual and ecological risk factors for gonorrhoea in London, as well as its spatial clustering. The spatial analysis was performed at the Middle-layer Super Output Area level (median population size 7200). A total of 12452 individuals were diagnosed during the 2-year study period (2009-2010). The study confirmed the presence of 'core areas' of high incidence, and identified 'core' high-risk groups, in particular young adults (16-29 years), males, black Caribbeans and more deprived areas. The individual (age, sex, ethnicity) and area-level (deprivation, teenage pregnancies, students) model covariates accounted for 48% of the variance. Most of the remaining variance was explained by the spatial effect, thus capturing other spatially distributed factors associated with gonorrhoea, such as local sexual networks. These findings will be useful in identifying areas for targeted interventions, such as STI testing and health promotion.

Outbreak investigation and case-control study: penta-resistant Salmonella Typhimurium DT104 associated with biltong in London in 2008.

In August 2008 an outbreak of Salmonella Typhimurium DT104 occurred in South West London. Sixteen cases were identified with a particular multilocus variable number tandem repeat analysis (MLVA) pattern. In a matched case-control study 14 primary cases were included. These were defined as individuals with gastrointestinal symptoms and Salmonella Typhimurium DT104 isolated from a stool specimen, with a characteristic antibiotic resistance profile and MLVA pattern, and diagnosed in a local laboratory. Four controls per case were matched on age, gender and area of residence. Cases were 26 times more likely than controls to have eaten beef biltong, a South African speciality meat product (odds ratio 25·83, 95% confidence interval 4·92­135·59, P < 0·01). Although environmental investigation failed to identify Salmonella in the food product we conclude that beef biltong consumption led to this outbreak. This conclusion has importance in informing the ongoing risk assessment relating to uncontrolled foodstuffs.

A European outbreak of Salmonella enterica serotype Typhimurium definitive phage type 204b in 2000.

OBJECTIVE: To describe the clinical, epidemiologic and microbiological features of a large outbreak of infection with a multiresistant Salmonella enterica serotype Typhimurium definitive type DT204b infection involving at least 392 people in five European countries. METHODS: Icelandic public-health doctors responded to a report on an Internet news site of an outbreak of infection with a multiresistant strain of Typhimurium DT104 in England by contacting the Public Health Laboratory Service (PHLS) Communicable Disease Surveillance Centre (CDSC). An international alert was sent out through Enter-net. All strains from England & Wales, The Netherlands, Scotland and Germany, and 17 of the outbreak isolates from Iceland, were phage-typed, screened for antimicrobial resistance, and subjected to molecular typing. Hypothesis-generating interviews were conducted, followed by case-control studies performed in Iceland and England. RESULTS: Isolates from cases in Iceland, England and Wales, The Netherlands, Scotland and Germany were identified as Typhimurium DT204b. The antimicrobial resistance pattern was ACGNeKSSuTTmNxCpL. All strains tested displayed an identical plasmid profile. Strains from five cases in England & Wales and five cases in Iceland possessed identical pulsed-field profiles. Although a common source was suspected, only Iceland implicated imported lettuce as a vehicle, with an analytic epidemiologic study (OR = 40.8; P = 0.005; 95% CI 2.7-3175). CONCLUSION: The identification of international outbreaks, necessary for investigation and control, can be facilitated by standardized phage-typing techniques, the electronic transfer of molecular typing patterns, formal and informal links established through international surveillance networks, and the early reporting of national outbreaks to such networks.

West Nile virus and the threat to the UK.

West Nile virus (WNV) is an RNA virus and a member of the Flaviviridae family. The recent geographical expansion of WNV into areas where no activity had been previously reported has been highlighted by the detection of WNV in North America. There is also a recent trend for more numerous and serious outbreaks in Eurasia. The main hosts are birds and the principle vectors are mosquitoes, usually of the genus Culex. Although most infected people do not become symptomatic, severe diseases such as encephalitis and, less commonly, aseptic meningitis may occur, more frequently in the elderly. The public can be protected by giving advice on the avoidance of mosquito bites and by the implementation of ecological surveillance and measures to reduce the mosquito population. While a few human cases have been identified in returning travellers, WNV has not been reported in any animal or bird in the UK. However, this may simply indicate that the diagnosis has not been sought. Potential avian hosts and mosquito vectors of WNV are present in the UK and birds migrate to the UK from areas of endemic WNV activity. However, the population density of mosquitoes is relatively low and therefore the risk of WNV being transmitted in the UK is thought to be low. We lack sufficient information on the ecology of the virus, and on mosquito populations, to accurately determine this risk. Clinicians are advised to consider WNV as a differential diagnosis, especially in patients over 50 years old with a clinical picture of viral encephalitis or aseptic meningitis presenting in the summer months.

London--the next battleground for syphilis?

Recent outbreaks of infectious syphilis across England raise concerns about the possibility of similar occurrences in London and highlight the inability of routine surveillance to detect outbreaks in a timely fashion. A rapid assessment exercise involving a cross-sectional survey of all London genitourinary medicine (GUM) clinics was therefore undertaken in April 2001, to confirm recent reports of infectious syphilis and the associated demographic and behavioural risk factors. Between 1999 and 2000, the number of diagnoses of infectious syphilis in London rose by 41% from 154 to 217. Largest rises were seen in homosexual males (38 to 67 diagnoses), and this trend persisted into the 1st quarter of 2001. Nearly half of the male homosexual cases where HIV status was known were HIV positive.