We investigated the potential effects of COVID-19 public health restrictions on the prevalence and distribution of Neisseria gonorrhoeae (NG) genotypes in our Queensland isolate population in the first half of the year 2020. A total of 763 NG isolates were genotyped to examine gonococcal strain distribution and prevalence for the first 6 months of 2020, with 1 January 2020 to 31 March 2020 classified as ‘pre’ COVID-19 restrictions (n = 463) and 1 April 2020 to 30 June 2020 classified as ‘post’ COVID-19 restrictions (n = 300). Genotypes most prevalent ‘pre’ restrictions remained proportionally high ‘post’ restrictions, with some significantly increasing ‘post’ restrictions. However, genotype diversity was significantly reduced ‘post’ restrictions. Overall, it seems public health restrictions (9–10 weeks) were not sufficient to affect rates of infection or reduce the prevalence of well-established genotypes in our population, potentially due to reduced access to services or health-seeking behaviours.

HArris & LEong (1936) found that vitamin B1; adsorbed from urine, could be measured by the rat bradycardia method of assay. The amount of vitamin B1 excreted was found to correspond in general with both the dietary intake and the physiological state of the subjects.

A new COVID-19 vaccine was introduced in a remarkably short period of time. Public and healthcare workers (HCWs) were concerned about the safety of the vaccine, especially in light of the use of new technologies. A review regarding attitudes towards COVID-19 vaccination found a 22.5% hesitancy rate among HCWs. Online anonymous questionnaires were delivered using a web-based surveying platform to community HCWs in a central district in Israel from 3 to 19 January 2021. The real COVID-19 vaccination data were collected between the beginning of the vaccination rollout and the end of the month after the survey as well as the real vaccination rate among the general population. Of the 3,172 HCWs, 549 (17%) responded to the questionnaire. The highest positive attitude towards the vaccine was among physicians (95%), while nurses showed the highest level of hesitation (14%) for a specific sector (P < 0.05). However, the real vaccination rates were similar among physicians (63%) and nurses (62%). Surprisingly, the total vaccination rate of HCWs was substantially lower (52%) than that of the general population (71%). The main vaccination motivators were the social and economic effects of the COVID-19 epidemic. Focused strategies to reduce the level of hesitancy among HCWs are needed.

That out breaks of plague are associated with a more or less simultaneous mortality amongst rats is an observation of great antiquity. After the discovery of the bacillus by Yersin and Kitasato this concomitant disease of rats was identified as plague, and during the last twelve years the association of rat plague and human plague has been shown to be almost invariable. The relationship has been so striking that many observers who have studied the question on the spot, e.g. Yersin, Ogata, Simond, Thompson, Koch, Gaffky and many others, have arrived at the opinion that from an epidemiological point of view one must regard plague as essentially a rat-disease in which human beings may participate.

The following conclusions appear to us to be justified as a result of the experiments cited above:—

(1) Close contact of plague-infected animals with healthy animals, if fleas are excluded, does not give rise to an epizootic among the latter. As the go-downs were never cleaned out, close contact includes contact with faeces and urine of infected animals, and contact with, and eating of food contaminated with, faeces and urine of infected animals, as well as with pus from open plague ulcers. This conclusion is justified from Experiments I and II and especially from Experiment VI, in which close contact with infected animals was maintained for nearly a month. In Experiment I the animals were inoculated cutaneously, and in many cases had developed ulcers at the site of inoculation.

(2) Close contact of young, even when suckled by plague-infected mothers, did not give the disease to the former.

(3) If fleas are present, then the epizootic, once started, spreads from animal to animal, the rate of progress being in direct proportion to the number of fleas present. Thus, in the experiments during the months of December, January and February, the epizootic was very rapid in those go-downs, namely, Nos. 1 and 2, Experiments IV and V, in which the flea population was abundant and was kept up by a natural supply from the roof: it was much slower in Experiment VII, go-down No. 5, in which the flea supply was kept up artificially; and, finally, it was slowest of all in go-down No. 6, Experiment VI, in which there was no definite natural supply of fleas, and from which the fleas were daily removed for a period of six days, after which removal only a comparatively small number could be caught.

(4) An epizootic of plague may start without direct contact of healthy animal and infected animal. Thus, in the case of Experiment V in go-down No. 1 the healthy guinea-pigs were not put in until the last inoculated guinea-pig had died and been removed.

(5) We have in Part II shown by direct experiment that the rat flea can convey plague from rat to rat. Further experiments (Experiments VI, VII and XI) of a similar nature with the fleas removed from infected go-downs are now recorded.

