Cryptococcosis is not a commonly diagnosed disease. Records of its occurrence in Britain are virtually non-existent before 1945. when the Mycological Reference Laboratory (MRL) of the Public Health Laboratory Service was first established

The predominance of coagulase-negative staphylococci as normal skin flora is thought to be a factor in their association with episodes of peritonitis in patients undergoing continuous ambulatory peritoneal dialysis. We investigated the prevalence of peritonitis-associated strains on the skin of 28 patients undergoing peritoneal dialysis. Coagulase-negative staphylococci were the most frequently isolated organisms. comprising 47% of peritoncal dialysis fluid isolates and 59% of body site isolates. A total of 142 coagulase-negative staphylococci were speciated. tested for their antimicrobial sensitivity and slime production. and identified by phage typing and plasmid-profile analysis. Staphylococcus epidermidis was the most commonly identified species from both peritoncal dialysis fluid (73%) and body sites (53%). Multiple antibiotic resistance was common, and the greater proportion of isolates were resistant to methicillin: 63·6% of peritoncal dialysis fluid isolates and 61·7% of body-site isolates.isolates. S. haemolyticus isolates were significantly more resistant to methicillin than other species. By phage typing and plasmid-profile analysis it was shown that peritonitis was rarely caused by skincolonizing strains. In only 3 of 14 patients were peritonitis-associated strains isolated as skin colonizers, and no patients developed peritonitis due to organisms previously isolated as skin colonizers.

A collection of 308 clinical isolates of β-haemolytic Lancefield group C streptococci was assembled from laboratories in England. Nigeria and New Zealand. Of these, 276 isolates were Streptococcus equisimilis. 23 S. milleri and nine S. zooepidemicus. Isolates of S. equisimilis in the African collection, though few, gave higher rates of lactose and raffinose fermentation, aesculin hydrolysis and positive α-galactosidase reactions than those from elsewhere. Erythromycin resistance was found in 1·9% of the English isolates of S. equisimilis.Strains from superficial infections accounted for 88 % of the collection and were most commonly isolated from the upper respiratory tract, skin or wounds. Amongst the 36 patients yielding isolates from deep sites S. equisimilis was found in septicaemia, cellulitis, abscess, peritonitis, septic arthritis, pneumonia, mycotic aneurysm and acute epiglottitis. S. milleri was found in abdominal abscesses, peritonitis, pleural empyema and osteomyelitis and S. zooepidemicus was found in septicaemia, pneumonia, meningitis and septic arthritis. Within the collection an unselected general catchment of 214 isolates of group C streptococci from the laboratories in Yorkshire showed the following species: from 199 superficial infections 94% S. equisimilis. 5% S. milleri and 1% S. zooepidemicus and 15 patients withdeeper, more agressive infections 67, 27 and 6·7% of these species respectively.

Clinical features, treatment and outcome were assessed retrospectively by means of a questionnaire in 174 patients in general practice whose vaginal swabs yielded bcta-haemolytic streptococci. These were compared with 96 patients whose swabs yielded no recognized microbial pathogens. Patients with group B streptococci did not differ in any of these parameters from the control group, but those with group A streptococci were more likely to have vaginal soreness, a purulent discharge. and to respond to anti-streptococcal antibiotics. Implications for laboratory reporting are discussed.

It has been proposed that inhibitory substances produced by viridans streptococci colonizing the upper respiratory tract aid in cradication of established group A streptococcal colonization of that site. We studied the prevalence of inhibitory-substance producing strains of Streptococcus salivarius in throat cultures from three groups of children: 16 children with persistently positive throat cultures for group A streptococci despite receiving recommended therapeutic courses of antibiotics (group I). 26 children from whom group A streptococci were eradicated from the upper respirator tract by antibiotic therapy (group II). and 18 children who never harboured group A streptococci in their upper respiratory tract during the study period (group Ill). An vitro deferred antagonism method was employed to detect inhibitory substances: 5233 strains of S. salivarius were examined. Strains of S. salivarius producing inhibitory substances were isolated from 76−88% of the children in each group on at least one occasion.However, only a small percentage of subjects in each group harboured strains producing these substances in every throat culture. The mean total percentage of S. salivarius strains producing inhibitory substances was 21·8% in children in group 1·22.4 % in children in group II. and 16.4% in children in group III: these percentages were not statistically different (P > 0·1). In this study, we could not confirm a significant role for inhibitory substances produced byS. salivarius in the eradication of group A streptococci from the upper respiratory tract of colonized individuals.

