The study used DNA fingerprint typing (spoligotyping and Heminested-Inverse-PCR) of Mycobacterium tuberculosis from all culture-confirmed inner London patients over a 12-month period to describe transmission. The methodology was evaluated by comparison with standard IS6110 typing and by examining its ability to identify known household clusters of cases. Isolates sharing indistinguishable typing patterns using both techniques were defined as clustered. Clusters were investigated to identify epidemiological links. The methodology showed good discriminatory power and identified known household clusters of cases. Of 694 culture-confirmed cases, 563 (81%) were typed. Eleven (2%) were due to laboratory cross-contamination and were excluded. Of the remaining 552 isolates 148 (27%) were clustered. Multivariate analysis indicated that clustering was more common in those with pulmonary smear positive disease (P<0·02); those born in the United Kingdom (P<0·0003) and in patients living in south London (P = 0·02). There was also a trend towards clustering being more common in those not known to have HIV infection (P = 0·051). The results suggest that in inner London, recent local transmission makes an important contribution to notification rates.

In the spring term of 1985 there was a protracted outbreak of upper respiratory tract febrile illness consistent with a clinical diagnosis of influenza in a boys' boarding school, which lasted from 23 January to 29 March. Although influenza virus infection was confirmed in 89% of cases in the first half of the term, 53% of the cases which occurred in the second half of the term had no evidence of infection with influenza virus. Between 5 February and 31 March 28 boys presented with skin rashes consistent with a clinical diagnosis of erythema infectiosum; 68% of these were associated with parvovirus B19. Investigation of the cases of clinical influenza with no identified respiratory pathogen revealed a 58% infection rate with B19. B19 DNA was identified in either throat swabs or acute stage bloods of nine pupils with influenza-like symptoms.

Cohort studies revealed that 44% of pupils aged 15–16 years were immune before the outbreak compared with only 17% of pupils aged 11–12 years. Infection in the younger group was common and was associated with influenzalike illnesses as well as rashes. Forty-eight per cent of those who did not report any symptoms were also infected with B19.

A survey of rinderpest-neutralizing antibody was carried out on the sera of 315 hippopotamuses which were shot in the Queen Elizabeth Park, Uganda. No serological positives were found in animals aged 11 years or less but about 4% were detected in the age class 13–25 years. In the 28–41 years age class the proportion of positives rose to about 36%. All except one of the positive sera were titrated, the figures obtained being comparable to those in other recently infected species of wild ungulates.

It was concluded that the heat-stable antibody in hippopotamuses resulted from inapparent infections with rinderpest virus during epizootics which passed through the areas of Lake George and Lake Albert in the years 1920/21, 1931/33 and 1944/45. No record was available of clinically recognizable rinderpest in the hippopotamus population but deaths due to other causes were mentioned briefly.

Comment was made on the stability of rinderpest-neutralizing antibody over periods of about 30 years.

One of us (R. M. L) is grateful to the Nuffield Foundation for financial support. Thanks are due to Drs S. S. Stone and W. P. Heuschele (Agricultural Research Service, United States Department of Agriculture) for their assistance in organizing the collection of serum samples.

This paper is published by permission of Mr H. R. Binns, C.M.G., O.B.E., Director, E.A.V.R.O.

A survey of evidence of rodent hantavirus infection in County Down, Northern Ireland was carried out by using immunofluorescence to detect virus antigen and antibody. Antibodies to hantavirus (R22 strain of Seoul virus and Hantaan 76–118) were found in 11/51 (21·6%) brown rats (Rattus norvegicus), 1/31 (3·2%) field mice (Apodemus sylvaticus) and 17/59 (28·8%) house mice (Mus domesticus). Seven rodents had evidence of hantavirus antigen in lung tissues. Antibody positive animals were significantly more likely to be adults than juveniles (P = 0·04) but and there was no sex difference between antibody positive and negative animals. House mice were more likely to be antibody positive if captured inside farm outbuildings (P = 0·08). Attempts to culture virus from the rodent material were unsuccessful. This work demonstrates a substantial rodent reservoir for hantavirus in Northern Ireland.

