Pneumonia is one of the most common infectious diseases with a high mortality, especially in the elderly population. To date, there have been only a few population-based studies dealing with the incidence of pneumonia in nursing homes (NHs). We conducted a cohort study using data from a large German statutory health insurance fund. Between 2010 and 2014, 127 227 NH residents 65 years and older were analysed. For the calculation of incidences per 100 person-years (PY) and 95% confidence intervals (CIs), we assessed the first diagnosis of pneumonia during the time in NH. We compared the rates between sexes, age groups, care levels, and comorbidities and we performed a multivariate Cox regression analysis. The mean age in the cohort was 84.0 years (74.6% female). A total of 19 183 incident cases led to an overall 5-year-incidence of 11.8 per 100 PY (95% CI 11.7–12.0). The incidence in men was substantially higher than in women. Rates were highest in the first month after NH placement. Our study revealed that the incidence of pneumonia is high in German NH residents and especially in males. Due to demographic changes, pneumonia will likely be increasingly relevant in the health care of the elderly and institutionalised population.

The results of this investigation may be summarised as follows:

1. The qx or cage-age mortality curve of a herd increases rapidly to a maximum and thereafter descends to an approximately constant level which is much above the level of the qx for normal mice of ages within the range of real, physiological, age of animals living in the herds.

2. At the latest ages under observation the principal factor of mortality is still the specific factor, so that the advantage produced by selective mortality and active immunisation is brought to a standstill far above the zero line. Exposure in a herd under the conditions of these experiments will not produce an ultimate population fully resistant to the specific factor of infection.

3. It is probable that a large proportion, perhaps a majority, of the members of a herd become infected early in herd life, and gradually increase their degree of immunity because variations of environmental conditions, so far as these are measured by the general herd mortality, become less and less influential on the ultimate mortality of the exposed to risk the later the point in time chosen for measurement.

4. Study of the form of the age-mortality curve is still proceeding; at present we cannot offer an adequate mathematical description of it which takes due account of the biological factors requiring attention.

5. Quite provisionally, we attribute the difference in time of the maxima of the qx curves of Pasteurella and aertrycke epidemics to a difference of average interval between infection and death.

Our purpose was to determine the effectiveness and harms of vaccination in patients with any sexual history to prevent the prevalence of papillomavirus infection. A search strategy was conducted in the MEDLINE, CENTRAL, EMBASE and LILACS databases. Searches were also conducted in other databases and unpublished literature. The risk of bias was evaluated with the Cochrane Collaboration's tool. Analysis of fixed effects was conducted. The primary outcome was the infection by any and each human papillomavirus (HPV) genotype, serious adverse effects and short-term adverse effects. The measure of the effect was the risk difference (RD) with a 95% confidence interval (CI). The planned interventions were bivalent vaccine/tetravalent/nonavalent vs. placebo/no intervention/other vaccines. We included 29 studies described in 35 publications. Bivalent HPV vaccine offers protection against HPV16 (RD −0.05, 95% CI −0.098 to −0.0032), HPV18 (RD −0.03, 95% CI −0.062 to −0.0004) and HPV16/18 genotypes (RD of −0.1, 95% CI −0.16 to −0.04). On the other side, tetravalent HPV vaccine offered protection against HPV6 (RD of −0.0500, 95% CI −0.0963 to −0.0230), HPV11 (RD −0.0198, 95% CI −0.0310 to −0.0085). Also, against HPV16 (RD of −0.0608, 95% CI −0.1126 to −0.0091) and HPV18 (RD of −0.0200, 95% CI −0.0408 to −0.0123). There was a reduction in the prevalence of HPV16, 18 and 16/18 genotypes when applying the bivalent vaccine, with no increase in adverse effects. Regarding the tetravalent vaccine, we found a reduction in the prevalence of HPV6, 11, 16 and 18 genotypes, with no increase in adverse effects.

