Streptococcus pneumoniae is an important cause of community-acquired pneumonia and pneumococcal conjugate vaccines (PCVs) may reduce this burden. This study's goal was to analyse trends in lower respiratory tract infections (LRTI) hospitalisations before and during a routine vaccination programme targeting all newborns with PCV was started in the province of Quebec, Canada in December 2004. The study population included hospital admissions with a main diagnosis of LRTI among 6–59 month-old Quebec residents from April 2000 to December 2014. Trends in proportions and rates were analysed using Cochran-Armitage tests and Poisson regression models. We observed a general downward trend in all LTRI hospitalisations rate: from 11·55/1000 person-years in 2000–2001 to 9·59/1000 in 2013–2014, a 17·0% reduction, which started before the introduction of PCV vaccination. Downward trends in hospitalisation rates were more pronounced for all-cause of pneumonia (minus 17·8%) than for bronchiolitis (minus 15·4%). There was also a decrease in the mean duration of hospital stay. There was little evidence that all-cause pneumonia decreased over the study period due mainly to the introduction of PCVs. Trends may be related to changes in clinical practice. This study casts doubt on the interpretation of ecological analyses of the implementation of PCV vaccination programmes.

Our knowledge of the antigens of the typhoid bacillus has recently been enlarged by the investigations of Felix & Pitt (1934).

It has been recognized that the Vi antigen, newly established by these workers, is not only a very important factor in immunity, but also apparently a more labile substance than the O antigen hitherto regarded as the portion of the typhoid soma vitally concerned with the production of prophylactic immunity.

Four hundred and seven clinical isolates of Escherichia coli were examined for the presence of plasmids. These isolates comprised 189 which were collected irrespective of antimicrobial resistance (VP) and 218 which were collected on the basis of high-level trimethoprim resistance (TPR). The VP isolates were divided into drug sensitive (VPS) and drug-resistant (VPR) subpopulations.

Plasmids were detected in 88% of VP isolates (81% of VPS and 94% of VPR) and 98% of TPR isolates. The distribution of plasmids in both groups and subpopulations was very similar. However, there were small but statistically significant differences between the plasmid distributions. These showed that more isolates in the resistant groups harboured plasmids than in the sensitive subpopulation (VPS) and that the number of plasmids carried by resistant isolates was greater. Multiple drug resistance was significantly more common among TPR isolates than the VPR subpopulation and this was paralleled by increased numbers of plasmids.

Fifty-eight per cent of VPR and 57% of TPR isolates transferred antimicrobial resistance and plasmids to E. coli K12. Of the R+ isolates, 60% carried small plasmids (MW < 20Md) and 52% of these co-transferred with R-plasmids. These results are discussed.

The population structure and transmission of Escherichia coli in a small group of individuals isolated for 26 weeks on an Antarctic base were studied by multilocus electrophoresis of eight enzymes and plasmid analysis. Two hundred and sixty-nine strains were isolated. They were grouped into 60 allozyme types (ETs). Half of these ETs were only isolated once; others were repeatedly isolated from single subjects. Eleven were found in more than one subject and the pattern of the occurrence of some of them was considered to provide evidence of their spread from subject to subject.

The cell membrane of Mycoplasma gallisepticum was isolated by lysing the cells with digitonin. Chemical and density-gradient analyses and electron microscopy showed the isolated membranes to be relatively free of cytoplasmic contaminants. The density of the membranes exceeded that of other mycoplasma membranes, indicating a higher protein content. Small vesicular extensions seen in the sectioned membranes were interpreted as empty blebs.

The isolated membranes, but not the cytoplasmic fraction, elicited in chickens the production of growth-inhibiting, agglutinating and haemagglutination-inhibition antibodies to M. gallisepticum in titres resembling those obtained by injection of whole cells. The peak of the serological response varied with the serological test employed. The rapid slide-agglutination test became positive as early as 3 days after the first injection of only 50 μg. of membrane protein. The haemagglutination-inhibition antibody titre reached its peak at about 10 days after the first injection, while that of the growth-inhibiting antibodies was reached only at about 25 days. The addition of adjuvant to the membrane antigen did not improve the production of the growth-inhibiting antibodies in chickens, but it produced some improvement in rabbits. Our results support the thesis that the chief immunogens of M. gallisepticum reside in the cell membrane of this organism.

