Knowledge about the infection transmission routes is significant for developing effective intervention strategies. We searched the PubMed databases and identified 10 studies with 14 possible inflight influenza A(H1N1)pdm09 outbreaks. Considering the different mechanisms of the large-droplet and airborne routes, a meta-analysis of the outbreak data was carried out to study the difference in attack rates for passengers within and beyond two rows of the index case(s). We also explored the relationship between the attack rates and the flight duration and/or total infectivity of the index case(s). The risk ratios for passengers seated within and beyond the two rows of the index cases were 1.7 (95% confidence interval (CI) 0.98–2.84) for syndromic secondary cases and 4.3 (95% CI 1.25–14.54) for laboratory-confirmed secondary cases. Furthermore, with an increase of the product of the flight duration and the total infectivity of the index cases, the overall attack rate increased linearly. The study indicates that influenza A(H1N1)pdm09 may mainly be transmitted via the airborne route during air travel. A standardised approach for the reporting of such inflight outbreak investigations would help to provide more convincing evidence for such inflight transmission events.

The aim of this study was to compare the incidence of community-acquired Legionnaires' Disease in Nottingham with England and Wales and to explore reasons for any difference observed. Based on data from the National Surveillance Scheme for Legionnaires' Disease (1980–1999), the rate of infection in England and Wales was 1·3 per million/year compared with 6·6 per million/year in Nottingham. Domestic water samples were obtained from 41 (95%) of 43 Nottingham cases between 1997 and 2000. In 16 (39%) cases, Legionella sp. were cultured in significant quantities. Proximity to a cooling tower was examined using a 1[ratio ]4 case-controlled analysis. No significant difference in the mean distance between place of residence to the nearest cooling tower was noted (cases 2·7 km vs. controls 2·3 km; P=0·5). These data suggest that Nottingham does have a higher rate of legionella infection compared to national figures and that home water systems are a source.

The main aim of this study was to measure and explain geographic variations in the incidence of Legionnaires' disease in Scotland, particularly to help understand the source of non–outbreak infection.

Between 1978 and 1986 the overall mean annual incidence rate was 7·9 per million (range 3·1–20·2), and for non–outbreak, non-travel cases it was 5·6. There were geographical variations by health board, by city and within cities, e.g. the mean annual incidence rate per million for non–travel, non–outbreak disease was 1·2 in Tayside Health Board, 3·7 in Lanarkshire, 5·6 in Lothian and 14·4 in Greater Glasgow. In Greater Glasgow Health Board non–travel cases lived in and around the city centre and in some postcode sectors there, the mean annual incidence rate exceeded 100. Travel–related cases lived in peripheral areas.

These variations could not be explained by differences in access to and use of diagnostic services, surveillance, or host susceptibility (as reflected by socio–economic status and frequency of other respiratory disease). The explanation probably lay in environmental factors, though differences in agent virulence were not excluded.

The two main conclusions are, that non–outbreak cases were not truly sporadic, and that the spacetime variations in incidence support the hypothesis that cooling towers were an important source of infection for not–nravel, non-outbreak cases. If so such infection is potentially preventable.

One hundred and twenty-eight shigella strains isolated from newborn and infant human faecal specimens at Kaohsiung Medical College Hospital in Taiwan were serogrouped, serotyped and examined for drug-resistance patterns and for the presence of plasmids. Forty-seven pre cent of the isolates were found to belong to the Shigella sonnei serogroup, 41%to the S.flexneri group,9%to the S.boydii group and 3%to the S.dysenteriae group.The serotype with the greatest number of strains was S.sonnei I. (29 %) followed by S. flexneri 1 (27%). Each strain was tested for resistance to 11 antimicrobial agents. Eighty-eight per cent of the strains were resistant to tetracycline, 87% to chloramphenicol, 84% to streptomycin, 52% to ampicillin, 25% to nalidixic acid, 29% to kanamycin, 11 % to cephalothin, 11% to neomycin, 10% to cotrimoxazole, 1% to amikacin and none to gentamicin. The most prevalent resistance pattern was ApCmSmTc (28%). Clinical isolates demonstrating multiple resistance were found to harbour a large transmissible plasmid of 45–75 MDa while isolates without multiple resistance did not. Two large virulence plasmids of 123 and 110 MDa were found in 12 strains of S. flexneri and 4 strains of S. sonnei phase I. Small plasmids of 4·5, 4·2, 3·5, 2·8, 2·5. 2·0 and 1·5 MDa were also present in all strains. These small plasmids were species specific and can be used as marker plasmids to identify species.

