Weekly data from 7 years (2004–2010) of primary-care counts of acute respiratory illnesses (ARIs) and local weather readings were used to adjust a multivariate time-series vector error correction model with covariates (VECMX). Weather variables were included through a partial least squares index that consisted of weekly minimum temperature (coefficient = − 0·26), weekly median of relative humidity (coefficient = 0·22) and weekly accumulated rainfall (coefficient = 0·5). The VECMX long-term test reported significance for trend (0·01, P = 0·00) and weather index (1·69, P = 0·00). Short-term relationship was influenced by seasonality. The model accounted for 76% of the variability in the series (adj. R 2 = 0·76), and the co-integration diagnostics confirmed its appropriateness. The procedure is easily reproducible by researchers in all climates, can be used to identify relevant weather fluctuations affecting the incidence of ARIs, and could help clarify the influence of contact rates on the spread of these diseases.

Among pathogens shed by cattle, Escherichia coli O157 ranks highest in those causing human illness. To date, prevalence and risk factors for O157 shedding have been assessed in feedlot, but not dairy cattle. The study aimed to determine prevalence levels and risk factors for O157 atypical enteropathogenic E. coli (aEPEC) and enterohaemorrhagic E. coli (EHEC) shedding in dairy cattle. Dairy cattle (n = 899) within the first 21 days of lactation were sampled monthly over the course of 1 year, on three dry lot dairies surrounding Fort Collins, CO. During visits multiple factors were measured (disease history, pharmaceutical use, climate measures, etc.), and cattle faeces were collected and assessed for presence of O157 and virulence genes. Logistic regression analysis was performed using O157 outcomes and measured factors. Prevalence of O157 aEPEC was 3·7%, while EHEC was 3·0%. Many potential risk factors were highly correlated, and used to build separate multivariable models. An increase in humidity was positively associated with aEPEC, while fluid faeces and history of disease showed a negative association. Meanwhile, an increase in temperature and antibiotic treatment was positively associated with EHEC, while more days in milk, higher hygiene score and cow contact were negatively associated. These results may guide mitigation strategies that reduce O157 shedding, and contamination of the human food chain.

The difficulties encountered in distinguishing pneumococci from streptococci, particularly S. salivarius, have been enumerated and the morphological and cultural similarities between the two groups of organisms have been pointed out. If bile-solubility is taken as the distinguishing mark of a pneumo-coccus it will be found that there are a large number of bile-insoluble streptococci commonly met with in the respiratory tract and sometimes playing an important part in disease, which bear very strong resemblances to pneumococci both in shape, colony, and broth culture. The similarities are specially confusing in mixed cultures on agar plates and a number of the routine tests applied quite failed to distinguish them. There naturally follows the corollary that some of these tests fall wide of the mark, and they should therefore be left out of the bacteriologist's armamentarium when the identification of pneumococci is under consideration. Morphological and cultural properties are insufficient guides to species, while the same is true of the widely recommended tests of inulin fermentation and capsule formation. Not only do some pneumococci fail to ferment inulin, but so many strains of S. salivarius show active inulin fermentation that, in the present series of organisms taken at random, the incidence of inulin fermenters amongst S. salivarius is actually higher than amongst pneumococci. Capsules were found in all the strains of streptococci in which they were sought and in all the pneumococci investigated, so that encapsulation may be regarded as a property common to members of both species.