A group of 150 Staphylococcus saprophyticus strains isolated from urinary tract infections in women were included in this study. Antimicrobial susceptibility tests showed that these isolates were sensitive to most antimicrobial agents. All strains were sensitive to penicillin. cephalothin. gentamicin. kanamvcin. trimethoprim and nitrofurantoin. Resistance to tetracycline was present in 10·6% of the strains. to chioramphenicol in 4 % to erythromycin in 1·3% and to streptomvcin in 1·3% All strains were resistant to cadmium chloride as well as to novobioein and nalidixic acid. Plasmid analysis showed that 8·2 % of the strains harboured plasmids, some of them with complex plasmid profiles.

One hundred and twenty-five Shigella flexneri strains, isolated during January-December 1984, at the Dhaka treatment centre of the International Centre for Diarrhoeal Disease Research, Bangladesh, were serotyped using absorbed rabbit antisera specific for all type-and group-factor antigens, as well as a group of ten mouse and rat monoclonal antibodies. Electropherotypes of the plasmid deoxyribonucleic acid (DNA) were also determined. S. flexneri 2a was the predominant serotype followed by 3b, 1a, and 2b.The recently described E1037 antigen was also found in three strains of S. flexneri serotype 6. Electropherotyping of the plasmid DNA showed that three plasmids of approximately 140. 2·7. and 2 megadalton (MDa) were present, respectively, in 97, 97 and 94% of the 125 strains. Additional plasmids of various other sizes were also present in different serotypes except in serotype 2a. The additional plasmids again appeared to be specific for that particular serotype. For example, all 12 strains of S. flexneri 2b harboured an additional plasmid of approximately 1 MDa. Thus, electropherotyping of plasmid DNA of different serotypes of S. flexneri might be useful to differentiate S. flexneri from other species of Shigella and in identifying different serotypes of S. flexneri. Therefore, the common plasmids, plus the additional plasmids. could be used to identify epidemic, as well as sporadic, subclones of S. flexneri strains.

One hundred and fifty-three water samples from rural Nicaragua were examined for the presence of faecal coliforms during both wet and dry periods. A linear model as fitted by analysis of covariance with the logarithm of the faecal coliform count as the dependant variable. As expected, traditional water sources were grossly contaminated at all times whereas piped water sources were much cleaner. Hand-dug protected wells had significantly higher levels of faecal contamination than unprotected riverside wells and springs during the dry season. The possible reasons for this unexpected finding are discussed. A close association between rainfall and faecal contamination was demonstrated but the effect of rainfall depended on the type of water source. An association between water quality and the size of the community served by the source was also detected. The finding that stored water was usually more contaminated than fresh water samples is consistent with the results from other studies. Since it is unusual for water quality to be inversely correlated wth accessibility, this study site would be suitable for investigating the relative importance of water-borne versus waterwashed transmission mechanisms in childhood diarrhoea.

During 1986 and 1987, faecal samples from patients with haemorrhagie colitis (HC) or haemolytic-uraemic syndrome (HUS) were examined for evidence of infection by verotoxin-producing Escherichia coli (VTEC). During the 2-year period VTEC infections were found in 31 (78%) of 40 patients initially presenting with HC, and in 5 (63%) of 8 patients initially presenting with HUS, VTEC were found in only 2 (0·9%) of 229 age and sex matched control patients with acute non-bloody diarrhoea. All but one VTEC belonged to E. coli serogroup O 157. During 1987 this serogroup was isolated from 2 (1%) of 207 samples of faeces taken from cattle arriving at a Sheffield abattoir, indicating a possible source of these infections for man. We are unaware of previous reports of isolation of this organism from cattle in England.

