In 2000, an unusual increase of morbidity and mortality among illegal injecting drug users in the UK and Ireland was reported and Clostridium novyi was identified as the likely source of the serious infection, although infections due to C. botulinum and Bacillus cereus were also reported. Because heroin was a possibile source of infection, this study investigated the microflora of heroin samples seized in England during 2000 and 2002. Two methods were developed for the examination of the microflora of heroin. The first consisted of suspension of the drug in maximum recovery diluent (MRD) which was inoculated directly into Clostridium Botulinum Isolation Cooked Meat Broth (CBI). The second method rendered the heroin soluble in citric acid, concentrated particulate material (and bacterial cells) by filtration and removed heroin residues by washing with citric acid and phosphate-buffered saline before placing the filter in CBI broth. Duplicate CBI broths from both methods were incubated without heating and after heating at 608C for 30 min. Subcultures were made after incubation for 7 and 14 days on to eight different solid media. The methods were evaluated with heroin samples spiked with either C. botulinum or C. novyi spore suspensions; recovery of 10 spores in the original sample was demonstrated. Fifty-eight heroin samples were tested by citric acid solubilisation and 34 by the MRD suspension technique. Fifteen different grampositive species of four genera were recognised. No fungi were isolated. Aerobic endospore-forming bacteria (Bacillus spp. and Paenibacillus macerans) were the predominant microflora isolated and at least one species was isolated from each sample. B. cereus was the most common species and was isolated from 95% of all samples, with B. licheniformis isolated from 40%. Between one and five samples yielded cultures of B. coagulans, B. laterosporus, B. pumilus, B. subtilis and P. macerans. Staphylococcus spp. were isolated from 23 (40%) samples; S. warneri and S. epidermidis were the most common and were cultured from 13 (22%) and 6 (10%) samples respectively. One or two samples yielded cultures of S. aureus, S. capitis and S. haemolyticus. The remainder of the flora detected comprised two samples contaminated with C. perfringens and two samples with either C. sordellii or C. tertium. Multiple bacterial species were isolated from 43 (74%) samples, a single species from the remaining 15. In 13 samples B. cereus alone was isolated, in one B. subtilis alone and in one sample B. pumilus alone. C. botulinum and C. novyi were not isolated from any of the heroin samples. Recommendations for the optimal examination of the microflora of heroin are given.

No abstract

No abstract

The death has occurred in Liverpool of the artist, poet and public health practitioner manqué, Adrian Henri. This is a reflection on a collaboration that crossed C P Snow's two cultures, 1 which lasted almost 20 years and paid rich dividends for public health on Merseyside and way beyond.

Matters arising association is influenced by the way in which the control group is selected and in this regard we question the nature of controls studied by Jensen and colleagues. It appears that none of the asymptomatic control subjects was examined microscopically to determine the existence of urethral polymorphonuclear (PMN) leucocytes. Indeed, men with "asymptomatic" urethritis may have been included in the control group. Few investigators have compared the prevalence of mycoplasmas in men with microscopic urethritis who have no signs or symptoms with that in men without urethritis. However, Swartz et al6 found that Chlamydia trachomatis was isolated more frequently from men with asymptomatic NGU than from those without objective urethritis, suggesting that urogenital pathogens may be involved in the aetiology of this condition. In addition, it is unclear whether Jensen and colleagues examined the asymptomatic subjects clinically at enrolment. Clearly, asymptomatic men with a discharge on examination and objective urethritis ( 3 5 PMN leucocytes/high-power microscopic field) have "clinical urethritis" and should be excluded from the control group and included in the study-group. Inclusion of asymptomatic men who have objective urethritis, with or without an observable discharge, in the control group would prevent proper evaluation of negative associations.This may have influenced to some extent the significance given to M genitalium by Jensen and colleagues and biased their results against detecting an association of U urealyticum with NGU.