The aim of this study was to explore the frequency and distribution of gene mutations that are related to isoniazid (INH) and rifampin (RIF)-resistance in the strains of the multidrug-resistant tuberculosis (MDR-TB) Mycobacterium tuberculosis (M.tb) in Beijing, China. In this retrospective study, the genotypes of 173 MDR-TB strains were analysed by spoligotyping. The katG, inhA genes and the promoter region of inhA, in which genetic mutations confer INH resistance; and the rpoB gene, in which genetic mutations confer RIF resistance, were sequenced. The percentage of resistance-associated nucleotide alterations among the strains of different genotypes was also analysed. In total, 90.8% (157/173) of the MDR strains belonged to the Beijing genotype. Population characteristics were not significantly different among the strains of different genotypes. In total, 50.3% (87/173) strains had mutations at codon S315T of katG; 16.8% (29/173) of strains had mutations in the inhA promoter region; of them, 5.5% (15/173) had point mutations at −15 base (C→T) of the inhA promoter region. In total, 86.7% (150/173) strains had mutations at rpoB gene; of them, 40% (69/173) strains had mutations at codon S531L of rpoB. The frequency of mutations was not significantly higher in Beijing genotypic MDR strains than in non-Beijing genotypes. Beijing genotypic MDR-TB strains were spreading in Beijing and present a major challenge to TB control in this region. A high prevalence of katG Ser315Thr, inhA promoter region (−15C→T) and rpoB (S531L) mutations was observed. Molecular diagnostics based on gene mutations was a useful method for rapid detection of MDR-TB in Beijing, China.

From 1985 to 1988, a total of 2496 swine sera from 60 farms in the Tohoku District of the Honshu Island of Japan were examined for antibodies to swine haemagglutinating encephalomyelitis virus (HEV), human coronavirus (HCV) and bovine coronavirus (BCV) by haemagglutination-inhibition (HI) test. Antibodies to HEV 67N strain and HCV OC43 strain were highly prevalent with positivity rates of 82·1 and 91·4%, respectively, while seropositivity rate to BCV Kakegawa strain was 44·2%. No clinical signs of HEV infection were noticed in any farms including farms with relatively high seropositivity. The results suggested that HCV or antigenitically related virus(es) as well as HEV might be perpetuated in swine in the Tohoku District.

Small colony (SC) strains of Mycoplasma mycoides subsp. mycoides from contagious bovine pleuropneumonia (CBPP) and from goats were compared with large colony (LC) strains of so-called M. mycoides subsp. mycoides from goats and sheep by means of a cross-protection test in which mice were challenged with M. mycoides subsp. capri.

Of 13 LC strains, all gave partial cross-protection, and 11 were shown to be more closely related than four SC strains to subspecies capri. In a further experiment, six SC strains – three from CBPP and three from goats – all gave weak partial cross-protection against subspecies capri.

An indoor system designed for the study of survival of airborne micro-organisms in closed conditions has been successfully modified to allow the effect of open air to be measured. It was found that the unidentified open-air factors which are toxic for many species of microbes and rapidly lost when enclosed in conventional laboratory apparatus could be retained in the system by continuous ventilation at an adequate rate. The rate required allowed examination of Escherichia coli in aerosols generated from small amounts of material because of the short periods of ventilation required for appreciable viable decay to occur.

The validity of the system was tested by comparing the survival of E. coli in true aerosols with its survival when the droplets were held on microthread. An investigation of the role of relative humidity in open-air toxicity was included.

This study investigated whether exposure to inactivated rabbit haemorrhagic disease virus (RHDV) can produce an antigenic response in rabbits and protect them from a subsequent challenge with virulent virus. The aim was to determine if the spreading of baits containing RHDV, which is a common management practice in New Zealand to reduce rabbit numbers, could result in protective immunity in wild rabbits. RHDV was inactivated by ultraviolet (UV) light using an electronic UV crosslinker with a UV dose of 168·48 W-s/cm2 and a UV intensity of 0·0078 W/cm2. Two groups of four rabbits were then inoculated with inactivated virus via oral and intramuscular routes. Rabbits were monitored for 30 days post-inoculation and then challenged orally with virulent virus. No rabbit exposed to inactivated RHDV developed clinical signs of RHD or had antibodies at day 30 post-infection and all animals died within 82 h after challenge with virulent virus. No antibodies were detected at the time of death. These findings suggest that exposure to virus completely inactivated by UV light in the field or on baits will not protect rabbits against challenge with virulent virus.

The air of a subdivided surgical ward was sampled by the exposure of culture plates for 12 hr. periods 5 days a week.

