Two outbreaks of salmonella food poisoning are described. In one, involving 55 persons, the infecting organism was Salmonella reading, and in the other, involving 39 persons, S. tennessee. In both, epidemiological and bacteriological evidence pointed to imported cans of cooked meat as the source. The role of contaminated shop equipment in furthering the spread of infection is particularly emphasized.

Attention is drawn to the severity of the symptoms and prolonged excretion of the organism in a number of the patients infected with S. reading.

Between October 1963 and April 1965, 113 children with respiratory disease and 113 children with diarrhoeal disease were matched for age and time of entry into hospital and studied by virus isolation and serological techniques.

Infections with respiratory syncytial (RS) virus, parainfluenza virus and herpes simplex virus respectively were found in 29, 11 and 12 children in the respiratory illness group but in only 1, 2 and 4 children in the diarrhoeal group. Rhinoviruses were isolated from 10 children in each group and in seven cases were associated with lower respiratory disease. Adenovirus infections were found in nine children with respiratory disease and eight with diarrhoea. Of the 40 enteroviruses isolated 16 were associated with respiratory disease and 24 with diarrhoea.

A poor or delayed serological response in children under 4 months with RS virus infection was observed. Addition of unheated rabbit serum increased the sensitivity of the neutralization test with RS virus.

These findings indicate that respiratory syncytial and parainfluenza virus infections were clearly associated with respiratory illness but the pathogenic role of the other viruses was not clear.

Forty-one children in an Edinburgh nursery were observed for evidence of respiratory illness from November 1963 to April 1964. During this period serial specimens of serum from these children were examined for virus antibodies and serial throat swabs were investigated for the presence of virus. Well-defined outbreaks of respiratory illness occurred and could be associated with respiratory syncytial virus, parainfluenza 3 virus and influenza C virus infection. Infection with adenovirus followed a more endemic pattern. The antibody response in infants to respiratory syncytial virus as measured by the standard complement-fixation test was found to be much poorer than the response to parainfluenza 3 virus. It is suggested that this may play a part in the severity of respiratory syncytial virus infection in infants.

Experiments were made to find out whether the common communion cup is likely to serve as a vehicle for the transmission of infection.

A silver chalice and sacramental wine containing 14·5% of alcohol were used. Observations with volunteers showed that the number of organisms deposited on the rim of the chalice varied from person to person, but was usually quite small—less than 100.

Rotation of the cup was of no benefit except to those partaking during the first round, since the saliva deposited on the rim by each person in turn remained to contaminate the cup during the second round, and the combined effect of the alcohol and the silver of the chalice was not rapid enough to destroy the contaminating organisms before rotation of the cup was completed.

On the other hand the use of a linen cloth or purificator led to a diminution of about 90% in the bacterial count of the cup.

Organisms in saliva deposited on the interior of the dry chalice suffered some diminution in numbers within 8 min., presumably as the result of the disinfectant action of the silver, but the effect was too small to be of significance.

When suspended in wine and deposited on the internal surface of the chalice Escherichia coli suffered a substantial reduction within 3 min., Streptococcus pyogenes was destroyed completely; but Staphylococcus aureus was affected to a much less extent.

Various experiments designed to measure the disinfectant action of wine, and of silver and wine together, showed that the augmenting effect of silver on the disinfectant action of the alcohol was quite small. Strep. pyogenes proved to be far more sensitive to alcohol than Esch. coli, Staph. aureus and Serratia marcescens. Under the conditions of the experiment these last three organisms were not destroyed for 10–12 min., whereas Strep. pyogenes perished within 1½ min.

The results of our work are in general agreement with those of previous workers, and show that the organisms deposited on the rim of the communion cup are not destroyed within the short time—5 sec. as an average—elapsing between the partaking of the sacrament by each successive communicant.

It must therefore be admitted that the common communion cup may serve as a means of transmitting infection. Reasons are given, however, for believing that the risk of transmission is very small, and probably much smaller than that of contracting infection by other methods in any gathering of people.

Such risk as there is could be greatly diminished by the use of a purificator for wiping the cup between each communicant, and could be abolished completely by substituting individual cups or by the practice of intinction.

The Lf values of diphtheria toxoid alone and in combination with tetanus toxoid or tetanus toxoid plus pertussis vaccine, dried by sublimation in vacuo, sealed under nitrogen, exposed to elevated temperature and rehydrated thereafter were not altered. Lf values declined in samples sealed under air. The values for Kf in the above preparations increased in relation to increased temperatures of exposure for a given time or following exposure to a given temperature for increased time intervals. The sensitivity of the system of testing used was greater following the addition of ‘helper’, a fast flocculating solution of diphtheria toxin, and in the case of dried diphtheria toxoid stored under adverse conditions (sealed under air) for two years, the addition of ‘helper’ was necessary to obtain a flocculation reaction. In general, the results obtained indicated a very high stability for preparations sealed under nitrogen, and a significantly lower stability for preparations sealed under air.

1. A marked sex variation in susceptibility to warfarin was found in 6-month old L.A.C. Grey mice, males being more susceptible than females. No sex difference in response was evident in young mice 6 weeks old.