(6) Infection can take place without any contact with contaminated soil. Thus in go-downs Nos. 1 and 2 (Experiments VIII, IX), guinea-pigs placed in wire cages two inches above the ground developed plague; also the monkey in go-down No. 2 (Experiment XIII) was never in contact with the ground.

(7) Aerial infection is excluded. Thus, guinea-pigs suspended in a cage two feet above the ground did not contract the disease, while in the same go-down those animals allowed to run about and those placed two inches above the floor became infected. Further, the monkey surrounded by tangle-foot was exposed as much to aerial infection as the control animal which contracted the disease.

As mentioned in Chapter 1, the Brown Institution was staffed by a remarkable series of Superintendents, seven out of eight of whom were, or became, Fellows of the Royal Society. Much of the research work they undertook has already been referred to in preceding chapters, but it seems only fitting that something should be said about their personalities and careers. In preparing the short accounts that follow, I am greatly indebted to obituary notices in the various scientific journals, especially those in the Proceedings of the Royal Society; to the pen sketches given by Professor Sharpey-Schafer (1927) in his History of the Physiological Society;and to the Memoirs in book form of Sir John Burdon-Sanderson by his wife (1911)and of Sir Victor Horsley by Sir Stephen Paget (1919).

Growth agglutination and growth inhibition tests were established for the diagnosis of Brucella abortus infection. The former involves the agglutination of living organisms while the latter is a bactericidal test. Using mouse, guinea-pig, rabbit and bovine serum it was shown that the growth agglutination test is approximately ten times, and the growth inhibition test one hundred times, more sensitive than the conventional tube agglutination test. It is suggested that these techniques may be of assistance in diagnosing bovine brucellosis in situations in which the tube agglutination test results are suspected of being falsely negative.

Pregnancies were identified in which maternal IgG antibodies against rubella virus were not detectable by single radial haemolysis. Twenty paired maternal/cord sera were then tested for haemagglutination-inhibiting (HI) activity against rubella virus without kaolin pretreatment of the sera. In the absence of specific antibody, the HI activity observed could thus be ascribed to the effect of non-specific inhibitors. The HI activity in maternal sera was significantly (P < 0·001) higher than that in cord sera. The 20 pairs of sera were similarly tested against a bunyavirus, an alphavirus and a flavivirus, both with and without kaolin pretreatment. The results showed non-specific inhibitors were found to higher titre in maternal sera, with the difference being statistically significant (P < 0·001) for each of the three viruses.

The presence of antibodies in the body fluids of the offspring of immunised parents has long been studied and variously explained. In 1912, Famulener2 published a clear summary of the work upon the subject up to that date. Renewed interest in the problem has been aroused by the work of the Department of Animal Pathology of the Rockefeller Institute for Medical Research, where the transmission of immunity to the Bacillus abortus is being studied. It has been shown by Little and Orcutt3 that agglutinins for this bacillus are transferred exclusively by the colostrum, since a calf from which colostrum is withheld does not show this agglutinin in its serum, although a high titre of agglutinin may be demonstrable in both serum and colostrum of the dam. Later Orcutt and Howe4, using a method of separating the protein fractions of serum devised by the latter5, 6, showed that the appearance of agglutinins in the serum of a calf fed with colostrum of high agglutinin titre was closely related to the appearance of euglobulin, which is absent from the blood of the newly born calf. Further, Smith and Little7 showed that this absorption of agglutinin from the digestive tract also occurred when the calf was fed with serum rich in that antibody. The association of agglutinin with the globulin fraction of serum, and in particular with the euglobulin fraction, has been demonstrated by Orcutt and Howe4, who found that “the agglutinins are associated with the protein fractions which are precipitated up to and including 16·4 per cent. of sodium sulphate,” and that “a large proportion of the agglutinins is associated with the fraction which is precipitated by 14·2 per cent. of sodium sulphate, euglobulin.” Again, although a milk might show a high titre of agglutinin, with no corresponding increase in the proportion of its globulin, yet the agglutinin was removed from the milk by a concentration of sodium sulphate which removed the globulin fraction of the protein.

To assess the relative importance of ulcerative and non-ulcerative sexually transmitted disease in the transmission of HIV, a seroprevalence study was conducted on 2210 patients at the sexually transmitted diseases (STD) clinic of the S. Maria e S. Gallicano Hospital in Rome, between 1989 and 1994. Among male patients, by univariate analysis, strong predictors of HIV infection were homosexuality, sexual exposure to a HIV-positive partner, hepatitis B virus infection, and positive syphilis serology. An increased risk was estimated for patients with past genital herpes (odds ratio (OR) 3·86, 95% confidence intervals (CI) 0·40–18·2), and primary syphilis (OR 5·79, 95% CI 0·59–28·6). By multivariate analysis, a positive association was found with homosexuality (OR 6·9, 95% CI 2·9–16·5), and positive syphilis serology (OR 3·5, 95% CI 1·3–9·2). An adjusted OR of 2·41 was calculated for current and/or past genital herpes. These results, although not conclusive, suggest a role of ulcerative diseases as risk factors for prevalent HIV infection, and indicate that positive syphilis serology is an unbiased criterion for identifying individuals at increased risk of HIV infection.