Cryptococcosis is not a commonly diagnosed disease. Records of its occurrence in Britain are virtually non-existent before 1945. when the Mycological Reference Laboratory (MRL) of the Public Health Laboratory Service was first established

Completion of treatment is key to tuberculosis control. Using national surveillance data we assessed factors associated with tuberculosis patients being lost to follow-up before completing treatment (‘lost’). Patients reported in England, Wales and Northern Ireland between 2001 and 2007 who were lost 12 months after beginning treatment were compared to those who completed, or were still on treatment, using univariable and multivariable logistic regression. Of 41 120 patients, men [adjusted odds ratio (aOR) 1·29; 95% confidence interval (CI) 1·23–1·35], 15- to 44-year-olds (P<0·001), and patients with pulmonary sputum smear-positive disease (aOR 1·25, 95% CI 1·12–1·45) were at higher risk of being lost. Those recently arrived in the UK were also at increased risk, particularly those of the White ethnic group (aOR 6·39, 95% CI 4·46–9·14). Finally, lost patients had a higher risk of drug resistance (aOR 1·41, 95% CI 1·17–1·69). Patients at risk of being lost require enhanced case management and novel case retention methods are needed to prevent this group contributing towards onward transmission.

Vaccination programmes are considered a main contributor to the decline of infectious diseases over the 20th century. In recent years, the national vaccination coverage in the Netherlands has been declining, highlighting the need for continuous monitoring and evaluation of vaccination programmes. Our aim was to quantify the impact of long-standing vaccination programmes on notified cases in the Netherlands. We collected and digitised previously unavailable monthly case notifications of diphtheria, poliomyelitis, mumps and rubella in the Netherlands over the period 1919–2015. Poisson regression models accounting for seasonality, multi-year cycles, secular trends and auto-correlation were fit to pre-vaccination periods. Cases averted were calculated as the difference between observed and expected cases based on model projections. In the first 13 years of mass vaccinations, case notifications declined rapidly with 82.4% (95% credible interval (CI): 74.9–87.6) of notified cases of diphtheria averted, 92.9% (95% CI 85.0–97.2) cases of poliomyelitis, and 79.1% (95% CI 67.1–87.4) cases of mumps. Vaccination of 11-year-old girls against rubella averted 49.9% (95% CI 9.3–73.5) of cases, while universal vaccination averted 68.1% (95% CI 19.4–87.3) of cases. These findings show that vaccination programmes have contributed substantially to the reduction of infectious diseases in the Netherlands.

(1)Statistical evidence cannot be deduced from such a small series of cases, but it would seem that the extent to which agglutinins for B. proteus X. 19 (Weil-Felix) were formed in the blood varied directly as the severity of the illness, since with the older and more ill patients a much higher dilution of serum agglutinated the organism at or near crisis than was the case with the younger patients, who were less acutely ill. An exception to this rule was met with in one case (Mrs E. R.), whose serum did not agglutinate the organism in a dilution beyond 1: 250, although she was the most severely ill of all the patients. It is possible that failure of agglutinin-formation resembles the absence of leucocytosis in the severely ill case of pneumonia and may be regarded as a bad prognostic feature.

(2)A positive Weil-Felix reaction was not obtained before the fifth day of illness, nor in any case before the characteristic rash appeared, so that the reaction is of little value as a factor in the early diagnosis of typhus. Later, a reaction in which a dilution of the serum of 1: 50 agglutinates the organism may be regarded as diagnostic of typhus.

(3)The Weil-Felix reaction remained positive for the longest period in those cases whose serum agglutinated in highest dilution, and in these patients a positive reaction (1: 25–1: 50) was still present nine to twelve weeks after infection, whereas in the milder cases, and in Mrs E. R., the reaction became negative in six to eight weeks from the onset of illness.

