In 1962 the Public Health Laboratory Service (PHLS) became responsible for the Poliomyelitis Surveillance Scheme for England and Wales, which since 1970 has included the World Health Organisation (WHO) enquiry into Acute Persisting Spinal Paralysis. All the records have been kept, including those of patients who were later considered not to have had poliomyelitis. This paper reviews the cases between 1970–84 of patients normally resident in England and Wales, where the clinical features of the illness were considered by the clinician in charge to be those of poliomyelitis and in which either poliovirus was isolated or there was serological evidence of recent infection. Seventy cases met these criteria. Two patients died. A wild strain of poliovirus was isolated in 19 cases; a vaccine-like strain in 27; an intermediate strain in 5; and in 19 cases the strain was not known or there was no isolate. Eleven patients had a history of overseas travel; 17 had been vaccinated recently; and 12 had been in contact with a recent vaccinee. In the remaining 30 cases, the source of the infection was not found. Other details, including the age distribution, vaccination history and the laboratory findings are discussed.

A total of 100 tropical aquaria from six pet shops were sampled for the presence of Salmonella, Campylobacter and Aeromonas species. Eight fish tanks contained unusual serotypes of salmonella. None had been used to house terrapins. One hundred and three isolates of Aeromonas species were obtained from 98 tanks. One tank contained Plesiomonas shigelloides. No Campylobacter species were isolated. It is suggested that a tropical aquarium may constitute an infection hazard.

Twelve British isolates of leptospira belonging to the Sejroe serogroup were examined using a series of six factor sera prepared by a number of different absorption methods. Ten of the isolates were identified as Leptospira interrogans serovar hardjo and two as L. interrogans serovar saxkoebing. These isolates had previously been identified using the cross agglutination absorption method.

A molecular epidemiological study was carried out on 60 Salmonella dublin isolates identified at the Southern Italy Enterobacteriaceae Center between 1971 and 1985. These included 23 isolates from children with diarrhoea in Palermo obtained during 1984.

All isolates from the outbreak of gastroenteritis in children were resistant to chloramphenicol and streptomycin and harboured two plasmids of 50 MDa and 3 MDa molecular weight, whereas the majority of the isolates identified before 1984 were susceptible to these antibiotics and carried only a 50 MDa molecular weight plasmid. Four S. dublin strains successively identified from cattle (Palermo, Foggia, Portici) and from a child (Palermo) were shown to possess similar antibiotic resistance patterns and plasmid profiles to S. dublin isolates from the outbreak of gastroenteritis in children.

The 50 MDa plasmid was shown to be associated with virulence in mice, while it was not possible to assign any genetic function to the 3 MDa plasmid.

Some 94 strains of Ieptospires belonging to the Sejroe serogroup isolated in the British Isles were identified to the serovar level using specific factor sera.

Seventy strains were identified as Leptospira interrogans serovar hardjo, 66 from cattle, 2 from pigs and 1 each from a sheep foetus and a human.

Twenty-four strains were identified as L. interrogans serovar saxkoebing, most strains were isolated from either wood mice, bank or field voles but strains were also isolated from badgers, a fox and a dog.

For many years phage typing has proved invaluable in epidemiological studies on Salmonella typhi, S. paratyphi A and B, S. typhimurium and a few other serotypes. A phage-typing scheme for S. enteritidis is described. This scheme to date differentiates 27 types using 10 typing phages.

Cross-reactions of 17 members of the family Legionellaceae were studied by four different serological techniques: immunofluorescence (IF), slide agglutination (SA), microagglutination (MA) and immunodiffusion (ID), using antigens and rabbit antisera prepared in our laboratory. Results obtained corresponded closely with those described by other authors, especially for IF and SA.

The 17 antigens were further tested by IF with a panel of sera previously diagnosed as positive for legionella. A high number of positive reactions with several of the antigens tested were found, half of them being positive for Legionella pneumophila serogroup 1, usually in combination with other serogroups or species. The remaining sera presented a great variety of patterns combining different antigens.

Salmonella was the most frequent bacterial pathogen isolated from patients with acute diarrhoea in Hong Kong. In Queen Mary Hospital, the major hospital on Hong Kong Island, 94·7% of salmonellae isolated from faecal specimens from patients during the period 1973–82 belonged to the gastroenteric group, while 5·3% belonged to the enteric fever group. Amongst the gastroenteric group, 68 salmonella serotypes were identified, with Salmonella derby, S. typhimurium and S. analum being the predominant ones. Three outbreaks caused by S. johannesburg, S. worthington and S. wandsworth were detected.

Of S. typhimurium, 61·0% were resistant to multiple antibiotics and belonged to four major phage types: 193, 22, 138 and U288. The majority (96·8%) of S. johannesburg strains which caused a widespread epidemic were multiply-resistant. Multiple antibiotic resistance was rarely observed in most other gastroenteric salmonellae.

S. typhi was the commonest of the enteric fever group isolated from the blood of patients. Nineteen phage types were identified; E1 being the commonest (18·5%) while 21% were nontypable. Many of these isolated were resistant to streptomycin or sulphadiazine, but none were resistant to ampicillin, chloramphenicol or trimethoprim.