The Harbour of Poole lies a few miles to the West of Bournemouth. It has an area approximately of 10,000 acres, but there is only a very narrow passage between its waters and the open sea. The width of this bottle-neck entrance is about 250 yards. The last published Admiralty chart gives the rate of the incoming tide through this narrow entrance at 3¼ knots, and of the outgoing tide at 4 knots. The local opinion is that these official rates err on the moderate side. The rapid ebb and flow of the tides has an influence in the bacteriology of the oysters within the harbour.

A considerable degree of uniformity of results of the Wassermann test has been found among five pathologists.

Certain differences (chiefly in the case of weakly positive sera) have, however, been noted. Their main source lies in the use of different methods and not in any lack of personal ability or care on the part of the worker.

It is believed that the number of these could be greatly reduced by adopting a uniform method of performing the test and by standardising the details of the method.

The supply of a standard antigen and haemolysin to pathologists is recommended.

Investigations carried out to ascertain the ability of various strains of Bordetella pertussis and B. parapertussis to produce agglutinins have shown that the agglutinin response is considerably greater with B. parapertussis.

Children inoculated with a combined vaccine in which the parapertussis element contained B. parapertussis in only one-twelfth of the concentration of B. pertussis in the pertussis element showed agglutinins in their sera in titres well above 1:300 for both organisms. There were no cross-reactions and the serological responses were specific throughout. The vaccine used was the standard diphtheria-tetanus-pertussis (DTP) prophylactic to which had been added a vaccine prepared from recently isolated strains of B. parapertussis.

Agglutinin titres of both whooping cough components with the combined vaccine were somewhat lower in mice than was the case when monovalent vaccines were used, but they were considered to be satisfactory.

It is suggested that the agglutination production test in mice could be used for the assessment of protective power of B. parapertussis vaccines against infection.

I wish to thank Dr Ikić, director of the Institute of Immunology, Zagreb, who enabled me to perform all these examinations, further to Dr B. Mravunac and Dr Z. Radanov for having carried out vaccination in children and for the clinical examination of post vaccination reactions.

Previous studies of boys at Christ's Hospital school have indicated that annual immunization with influenza virus vaccines did not significantly reduce the total incidence of influenza infection compared to unimmunized subjects. In view of the implications of this result, a similar study was conducted in ferrets to clarify these findings. Groups of ferrets were immunized or infected with a series of influenza A (H3N2) viruses over an 18-month period, and the immunity to subsequent live virus challenge was measured after each virus or vaccine exposure. The results indicated that live virus infection gave a more solid immunity than immunization with inactivated vaccine; and the serum haemagglutination-inhibiting antibody response was greater following immunization than following infection. In addition, differences in immunity could not be explained by measurements of cross-reacting and specific antibody, since the incidence of these antibodies was similar in both infected and immunized animals. The results do not suggest an explanation for the different levels of immunity induced following infection or immunization or the results obtained from the Christ's Hospital study. However, the relative contribution of various immune responses to virus or virus antigen is discussed, and it is suggested that the difference in immunity may lie in the ability of live virus infection to stimulate local antibody.

Gaseous insecticides, such as methyl bromide and methallyl chloride, are being used on an increasing scale against insects attacking stored products such as grain, tobacco, etc. Their use involves two possible dangers. In the first place, the worker may be poisoned either during the actual gassing operation or during the preparatory period. Secondly, there is the possible danger to consumers through the absorption of these furnigants into the stored product.