(4)In view of this heterologous reaction in typhus, it is interesting to record that the Wassermann reaction obtained before crisis was positive in four out of six cases. It was still positive in two of the most severely ill patients a week after crisis, but was negative in all cases a week later.

Previous evidence has suggested an association between cryptosporidiosis and consumption of unfiltered drinking water from Loch Katrine in Scotland. Before September 2007, the water was only micro-strained and chlorinated; however, since that time, coagulation and rapid gravity filtration have been installed. In order to determine risk factors associated with cryptosporidiosis, including drinking water, we analysed data on microbiologically confirmed cases of cryptosporidiosis from 2004 to 2010. We identified an association between the incidence of cryptosporidiosis and unfiltered Loch Katrine drinking water supplied to the home (odds ratio 1·86, 95% confidence interval 1·11–3·11, P = 0·019). However, while filtration appears to be associated with initially reduced rates of cryptosporidiosis, evidence suggests it may paradoxically make those consumers more susceptible to other transmission routes in the long-term. These findings support implementation of similar treatment for other unfiltered drinking-water supplies, as a means of reducing cryptosporidiosis associated with drinking water.

1. Bacteriological examination of large samples of Perch and Powan from natural and artificial waters has shown that a considerable decline in the normal bacterial flora of the fish occurs during the summer months. Reinfection occurs when the temperature falls.

2. These variations are largely attributable to the effect of temperature upon the immunological responses of the fish.

3. The bacteria concerned appear to be water bacteria, which invade the muscles and body cavity of the fish, as well as the gill and gut-content.

4. The degree of infection is also influenced by the bacterial content of the water.

1. The term “paratyphoid group of bacilli” has been confined in the present enquiry to those strains which in their cultural characters and agglutination reactions are indistinguishable from B. suipestifer and B. paratyphosus (B). B. enteritidis Gaertner and B. paratyphosus (A) are excluded.

2. The strains of bacilli belonging to the “paratyphoid” group can be separated into two classes by means of the absorption method, namely one group identical with recognised, standard strains of B. suipestifer and one identical with standard strains of B. paratyphosus (B); and we regard these two bacilli as separate organisms.

3. In our experience, B. suipestifer has been found only in food or in outbreaks of acute illness attributable to food-poisoning, whereas B. paratyphosus (B) has been found in cases of paratyphoid fever or in persistent paratyphoid “carriers.”.

4. We are disposed to put forward the suggestion indicated by these observations, that these two organisms have a different distribution in nature, the normal habitat of B. suipestifer being the alimentary canal of the pig (and other animals) and of food derived from such animals, whereas the normal habitat of B. paratyphosus (B) is the human alimentary tract (including the gall-bladder).

5. The examination of cultures from the faeces and urine of 300 typhoid convalescents was completely negative, neither B. suipestifer nor B. paratyphosus (B) being obtained. These observations confirm those of other writers, and, apart from carrier cases, the occurrence of B. paratyphosus (B) in healthy human beings appears to be unknown in this country.

Our thanks are due to Drs Fisher, Trautmann, Uhlenhuth, Williams, Rommeler, Prigge, Schern, Friedrichs, Savage and Fowler, who have very kindly supplied us with strains of bacilli for investigation.

1. The Tworts' potency measures correlate highly with all the reasonable alternative single measures of potency which have been examined.

1. Section A of this report is introductory; Section B deals with the correlations between the Tworts' measures of carcinogenic potency and certain alternative measures, and their use in testing the significance of differences between the potencies of different oils. Section C deals with the relation of potency to physical characteristics and place of origin of the oil. Section D deals with the relations between the saturation, refractivity, carcinogenic potency and place of origin of oils.

This paper applies a scenario planning approach, to outline some current uncertainties related to COVID-19 and what they might mean for plausible futures for which we should prepare, and to identify factors that we as individual faculty members and university institutions should be considering now, when planning for the future under COVID-19. Although the contextual focus of this paper is Canada, the content is likely applicable to other places where the COVID-19 epidemic curve is in its initial rising stage, and where universities are predominantly publicly funded institutions.