Factors affecting the formation and destruction of sulphide in the Thames Estuary have been discussed. Measurements of oxidation-reduction potentials show that the effect of oxygen in the water on conditions in deposits of mud is limited to the surface layer. The rate of formation of sulphide increases with temperature, doubling approximately for each 10° C. rise. Reduction of sulphate to sulphide will occur at temperatures as low as 5° C., but even at 25° C. is inhibited by traces of dissolved oxygen. Mud in suspension in the estuary can produce as much sulphide as compact layers of similar mud which might be more anaerobic.

Oxidation of sulphide in the Thames Estuary is shown to be of a purely chemical nature; the rate of oxidation, when oxygen is present, is increased by the presence of suspended matter and iron. In the Thames Estuary, however, the rate is limited by the rate at which oxygen enters the water.

Much of the experimental work described in this paper was carried out by Miss A. Laird, Mr A. E. Sutton and Mr R. B. Peel of this Laboratory. The paper is published by permission of the Department of Scientific and Industrial Research.

The important role of plasmid genes in assessing virulence for BALB/c mice in salmonella, and the difficulty of using standard techniques to detect them, led us to develop a detection method by gene amplification.

One hundred and forty–three strains (71 serovars) of salmonella and 35 strains of other species were tested using specific oligonucleotide primers. The amplification products were identified by a specific oligonucleotide probe. Forty-nine salmonella strains from ten serovars (S. abortus ovis, S. choleraesuis, S. dublin, S. enteritidis, S. gallinarum / pullorum, S. hessarek, S. typhimurium, S. IIIa 48:z4, z23, S. IV 43: z4, z23:-, S. V 28:a:-) produced a positive and specific response.

Because of various origins of the strains possessing the gene sought and the diversity of the responses, both from one serovar to another and in the same serovar, this search has its place among the epidemiological markers in general use. This method appears well suited to the research and detection of plasmid genes associated with mouse virulence in salmonella.

It is concluded from a study of the morphological and cultural characters of 60 strains of Döderlein's vaginal bacillus that the organism belongs to the lacto-bacillus group of bacteria.

Primary culture of Döderlein's bacillus may be readily obtained on lactose blood agar incubated aerobically provided the vaginal flora is of “Grade A” type, but its subsequent propagation on artificial culture media is less likely to be successful.

Three morphological types of Döderlein's bacillus are recognised. Cultural and fermentative tests show that these types are all biologically similar.

There is no serological homogeneity among the strains of Döderlein's bacillus, although there was some evidence of a serological relationship among the members of the commonest morphological type. The same serological type tends to persist in the vagina throughout pregnancy. Döderlein's bacillus and lacto-bacilli derived from other sources are not serologically identical.

Antiretroviral therapy (ART) is increasingly being used as an HIV-prevention tool, administered to uninfected people with ongoing HIV exposure as pre-exposure prophylaxis (PrEP) and to infected people to reduce their infectiousness. We used a modelling approach to determine the optimal population-level combination of ART and PrEP allocations required in South Africa to maximize programme effectiveness for four outcome measures: new infections, infection-years, death and cost. We considered two different strategies for allocating treatment, one that selectively allocates drugs to sex workers and one that does not. We found that for low treatment availability, prevention through PrEP to the general population or PrEP and ART to sex workers is key to maximizing effectiveness, while for higher drug availability, ART to the general population is optimal. At South Africa's current level of treatment availability, using prevention is most effective at reducing new infections, infection-years, and cost, while using the treatment as ART to the general population best reduces deaths. At treatment levels that meet the UNAIDS's ambitious new 90–90–90 target, using all or almost all treatment as ART to the general population best reduces all four outcome measures considered.

