Pneumonia is one of the leading causes of hospitalisations among adults in the USA. Individuals with diabetes mellitus (DM) have been associated with increased risk for pneumonia and complications including death. The objectives of this study were to (1) compare the prevalence and healthcare utilisation patterns for pneumonia in individuals with and without DM, and (2) identify risk factors for pneumonia in those with DM. We performed a retrospective, cross-sectional analysis of the US adult population using Medical Expenditure Panel Surveys (MEPS) data from 2014. Overall, the data represented 24 million individuals with DM and 218 million without DM in the USA. The population-based rate for a pneumonia event was 34 per 1000 persons for individuals with DM and 19 per 1000 persons without DM. Compared to the non-DM group, individuals with DM were treated 1.8x, 2.6x and 1.4x more in the ED, hospital and outpatient, respectively. Furthermore, the average cost per pneumonia event was significantly higher among individuals with DM compared to non-DM in the inpatient setting ($11 931 vs. $7751; P < 0.001). Among individuals with DM, female sex, DM complications, smokers and administration of pneumococcal vaccines were significant factors associated with a pneumonia event.

Dengue haemorrhagic fever (DHF) is caused by dengue virus transmitted by Aedes mosquitoes; mean age of patients varies temporally and geographically. Variability in age of patients may be due to differences in transmission intensity or demographic structure. To compare these two hypotheses, the mean age of DHF patients from 90 districts in northern Thailand (1994–1996, 2002–2004) was regressed against (i) Aedes abundance or (ii) demographic variables (birthrate, average age) of the district. We also developed software to quantify direction and strength of geographical gradients of these variables. We found that, after adjusting for socioeconomics, climate, spatial autocorrelation, the mean age of patients was correlated only with Aedes abundance. The geographical gradient of mean age of patients originated from entomological, climate, and socioeconomic gradients. Vector abundance was a stronger determinant of mean age of patients than demographic variables, in northern Thailand.

We investigated a large gastroenteritis outbreak that occurred in Northern Greece in 2019. A case was defined as anyone presenting with diarrhoea and/or vomiting from 24 January 2019 to 04 February 2019. We conducted a case-control study (CCS) using random selection of participants >16 years of age, residents of town X, who visited the health care centre between 25 and 28 January 2019. Moreover, we conducted a retrospective cohort study (CS) at the four elementary schools of the town. We collected clinical and water samples and the water supply system was inspected. In total, we recorded 638 cases (53% female; median age was 44 years (range 0–93)). Forty-eight cases and 52 controls participated in the CCS and 236 students in the CS. Both CCS and CS indicated tap water as the most likely source (OR 10, 95% CI 2.09–93.4, explaining 95.7% of cases; RR = 2.22, 95% CI 1.42–3.46, respectively). More than one pathogen was detected from stool samples of 6 of the 11 cases tested (norovirus, Campylobacter jejuni, Enterohemorrhagic E. coli (EHEC) and Enteropathogenic E. coli (EPEC)). Water samples, collected after ad-hoc chlorination, tested negative. Technical failures of the water tanks' status were identified. Our results suggested a waterborne outbreak. We recommended regular monitoring of the water supply system and immediate repair of technical failures.

In an inter-laboratory survey, 148 samples of cooked prawns and shrimps were obtained at the point of sale to the consumer. Salmonellae and Vibrio parahaemolyticus were not detected. Yersinia enterocolitica was isolated from three samples. Results for total viable count and presence of Escherichia coli and Staphylococcus aureus complied well with available guidelines for imported cooked prawns, suggesting that the risk of food poisoning from retail samples of these foods in the South of England is minimal.

1. An account is given of the finding of 19 symptomless excreters of Salm. typhi and of 15 incubating cases (‘precocious carriers’) in the course of repeated examination of the faeces of 435 staff and patients at the hospital.

2. In a comparison of the frequency of isolation of Salm. typhi from the faeces it was found that the the selenite F enrichment method was more efficient than enrichement in Kauffmann 's tetrathionate broth, and that both methods were superior to direct plating on desoxycholate citrate agar.

3. Examination of sera from cases of typhoid fever showed that, in some cases, H- and O-agglutinin titres which would normally be regarded as ‘diagnostic’ may be reached well within the first week of illness.

4. Measures are described which were taken to exclude connexion between this outbreak and (a) a chronic carrier found during investigation of the hospital milk supply, and (b) the incidence of typhoid fever at another hospital.

5. A case of typhoid fever at Shrewsbury is described which was probably infected by an abortive missed case. Attempts to make a retrospective bacteriological or serological diagnosis of the latter were unsuccessful.

6. An account is given of the use of the sewage-pad method in an attempt to trace the source of infection in the case of a sewer worker who developed typhoid fever 14 months after the main epidemic and was probably infected by an intermittent carrier at the hospital.