In a prison in Victoria, Australia, our objectives were contact tracing of inmates and staff at risk of exposure to an identified index case; and to determine risk factors for prevalent and incident infection. Inmates and staff who were potentially exposed to the index case were screened with a Mantoux skin test and a questionnaire. Inmate movements within the prison were compared to movements of the index case. Logistic regression was used to determine risk factors for infection. The index case had smear positive, cavitating pulmonary tuberculosis (TB), which was undiagnosed for 3 months. This was the period of potential exposure. The prevalence of positive skin test reactions in 190 inmates and staff at the prison was 10%. Significant predictors of a positive skin test were being an inmate (odds ratio (OR) 15·5), older age (OR 8·3) and being born overseas (OR 10·7). Bacille Calmette Guerin (BCG) vaccination, proximity to the index case in various prison sites, duration of incarceration, number of incarcerations and number of inmates per cell were not significant. There were three recent skin test conversions from negative to positive, representing a conversion rate of 3·5%. We did not find evidence of significant transmission of TB from a single index case. The prevalence of infection in this Australian prison was lower than published rates in other countries. Better prison conditions and different demographics of prison inmates in Australia may explain these differences.

1. Rickettsia burneti has been isolated from the tick Haemaphysalis punctata collected from sheep in an endemic area of Q fever in south-east England.

2. Isolation from one batch may have been due to contamination from the wool of sheep excreting R. burneti, but evidence is presented that isolation from another batch was due to the presence of the rickettsia in the tick tissues.

We should like to express our gratitude to Mr R. D. Brown, M.R.C.V.S., Mr F. L. J. Kett, F.R.E.S., and Mr J. Carey, who helped to collect the specimens. We are also indebted to Dr A. D. Lees (Agricultural Research Council Unit of Insect Physiology) for his help with the identification of the ticks. Finally we wish to acknowledge the valuable laboratory assistance given by Mr P. C. Collings, Miss Z. Page and Miss K. Arnold.

Hand-foot-mouth disease (HFMD) is a frequently occurring epidemic and has been an important cause of childhood mortality in China. Given the disease's significant impact nationwide, the epidemiological characteristics and spatio-temporal clusters in Fuyang from 2008 to 2013 were analysed in this study. The disease exhibits strong seasonality with a rising incidence. Of the reported HFMD cases, 63·7% were male and 95·2% were preschool children living at home. The onset of HFMD is age-dependent and exhibits a 12-month periodicity, with 12-, 24- and 36-month-old children being the most frequently affected groups. Across the first 60 months of life, children born in April [relative risk (RR) 8·18], May (RR 9·79) and June (RR 8·21) exhibited an elevated infection risk of HFMD relative to January-born children; the relative risk compared with the reference (January-born) group was highest for children aged 24 months born in May (RR 34·85). Of laboratory-confirmed cases, enterovirus 71 (EV71), coxsackie A16 (Cox A16) and other enteroviruses accounted for 60·1%, 7·1% and 32·8%, respectively. Spatio-temporal analysis identified one most likely cluster and several secondary clusters each year. The centre of the most likely cluster was found in different regions in Fuyang. Implications of our findings for current and future public health interventions are discussed.

The epidemiology of West Nile virus (WNV) in Israel is different from other neighbouring countries in the Middle East where disease burden has been minimal. We analysed a cohort of Ashkenazi Jewish patients with symptomatic WNV infection (n = 39), and WNV-negative controls (n = 61), for nine genetic variants that has been suggested to be associated with susceptibility to WNV. Two single nucleotide polymorphisms were significantly more frequent in WNV-infected than non-infected individuals, rs7280422 (MX1) [odds ratio (OR) 4·05, 95% confidence interval (CI) 2·04–8·03, P < 0·001] and rs3213545 (OASL) (OR 1·85, 95% CI 1·03–3·3, P = 0·03). Genetic polymorphism may play a significant role in susceptibility to WNV infection in Ashkenazi Jews

1. In many parts of the Caribbean there is a high mortality between 6 months and 2 years due to malnutrition and gastro-enteritis. These two conditions are so closely inter-connected that they can conveniently be regarded as a single syndrome, for which the term ‘weanling diarrhoea’ has recently been suggested. The clinical picture revealed by visits to children's wards was in line with the vital statistics.