A total of 91 food and environmental samples were examined for the presence of salmonollao using a commercially available enzyme immunoassay kit (EIA) and a conventional culture technique. A 78% agreement was obtained, but re-examination of culture-negative, EIA-positive samples gave agreement of 86%. The problem of comparing EIA and culture results is discussed. A partially selective pre-enrichment broth was tested in 37 samples and gave better EIA ratios. Artificially contaminated cooked foods gave 100% agreement.

Five laboratories serving a population of 1·5 million participated in a 2-year survey of campylobacter, salmonella and shigella infections in patients suffering from gastrointestinal symptoms. In total, 33857 faecal specimens were examined of which 5·5% yielded campylobacters, 3·4% salmonellas and 0·8% shigellas; incidence of infection (per 100,000 population per year) was 58, 38 and 9 respectively. Peak incidences occurred at different ages for each organism: campylobacter, 1–4 years (183); salmonella, less than 1 year (181); shigella, 1–4 years (17). There was a secondary peak in campylobacter incidence in patients aged 15–24 years (87), which was not seen with salmonella or shigella infections.

By recording the age and sex of all patients submitting faecal specimens, it was shown that sampling rates were disproportionately high in infants aged less than 1 year (12:1 relative to other ages). Thus the percentage of faecal samples positive in infants – in sharp contrast to incidence values – was the lowest of any age group for all three organisms. By taking the numbers of faecal specimens tested as denominators in this way, the highest campylobacter isolation rates were in young adults, with a notable male predominance in the 15–24 year (1·7:1) and 45–54 year (1·6:1) age groups. This male predominance was accentuated during the summer (2·1:1) when incidence was generally high. The maximum percentage isolation recorded by any laboratory was 32·5% in males aged 15–24 years in June.

The reasons for this pattern of campylobacter infection are unknown, but the similarity of the results between laboratories and the regularity of the seasonal fluctuations recorded over the last G years indicate that the sources and routes of infection are geographically similar and stable, yet different from those of salmonellosis.

The usefulness of sodium dodecyl sulphate–polyacrylamide gel electrophoresis patterns of cell envelope proteins for classifying strains of Acinetobacter calcoaceticus was studied using 129 isolates from 16 in-patients in a teaching hospital. In 11 patients, all of the isolates from each patient exhibited the same pattern irrespective of the body site or time of isolation. The patterns of the isolates from four other patients were indistinguishable, with the exception of one isolate per patient. In the isolates from one patient five patterns were observed. In several cases isolates from different patients exhibited the same pattern. The relative frequency of some of these patterns was low. Epidemiological data were compatible with the assumption that the concurrent presence of bacteria of these patterns in the patients was the result of cross-infection. For one pattern, which was seen in seven patients, cross-infection could not be substantiated. On the basis of analysis of electrophoretic patterns in combination with epidemiological data on a number of strains it is concluded that cell-envelope protein profiles appear to be a useful aid in studying the dissemination of Acinetobacter in the hospital environment.

Plasmids present in multiply-resistant salmonella strains including Salmonella typhimurium, S. johannesburg, S. wandsworth, S. derby, S. newport, S. london and S. choleraesuis causing diarrhoea in patients in Queen Mary Hospital in Hong Kong from 1973–82 were studied. In multiply-resistant S. typhimurium, plasmids belonging to groups F1me, H1, or H2 and plasmids encoding trimethoprim-resistance which were compatible with standard plasmids of testable incompatibility groups were detected. In S. johannesburg, both the ASTCKSu- and ASCKSu- resistant strains which were predominant in two consecutive periods of an outbreak were found to harbour the same plasmid which belonged to the incompatibility group F1me. S. wandsworth strains isolated from a hospital outbreak in 1980 harboured an identical R-plasmid belonging to group N. A few strains of the other salmonellae showing resistance to multiple antibiotics were found to harbour R-plasmids belonging to groups H1, H2 and F1me. The only salmonella of the enteric fever group resistant to ampicillin, chloramphenicol and trimethoprim was an S. paratyphi B strain. The resistances were encoded on a plasmid of an unknown incompatibility group. The occurrence and distribution of plasmids in these salmonellae isolated within the 10-year period are discussed.

Isolates of Salmonella typhimurium, recovered over a 9-month period from a child with gastroenteritis, were characterized by biotyping, phage-typing and plasmid-profile analysis. Because the data from the different methods were discrepant, it was difficult to establish whether her infection was due to a single strain that had changed character in vivo or was due to recurrent infections with different, unrelated strains. Restriction-enzyme fingerprinting of the plasmids from the different isolates provided an explanation for the initial discrepancy and highlighted a source of potential confusion in epidemiological studies.

A total of 308 samples of different types were examined for the presence of salmonellas by means of three different procedures. The first consisted of preenrichment in buffered peptone water followed by enrichment in Rappaport-Vassiliadis medium (P/RV). The second differed only in that 1% Teepol was added to the pre-enrichment medium (PT/RV). In the third, buffered peptone water with 1% Teepol was followed by enrichment in Muller–Kauffmann tetrathionate broth also containing 1% Teepol (PT/MKT). The first of these combinations (P/RV) proved superior to the others both in terms of isolation rates and in the appearance of suspicious colonies.