The purpose of this study was to investigate carriage of intestinal spirochaetes by selected population groups in Western Australia. Stool specimens from 293 rural patients with gastrointestinal disorders, and from 227 healthy migrants from developing countries were cultured. Spirochaete isolates were identified using PCR, and typed by pulsed field gel electrophoresis (PFGE). Brachyspira aalborgi was not isolated. Brachyspira pilosicoli was recovered from 15 rural patients, all Aboriginal. Prevalence was 9·9% in 151 Aboriginals and 0% in 142 non-Aboriginals. Carriage of B. pilosicoli amongst migrants was 10·6% (24/227). Carriage was significantly increased in Aboriginal children aged 2–5 years (P = 0·0027) and in migrant individuals from the Middle East and Africa (P = 0·0034). Carriage was significantly associated with detection of faecal protozoa in both Aboriginals (P = 0·0021) and migrants (P = 0·012). PFGE results indicated that the B. pilosicoli strains were genetically diverse.

Although Middle East respiratory syndrome coronavirus (MERS-CoV) has a recorded 5 years of circulation in 27 countries worldwide, there is no international study to assess whether there is variation in mortality by region. Neither has there been a comprehensive study detailing how the disease characteristics of MERS-CoV influence mortality in patients presenting symptoms. This study aimed to assess how region, patient and disease characteristics influence 14- and 45-day mortality in MERS patients. The author utilised publically available data on MERS-CoV. The study included 883 MERS patients reported between 5 January 2015 and 10 March 2017. Data on patient and disease characteristics were collected. The mean age at MERS-CoV diagnosis was 54.3 years: 69.1% were male, and 86.7% of the cases were reported from Saudi Arabia. About 40% of MERS patients studied were over the age of 60. The study estimated 14- and 45-day survival rates after initial onset of symptoms: 83.67% and 65.9%, respectively. Saudi Arabian MERS patients exhibited 4.1 and 5.0 times higher 14-day (adjusted hazard risk (aHR) = 4.1; 95% confidence interval (CI) 1.012–16.921) and 45-day (aHR = 5.0; 95% CI 1.856–13.581) mortality risk compared with MERS patients in the Republic of Korea or other countries. Similarly, Middle Eastern MERS patients showed 5.3 and 4.1 times higher 14-day (aHR = 5.3; 95% CI 1.070–25.902) and 45-day (aHR = 4.1; 95% CI 1.288–113.076) mortality risk compared with MERS patients in the Republic of Korea or other countries. The results demonstrated a link between mortality and geography, disease and patient factors such as regions, symptoms, source of infections, underlying medical conditions, modes of transmission, non-healthcare workers and those of older age. Educational programmes, access to healthcare and early diagnosis could be implemented as modifiable factors to reduce the higher mortality rates in MERS patients.

The 13-valent pneumococcal conjugate vaccine (PCV) has been part of routine immunisation in a 2 + 1 schedule (two primary infant doses and one booster during the second year of life) in the UK since 2010. Recently, the UK's Joint Committee on Vaccination and Immunisation recommended changing to a 1 + 1 schedule while conceding that this will increase disease burden; however, uncertainty remains on how much pneumococcal burden – including invasive pneumococcal disease (IPD) and non-invasive disease – will increase. We built a dynamic transmission model to investigate this question. The model predicted that a 1 + 1 schedule would incur 8777–27 807 additional cases of disease and 241–743 more deaths over 5 years. Serotype 19A caused 55–71% of incremental IPD cases. Scenario analyses showed that booster dose adherence, effectiveness against carriage and waning in a 1 + 1 schedule had the most influence on resurgence of disease. Based on the model assumptions, switching to a 1 + 1 schedule will substantially increase disease burden. The results likely are conservative since they are based on relatively low vaccine-type pneumococcal transmission, a paradigm that has been called into question by data demonstrating an increase of IPD due to several vaccine serotypes during the last surveillance year available.

1. Two preparations of bacteriophage were used for the treatment of a number of cases of acute bacillary dysentery.

2. The types of B. dysenteriae encountered in 60 cases of acute bacillary dysentery are described. In the 60 cases investigated the causal bacillus was bacteriophagable with the standard bacteriophage in vitro in 48.