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

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

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

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

An outbreak of Legionnaires' disease occurred in an inner city district in Calgary, Canada. This outbreak spanned a 3-week period in November–December 2012, and a total of eight cases were identified. Four of these cases were critically ill requiring intensive care admission but there was no associated mortality. All cases tested positive for Legionella pneumophila serogroup 1 (LP1) by urinary antigen testing. Five of the eight patients were culture positive for LP1 from respiratory specimens. These isolates were further identified as Knoxville monoclonal subtype and sequence subtype ST222. Whole-genome sequencing revealed that the isolates differed by no more than a single vertically acquired single nucleotide variant, supporting a single point-source outbreak. Hypothesis-based environmental investigation and sampling was conducted; however, a definitive source was not identified. Geomapping of case movements within the affected urban sector revealed a 1·0 km common area of potential exposure, which coincided with multiple active construction sites that used water spray to minimize transient dust. This community point-source Legionnaires' disease outbreak is unique due to its ST222 subtype and occurrence in a relatively dry and cold weather setting in Western Canada. This report suggests community outbreaks of Legionella should not be overlooked as a possibility during late autumn and winter months in the Northern Hemisphere.

Since 2004, efforts to improve poliovirus detection have significantly increased the volume of specimen testing from acute flaccid paralysis (AFP) patients in India. One option to decrease collection and testing burden would be collecting only a single stool specimen instead of two. We investigated stool specimen sensitivity for poliovirus detection in India to estimate the contribution of the second specimen. We reviewed poliovirus isolation data for 303984 children aged <15 years with AFP during 2000–2010. Using maximum-likelihood estimation, we determined specimen sensitivity of each stool specimen, combined sensitivity of both specimens, and sensitivity added by the second specimen. Of 5184 AFP patients with poliovirus isolates, 382 (7·4%) were identified only by the second specimen. Sensitivity was 91·4% for the first specimen and 84·5% for the second specimen; the second specimen added 7·3% sensitivity, giving a combined sensitivity of 98·7%. Combined sensitivity declined, and added sensitivity increased, as the time from paralysis onset to stool collection increased (P = 0·032). The sensitivity added by the second specimen is important to detect the last chains of poliovirus transmission and to achieve certification of polio eradication. For sensitive surveillance, two stool specimens should continue to be collected from each AFP patient in India.

In the incidence patterns of cholera, diphtheria and croup during the past when they were of epidemic proportions, we document a set of cycles (periods), one of which was reported and discussed by A. L. Chizhevsky in the same data with emphasis on the mirroring in human disease of the ∼11-year sunspot cycle. The data in this study are based on Chizhevsky's book The Terrestrial Echo of Solar Storms and on records from the World Health Organization. For meta-analysis, we used the extended linear and nonlinear cosinor. We found a geographically selective assortment of various cycles characterizing the epidemiology of infections, which is the documented novel topic of this paper, complementing the earlier finding in the 21st century or shortly before, of a geographically selective assortment of cycles characterizing human sudden cardiac death. Solar effects, if any, interact with geophysical processes in contributing to this assortment.

This study analysed the epidemiological characteristics of imported cases of acute infectious diseases and compared these features by nationality in 25 border counties of Yunnan Province from 2008 to 2017 to inform prevention strategies. Surveillance data for the imported cases collected in the border counties were analysed to determine disease variety, seasonal patterns, infection site and personal demographics and these features were compared by patient nationality. A total of 12 820 imported cases were reported in the 25 border counties, with 5610 foreign cases and 7210 native cases. The disease spectrum was more diverse among foreign cases than among native cases. Both foreign and native cases were mostly imported from Myanmar. The shift in the number of foreign cases was greater than that of native cases after 2016. Ruili, a city, that shares a border with Myanmar, exhibited the greatest number of imported infections. Farmers, businessmen, women and preschool children were frequently diagnosed with infections. Multiple prevention strategies including disease screening at the border, health education before departure and health service provision to foreigners should be carried out to reduce the risk of autochthonous spreading and to avoid potential outbreaks. Furthermore, international collaboration in terms of sharing infectious disease data should be improved between China and neighbouring countries.

