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The WHO Consensus Document on the epidemiology of the SARS epidemic in 2003, included a report on a concentrated outbreak in one Hong Kong housing block which was considered a ‘super-spreading event’. The WHO report conjectured that the sanitary plumbing system was one transmission route for the virus. Empty U-traps allowed the aerosolised virus to enter households from the sewerage system. No biological evidence was presented. This research reports evidence that pathogens can be aerosolised and transported on airstreams within sanitary plumbing systems and enter buildings via empty U-traps. A sanitary plumbing system was built, representing two floors of a building, with simulated toilet flushes on the lower floor and a sterile chamber with extractor fan on the floor above. Cultures of a model organism, Pseudomonas putida at 106–109 cfu ml-1 in 0·85% NaCl were flushed into the system in volumes of 6 to 20 litres to represent single or multiple toilet flushes. Air and surface samples were cultured on agar plates and assessed qualitatively and semi-quantitatively. Flushing from a toilet into a sanitary plumbing system generated enough turbulence to aerosolise pathogens. Typical sanitary plumbing system airflows (between 20–30 ls-1) were sufficient to carry aerosolised pathogens between different floors of a building. Empty U-traps allowed aerosolised pathogens to enter the chamber, encouraging cross-transmission. All parts of the system were found to be contaminated post-flush. Empty U-traps have been observed in many buildings and a risk assessment indicates the potential for high risk cross-transmission under defect conditions in buildings with high pathogen loading such as hospitals. Under defective conditions (which are not uncommon) aerosolised pathogens can be carried on the airflows within sanitary plumbing systems. Our findings show that greater consideration should be given to this mode of pathogen transmission.

The results of two studies are reported examining the utility of a pictorial modified Stroop task in the assessment of sexual interest in a sample of non offending participants and of sexual offenders against children. A mixed factorial design was adopted for both. Nine gay and twelve straight participants took part in the first study which found that participants typically had attentional bias on the pictorial modified Stroop task that was in line with their stated sexual interests. Twenty four sexual offenders against children and twenty four control participants took part in the second study. Again results indicated that the task was tapping into the participants' stated sexual interests. Furthermore extrafamilial offenders and offenders with an admitted sexual interest in children demonstrated the greatest mean bias for child stimuli relative to adult stimuli. A cautious interpretation of the results was recommended, given the sample size in the study, the heterogeneity of the sample, differences in cognitive speed among offenders and controls and other methodological caveats.

A 23-year-old female presented with severe Cushing's syndrome in the 23rd week of pregnancy. Investigations showed plasma cortisol 770 nmol/l (08.00 h) and 850 nmol/l (23.00 h); plasma ACTH was 10 ng/l (08.00 h) and 27 ng/l (23.00 h); urinary free cortisol excretion was 2460 nmol/24 h. Dexamethasone 2 mg 6-hourly for 48 h suppressed the 08.00 h plasma cortisol only to 680 nmol/l. Abdominal C.T. scan showed a right adrenal adenoma. The patient was treated with metyrapone and a good clinical improvement ensued. Plasma cortisol was reduced to 300-500 nmol/l. Depsite ultrasonographic evidence of normal fetal growth, urinary oestriol excretion was markedly deficient. Prior to the spontaneous onset of labour, there was a marked rise in plasma cortisol despite continuous metyrapone treatment. A normal female infant was born at 37 weeks' gestation. The maternal adrenal adenoma was subsequently removed. The deficiency of oestriol synthesis during the pregnancy may be explained by metyrapone-induced inhibition of C19-hydroxylation.