An Asian patient with undiagnosed typhoid fever was admitted to a maternity hospital and delivered within 10 mm. Salmonella typhi (phage type D5) was isolated from her blood and from the faeces of her baby. Another woman in a different room of the labour suite at the same time acquired the same organism in her faeces; her brother was admitted to the Infectious Diseases Unit 5 weeks later with typhoid fever. Two babies, born over 60 h after the index case was delivered, became faecal excreters of the same strain and one of them also developed S. typhi osteitis of the hip. These two babies and their mothers were in the same ward as each other, but not that occupied by the infected mother and her baby. Nine other excreters in two of the families involved were identified. The index case and her baby were isolated immediately after delivery, and the relevant rooms in the labour suite were adequately disinfected. No evidence of undisinfected equipment used by the index case and the other infected patients was found, and no spread to staff was detected. The mode of spread remains unknown.

A new instrument has been designed to measure the penetration by rubbing of bacteria from cloth contaminated in the nursing of burn patients through fabrics designed for barrier garments. Most fabrics tested dry reduced the transfer of bacteria from the source cloth to about 10%, irrespective of the results of air filter tests, which agrees with mock nursing results. When the fabrics were tested against a wet surface, the transfer of bacteria rapidly reached 100% if the fabrics had a high wettability, but was slower for fabrics with a low wettability. Through closely woven waterproofed cotton, transfer was 5–25%, but increased three- to four-fold after ten launderings, in line with the water absorption. Transfer through plastic-laminated material was less than 1%. The results suggest that barrier garments should be made either of plastic or of recently waterproofed closely woven cotton at points of contact between nurse and patient where the clothes may be wetted by bacteria-containing wound secretions.

Previous investigations have shown that cross-contamination in a burn unit is mainly clothes-borne. New barrier garments have been designed and tried experimentally. The aim of the present study was to investigate the effects of different clothing routines on cross-contamination. In a long-term study, the rates and routes of colonizations with Staphylococcus aureus, Streptococcus groups A, B, C, F, and G and Pseudomonas aeruginosa were examined. The exogenous colonization rates were, with S. aureus 77%, with Streptococcus species 52% and with Ps. aeruginosa 32%. The colonization rate with Ps. aeruginosa was higher in patients with larger burns. Patients dispersed Streptococcus and Ps. aeruginosa as well as S. aureus into the air of their rooms in considerable amounts, but dispersers were not more important as sources of cross-colonization than non-dispersers. In comparison of clothing routines, there was no difference in overall colonization rates. The newly designed barrier garment that was made from apparently particle-tight material did not reduce the transfer of bacteria from patient to patient. A less rigid routine than that previously used did not increase the risk of cross-contamination. A thorough change of barrier dress after close contact nursing delayed the first exogenous S. aureus colonization from day 6 to day 14 after admission. This routine might be recommended for clinical use. Otherwise, methods must be developed for adequate selection of materials intended for barrier garments.

An open-roofed plastic isolator was built in a single patient isolation room in a burn unit. It was designed to prevent contact contamination only, as this had been shown to be the important route of cross-colonization in the unit. To exclude any possible effect on airborne transfer of bacteria, the isolator was first examined by means of an airborne particle tracer of the same size as bacteria-carrying particles. Such experiments indicated that the isolator might prevent some transfer out of but not into the isolator. This was not confirmed in simulated nursing experiments nor in a patient study, where the air counts of bacteria were practically the same inside and outside the isolator wall. Two patients only were nursed in the isolator. Both patients acquired exogenous colonizations from other patients, one with Ps. aeruginosa and the other with S. aureus. Nursing in the isolator was difficult and staff-demanding. In simulated nursing experiments, plastic aprons and gaunt-lets as the only protective measures against contact contamination gave as much protection to a mock patient as did the isolator. S. aureus were released from nurses' clothes more easily during work with the isolator than in open nursing with aprons and gauntlets. In conclusion, the isolator did not seem to be a realistic alternative to impermeable clothes such as plastic aprons as a means of preventing clothes-borne cross-contamination between burn patients.

The influence of treatment with increasing oral doses of three absorbable antibiotics on the colonization resistance of the digestive tract was investigated in mice. Mice treated with ampicillin or epicillin in any of the applied doses had a strongly decreased colonization resistance as demonstrated by ‘bacterial over-growth’ after contamination with resistant strains of Escherichia coli. After a treatment period of 2 weeks, Streptococcus faecalis became resistant in a number of animals. Oral treatment with cephradine on the other hand had no obvious influence on the endogenous flora of the mice, nor was the colonization resistance decreased.

In recent years, mycoplasma taxonomists have found that numerous mycoplasma strains from goats are serologically indistinguishable from Mycoplasma mycoides subsp. mycoides, the causative agent of contagious bovine pleuropneumonia (CBPP), by routinely used tests, e.g. the metabolism-and growth-inhibition tests. As a result, such organisms are now openly referred to as M. mycoides subsp. mycoides.