Trials of aqueous and oil adjuvant vaccines in young adult volunteers showed that severe local reactions were rare. However, the incidence of minor symptoms was too high for a vaccine which requires to be administered repeatedly. In contradistinction to some reports, systemic and allergic reactions did not constitute a problem.

Temperature has a profound influence on the rate at which changes appear in a carcase. A very low temperature indefinitely postpones the apparent changes.

The optimum temperature seems to coincide with that which is most suitable to the activities of ferments and bacteria present in the living body. Alterations in temperature, such as occur in exposed carcases, during the day and night, probably influence putrefaction by their effects on bacterial activity, antagonism, and symbiosis. Variations in temperature conditions may produce changes more profound than would appear likely on superficial consideration. The optimum temperature for one group of organisms is different from the optimum conditions for another. Changes in temperature, therefore, especially if they are of some duration, are apt to favour some groups at the expense of others, and influence in this way the whole sequence of subsequent events.

Water is necessary to the growth of bacteria. It permits of their migration in the tissues, allows their ferments to act, distributes by diffusion the substances on which they live, and dilutes the toxic products of their activity.

The effects of temperature and moisture cannot be dissociated for it is in combination that these factors exert their greatest influence.

In a hot dry atmosphere the removal of water by evaporation may be so rapid that a small carcase may become desiccated before putrefaction has advanced far. In hot arid countries a variety of influences inimical to putrefaction are at work, especially when carcases are resting on dry sand. The strong sunlight tends to destroy the skin organisms, which we believe to be the most important agents in producing putrefaction. The skin soon becomes horny in consistency, imprisoning the organisms within it, and preventing their invasion of the tissues. The horny skin protects the carcases from moisture from any source, and the exudation of fluid finally results in mummification.

In a hot moist atmosphere sunlight is robbed of much of its bactericidal power, and the conditions most favourable to putrefaction prevail. Moisture from the air, rain water and water from the ground are absorbed and keep the skin moist. Suitable conditions for the growth and penetration of skin and soil organisms are thus created. Very soon the superficial layers of the epidermis are loosened and the sodden skin permits the autolytic enzymes, passing from the deeper parts, to exert their action on it and assist the putrefactive organisms. The aerobic conditions now prevailing in the skin aid disintegration. The protective influence of the skin is thus lost, and water has free access to the underlying tissues, where it exerts its elutriating and solvent effects. The products of putrefaction are diluted and removed and the dissemination of organisms favoured. Oxidation now plays some part in the process and disintegration proceeds rapidly. The presence of maggots seems to hasten putrefaction.

Such considerations ought to be sufficient to suggest the inadvisability of treating decomposing animal matter with watery solutions of antiseptics as is so often done. Here we may point out that the flesh can be completely macerated from the bones in six days, if a carcase is kept in water at 37° F. The progress is especially rapid, if the water is changed after three days, and the products which seem to inhibit bacterial growth removed.

Within a few days of death, the time varying with the conditions, certain phenomena are noticed if a carcase is kept under observation. It becomes distended with gas, fluid exudes from it, and the skin over certain areas becomes green. These phenomena are usually regarded as evidences of putrefaction. Since in properly treated carcases they are not followed by disintegration of the proteins, which form the main constituents of the body, and since they appear to be due partly to enzyme action and partly to the action of intestinal bacteria of the colon-type on such constituents as carbohydrates, and not to the action of putrefactive organisms, we consider that we are justified in regarding these phenomena as precursors of true putrefactive changes. By the latter term we understand the disintegration of the tissues by putrefactive organisms, a process accompanied by the elimination of foul-smelling products.

