This paper consists of an epidemiological study of 52 cases of Q fever occurring in metropolitan Adelaide in 1957 and also a description of the results of a survey of 516 sera obtained from abattoir workers.

The only case occurring outside the abattoirs was a dairy farmer who probably became infected while visiting the abattoirs. If this were so the incubation period (35 days) of his disease would have been exceptionally long.

The general features of the outbreak, which lasted several months, differed from those on the North American continent in that the latter occurred explosively within a few days with very high attack rates. The situation in the Adelaide abattoirs is similar to that in Brisbane, where the disease appears to be endemic. However, unlike in Adelaide, cases are commonly recognized outside the abattoirs in Brisbane.

In the abattoirs the disease affected mainly inspectors, those working on killing beef, and those working on offal. Mutton workers were not so severely affected. However, all these groups had similar incidences of low titre antibodies suggesting that in the past Q fever spread equally in all killing departments. In departments not directly associated with slaughtering the incidence both of cases in 1957 and low titre antibodies was relatively small.

It was suggested that the epidemiological features of Q fever in Adelaide could be explained by the irregular appearance of animals from infected herds situated perhaps in Queensland—a known endemic area. Perhaps the appearance of such animals in the Adelaide abattoirs might be governed by meteorological conditions such that they were prevented from going to the ordinarily most convenient slaughterhouse.

Sera of 132 selected patients belonging to stages II, III or IV of clinical trachoma have been tested by CF-test against the ether-soluble, group-specific Bedsonia antigen, as well as by CF-inhibition test against an indicator system of the same group-reactive specificity.

On the basis of the serological results obtained, the following conclusions have been advanced:

Trachoma patients do not develop group-specific CF-inhibiting antibodies in their sera.

The group-reactive (anti-Bedsonia) CF-titres found in sera of trachoma patients represent residual titres developed in response to past infections with agents other than trachoma. There is no satisfactory explanation for the fact that in trachoma patients neither CF, nor CF-inhibiting antibodies develop against the group-reactive Bedsonia antigen, which is known to be produced also by the virus of trachoma.

Statistical analyses revealed that, in the group of stage IV trachomas, the mean values of the anti-Bedsonia CF-titres were significantly higher than those found in the groups of stage II or III, as well as that the factors responsible for that difference must be other than the duration of the trachoma.

A hypothesis was advanced to explain the appearance of the highest group specific mean-titre revealed by the group of stage IV cases.

The result of penicillin prophylaxis of experimental inhalation anthrax in the Rhesus monkey has been shown to be dependent upon the time of its initiation. If begun too early, it is unsuccessful. It may not be too long delayed, or the infection will have passed the point of no return. A brief, critical time period exists, during which successful prophylaxis may be initiated. This favourable outcome is attributed to the elaboration in vivo of sufficient antigen or antigens to stimulate an adequate immune response, prior to the initiation of antibiosis.

1. Ten strains of Sh. sonnei were placed upon metal, wood, cotton, paper, and glass and held at −20°, 4°, 15°, 37° and 45° C. Survival of the cells was most extensive when placed at −20° C. and practically none of the strains survived when held at 45° C.

2. Slight variations in the survival of different strains was observed when the cells were placed upon glass and cotton. Strain variation was greater when survival time was measured by placing Sh. sonnei on wood, paper, and metal.

Cowpox soluble antigen is shown by gel-diffusion studies to contain at least nine precipitable substances whose presence is induced by virus infection. One of these substances, pattern component d, is not produced in white cowpox infections, and its production in vaccinia infection can be inferred only from the presence of small amounts of anti-d in anti-vaccinia sera.

Comparison of cowpox with vaccinia has led to the recognition of a further line pattern component f which is readily demonstrated as a soluble precipitable substance in simple buffer extracts of vaccinia-infected tissue, but is demonstrated in extracts of cowpox-infected tissue only with difficulty; anti-f antibody is readily detected in antisera prepared against cowpox, white cowpox, and vaccinia.

A longitudinal survey of respiratory illness in a Sheffield residential nursery is described. Over 8 months, outbreaks of respiratory illness occurred, two of which were associated with infection by Influenza A and Parainfluenza 3 viruses. The symptomatology is described of the illnesses resulting from these infections. The incidence of adenovirus recoveries over the same period was also investigated and suggests that adenoviruses of Types 1, 2 and 5 may be components of the normal viral flora of the nasopharynx in infants.

A description is given of a precipitin test, using potent non-infectious antigens, which can be performed in laboratories not specializing in virology. Trial of the method as a diagnostic procedure gave positive results in 100% of a series of 50 patients with acute poliomyelitis. Precipitation lines, almost always sharply defined and intense, were obtained in 89% of 33 sera within 3–8 days of onset of acute poliomyelitis and in all sera after the 8th day. In positive cases precipitation bands usually appeared within 24 hr. after starting the test. In all instances precipitation was homotypic with the type virus isolated from stools. Double bands appeared in very recent cases but only with homotypic precipitins. Single heterotypic lines appeared in 12 cases due to previous infection or perhaps due to infection by virus strains with common antigens. All control patients with nervous system disease other than poliomyelitis or with infection by Coxsackie or ECHO viruses and all control test animals gave negative results. Of 240 poorcommunity schoolchildren who had taken monovalent oral poliovaccine 4½ months previously, 80% had precipitins for Type 1, but less than 5% showed marked reactions. The sera from the remainder gave only weakly positive results. Contrasting with transience of precipitins, neutralizing antibodies persisted in nearly 100% of children tested.