Increased population movements and increased mobility made it possible for severe acute respiratory syndrome coronavirus 2, which is mainly spread by respiratory droplets, to spread faster and more easily. This study tracked and analysed the development of the coronavirus 2019 (COVID-19) outbreak in the top 100 cities that were destinations for people who left Wuhan before the city entered lockdown. Data were collected from the top 100 destination cities for people who travelled from Wuhan before the lockdown, the proportion of people travelling into each city, the intensity of intracity travel and the daily reports of COVID-19. The proportion of the population that travelled from Wuhan to each city from 10 January 2020 to 24 January 2020, was positively correlated with and had a significant linear relationship with the cumulative number of confirmed cases of COVID-19 in each city after 24 January (all P < 0.01). After the State Council launched a multidepartment joint prevention and control effort on 22 January 2020 and compared with data collected on 18 February, the average intracity travel intensity of the aforementioned 100 cities decreased by 60−70% (all P < 0.001). The average intensity of intracity travel on the nth day in these cities during the development of the outbreak was positively related to the growth rate of the number of confirmed COVID-19 cases on the n + 5th day in these cities and had a significant linear relationship (P < 0.01). Higher intensities of population movement were associated with a higher incidence of COVID-19 during the pandemic. Restrictions on population movement can effectively curb the development of an outbreak.

1. It has been shown that cows infected with brucellosis of the udder can usually be detected by an application of a modified milk ring test, based on the finding that milks from infected cows, in addition to showing a high bulk MRT titre also show considerable quarter variations. The effects of adult vaccination with strain 19 vaccine on the MRT are reported; low bulk titres with uniformity between quarters, except at the beginning and end of lactation and immediately following vaccinations, were observed, thus making differentiation between vaccinated and infected cows possible.

2. In a survey of raw milk samples from three areas in southern Scotland, 3·5, 5·3 and 9·0% of samples were shown to be infected with Br. abortus.

Dog faeces collected from a public park were cultured on selective media for Campylobacter spp. Campylobacter jejuni was isolated from 12 (4·6%) of 260 specimens. In contrast Salmonella spp. were found in only three (1·2%). Six of the 12 isolates were nalidixic acid-resistant thermophilic campylobacters (NARTC), whereas during the same period of study none were found among human isolates. Most of the campylobacter positive faeces were found during June and July. Dog faeces deposited in public places constitute only a small potential source of infection by this organism.

A detailed analysis of equine (H3N8) influenza viruses isolated in Nigeria during early 1991 has been undertaken. Antigenic analysis and the complete nucleotide sequence of the HA gene of three Nigerian equine influenza viruses A/eq/Ibadan/4/91, A/eq/Ibadan/6/91 and A/eq/Ibadan/9/91 are presented and limited sequence analysis of each of the genes encoding the internal polypeptides of the virus has been carried out. These results establish that, despite the geographical location from which these viruses were isolated, two were similar to the viruses which were concurrently causing disease in Europe in 1989 and 1991 and were related to viruses that have been predominating in horses since 1985. The third was more closely related to viruses isolated from 1991 onward in Europe but also in other parts of the globe. A comparison of the nucleotide sequence of two of the viruses isolated in Nigeria (A/eq/Ibadan/4/91 and A/eq/Ibadan/6/91) with a European strain (A/eq/Suffolk/89) showed limited variation in the haemagglutinin gene which caused amino acid substitutions in one of the antigenic sites: this mutation resulted in the potential production of a new glycosylation site in antigenic site A. The other Nigerian virus (A/eq/Ibadan/9/91) showed only a single one amino acid change from another European strain (A/eq/Arundel/12369/91). The two distinct Nigerian viruses had several amino acid substitutions in the antigenic sites of the haemagglutinin glycoprotein.

Finally I wish to draw particular attention to the following facts:—

1. The striking diminution in the case-mortality at the Mile End Hospital which followed the systematic use of antitoxin.

2. The subsidence of the epidemic during the season when diphtheria is commonly most prevalent.

3. The opening of the schools in September without any increase in the prevalence of the disease.

4. The persistence of diphtheria bacilli for long periods in certain of the convalescents and contacts.

5. The success of preventive measures based upon the belief that diphtheria is spread mainly by personal contact, and through the inter-mediation of healthy persons and other who by the means usually employed are not recognised to be suffering from the disease.

Twenty progesterone-treated TO mice were infected intravaginally with Mycoplasma pulmonis. One month later, ten of the mice were given oestradiol which changed the reproductive cycle to the oestrous phase and within a week resulted in eradication of the organisms from six of them; vaginal persistence in the other mice may have been due, at least in part, to reinoculation of organisms from the oropharynx, a site heavily infected in all the mice. The majority of the mice not treated with oestradiol continued to shed the organisms from the vagina for at least 91 days. In another experiment, 19 oestradiol-treated BALB/c mice were infected intravaginally with M. hominis. One month later, nine of the mice were given progesterone which changed the reproductive cycle to the dioestrous phase and eradicated the organisms from seven within 2 weeks and from all of them within about a month. This was in contrast to the mice not given progesterone, the majority of which continued to shed the organisms for at least 167 days.