The protection afforded by a combined enteric and cholera vaccine administered by the intradermal route, and demonstrated by active and passive mouse protection tests and agglutination titres, is excellent and equal to that given individually by the component TAB and cholera vaccines.

In order to reduce the number of injections required and the unpleasant reactions provoked it is suggested that combined enteric and cholera vaccine administered by the intradermal route is of value, where appropriate, for the vaccination of travellers, and for the rapid protection of non-immune persons in the event of natural disasters or mobilization.

Infections caused by extended-spectrum β-lactamase-producing Enterobacteriaceae (ESBL-E) have become increasingly prevalent, posing a serious public threat worldwide. It is commonly believed that untreated urinary tract infections (UTI) and asymptomatic bacteriuria (ABU) during pregnancy are associated with poor obstetric outcomes. Currently, there is a paucity of data regarding the outcomes or risk factors of such ESBL-E infections in pregnant women. We conducted a retrospective 1:2 matched case–control study of hospitalised pregnant women with ESBL-E- vs. non-ESBL-producing Enterobacteriaceae-positive urine cultures obtained between 2004 and 2015, and compared risk factors for the development of resistant bacteria, clinical course and outcomes. In total, 87 pregnant women with ESBL-E-positive urine cultures were matched to 174 controls by decade of age, ethnicity and pregnancy trimester. Significant risk factors for acquisition of ESBL-E included prior UTI/ABU episodes (50.6% vs. 26.3%, P < 0.001), previous isolation of ESBL-E in urine cultures (12.6% vs. 0.6%, P < 0.001) and prior antibiotic exposure (71.3% vs. 54%, P = 0.002). Previous hospitalisation, however, was not found to be a risk factor. No significant difference was found in adverse obstetric outcomes. We conclude that prior urinary infections and antibiotic exposure were significant risk factors for the isolation of ESBL-E pathogens from the urine of pregnant women; however, this was not associated with worse obstetric outcomes compared with non-ESBL-E pathogens.

This paper compares strains of foot-and-mouth disease (FMD) serotype SAT (South African Territories) 2 viruses isolated from Zimbabwe and other African countries using monoclonal antibodies (MAb). A sandwich-ELISA was used to examine the relative binding of anti-SAT 2 MAb to the various viruses. The MAb-binding profiles of viruses isolated from field samples were compared using hierarchical cluster analysis. Viruses were obtained from game animals, mainly African buffalo (Syncerus caffer) which is the natural host and reservoir for SAT serotypes in Africa, and from cattle showing clinical signs of FMD, as well as from animals suspected of carrying the virus subclinically. Some isolates have been adapted for use as vaccine strains. The results showed that most of the Zimbabwe isolates collected between 1989 and 1992 were an antigenically closely-related group. Although differences were observed between Zimbabwe isolates collected between 1989 and 1992 and those collected in 1987, there was no correlation with the different MAb binding patterns within the 1987 group and the epidemiological information received from the field. Similar profiles were observed for many SAT 2 viruses, including viruses isolated over a 50-year period and from geographically distant areas. This indicates an inherent stability in antigenic profiles of SAT 2 viruses. The MAb panel was capable of assessing antigenic variation, since very different profiles were obtained for some isolates. The work also allowed comparison and characterization of anti-type SAT 2 MAb from different laboratories. The findings are discussed with reference to selection of vaccine strains.

Rabies is one of the major public health problems in China, and the mortality rate of rabies remains the highest among all notifiable infectious diseases. A meta-analysis was conducted to investigate the post-exposure prophylaxis (PEP) vaccination rate and risk factors for human rabies in mainland China. The PubMed, Web of Science, Chinese National Knowledge Infrastructure, Chinese Science and Technology Periodical and Wanfang databases were searched for articles on rabies vaccination status (published between 2007 and 2017). In total, 10 174 human rabies cases from 136 studies were included in this meta-analysis. Approximately 97.2% (95% confidence interval (CI) 95.1–98.7%) of rabies cases occurred in rural areas and 72.6% (95% CI 70.0–75.1%) occurred in farmers. Overall, the vaccination rate in the reported human rabies cases was 15.4% (95% CI 13.7–17.4%). However, among vaccinated individuals, 85.5% (95% CI 79.8%–83.4%) did not complete the vaccination regimen. In a subgroup analysis, the PEP vaccination rate in the eastern region (18.8%, 95% CI 15.9–22.1%) was higher than that in the western region (13.3%, 95% CI 11.1–15.8%) and this rate decreased after 2007. Approximately 68.9% (95% CI 63.6–73.8%) of rabies cases experienced category-III exposures, but their PEP vaccination rate was 27.0% (95% CI 14.4–44.9%) and only 6.1% (95% CI 4.4–8.4%) received rabies immunoglobulin. Together, these results suggested that the PEP vaccination rate among human rabies cases was low in mainland China. Therefore, standardised treatment and vaccination programs of dog bites need to be further strengthened, particularly in rural areas.