Seven of these so-called M. mycoides subsp. mycoides strains from goats were compared with two strains of M. mycoides subsp. mycoides from CBPP, and with one strain of M. mycoides subsp. capri, by means of two in-vivo tests, namely, (1) a test of the ability of each strain, injected intraperitoneally into mice, to produce mycoplasmaemia, and (2) a cross-protection test in mice. Of the seven strains, only one (‘O goat’) was indistinguishable from genuine M. mycoides subsp. mycoides; it also had small colonies resembling those of genuine M. mycoides subsp. mycoides. The other six were easily distinguished from genuine M. mycoides subsp. mycoides, and they produced large colonies. These six strains and others like them should no longer be given a name that fails to distinguish them from the causative agent of CBPP.

Cross-protection tests showed that the seven goat strains referred to above differed from M. mycoides subsp. capri.

The specimens here described enlarge our knowledge of the bills of health of the Order of St John issued from Malta, an aspect of public health that had hitherto remained unexplored. These lone survivors from a vanished by-way of Maltese medical history formed, in their age, an integral part of the daily social, commercial and sanitary pattern of life in Malta. The earliest met so far, and described in the present series, dates from 1713; two belong to 1766 and another dates from 1794. A further bill, issued in 1782, has been published elsewhere. The chance preservation of these documents in unlikely places, as here indicated, makes it probable that additional ones may eventually come to light.

A bacteriological study was carried out on the first Leisure Centre swimming pools in the United Kingdom to be disinfected with ozone/chlorine. Results suggested that a free chlorine concentration of approximately 0·8 mg/l was necessary to maintain the pools in a bacteriologically satisfactory condition. This amount of free chlorine was similar to that required when the pool was disinfected with chlorine alone. However, the associated amount of combined chlorine was much lower when disinfection was by ozone/chlorine and this gave more acceptable bathing conditions. Implications for the management of pools disinfected by this method are discussed.

Antibiotic resistant strains of Escherichia coil were isolated from the domestic sewage of Palmerston North. The ability of these strains to transfer the drug resistance markers to two different recipient E. coli strains was assessed. The ‘O’ and ‘H’ serotypes of all strains were determined and attempts at correlation with the drug resistance studies were made. Some typically ‘human’ serotypes were found as well as a number of rarely described ones. No correlation between serotype and resistance pattern was observed.

In two controlled clinical trials of a polyvalent pseudomonas vaccine, vaccinated burned patients showed higher antibody titres to the 16 antigens in the vaccine and higher titres of a passively transferable protective antibody than was found in unvaccinated burned patients.

A test is described for assessing the sanitizing effect of napkin treatment products on naturally urine-wetted and faecally-contaminated napkins. This test defines in-use conditions which closely resemble typical domestic situations. One napkin treatment product (‘Napisan’), tested at two different concentrations and with challenges of different numbers of babies' napkins, performed satisfactorily under the conditions used.

Coliforms isolated from infections over a period of 22 months were examined and 16° were shown to be klebsiellas. The biochemical reactions and serotypes of these klebsiellas were determined and the relationship between species, serotype and type of infection investigated. Although no obvious outbreaks of infection occurred during this period a number of clusters of isolations of the same serotype of klebsiella were found.

Using an enrichment method for the isolation of klebsiellas from faeces, sero and bacteriocin typing, and the examination of ten colonies, it was demonstrated that half of the patients carried a klebsiella of the same type in the bowel as caused the infection.

For 29 months the Veterinary Investigation Centres, covering the whole of Great Britain, forwarded trimethoprim-resistant gram negative enteric bacteria to the Wellcome Research Laboratories. These were examined for degree of resistance, presence and type of R factors. Trimethoprim resistance was found in 0·6 % of the total number of strains examined by the Veterinary Investigation Centres. Trimethoprim R factors were demonstrated in one quarter of the resistant strains, and R factors were found in two strains of Salmonella typhimurium. It was concluded that while the incidence of trimethoprim resistance revealed by the survey gave no cause for alarm, the detection of resistant strains, and particularly R factors, indicated that the drug should continue to be used only for specific therapeutic purposes.

Intranasal vaccination with a single 0·5 ml dose of 107.0 EID 50 WRL 105 strain live influenza vaccine elicited four-fold or greater increases in circulating homotypic haemagglutinating inhibiting (HAT) antibody in 60 (64·5 %) of 93 volunteers, or in 58 (74·4%) of 78 volunteers with HAI antibody titres before vaccination of ≤ 1/20. In comparison, in a group of volunteers vaccinated 9 months previously re-vaccination elicited antibody responses in only 4 (6·9 %) of 58 volunteers, or in 3 (14·3%) of 21 volunteers with antibody titres before vaccination of ≤ 1/20.

Titres of vaccine-induced antibody and antibody resulting from earlier natural infection appeared to fall slowly and at equivalent rates over a 9 month period.

Aqueous suspensions of Staphylococcus aureus were deposited on a Millipore filter and then exposed for a few seconds to 70 % ethyl alcohol. Viable counts of bacteria extracted from the filter immediately after exposure to alcohol, and, in replicate experiments, after a further period of 3 h, showed that the mean immediate reduction of 97·6 % in viable counts after treatment with alcohol was followed by a further mean reduction of 67· 1 % in the further 3 h holding time; the same bacterial suspensions allowed to dry on Millipore filters without exposure to alcohol showed a significantly smaller mean reduction in viable counts (34·3 %) during a further 3 h holding time. These findings support the view that the reported further fall in numbers of bacteria on hands while wearing gloves for 3 h after alcohol disinfection can be explained by sublethal damage to some of the bacteria, from which they can recover only if promptly inoculated on culture medium.