Necrobacillosis is caused by Fusobacterium necrophorum (FN), but other organisms are often present in the lesions. Their possible role was studied in experiments made with a virulent FN strain which, by itself, produced fatal necrobacillosis in mice provided that large doses ( > 106 organisms, subcutaneously) were given. Mice were inoculated subcutaneously with FN suspended in sub-lethal doses (0·1 ml) of undiluted or diluted broth cultures of other bacteria. Undiluted culture of a strain of Escherichia coli reduced the infective dose of FX to < 10 organisms: in the necrobacillosis lesions that developed, fusobacteria greatly outnumbered E. coli. A heat-killed preparation or sterile filtrate of E. coli culture had little if any effect on FN. Citrobacter freundii and comparativelv small numbers of Corynebacterium (Actinomyces) pyogenes produced effects similar to that of E. coli. An α-haemolvtic streptococcus. Pseudomonas aeruginosa. Bacteroides fragilis and Fusobacterium nudeatum also enhanced the infectivity of FN. though less strikingly than E. coli. FN increased the persistence in vivo of the α-haemolytic streptococcus and B. fragilis, and enabled the latter to multiply profusely.

Differentiation of Salmonella enteritidis by plasmid profile typing has been compared to differentiation by phage typing. Examination of the type strains of the 27 S. enteritidis phage types showed that only 11 profile patterns could be identified. Moreover, two profile patterns were found in 15 of the type strains, including those of the two most common phage types in Britain, types 4 and 8. On this basis, plasmid profile typing is not as sensitive as phage typing for the primary subdivision of S. enteritidis.

When differentiation of 534 strains of the 27 phage types was attempted using plasmid profiles, variation in pattern suitable for epidemiologieal subdivision was found in 13 phage types and there were 9 profile patterns in strains of phage type 4. Plasmid profile typing can, therefore, be regarded as an effective adjunct to phage typing for the subdivision of S. enteritidis

Mice, birds (chicks, quail) and fish (rudd, goldfish) killed shortly after receiving 1300–2000 spores of Clostridium botulinum per os were incubated, usually at 23 °C for 7 days. A 10% (w/v) homogenate of each rotting carcass was then prepared, sterilized by membrane filtration, and assayed for toxin.

In mouse carcasses a type C strain of C. botulinum usually produced > 2 × 105 mouse intraperitoneal LD/g; in fish carcasses it usually produced less - often much less - than 2 × 104 LD/g. Avian carcasses appeared to be intermediate between those of mice and fish in their ability to support toxigenesis. A type E strain of C. botulinum, unlike type C. produced toxin equally well in fish and mouse carrion, usually at a concentration of between 2 × 104 and 2 × 105 LD/g.

A mathematical model has been developed which allows estimation of the epidemiological and economic effects of different tetanus vaccination strategies. The model was used to simulate the epidemiology of tetanus in italy from 1955 to 1982, and then applied to a district of Tuscany by utilizing data obtained from a seroepidemiological survey carried out in the same area. For this district we simulated vaccination programmes designed to reach, within 1 or 10 years, coverages of 60 or 90% of the population aged over 10 years who had not been exposed to the neonatal vaccination programme. The most effective strategy, from both the epidemiological and economic point of view, seems to be 90% coverage reached in 1 year's time. Benefits would be increased by improving the reliability of vaccinal anamnesis.

A simultaneous study of cockroach (Supella supellectilium) distribution and of associated carried bacterial flora has been made in the main hospital in Rennes (France).

Wild cockroaches carry a high number of bacterial species that can be related to the normal environmental flora and a contaminant flora acquired from particular environments. The diversity of carried bacterial species reveals a proximity factor between continguous floors of the building which leads us to suppose that cockroaches are able to forage from one floor to the other.