Tularaemia is a zoonotic disease, in Europe caused by Francisella tularensis subsp. holarctica. Many lagomorphs and a variety of small rodents are wildlife species prone to develop clinical disease, while predators and scavengers are relatively resistant and may serve as sentinels. Blood samples from 656 Swedish wild predators and scavengers were serologically investigated using slide agglutination and microagglutination. In the slide agglutination test, 34 seropositive animals were detected, and they were found among all species investigated: brown bear (Ursus arctos), Eurasian lynx (Lynx lynx), raccoon dog (Nyctereutes procyonoides), red fox (Vulpes vulpes), wild boar (Sus scrofa), wolf (Canis lupus) and wolverine (Gulo gulo). Due to haemolysis the microagglutination test was more difficult to read at low titres, and only 12 animals were classified as seropositive. F. tularensis subsp. holarctica was detected by a polymerase chain reaction in lymphatic tissues of the head in one brown bear, one red fox and one wolf. The significance of this finding regarding possible latency of infection is not clear. In conclusion, the results of this study indicate that all predator and scavenger species included in this study may serve as sentinels for tularaemia in Sweden. Their role as reservoirs is unclear.

I. Life-Cycle. Colony Formation, Sporing, Papilla Formation.

If any bacterium is sown in the usual way from a fluid suspension on to a plate of suitable culture medium, colonies arise from the multiplication of single bacteria. These colonies grow at their margins ar a rate roughly constant for the species. When the colony has reached a certain size, which is again roughly constant for the species, it ceases to grow or continues growing very slowly. Thus for example colonies of streptococci grow to 1 mm. in diameter, those of coliforms to 3 or 6 mm. The colonies do not continue to grow until they have covered the whole plate. This limitation of growth is not due to the using up of the food supply or to the drying of the medium, since, if a second sowing of the same bacterium is made between the arrested colonies, a new crop of colonies arises.

1 Twort (1907) obtained lactose fermenting variants of B. typhosus after prolonged growth in this sugar. These variations do not however occur frequently and regularly. They are probably examples of mutation from a homozygous strain (Mode A above).

2 The variations mentioned take place in culture where their origin from papillae can be seen. It is likely that exaltation of virulence is an adaptive variation of the same kind occurring in a host.

Norovirus is a predominant cause of infectious gastroenteritis in countries worldwide [1–5]. It accounts for approximately 50% of acute gastroenteritis (AGE) and >90% of viral gastroenteritis outbreaks [6, 7]. The incubation period ranges between 10 and 48 h and illness duration is generally 1–3 days with self-limiting symptoms; however, this duration is often longer (e.g. 4–6 days) in vulnerable populations such as hospital patients or young children [2, 8]. Symptomatic infection of norovirus presents as acute vomiting, diarrhoea, abdominal cramps and nausea, with severe vomiting and diarrhoea (non-bloody) being most common [2, 5, 9].

Measles is a highly infectious human viral disease caused by measles virus (MeV). An estimated 114 900 measles deaths occurred worldwide in 2014. There are currently eight clades (A–H) comprised 24 MeV genotypes. We sought to characterise MeVs among Central African Republic (CAR) refugees during the 2014 measles epidemic in Cameroon. Samples were collected from children <15 years with suspected measles infections in two refugee camps in the east region of Cameroon. Viral RNA was extracted directly from urine samples. RNA detection of MeV RNA was performed with real-time reverse transcription polymerase chain reaction (PCR) to amplify a 634 bp nucleotide fragment of the N gene. The sequence of the PCR product was obtained to determine the genotype. MeV RNA was detected in 25 out of 30 samples from suspected cases, and among the 25 positive samples, MeV sequences were obtained from 20. The MeV strains characterised were all genotype B3. The MeV strains from genotype B3 found in this outbreak were more similar to those circulating in Northern Cameroon in 2010–2011 than to MeV strains circulating in the CAR in 2011. Surveillance system should be improved to focus on refugees for early detection of and response to outbreaks.

The purposes of the study were (i) to describe the abundance and epidemiology of Legionellaceae in the man-made environment in a northern Italian area, (ii) to assess the concordance between pulsed-field gel electrophoresis (PFGE) and automated ribotyping (AR) techniques for genotyping L. pneumophila and (iii) to investigate the correlation between serogrouping and genotyping data. Water was sampled from reservoirs in 12 buildings across an area of 80-km radius. Despite the water temperature always being maintained above 55 °C, all of the buildings sampled were contaminated with Legionellaceae on at least one occasion and 63 L. pneumophila isolates representing nine different serogroups were collected. The two DNA methods revealed a high degree of genetic heterogeneity, even though identical L. pneumophila clones were recovered at different sites. The AR technique provided a fairly reliable approximation of PFGE results (73% concordance), however there was poor correlation between serogrouping and genotyping data as identical DNA fingerprints were shared by isolates of different serogroups.