Twenty-nine strains of penicillinase-producing Neisseria gonorrhoeae (PPNG) and 30 non-penicillinase-producing strains, all isolated in the Gambia, were characterized in terms of their plasmid content, auxotype and protein-I serovar. Sixty-two per cent of the PPNG strains contained the 3·2 MDa penicillinasecoding plasmid, and 38% had the 4·4 MDa plasmid. All the PPNG strains contained the 2·6 MDa cryptic plasmid but lacked the 24·4 MDa conjugative plasmid. In contrast, 46·7% of the non-PPNG strains harboured only the cryptic plasmid while 16·7% contained both the cryptic and conjugative plasmids. Seventeen per cent of the non-PPNG strains contained the conjugative plasmid only and 20% lacked plasmids.

The PPNG and non-PPNG strains also differed in terms of their protein-I serovar. Eighty-six per cent of the PPNG strains belonged to serogroup 1A, whereas the majority (60%) of non-PPNG strains belonged to serogroup IB. There was no significant difference in the auxotypes of the PPNG and non-PPNG strains, with both groups consisting predominantly of prototrophic and prolinerequiring strains, with a minority of strains requiring arginine. When the 59 strains were each characterized in terms of their combined plasmid profile, auxotype and serovar, 39 different combinations were noted, which indicates the heterogeneous nature of the gonococcal population found in the Gambia.

Samples of blended mutton tissue in small polyvinyl chloride sachets were incubated in water baths for different times and at varying temperatures. The temperature of each bath was recorded accurately throughout each experiment. Using equations previously derived for the lag and generation times of coliform organisms in blended mutton tissue, the expected increases of these bacteria were calculated from the time/temperature recordings. These were compared with the data obtained from plate counts made on the tissue samples in the sachets before and after incubation. The studies were done with a strain of Escherichia coli, one of Salmonella lyphimurium and the coliform organisms naturally present on sheep carcasses processed in a commercial abattoir. The calculated growth agreed closely with that measured. Therefore, if mutton, after overnight chilling, is warmed again to temperatures within the growth range of these bacteria, the possible increases in the numbers of cells present can be calculated directly from time and temperature measurements.

The implications for the present codes of practice in abattoirs are discussed.

Attempts were made to discover the source of strains of haemolytic Escherichia coli infecting weaned pigs on a piggery. The organisms were not detected in the faeces of sows in the farrowing house, or in the in the faeces or intestinal tracts of slaughtered bacon pigs or sows. Sows held in a quarantine unit, and their offspring born in the unit, did not excrete haemolytic E. coli until after they were returned to the piggery.

The environment of the piggery was the most likely source of infection for weaned pigs, and routine cleaning and disinfection of the accommodation did not prevent infection. Unweaned pigs were however able to transfer haemolytic E. coli to a newly built, previously unused weaning house, and establish a cycle of infection.

A total of 150 patients were treated for tetanus in the tetanus ward of the J. J. Hospital, Bombay, between October 1983 and January 1986. The complications of tetanus and the mode of management in the presence of restricted resources are outlined. Intensive care, proper nutrition, early tracheostomy and ventilator support in severe tetanus were chiefly responsible for an overall reduction in mortality from 30 to 12%. The mortality in severe tetanus was reduced from 70 to 23%.

Sudden death due to unexpected cardiac arrest was an important complication in severe tetanus. We observed that an abrupt marked rise in rectal temperature ( > 107 °F, 41·7 °C), if undetected, could lead to sudden circulatory collapse and death. Well-marked hypoxaemia was observed in all patients with severe tetanus, and was related to ventilation perfusion inequalities and to an increase in the true venous admixture (increased Qs/Qt)in the lungs. Bronchopulmonary infections and the adult respiratory distress syndrome added significantly to morbidity and mortality. Autonomic cardiovascular disturbances included bradycardia alternating with tachycardia, and hypertension which was either labile, paroxysmal or sustained. Persistent hypotension was of ominous significance. Amongst numerous complications involving other systems, sepsis and septic shock were associated with a high mortality.

An estimate for the source of coagulase-negative staphylococci in blood cultures is presented and its use illustrated in two populations. The method estimates the probability that a positive blood culture is positive due to contamination and the probability of it being positive due to bacteraemia. The effect of changes in efficiency of the blood culture technique on these estimates is demonstrated. One of the illustrative populations consists of 537 sample pairs from 273 patients, taken after open-heart surgery in 1978–80. The other consists of 500 consecutive sample pairs taken in one of two hospitals in 1983–4.

Two hundred and one strains of Staphylococcus aureus isolated from in-patients and out-patients were examined for sensitivity to antibiotics, heavy-metal ions and ethidium bromide and for phage-typing pattern.

Heavy-metal ion resistance was less frequent than reported in previous studies and was as frequent in penicillinase non-producing as producing strains. ‘Methicillin-resistant’ strains were resistance to ethidium bromide and mercury. Resistance to heavy-metal ions, including cadmium, may bo becoming less common amongst clinical isolates of S. aureus.