The post-war need for large numbers of dwellings has promoted renewed inquiry into the basic criteria by which good practice in the design and construction of buildings may be judged. More emphasis than ever before is now being put upon the functional characteristics of buildings regarded as living-spaces rather than as structures.

The investigation of 10,436 fermented tubes arising in the presumptive coliform examination of samples of water at six laboratories in England and Wales has shown that, with unchlorinated supplies, the unconfirmed presumptive test gives sufficiently accurate results. Full confirmation of all presumptive positive tubes of these waters is impracticable as a routine and ‘colony-confirmation’ gives a correction of only 0·5%. With chlorinated waters, however, ‘colony-confirmation’ discloses an error of 5·5%, largely due to the presence of anaerobes. This error can also affect the faecal coli (44° C.) count and may be so large in individual samples that assessment of chlorinated supplies should not be based on the presumptive test until this has been checked at least by plating.

Carrion is a major source of botulinal toxin for animals. A type D strain of Clostridium botulinum differed from type A and B strains in producing (1) much higher concentrations of toxin in putrefying mouse carcasses at several different temperatures over a period of 35 days, (2) toxicity that sometimes persisted in mouse carcasses for at least a year, and (3) mouse carcasses with exceptionally high oral toxicity. Fish carcasses were much less favourable than mouse carcasses for type D toxigenesis.

The study, together with earlier studies on types C and E, indicated that carrion contaminated with C. botulinum type C or D is likely to be particularly dangerous for animals that may ingest it. This accords with the observation that carrion-transmitted botulism in animals is usually caused by type C or D.

In a study comparing the responses of institutionnalized Down's syndrome (DS) and non-Down's (ND) inmates to enterovirus infections, the frequency of wild enteric viruses and the excreation patterns of oral polio vaccine (OPV) viruses were similar in both groups. Antibody titres developed to poliovirus types 2 nad 3 following vaccination were similar in DS and ND and ND vaccinees, but the responses to type I virus was signifcantly less in DS vaccinees. As judged by the development of poliovirus antibody in non-vaccinees, the spread of virus from OPV-immunized to unimmunized subjects in the institution was not noticeably different in DS and ND subjects.

An unexpected finding was that the excretion patterns of all three serotypes of poliovirus were strikingly similar for each individual to individual. The similarity of excreation occurred despite wide differences within an individual in the titres of neutralizing serum antibodies to the three serotypes. It is suggested that the rate at which a given individual eliminates enteroviruses may be largely determined by factors, the activities of which atre not reflected in serum antibody titres.

One hundred and twenty-four strains of non-penicillinase-producing gonococci isolated in Munich in 1986 were characterized in terms of their plasmid content and protein I serovar. Eighty-two per cent of the strains belonged to serogroup 1-B with over half belonging to either serovar 1B-2 or 1B-3. Half of the 22 serogroup 1A strains belonged to serovar 1A-2. Nineteen strains (15·3%) were found to lack the 2·6 Md cryptic plasmid although seven of these strains contained the 24·4 Md conjugative plasmid. Nine of the 105 strains which harboured the cryptic plasmid also contained the conjugative plasmid. The 19 strains which lacked the cryptic plasmid comprised 10 different serovars, indicating the heterogeneous nature of this group of organisms.

Contact tracing of persons with meningococcal disease who have travelled on aeroplanes or other multi-passenger transport is not consistent between countries. We searched the literature for clusters of meningococcal disease linked by transient contact on the same plane, train, bus or boat. We found reports of two clusters in children on the same school bus and one in passengers on the same plane. Cases within each of these three clusters were due to strains that were genetically indistinguishable. In the aeroplane cluster the only link between the two cases was through a single travel episode. The onset of illness (2 and 5 days after the flight) is consistent with infection from an unidentified carrier around the time of air travel. In contrast to the established risk of transmission from a case of tuberculosis, it is likely that the risk from a case of meningococcal disease to someone who is not identified as a close contact is exceedingly low. This should be considered in making international recommendations for passenger contact tracing after a case of meningococcal disease on a plane or other multi-passenger transport.