The evidence on which this conclusion is based has been given in detail in this section, and here we propose to discuss only the more important considerations.

Although true meningococci are represented in serum 1, as shown by the high agglutination figure reached with serum 1 in the case of subculture 8, it appears that the antigenic value of strain 1, as represented in serum 1, finds its chief expression in “giant” forms, the morphological equivalent of films 3, 14, 17, 23, 31 A, from the subcultures which give the highest readings with serum 1 (except 8), being mainly that of “giant” forms in various stages of development. As I showed in 1916 “giant” forms may be either large, small or intermediate in size, and can at once be distinguished from true meningococci on the warm-stage by the fact that they often multiply by unequal binary fission, and by the further fact that they often undergo in addition endo-chromatinolysis, giving rise directly to meningococci which then divide in the ordinary vegetative manner. These fertile “giant” forms are readily distinguishable form forms undergoing genuine involutionary changes, both by the sterility of the latter when observed on the warm stage and by their feebly-staining properties.

This is a review of existing data on the burden of shigellosis in Thailand to determine trends, vulnerable groups, predominant species and serotypes, and antimicrobial resistance patterns. Diarrhoea and dysentery morbidity and mortality data from 1991 to 1999 was collected from the routine surveillance system and demographic data from the government census. International and local literature published between 1988 and 2000 was systematically reviewed. Based on the routine surveillance system, the annual incidence of bacillary dysentery decreased from 1·3 to 0·2/10000 persons per year. The remaining burden is highest in children <5 years of age at 2·7/10000 persons per year. In comparison, a prospective study utilizing active surveillance found an incidence in children <5 years of age that was more than 100-fold higher at 640/10000 persons per year. Despite the decrease in morbidity and mortality based on routinely collected data, shigellosis remains an important problem in children <5 years of age in Thailand.

Evidence was presented to support a hypothesis that competition between antibody molecules can be an important factor in vaccinia virus neutralization.

It has been shown that there is little difference in the virus neutralizing properties of 7 S and 19 S antibody and it has been further postulated that in the context of protective immunity the proportions of antibodies having neutralizing and interfering effects is likely to be more important than the absolute concentration of neutralizing antibody or the type of immunoglobulin in which it is present.

Significant ethnic and socio-economic disparities exist in infectious diseases (IDs) rates in New Zealand, so accurate measures of these characteristics are required. This study compared methods of ascribing ethnicity and socio-economic status. Children in the Growing Up in New Zealand longitudinal cohort were ascribed to self-prioritised, total response and single-combined ethnic groups. Socio-economic status was measured using household income, and both census-derived and survey-derived deprivation indices. Rates of ID hospitalisation were compared using linked administrative data. Self-prioritised ethnicity was simplest to use. Total response accounted for mixed ethnicity and allowed overlap between groups. Single-combined ethnicity required aggregation of small groups to maintain power but offered greater detail. Regardless of the method used, Māori and Pacific children, and children in the most socio-economically deprived households had a greater risk of ID hospitalisation. Risk differences between self-prioritised and total response methods were not significant for Māori and Pacific children but single-combined ethnicity revealed a diversity of risk within these groups. Household income was affected by non-random missing data. The census-derived deprivation index offered a high level of completeness with some risk of multicollinearity and concerns regarding the ecological fallacy. The survey-derived index required extra questions but was acceptable to participants and provided individualised data. Based on these results, the use of single-combined ethnicity and an individualised survey-derived index of deprivation are recommended where sample size and data structure allow it.

