Outbreaks of wound infection with Streptococcus pyogenes and Staphylococcus aureus occurred in an abattoir and a pork-processing factory in Autumn 1980. Investigations showed that staff handling the meat before de-boning were particularly affected and that bone was the cause of 48 % of the wounds which became clinicially infected. Of the total isolates of Strep. pyogenes and Staph. aureus from wounds of known cause 75% were from lesions caused by bone. In one outbreak streptococcal infection was seen principally in newly-employed staff. Group L streptococci were found in several sites in the pork factory and were isolated from infected lesions in two workers. Strep. pyogenes and Staph. aureus were cultured from tap handles in the lavatories.

Sixty-six workers were examined in a non-epidemic period and 59 % were found to have current wounds on the hand or wrist; 13% of wounds were infected but Strep. pyogenes was not isolated. Bone was the commonest of the many causes of injury, accounting for 31 % of all wounds. Butchers had the highest rates of wounding and most bone-inflicted injury was seen in this group. Packers were the only group to wear protective gloves regularly. Damaged fingernails were found in 50% of workers, including a high proportion of nail-biters (33% of all workers). The epidemic strain of Staph. aureus was cultured from bitten fingernails. Three of four infected workers carrying epidemic organisms in the throat were examined and all were nail-biters. Sharp-edged bone was produced by rotary saws early in the production line and bone dust contaminated the carcasses and adjacent surfaces. It is suggested that bone fragments could contaminate wounds and that this might have implications for the initiation of infection and the development of outbreaks.

A total of 321 Salmonella typhimurium strains of bovine origin obtained in northern Japan during the period 1970–1979 were tested for drug resistance and detection of conjugative R plasmids. Three hundred and eighteen (99·1 %) of these strains were resistant to one or more drugs. The isolation frequency of multiply drug-resistant strains tended to increase year by year. Two hundred and thirty-seven (74·5%) of these resistant strains carried conjugative R plasmids. A total of 308 R plasmids including 174 (56·5 %) thermosensitive (ts) R plasmids were derived from the 237 drug-resistant strains, indicating that 71 (30·0%) strains have two different conjugative R plasmids in a single host cell. Of the 308 R plasmids examined for fertility inhibition (fi), 167 ts and 131 non-ts R plasmids were fi−. Of the 60 ts R plasmids examined for incompatibility, 50 were classified into H1 group and 10 into H2 group. Of the 52 non-ts R plasmids examined, 35 were classified into the Iα group and the remaining plasmids were untypable in our tests. Mercury resistance marker was found in about 20% of H1 R plasmids coding for multiresistance, and all of H2 R plasmids coded for resistance to tellurite. The clonal distribution of an S. typhimurium strain which carried an H1 R plasmid coding for resistance to six drugs and mercury was recognized in 1978 and 1979.

Corynebacterium haemolyticum infections are described for the first time in Sri Lanka. In a period of 2 years from 1978–80 C. haemolyticum was isolated from the pharynx of 9 patients with tonsillitis and from local septic lesions in 7 other patients. Association with other pathogens was common. No patients had a rash. The properties of the isolates are described.

A survey conducted in 1980, 9 years after the banning of the use of tetracyclines as feed additives in the U.K., indicated that table chickens and pigs were still a large reservoir of tetracycline-resistant Escherichia coli; the incidence of transferable tetracycline resistance was greater in chicken E. coli strains (68%) than in pig E. coli strains (20%). Large amounts of sulphonamide-resistant and of furazolidone-resistant E. coli were found in the faeces of chickens; E. coli resistant to both sulphonamides and streptomycin were common in the faeces of chickens and pigs. E. coli with transferable or mobilizable trimethoprim resistance were present in the faeces of most pigs and in the faeces of 10 % of chickens.

The incidence of Vibro parahaemolyticus in products of the Malaysian export shrimp processing industry was investigated through the stages from the catch to that of the cooked, peeled and frozen product. The organism was commonly found in freshly caught and landed shrimp, and could be detected by enrichment culture at all stages of processing. The numbers of V. parahaemolyticus in shrimp varied from nil to 4 × 104, and 19 of the 50 serotypes in the current antigenic scheme were found, O1-K38 and O1-K32 occurring most often. All the isolates were Kanagawanegative; one strain was a sucrose-positive variant. The study indicated that specifications of 102 g−1 for V. parahaemolyticus in raw tropical shelfish are too stringent but that the Malaysian shrimp industry should be able to meet this requirement for cooked shrimp.