3. The cases are tabulated and no dramatic results due to the bacteriophage treatment are demonstrated.

4. Treatment of the bacteriophage with hydrochloric acid, in a concentration similar to that of the gastric juice, for 60 minutes did not alter the virulence of the bacteriophage.

5. It is shown that 25 per cent, autoclaved intestinal mucus in normal saline, and human blood serum, not inactivated, compare unfavourably with laboratory broth as a medium for bacteriophage action.

6. The results of giving bacteriophage by mouth to normal individuals, and to dysentery patients are described and discussed.

Salmonella enterica serovar Infantis is endemic in Finnish cattle. Feed contaminated with S. Infantis was distributed to cattle farms in May 1995. Following increased sampling, S. Infantis was detected on 242 farms in 1995. Molecular typing was used to differentiate the farms that were infected by the feed-related Infantis from those infected by other endemic strains. Twenty-three isolates from feed in 1995 and 413 from cattle (72 from 1992–4, 324 from 1995, 17 from 1996–7) were analysed. The feed-related Infantis was clonally related to the endemic infection by the ribotype, IS200-type and XbaI-profile. The feed isolates had a distinctive plasmid that appeared in pulsed-field gel electrophoresis as a 60 kb band when cleaved with XbaI or linearized by S1-nuclease. This plasmid appeared in cattle only since the outbreak and seemed stable on the follow-up farms. In addition to contact farms, the feedborne strain was found on 19% of the farms infected with S. Infantis in 1995 but not having bought suspected feedstuffs, possibly as secondary infections.

The depopulation of Pacific islands during the 16th to 19th centuries is a striking example of historical mass mortality due to infectious disease. Pacific Island populations have not been subject to such cataclysmic infectious disease mortality since. Here we explore the processes which could have given rise to this shift in infectious disease mortality patterns. We show, using mathematical models, that the population dynamics exhibited by Pacific Island populations are unlikely to be the result of Darwinian evolution. We propose that extreme mortality during first-contact epidemics is a function of epidemiological isolation, not a lack of previous selection. If, as pathogens become established in populations, extreme mortality is rapidly suppressed by herd immunity, Pacific Island population mortality patterns can be explained with no need to invoke genetic change. We discuss the mechanisms by which this could occur, including (i) a link between the proportion of the population transmitting infectious agents and case-fatality rates, and (ii) the course of infection with pathogens such as measles and smallpox being more severe in adults than in children. Overall, we consider the present-day risk of mass mortality from newly emerging infectious diseases is unlikely to be greater on Pacific islands than in other geographical areas.

Tuberculosis (TB) is the leading cause of death among infectious diseases worldwide. Among the estimated cases of drug-resistant TB, approximately 60% occur in the BRICS countries (Brazil, Russia, India, China and South Africa). Among Brazilian states, primary and acquired multidrug-resistant TB (MDR-TB) rates were the highest in Rio Grande do Sul (RS). This study aimed to perform molecular characterisation of MDR-TB in the State of RS, a high-burden Brazilian state. We performed molecular characterisation of MDR-TB cases in RS, defined by drug susceptibility testing, using 131 Mycobacterium tuberculosis (M.tb) DNA samples from the Central Laboratory. We carried out MIRU-VNTR 24loci, spoligotyping, sequencing of the katG, inhA and rpoB genes and RDRio sublineage identification. The most frequent families found were LAM (65.6%) and Haarlem (22.1%). RDRio deletion was observed in 42 (32%) of the M.tb isolates. Among MDR-TB cases, eight (6.1%) did not present mutations in the studied genes. In 116 (88.5%) M.tb isolates, we found mutations associated with rifampicin (RIF) resistance in rpoB gene, and in 112 isolates (85.5%), we observed mutations related to isoniazid resistance in katG and inhA genes. An insertion of 12 nucleotides (CCAGAACAACCC) at the 516 codon in the rpoB gene, possibly responsible for a decreased interaction of RIF and RNA polymerase, was found in 19/131 of the isolates, belonging mostly to LAM and Haarlem families. These results enable a better understanding of the dynamics of transmission and evolution of MDR-TB in the region.