Different countries, especially Brazil, that have faced recurrent dengue epidemics for decades and chikungunya epidemics since 2014, have had to restructure their health services to combat a triple epidemic of arboviruses – Zika, dengue and Chikungunya – transmitted by the same vector, mainly Aedes aegypti, in 2015–2016. Several efforts have been made to better understand these three arboviruses. Spatial analysis plays an important role in the knowledge of disease dynamics. The knowledge of the patterns of spatial diffusion of these three arboviruses during an epidemic can contribute to the planning of surveillance actions and control of these diseases. This study aimed to identify the spatial diffusion processes of these viruses in the context of the triple epidemic in 2015–2016 in Rio de Janeiro, Brazil. Two study designs were used: cross-sectional and ecological. Sequential Kernel maps, nearest-neighbour ratios calculated cumulatively over time, Moran global autocorrelation correlograms, and local autocorrelation changes over time were used to identify spatial diffusion patterns. The results suggested an expansion diffusion pattern for the three arboviruses during 2015–2016 in Rio de Janeiro. These findings can be considered for more effective control measures and for new studies on the dynamics of these three arboviruses.

A suspected dengue fever outbreak occurred in 2010 at a solitary construction site in Shenzhen city, China. To investigate this epidemic, we used serological, molecular biological, and bioinformatics techniques. Of nine serum samples from suspected patients, we detected seven positive for dengue virus (DENV) antibodies, eight for DENV-1 RNA, and three containing live viruses. The isolated virus, SZ1029 strain, was sequenced and confirmed as DENV-1, showing the highest E-gene homology to D1/Malaysia/36000/05 and SG(EHI)DED142808 strains recently reported in Southeast Asia. Further phylogenetic tree analysis confirmed their close relationship. At the epidemic site, we also detected 14 asymptomatic co-workers (out of 291) positive for DENV antibody, and DENV-1-positive mosquitoes. Thus, we concluded that DENV-1 caused the first local dengue fever outbreak in Shenzhen. Because no imported case was identified, the molecular fingerprints of the SZ1029 strain suggest this outbreak may be due to vertical transmission imported from Southeast Asia.

Unpurified and purified smallpox vaccines were prepared from calf dermal pulp, or chorioallantoic membrane (CAM) of hen eggs infected with vaccinia virus, and freeze-dried. The protective effect of various suspending media was investigated both in the course of the freeze-drying and in the period of subsequent storage of the dried product at different temperatures, including 100° C.

Single media consisting of either sodium glutamate or peptone were effective in the preservation of both unpurified and purified vaccines prepared from calf dermal pulp or CAM. It was shown that there was an optimal concentration of sodium glutamate for the preservation of the vaccine preparations, especially of the purified vaccine.

Combined media, consisting of soluble starch, polyvinylpyrrolidone or sodium carboxymethyl cellulose with sodium glutamate, were effective with the purified vaccine when the concentration of sodium glutamate exceeded the optimum necessary for preservation.

The food court at a shopping mall is a potential transfer point for pathogenic microbes, but to date, this environment has not been the subject of detailed molecular microbiological study. We used a combination of culture-based and culture-independent approaches to investigate the types and numbers of bacteria present on food court tables, and on a food court cleaning cloth. Bacteria were found at 102–105 c.f.u./m2 on food court tables and 1010 c.f.u./m2 on the cleaning cloth. Tag-pyrosequencing of amplified 16S rRNA genes revealed that the dominant bacterial types on the cleaning cloth were genera known to include pathogenic species (Stenotrophomonas, Aeromonas), and that these genera were also evident at lower levels on table surfaces, suggesting possible cross-contamination. The evidence suggests a public health threat is posed by bacteria in the food court, and that this may be due to cross-contamination between cleaning equipment and table surfaces.

This study describes risk factors associated with mortality among COVID-19 cases reported in the WHO African region between 21 March and 31 October 2020. Average hazard ratios of death were calculated using weighted Cox regression as well as median time to death for key risk factors. We included 46 870 confirmed cases reported by eight Member States in the region. The overall incidence was 20.06 per 100 000, with a total of 803 deaths and a total observation time of 3 959 874 person-days. Male sex (aHR 1.54 (95% CI 1.31–1.81); P < 0.001), older age (aHR 1.08 (95% CI 1.07–1.08); P < 0.001), persons who lived in a capital city (aHR 1.42 (95% CI 1.22–1.65); P < 0.001) and those with one or more comorbidity (aHR 36.37 (95% CI 20.26–65.27); P < 0.001) had a higher hazard of death. Being a healthcare worker reduced the average hazard of death by 40% (aHR 0.59 (95% CI 0.37–0.93); P = 0.024). Time to death was significantly less for persons ≥60 years (P = 0.038) and persons residing in capital cities (P < 0.001). The African region has COVID-19-related mortality similar to that of other regions, and is likely underestimated. Similar risk factors contribute to COVID-19-associated mortality as identified in other regions.