2. The prevalence of malnutrition and gastro-enteritis in infants and young children is the result of child-feeding practices characteristic of the area. The duration of breast-feeding is shorter than in Africa and Asia. After 3 months or so breast-feeding, if it does not cease altogether, becomes partial, and in general there is a steady change in the direction of less breast milk. In some territories weaning at an even earlier stage in infancy seems to result in the common occurrence of malnutrition in infants under 6 months of age.

3. The foods given to supplement or replace breast milk include processed cow's milk, starch roots and fruits and cereals. Imported processed milk supplies good quality protein otherwise lacking in the child's diet, but the use of expensive proprietory infant milk foods, out of line with family purchasing power and given in over-diluted form, is among the causes of malnutrition. The use in infant and child feeding of dried skim milk-much the cheapest kind of milk in terms of nutritive value-is increasing and this trend should be encouraged.

4. Most of the malnutrition is of the ‘marasmic’ type. Classical kwashiorkor, now comparatively rare, was seen more often 5–10 years ago.

5. It is suggested that the conventional practice of grouping deaths in the periods 0 to 1 and 1 to 4 has, in the Caribbean and other developing areas, retarded recognition of the importance of malnutrition and gastro-enteritis as the principal cause of death during and after the weaning period. The analysis of mortality statistics according to shorter age intervals is desirable.

6. Further studies and action are recommended concerned with the following: the continuing analysis of mortality and morbidity statistics to elicit relationships with malnutrition; child feeding practices in the different territories; the social and economic background of individual victims of malnutrition and of the feeding errors responsible for their condition; improvement in the treatment of malnourished children; the scope and efficiency of maternal and child health services; the distribution of dried skim milk and its extension.

7. The establishment of a Caribbean Nutrition Centre will contribute to the prevention of malnutrition and help in solving long-term problems of food supply and nutrition in the area.

Cellulitis is a common infection of the skin and soft tissue. Susceptibility to cellulitis is related to microorganism virulence, the host immunity status and environmental factors. This retrospective study from 2001 to 2013 investigated relationships between the monthly incidence rate of cellulitis and meteorological factors using data from the Taiwanese Health Insurance Dataset and the Taiwanese Central Weather Bureau. Meteorological data included temperature, hours of sunshine, relative humidity, total rainfall and total number of rainy days. In otal, 195 841 patients were diagnosed with cellulitis and the incidence rate was strongly correlated with temperature (γS = 0.84, P < 0.001), total sunshine hours (γS = 0.65, P < 0.001) and total rainfall (γS = 0.53, P < 0.001). The incidence rate of cellulitis increased by 3.47/100 000 cases for every 1° elevation in environmental temperature. Our results may assist clinicians in educating the public of the increased risk of cellulitis during warm seasons and possible predisposing environmental factors for infection.

Historical survey data suggest that the seroprevalence of antibodies against Coxiella burnetii in the general population of The Netherlands decreased from more than 40% in 1983 to 2·4% in 2007, just before the start of the large 2007–2010 Q fever epidemic. To assess whether the sharp decline in seroprevalence was real, we performed a cross-sectional study using historical samples. We tested samples using a contemporary commercial indirect immunofluorescence assay. In plasma samples from the south of The Netherlands from 1987, we found an age- and sex-standardized seroprevalence of 14·4% (95% confidence interval 11·2–18·3). This was significantly lower than a 1983 estimate from the same area (62·5%), but significantly higher than 2008 (1·0%) and 2010 (2·3%) estimates from the same area. The study suggests that there was a steady and sharp decline in Q fever seroprevalence in the south of The Netherlands from 1987 to 2008. We assume that seroprevalence has decreased in other parts of The Netherlands as well and seroprevalence surveys in other European countries have shown a similar declining trend. Waning population immunity in The Netherlands may have contributed to the scale of the 2007–2010 Q fever epidemic. For a better understanding of the infection dynamics of Q fever, we advocate an international comparative study of the seroprevalence of C. burnetii.