A review of the epidemiology of clinical rubella in the Perm region of the Russian Federation from 1979–97 showed that the incidence was about 220 cases per 100000 population. Congenital rubella syndrome (CRS) accounted for 15% of birth defects and for about 3·5 cases of CRS per 1000 live births per year. Surveys of the seroepidemiology of rubella infection revealed that the susceptibility rate among pregnant women (i.e. rubella virus antibody haemagglutination-inhibition (HAI) assay titres < 10) was 16·5%. As serum rubella antibody HAI titres [ges ] 10 both prevented infection in pregnant women and protected their foetuses, serological testing has been introduced into the routine antenatal services. Pre-existing rubella antibodies were found not to interfere with the immune response to vaccination, so selective immunization was provided to girls approaching puberty and to women of childbearing age. A programme of epidemiological surveillance is being developed to define tactics for the widescale introduction of rubella vaccination.

Incidence of various diseases can increase following a flood. We aimed to identify professionals in Copenhagen who became ill after contact with 2 July 2011 floodwater/sediment and determine risks and protective factors associated with illness. We conducted a cohort study of employees engaged in post-flood management activities. Participants completed a questionnaire collecting information about demographics, floodwater/sediment exposure, compliance with standard precautions, and symptoms of illness. Overall, 257 professionals participated, with 56 (22%) cases. Risk of illness was associated with not washing hands after floodwater/sediment contact [relative risk (RR) 2·45], exposure to floodwater at work and home (RR 2·35), smoking (RR 1·92), direct contact with floodwater (RR 1·86), and eating/drinking when in contact with floodwater (RR 1·77). Professionals need to follow standard precautions when in contact with floodwater/sediment, especially proper hand hygiene after personal protective equipment use and before eating/drinking and smoking.

Pneumonia in well known to be extremely fatal at both extremes of life. In 1923 it was the cause of 3671 deaths per million living at ages under 5 years; between ages 5–24 the death-rate fell to 177 and rose to 376 at ages 25–44. after 45 the increase was rapid and the death-ate reached 2279 per million living for the ago group 65–74 and 4100 for all ages over 75 years.

Methods for measuring the temperature and humidity of the air beneath the shirt are described.

Conditions of temperature and humidity under the shirt are described, for a resting person, with external temperatures varying between 0° C. and 41° C., under different atmospheric humidities. The air beneath the shirt varied between 23° C. and 37° C., and 23 and 70 per cent. relative humidity. The saturation deficiency of the air beneath the shirt varied very little—only between 13 and 18 mm.—in all the observations taken.

I am indebted to Dr P. A. Buxton for many helpful suggestions and for reading the manuscript. Also to Prof. G. H. F. Nuttall, F.R.S., for drawing my attention to literature on the earlier work.

Leptospirosis is an important public health problem in the Andaman Islands. The disease is being increasingly reported among children and adolescents in recent times. An attempt was made to find out the level of exposure to leptospires, to estimate the incidence of infection and to identity the risk factors for acquiring infection among children. A sample of 1544 schoolchildren was selected. Presence of anti-leptospiral antibodies was tested using the microscopic agglutination test (MAT). Students were interviewed for behavioural factors. In total, 341 (221 seronegative and 120 seropositive) students were followed up clinically and serologically during a subsequent outbreak. An overall seropositivity rate of 23·6% (95% CI 21·54–25·81) was observed. Infection rate was 33·5% among seronegatives whereas re-infection rate was 16·7% among seropositives during the outbreak that occurred 1 month after the first sample collection. Morbidity and mortality were found to be higher among seronegative individuals than serpositives, More than 90% of leptospiral infections were found to be subclinical or unnoticed. The high level of exposure among the children results in high infection rates and because they have less previous exposure than adults, they do not have sufficient protection to resist clinical illness during outbreaks.