The precipitin test was used to study antibody response to ingestion of trivalent oral vaccine (prepared and issued by the Poliomyelitis Research Foundation, Johannesburg). More than half (54 %) of 90 students who received the vaccine had positive precipitin-test results; most often these results appeared during the 2nd week after ingestion. In this positive group 54 % showed multiplication of at least two types and 12 % showed multiplication of all three types poliovirus.

A preparation of vaccinia virus inactivated by ultra-violet irradiation under strictly controlled conditions, and shown to produce neutralizing antibody and resistance to challenge in rabbits, was active in only about half of 37 human volunteers. It was not, therefore, likely to be usefully immunogenic in man. In the largest single test, 15 of 25 men had unmodified primary skin reactions when challenged with living virus, although five of these had circulating antibody. On the other hand, only three of 10 men who responded to challenge with modified or negative reactions, had no circulating antibody.

In man the presence of circulating antibody does not necessarily indicate resistance to infection in the skin, nor does skin immunity always indicate the presence of circulating antibody.

1. The effect of blanket-disinfection on aerial contamination of exposed culture plates was studied during a six-month trial in six hospital units, containing a total of 270 beds.

2. Disinfecting blankets after use by each patient did not significantly reduce general bacterial or Staph. aureus counts on exposed culture plates.

3. Disinfected blankets were heavily recontaminated after only a few days' use. A quaternary-ammonium rinse during laundering conferred no self-disinfecting properties on them.

4. Cotton-cellular blankets were more economical and more popular with patients and nurses than were conventional woollen and two other types of cotton blanket.

Over a certain range there is a linear relationship between the amount of complement required for 50 % lysis and the amounts of one of the variables in the primary reaction mixture of a complement-fixation test when the third variable is present in a quantity sufficient to allow maximum fixation.

If this linear relationship were maintained as the concentration of the selected variable is progressively reduced, there would also be a linear relationship between the logarithms of the amounts of complement fixed and the logarithms of the amounts of the selected variable; in this case, the line with logarithmic co-ordinates will necessarily have unit slope.

When the fixation of small amounts of complement by several virus systems is measured, an approximately linear relationship using logarithmic co-ordinates has been demonstrated, but in many cases the line does not have unit slope. In this range, therefore, there is not a linear relationship when arithmetic co-ordinates are used.

A new design for a complement-fixation test is proposed, using isohaemolytic curves.

A serious outbreak of staphylococcal infections in the maternity units in Blackburn was investigated. There were considerably more than one hundred cases of breast abscesses altogether, well over half of which occurred in primiparae. Staphylococcus aureus, phage type 80, was the predominating organism throughout the outbreak and at the peak period during the early part of the outbreak this type was responsible for nearly 80% of the infections.

After the introduction of a number of procedures for the general reduction of cross-infection the incidence of breast abscess fell markedly and a controlled trial of an antibacterial cream, containing neomycin and hibitane, which was applied to the nasal mucosa of all infants and mothers in the test group of patients, was undertaken. The conditions obtaining in the test and control groups were identical in every way except that the control patients did not receive the neomycin-hibitane cream. There were about 1250 mothers and infants each in the test and control groups; the incidence of breast abscesses in the test group was 0·8% and in the control group it was 2·7%. The method adopted for the detection and treatment of carriers among the nursing staff broke down on two occasions; this fact and the emergence of an unforeseen source resulted in a larger number of infections than should have occurred. Had it not been for these incidents there is little doubt that the trial would have shown more conclusively the effectiveness of the neomycinhibitane cream, by the method laid down, in reducing cross-infection.

Investigation of the bacterial flora on the nasal mucosa of over 1000 infants in the control group yielded results of considerable interest. Of 300 cases where there was early colonization by Staph. albus, this organism established its dominating position in 70% of the cases and it was not subsequently displaced by Staph. aureus. The significance of this observation and the evidence favouring nasal dissemination of Staph.aureus as the most important cause of hospital cross-infection are discussed.

A simple micro-method of measuring ‘D-’ and ‘C-’ antigen contents of poliovirus preparations is described. The D-antigen of poliovirus is almost certainly the component of the virus involved in eliciting neutralizing antibodies, and the D-antigen assay thus becomes a simple in vitro method for assessing the antigenic potency of poliovaccines and for investigating the influence of various factors upon the antigen. The value of the technique in following the concentration and purification of poliovirus preparations is illustrated in the studies reported in the accompanying paper by Fantes (1962). The results of experiments designed to test the validity of the idea that D-antigen is the antigen eliciting neutralizing antibodies are discussed by Beale (1961).

1. Conditions are described under which the three types of live or formalin-inactivated poliomyelitis viruses can be concentrated 10–100 times in good yield, with elimination of approximately 90% of the extraneous protein normally present in poliovaccines.

2. It was shown that 0·1–0·2 mg./ml. AlPO4 almost quantitatively adsorbed the antigens, provided the adsorptions were carried out at a pH round about 5. Re-elution of the antigens occurred readily at pH 7–pH 8.

3. No noticeable conversion of the ‘D-antigen’ to the ‘C-antigen’ occurred during the concentration.