Healthcare-associated infections (HAIs) are a major worldwide public-health problem, but less data are available on the long-term trends of HAIs and antimicrobial use in Eastern China. This study describes the prevalence and long-term trends of HAIs and antimicrobial use in a tertiary care teaching hospital in Hefei, Anhui, China from 2010 to 2017 based on annual point-prevalence surveys. A total of 12 505 inpatients were included; 600 HAIs were recorded in 533 patients, with an overall prevalence of 4.26% and a frequency of 4.80%. No evidence was found for an increasing or decreasing trend in prevalence of HAI over 8 years (trend χ2 = 2.15, P = 0.143). However, significant differences in prevalence of HAI were evident between the surveys (χ2 = 21.14, P < 0.001). The intensive care unit had the highest frequency of HAIs (24.36%) and respiratory tract infections accounted for 62.50% of all cases; Escherichia coli was the most common pathogen (16.67%). A 44.13% prevalence of antimicrobial use with a gradually decreasing trend over time was recorded. More attention should be paid to potential high-risk clinical departments and HAI types with further enhancement of rational antimicrobial use.

Threads were infected with the spores of four species of bacteria and put inside rubber gloves which were sealed into plastic bags and irradiated with electrons or gamma rays. A dose of 1·5 Mrad. killed approximately 99·99% of the spores of each species and a dose of 2·5 Mrad. appeared to give an adequate margin of safety for sterilization. Spores were similarly killed inside plastic tubing and within the lumen of hypodermic needles.

The tensile strength of the gloves decreased with increasing doses of radiation so that the rough, solution-dipped gloves tested were significantly weaker after 8·0 Mrad., but the smooth gloves tested still complied with the British Standard after 30 Mrad. When vacuum-packed before irradiation, rough gloves were still satisfactory after 16 Mrad., and smooth gloves were apparently unaffected by 30 Mrad.; they could, therefore, be sterilized six and twelve times, respectively.

Radiation gives dependable sterilization of rubber gloves, and the use of a sealed plastic package obviates subsequent contamination. The possibility of using disposable radiation-sterilized gloves is discussed, the use of a plastic radiation indicator suggested and the practical applications of radiation sterilization in the hospital considered.

Oesophageal cancer is the most common gastrointestinal malignancy in China and one of the major causes of death due to cancer worldwide. The occurrence of oesophageal cancer is a multifactor, multistage, and multistep process influenced by heredity, the environment, and microorganisms. Specifically, bacterial infection may be involved in the process of tissue carcinogenesis by directly or indirectly influencing tumour occurrence and development. Porphyromonas gingivalis is an important pathogen causing periodontitis, and periodontitis can promote the occurrence of various tumours. An increasing number of studies to date have shown that P. gingivalis plays an important role in the occurrence and development of oesophageal cancer. Overall, exploring how P. gingivalis promotes oesophageal cancer occurrence and development and how it affects the prognosis of these patients is of great importance for the diagnosis, prevention, and treatment of this type of cancer. Herein, the latest progress is reviewed.

Seven viruses isolated from outbreaks of swine vesicular disease in various countries between 1966 and 1973 were compared in pigs and infant mice. All produced a similar disease and virus excretion pattern in the pig, although the Italy/66 virus was considerably less virulent than the other viruses. The results of cross neutralization tests of convalescent pig sera and the response of 5-day-old mice to intraperitoneal inoculation indicated minor differences between some viruses. The Italy/66, Hong Kong/71 and France/73 viruses differed from each other and also from the Italy/72, England/72, Austria/73 and Poland/73 group of viruses.