During a period when 245 patients were infected by or harboured gentamicinresistant enterobacteria, random sampling showed hand carriage in 33% of affected patients but in only 5 % of attendant staff. Only klebsiellae were isolated from the latter. Recovery was commoner from the hands of bed-ridden patients or faecal carriers and significantly more frequent for klebsiellae (37 %) and enterobacter (33 %) than citrobacter (5·6 %) and E. coli (5·0 %). Similarly, survival on forearms of volunteers was much longer for klebsiellae and enterobacter than for citrobacter or E. coli (means respectively were 70, 45, 10 and 13 min), and on dry surfaces (means respectively were 28, 26, 3 and 7h). Klebsiellae were isolated from 17 of the 56 dry environmental surfaces sampled. The presence of plasmid resistance determinants had no effect on survival times, either on the skin or following drying onto formica surfaces. On dry surfaces 9·5% of E. coli but only 1·3% of klebsiellae lost resistance to gentamiein. These findings accord well with recent experience in which gentamicin-resistant klebsiellae have been involved to a much greater extent than other resistant enterobacteria in hospital infection.

The India-ink Immuno-reaction (IIR) was used as a simple, convenient procedure for the detection of carriers of enteric organisms in an unselected sample of patients attending a mission clinic at Kubacha in a remote area of Kaduna State, northern Nigeria. To assess the reliability of this procedure in difficult working conditions a similar population from the same clinic was subsequently examined by routine bacteriological culture techniques. Because of a temporary shortage of suitable anti-sera we were unable also to examine specimens from this second group by IIR.

A further group of patients attending the out-patients clinic of the General Hospital in Kaduna with symptoms of acute enteric disease was investigated using both IIR and routine culture.

Proportionally more positive results were obtained for Salmonellae, Shigellae and Vibrios with IIR than with routine culture. A larger scale controlled survey is desirable to evaluate the procedure further.

The Microbact-24E and the Microbact-12E systems are two new miniaturized identification systems for the identification of organisms belonging to the family Enterobacteriaceae. These two systems were compared to the API-20E system for the identification of 352 fresh clinical isolates of Enterobacteriaceae. All three systems were easy to use and came complete with computerized profile registers to assist with final identification of the isolates. The Microbact-24E identified 98 %, the API-20E and MB-12E identifying 94·3% and 88·6% respectively. Where different identifications were obtained with the Microbact-24E and API-20E conventional biochemical tests, motility and serology were performed. The Microbact-24E system proved to be a very accurate and convenient means of identifying members of the family Enterobacteriaceae.

Small numbers of Salmonella dublin were used to infect calves in an attempt to simulate natural infection on the farm.

Twenty calves were exposed to S. dublin by one or more of the following methods:

Sucking cows which were excreting S. dublin in their faeces (⋜ 102–105 organisms/g).

Housing on S. dublin contaminated bedding.

Drinking S. dublin contaminated water (102–104 organisms/ml). During this experiment some calves were given therapeutic doses of oxytetracycline.

After exposure the calves were examined for faecal excretion of S. dublin (in some instances mouth swabs and blood samples were also examined) and for clinical signs of illness. Most of the calves became infected with S. dublin but excretion was usually sporadic and the numbers of salmonellas excreted were small. No clinical signs of salmonellosis were observed by S. dublin was isolated from one calf at post-mortem.

Another six calves, dosed orally with either 106 or 108S. dublin, showed signs of mild illness and although three calves had diarrhoea excretion of salmonellas was intermittent. S. dublin was isolated from one of these calves at post-mortem.

Bacteroides spp. were isolated from the faeces of neonates and identified by rapid modifications of established conventional methods. Gram-negative anaerobic bacilli were recovered from 12 out of 16 neonates and a heavy growth of Bacteroides spp. was obtained from all 12 specimens. Twelve representative isolates from each subject were selected for identification; 141 of the 144 Bacteroides isolates belonged to the B. fragilis group and three to the B. melaninogenicus/oralis group. Eight species were represented within the B. fragilis group. B. vulgatus (c. 46%) and B. thetaiotaomicron (c. 30 %) were the predominant species. B. fragilis, the type-species of the group, formed only a small proportion of neonatal faecal flora. The proportional representation of individual species were similar to that found in adults but B. asaccharolyticus was not represented.