Multicomponent cyclicity in influenza (flu) incidence had been observed in various countries (e.g. periods T = 1, 2–3, 5–6, 8·0, 10·6–11·3, 13, 18–19 years) and its close similarity with cycles in natural environmental phenomena as meteorological factors and heliogeophysical activity (HGA) suggested. This report aimed at verifying previous results on cyclic patterns of flu incidence by exploring whether flu annual cyclicity (seasonality) and trans-year (13 to <24 months) and/or multiannual (long-term, ⩾24 months) cycles might be present. For this purpose, a relatively long monthly flu incidence dataset consisting of absolute numbers of new cases from the Grand Baku area, Azerbaijan, for the years 1976–2000 (300 months) was analysed. The exploration of underlying chronomes or, time structures, was done by linear and nonlinear parametric regression models, autocorrelation, spectral analysis and periodogram regression analysis. We analysed temporal dynamics and described multicomponent cyclicity, determining its statistical significance. The analysis, considering the flu data specifically stratified in three distinct intervals (1976–1990, 1991–1995, 1996–2000), and also combinations thereof, indicated that the main cyclic pattern was a seasonal one, with a period of T = 12 months. Further, a number of multiannual cycles with periods T in the ranges of 26–36, 62–85 or 113–162 months were observed, i.e. average periods of 2·5, 6·1 and 11·5 years, respectively. Indeed, most of these cycles correspond to similar cyclic parameters of HGA and further analyses are warranted to investigate such relationships. In conclusion, our study revealed the presence of multicomponent cyclic dynamics in influenza incidence by using relatively long time-series of monthly data. The specific cyclic patterns of flu incidence in Azerbaijan allows further, more specific modelling and correlations with environmental factors of similar cyclicity, e.g. HGA, to be explored. These results might contribute more widely to a better understanding of influenza dynamics and its aetiology as well as to the derivation of more precise forecasted estimates for planning and prevention purposes.

1. The red blood corpuscles of different species have definite and distinct mean lytic points.

2. The apparent tonicity of sheep serum has no relation to the mean lytic point of the red corpuscles of that individual.

3. The apparent tonicity of sheep serum is not due to its proteins but to its lipoids.

4. The residue of sheep serum, after removal of proteins and lipoids, is sufficiently alkaline to cause lysis.

1. Immunity cannot be completely explained by antigen-antibody reactions, even if the term ‘antibodies’ be made sufficiently elastic to include various obscure properties which are exhibited, in vivo, in the actively immune animal. Various other factors have to be considered. One of these is the influence of stimuli upon the vital capacities of bacteria.

2. Transmissible bacterial autolysis appears to be due to a stimulus acting upon the growing bacterial cell and leading to the splitting off of a certain number of daughter-cells which are non-viable, and consequently undergo autolysis.

3. Transmissible autolysis is not due to a stimulus sui generis but is no more than a particular incident in the general phenomena of bacterial variation.

4. The secretions of bacteria in pure culture may stimulate, control, or retard their growth and may lead to the production of variants.

5. When introduced into the animal body, bacteria encounter stimulants of animal origin which may be either favourable or unfavourable to their growth and are to be distinguished from the stimulants attributable to the bacteria themselves.

6. One aspect of the differences between natural immunity and natural susceptibility may be interpreted as due to differences in the stimuli inherent in the particular animal species and to consequent differences in their effects upon the particular bacterial species.

7. Similarly, when no better explanation is available, the acquired immunity (active or passive) of a susceptible animal may be interpreted as a change of the animal's stimulant action from one which was favourable (or indifferent) to the growth of a bacterium to one which is adverse, i.e., a stimulant to the reproduction of daughter-cells which are non-viable in the animal body.

8. Leucocytes are one of the sources of material possessing two kinds of properties, viz., (a) stimulant action on the growth capacities of cells (both bacterial and animal) and (b) enzyme action on the constituents which living and dead cells possess in common. The older researches on the characters of leucocytic extracts were occupied with (b), though they may occasionally be linked up with (a), since there are some indications that their leucocytic material was also acting as „lytic substance.”

9. In some cases it must remain, for the present, an open question whether demonstrable antibacterial action is attributable to some more or less obscure enzymes or to what I have termed „stimuli.”

10. A stimulus may be a substance which is also an antibody, and its stimulative properties may be highly specific. But it would be absurd to assume that for each special kind of stimulative effect there is a special and chemically distinctive kind of stimulus. Both stimuli and antibodies usually possess a wide range of different combining affinities which cannot be explained on the „mosaic” theory that each different combination is due to the presence (in the stimulus or antibody) of a different chemical group.

11. A stimulus, as distinct from a food, causes the bacterial cell to function in a particular way but is not incorporated as part of the structure of the cell. This convenient distinction, however, does not imply that there is necessarily a sharp line of demarcation between a stimulus and a food.

No hygienist has any doubt that diseases of the intestinal tract, especially the enteric fevers, may be spread by the consumption of shellfish. Clinical experience, often repeated, led to this conclusion long before the bacteriologist had been able to detect the presence of the causative organism in the shellfish. In fact it is only within the past year that definite proof has been afforded by the exceedingly valuable work of Wilson (1928), who found B. typhosus in cockles taken from Belfast Lough.