The chemical disinfection of virus-contaminated non-porous inanimate surfaces was investigated using coxsackievirus B3, adenovirus type 5, parainfluenzavirus type 3 and coronavirus 229E as representatives of important nosocomial viral pathogens. A 10 µl amount of the test virus, suspended in either faeces or mucin, was placed onto each stainless steel disk (about 1 cm in diameter) and the inoculum allowed to dry for 1 h under ambient conditions. Sixteen disinfectant formulations were selected for this study based on the findings of an earlier investigation with a human rotavirus.After 1 min exposure to 20 µl of the disinfectant, the virus from the disks was immediately eluted into tryptose phosphate broth and plaque assayed. Using an efficacy criterion of a 3 log10 or greater reduction in virus infectivity titre and irrespective of the virus suspending medium, only the following five disinfectants proved to be effective against all the four viruses tested: (1) 2% glutaraldehyde normally used as an instrument soak.(2) a strongly alkaline mixture of 0·5% sodium o-benzyl-p-chlorophenate and 0·6% sodium lauryl sulphate, generally used as a domestic disinfectant cleaner for hard surfaces, (3) a 0·04% solution of a quaternary ammonium compound containing 7% hydrochloric acid, which is the basis of many toilet bowl cleaners. (4) chloraminc T at a minimum free chlorine level of 3000 p.p.m. and (5) sodium hypochlorite at a minimum free chlorine concentration of 5000 p.p.m. Of those chemicals suitable for use as topical antiseptics, 70% ethanol alone or products containing at least 70% ethanol were ineffective only against coxsackievirus B3. These results emphasize the care needed in selecting chemical disinfectants for routine use in infection control.

A detailed study was made in 1983–5 in three villages in Mehinji district in the African swine fever (ASF) enzootic area of Malawi, following an outbreak of ASF which affected all three villages.

Ticks of the Ornithodoros moubata complex were collected from both pig sties and houses shortly after the outbreak, and approximately 24% contained ASF virus. The proportion of ticks infected did not differ significantly in the three villages, or more surprisingly in different types of premises, and was equivalent in all stages of ticks. The proportion infected decreased with the passage of time, but infected ticks were still present in all three villages 8 months after the outbreak,some with high titres of virus.

The proportion of seropositive pigs in the three villages approached 100% following the outbreak, with many apparently healthy pigs being seropositive. It is suggested that Malawian isolates of ASF virus may be less virulent in African than European breeds of domestic pig.

Monoclonal antibodies specific for rotavirus subgroup 1 (SG1) and subgroup 2 (SG2) were used to analyse by enzyme immunoassay (EIA) the subgroups of human rotavirus isolates obtained from three different parts of India during the period September 1985 to July 1987. We identified one isolate which failed to react with either SG1 or SG2 specific monoclonal antibodies, although it reacted well with a monoclonal antibody specific for group A rotaviruses. This finding suggests that it belongs to a new rotavirus subgroup. Further, another isolate was found to belong to SG1 although it had a ‘long’ electropherotype.

We have analysed data on respiratory syneytial (RS) and parainfiuenza type 3 (PF3) viruses reported to the Communicable Disease Surveillance Centre. London, over the period 1978–87. These confirm the annual winter epidemic of RS virus and show that, in England and Wales, PF3 is a summer infection with regular yearly epidemics.

Cryptosporidium oocysts were observed in the stools of 9 (7·2%) of 124 Italian children with diarrhoea, examined during the period 1 January—31 December 1984. In two children, the parasite was associated with other enteric pathogens. The duration of diarrhoea was 2–30 days, with a median of 6 days. In all cases the infection was self limiting. The mean age of the Cryptosporidium-positive children was 34 months, and all cases occurred in the warm season. Cryptosporidium was found to be the third most common enteric pathogen after rotavirus and Salmonella spp.

Epidem. Inf. 102 (1989), 33

N. Bornstein. Marmet. M. Surgot, M. Nowicki, A. Arslan, J. Esteve and J. Fleurette

Exposure to Legionellaceae at a hot spring spa: a prospective clinical and serological study

Table 1. penultimate line: ‘≤ L. pneumophila’ should read

‘≥ 128 L. pneumophila’

line 14:‘ 103–105 colony forming units (c.f.u.).’ should read ‘ 103–105 colony forming units/1.’