Echovirus type 11 (echo 11) has been isolated at the virus laboratory of Fairfield Hospital, Melbourne, Australia, in 20 of the 28 years since the laboratory was established. During this time two major epidemics have occurred; the first, in 1971–2 involved 90 patients with aseptic meningitis or respiratory illness. The second began in June 1979 and lasted for 11 months, during which echo 11 was isolated from 174 patients admitted to Fairfield Hospital, other Victorian and Tasmanian hospitals and a children's reception centre. The patients' illnesses included viral meningitis (66%), fever (10%), respiratory infections (7%) and gastroenteritis (2%). One baby died.

Echo 11 was recovered from nasopharyngeal swabs or aspirates, cerebrospinal fluid and faecal specimens and was isolated most frequently in the Borrie cell line. Isolates were readily identified by immune electron microscopy and/or neutralization tests.

An investigation was undertaken to see if cooking or cold storage would destroy or decrease the level of biologically active antibiotic in tissues from animals given therapeutic doses of antibiotic on three occasions prior to slaughter. The effects of cooking and cold storage on the biological activity of the residues of ampicillin, chloramphenicol, oxytetracycline, streptomycin and sulphadimidine were varied; in some instances the effects were minimal, in others nil.

In August, 1980 a rare serotype S. zanzibar was isolated in the North of Scotland from a man home on leave from Malaysia, whence he returned in November having been bacteriologically negative 2 months previously. In December however, S. Zanzibar was isolated from a bulk milk sample taken at a nearby dairy farm. No illness occurred among milking cows which had been brought inside from pasture in mid-October. Since 1972 a variety of different salmonella serotypes had been identified in cattle, milk and other samples at this farm, with seagulls being implicated as the vector transmitting infection from the sewage of a local town on to farmland and an adjacent loch. Although water from this source has not been used in recent years for drinking by cattle, it is utilized for washing floors within the dairy premises. Since 1979, following an outbreak affecting consumers, all milk produced at the farm has been pasteurized.

Steatorrhoea was a significant feature in an outbreak of rotavirus gastroenteritis which affected adults and infants in hospital. Fat globules or fatty acid crystals were obvious by light microscopy (LM) in faeces from 14 of 25 patients examined. Ten of the fatty stools and two of the remainder were very pale. By electron microscopy (EM) a rotavirus was seen in 11 of the 14 fatty faeces and in only two of 11 specimens without visible fat.

In a further study of pale or fatty faeces 20 such specimens sent for laboratory examination from patients not involved in the hospital outbreak were compared microbiologically with a similar number which were neither pale nor fatty. Viruses were found by EM in 11 (55%) of the pale or fatty stools; eight rotaviruses, two astroviruses and an uncultivable adenovirus were seen; one further patient had acute jaundice. In contrast, no viruses were seen by EM in the twenty specimens which were normally pigmented and without evident fat.

Steatorrhoea was significantly associated with rotavirus infection of the alimentary tract which usually presented as a fatty enteritis. We conclude that rotaviruses certainly, and other viruses possibly, can impede both the digestion of fat and the pigmentation of the faeces. Inspection and LM of faeces are easy. In acute enteritis a fatty or pale stool is an indication for virological examination.

Small colony (SC) strains of Mycoplasma mycoides subsp. mycoides from contagious bovine pleuropneumonia (CBPP) and from goats were compared with large colony (LC) strains of so-called M. mycoides subsp. mycoides from goats and sheep by means of a cross-protection test in which mice were challenged with M. mycoides subsp. capri.

Of 13 LC strains, all gave partial cross-protection, and 11 were shown to be more closely related than four SC strains to subspecies capri. In a further experiment, six SC strains – three from CBPP and three from goats – all gave weak partial cross-protection against subspecies capri.

Sera or serum eluates from 1697 wild rabbits [Oryctolagus cuniculus (L)], collected over the past 10 years from 24 sites in 5 geographic regions of Victoria, were examined for antibodies to Toxoplasma gondii. Sera generally were classified into three broad groups, negative (titre < 10), weakly reactive (titre 10 to 100) and strongly positive (titre > 1000). Strongly positive sera came from rabbits collected in a small number of localized areas, most significantly the Melbourne and Metropolitan Board of Works (MMBW) Sewerage Farm at Werribee and Mud Island in Port Phillip Bay.