The objective of this study was to examine temporal and regional variations of sporadic Creutzfeldt–Jakob disease (sCJD) in a retrospective study using Japanese national surveillance data from 2001 to 2010. We calculated the incidence of sCJD by age and sex, derived the standardized incidence in each of the 47 prefectures, and performed spatial disease clustering analysis. The average annual incidence of sCJD was 1·026 per million in men (637 patients) and 1·132 per million in women (733 patients), a significant sex difference after adjustment for age (P = 0·001). The ratios of familial CJD to sCJD apparently increased between 2001–2005 and 2006–2010, possibly as a result of the nationwide introduction of genetic testing after 2006. Based on the data of 2006–2010, certain geographical clusters of sCJD were identified. The incidence of sCJD was higher in several specific prefectures compared to the national average. Thus, sCJD appears to have regional variations, suggesting the existence of genetic or region-specific factors affecting the incidence of the disease.

An outbreak of food poisoning caused by Salmonella typhi-murium, phage-type 12, in which 122 persons were infected, is described.

Isolation of the same organism from the drains of two large abattoirs, from pig faeces at one abattoir, and from the floor drains of fifteen out of fifty-four butchers' shops and bakehouses examined, together with records showing that this organism had been recently isolated from pigs and cattle in the neighbourhood, suggested that meat was the vehicle of infection.

We are indebted to Dr E. S. Anderson and the staff of the Central Enteric Reference Laboratory and Bureau, Colindale, for phage-typing the cultures of S. typhi-murium.

We should like to thank Prof. Scott Thomson for his encouragement and advice in the preparation of this paper and Mr J. Morgan and Mr B. M. Jones of the Public Health Laboratory, Cardiff, for their technical assistance.

Polyoma virus was recovered from the air of an animal laboratory housing mice infected with the virus. Air samples were obtained by means of a high volume air sampler and further concentrated by high speed centrifugation. Total concentration of the air samples was 7·5 × 107. Assay for polyoma virus was by mouse antibody production tests. Airborne polyoma virus was detected in four of six samples.

The cytopathogenicity of 22 Legionella pneumophila isolates from 17 hospitals was determined by assessing the dose of bacteria necessary to produce 50% cytopathic effect (CPED50) in U937 human-derived macrophages. All isolates were able to infect and grow in macrophage-like cells (range log10 CPED50: 2·67–6·73 c.f.u./ml). Five groups were established and related to the serogroup, the number of PFGE patterns coexisting in the same hospital water distribution system, and the possible reporting of hospital-acquired Legionnaires' disease cases. L. pneumophila serogroup 1 isolates had the highest cytopathogenicity (P=0·003). Moreover, a trend to more cytopathogenic groups (groups 1–3) in hospitals with more than one PFGE pattern of L. pneumophila in the water distribution system (60% vs. 17%) and in hospitals reporting cases of hospital-acquired Legionnaires' disease (36·3% vs. 16·6%) was observed. We conclude that the cytopathogenicty of environmental L. pneumophila should be taken into account in evaluating the risk of a contaminated water reservoir in a hospital and hospital acquisition of Legionnaires' disease.

An alternative way to estimate the endemic level of malaria amongst Brazilian indians is proposed. This is achieved by estimating the age-related “force of infection’ of malaria (the effective inoculation rate), applying a mathematical model, described elsewhere, to serological data. In addition we present a way to estimate the Basic Reproductive Rate of malaria in the same area. The results have shown a good degree of accuracy in describing the endemic pattern of malaria in the area, and also indicate some relevant aspects of its age distribution related to the design of control strategies.

In Greece the public health surveillance for most infectious diseases, including shigellosis, is not well developed. However, four waterborne outbreaks of shigellosis have been recorded in Greece in the last three decades, in different areas of the country, under different environmental and socioeconomic conditions. This study presents the epidemiological characteristics of these four outbreaks in order to examine common points and differences and to investigate their possible association with environmental and socioeconomic conditions. All four outbreaks were caused by Shigella sonnei and related to drinking water. Epidemic curves, distribution of cases by age and gender, hospitalization rates, environmental conditions and laboratory results were compared. The outbreaks seemed to correspond to two different ‘models’ presenting two characteristic types of epidemic waves related to specific environmental conditions. The attack rates for the general population varied from about 9 to 13% and were similar for both sexes. Children were affected mostly. In these outbreaks there was a strong suspicion of contamination of the water distribution system from the sewage network, highlighting the importance of environmental health control measures.