2. Susceptibility to warfarin poisoning increased markedly with age in males but not in females.

3. No significant increase in mortality following warfarin poisoning occurred in adult female mice given methyl testosterone.

Experimental infection of captive Common Terns with Influenza virus A/Tern/South Africa/1961 reproduced the disease seen in the 1961 epizootic during which Tern virus was originally isolated. Infected terns excreted virus in their droppings. At death a viraemia was present but immunofluorescent studies determined the sites at which virus reproduction occurred. A Swift Tern suffered no ill effect from the injection of Tern virus but developed HI antibodies. The role of migrant sea-birds in spreading avian influenza is briefly discussed.

The properties of naturally occurring poliovirus strains of each serotype have been studied using three marker tests: the R.C.T.40 test, intratypic serodifferentiation and, for type 1 strains only, inhibition by dextran sulphate.

The results show that while most strains resemble the prototype strain of the same serotype, considerable natural variation exists, especially in the ability to grow at temperatures between 39° and 40° C.

No correlation has been found between the results of the tests on individual strains and it is concluded that no single test is sufficient to characterize a strain.

Strains of poliovirus were obtained from 13 of the 18 persons in England and Wales with paralytic episodes after administration of oral vaccine in 1962. They have been studied using three marker tests: the R.C.T.40 test, intratypic serodifferentiation and inhibition by dextran sulphate. For comparison a number of strains from subjects with non-paralytic vaccine-associated reactions and from patients with paralytic poliomyelitis not related to vaccine were also tested.

Of the eight patients excreting type 1 strains seven came from South Wales where an outbreak was in progress. They all resemble naturally occurring strains from the outbreak in growing at 39·3° but not at 39·8° C.

Only one subject excreted type 2 virus which was of vaccine type.

The type 3 strains included a series from a family group where a range of results from vaccine to the wild range was obtained. Three other patients with vaccineassociated paralysis excreted type 3 strains with the characteristic of naturally occurring strains.

A micro-organism, previously known as the J agent, was grown on solid medium: its various characteristics suggested that it was a mycoplasma and it was provisionally named Mycoplasma suipneumoniae.

In the growth-inhibition and metabolic-inhibition tests, M. suipneumoniae was indistinguishable from M. hyopneumoniae (Maré & Switzer, 1965).

By the growth-inhibition test, M. suipneumoniae seemed unrelated to all of a wide range (42 strains) of other mycoplasmas examined. These results suggest that, if the similarity between M. suipneumoniae and M. hyopneumoniae is substantiated in further work, these latter two strains are probably a new species.

M. suipneumoniae was also identified by the metabolic-inhibition test, by precipitation in agar gel, and by immune-fluorescence. Using the last two methods, M. suipneumoniae was distinguished from a second porcine mycoplasma (strain 603).

The most important property of M. suipneumoniae is its ability to induce enzootic pneumonia experimentally in pigs.

Heating at 37° C. for 5 days completely abolished the capacity of a trachoma/inclusion conjunctivitis (TRIC) vaccine to protect baboons against conjunctival infection. Treatment with formalin also impaired or abolished immunogenicity.

The rate of inactivation of TRIC agent by ultraviolet light was exponential, and was about 7 times faster than that of a suspension of vaccinia virus of comparable turbidity. By contrast with vaccinia, irradiation of TRIC agent with twice the dose of ultraviolet light needed to destroy infectivity resulted in loss of immunogenicity.

The deleterious action of these inactivation procedures on the potency of TRIC vaccines may be explained in terms of damage to a protective antigen; alternatively, live vaccines may be more immunogenic because TRIC agents are capable of multiplying within primate hosts after parenteral injection.

Unlike the same type of variant of another strain of inclusion conjunctivitis, the ‘fast-killing’ variant of MRC-4 was still pathogenic for the baboon conjunctiva.

Chick embryos were inoculated with measured doses of various strains of the agents of trachoma and inclusion blennorrhoea, and the number of infective organisms they contained was determined at intervals during the first 4 days after inoculation. From curves of the yield of agent at different times relative to the dose inoculated, it was evident that the lag phase before the exponential phase of growth began was shorter for fast-killing—and more virulent—variant strains than for slow-killing strains, and the difference was statistically significant; and that variant strains multiplied faster during the exponential phase of growth and produced then- highest titres sooner.

The conditions for satisfactory fumigation with formaldehyde were investigated using suspensions of Staph. aureus and Ps. aeruginosa dried as drops on strips of polythene or after mixing with cotton dust. In laboratory experiments with controlled concentrations of formaldehyde and water vapour, satisfactory results were obtained at 86 % humidity, but at 32 % humidity the formaldehyde was virtually inactive.

Measurements under field conditions showed that the permanganate method of vaporizing formaldehyde did not vaporize enough water to produce optimum conditions for sterilization, and that great care was necessary in the sealing of rooms. When sterilization was incomplete the surviving organisms were not uniformly distributed within the room.

In the limited circumstances in which fumigation with formaldehyde is thought to be essential, the process should be controlled by estimating the formaldehyde and water vapour concentrations initially and after 3 hr.