A number of ‘broadcasts’ of airborne Staphylococcus aureus were observed; many of these were of very short duration. A single person could be recognized as responsible for 22 of the 33 broadcasts; in all cases dispersal seemed to be from carrier sites rather than from infected lesions.

There was little spread of the staphylococci between the 4 rooms of the ward. The frequency of nasal carriage of tetracycline-resistant S. aureus increased from 6·2% in patients examined during their 1st week to 13·2% in those examined in their 4th week in the ward; the rate for all S. aureus declined from 31·3 to 26·4%.

It is suggested that the long-period exposure of culture plates for the collection of airborne staphylococci may be useful in monitoring some aspects of hospital hygiene.

Mutations in the major hydrophilic region (MHR) of the surface antigen of hepatitis B virus (HBV) may result in vaccine escape, failure of immunotherapy and antiviral resistance. These mutants may be transmitted and constitute a public health threat. We aimed to determine the prevalence of MHR mutations of HBV in areas of high endemicity in Guangxi, China. HBV surface gene was analysed from 278 HBsAg-positive asymptomatic individuals recruited from Guangxi using cluster sampling. Three genotypes, B, C and I, were identified. The overall prevalence of MHR mutations is 17·6%. The prevalence of MHR mutations in genotype B (15·1%) is not significantly different from that in genotype C (16·4%). However, the prevalence in subgenotype C5 (31·1%) is significantly higher than in subgenotype C2 (13·0%) (χ2 = 6·997, P < 0·05). The prevalence of escape mutations and overlapping polymerase substitutions in subgenotype C5 is significantly higher than in subgenotypes B2 and C2. In total, 7·9% of MHR mutants are escape mutations and 72·1% of MHR mutations produced amino-acid changes in the overlapping polymerase, including resistance mutations to entecavir. Our results suggest that the prevalence of MHR mutations varies with subgenotype. The prevalence of escape mutations and polymerase mutations may be associated with subgenotype.

We aimed to assess the performance of active surveillance for hospitalized childhood encephalitis in New South Wales (NSW) using the Paediatric Active Enhanced Disease Surveillance (PAEDS) network to inform methodology for the nationwide Australian childhood encephalitis (ACE) study. We piloted active surveillance for suspected encephalitis from May to December 2013 at the Children's Hospital at Westmead, Sydney, NSW. Cases were ascertained using four screening methods: weekday nurse screening of admission records (PAEDS), cerebrospinal fluid (CSF) microscopy records, magnetic resonance imaging (MRI) reports, and pharmacy dispensing records. Comprehensive clinical data were prospectively collected on consented participants and subsequently reviewed by an expert panel. Cases were categorized as confirmed encephalitis or ‘not encephalitis’; encephalitis cases were sub-categorized as infectious, immune-mediated or unknown. We performed an ICD-10 diagnostic code audit of hospitalizations for the pilot period. We compared case ascertainment in the four screening methods and with the ICD code audit. Forty-eight cases of suspected encephalitis were identified by one or more methods. PAEDS was the most efficient mechanism (yield 34%), followed by MRI, CSF, and pharmacy audits (yield 14%, 12%, and 7% respectively). Twenty-five cases met the criteria for confirmed encephalitis. PAEDS was the most sensitive of the mechanisms for confirmed encephalitis (92%) with a positive predictive value (PPV) of 72%. The ICD audit was moderately sensitive (64%) but poorly specific (Sp 9%, PPV 14%). Of the 25 confirmed encephalitis cases, 19 (76%) were sub-categorized as infectious, three (12%) were immune-mediated, and three (12%) were ‘unknown’. We identified encephalitis cases associated with two infectious disease outbreaks (enterovirus 71, parechovirus 3). PAEDS is an efficient, sensitive and accurate surveillance mechanism for detecting cases of childhood encephalitis including those associated with emerging infectious diseases. Active surveillance significantly increases the ascertainment of encephalitis cases compared with passive approaches.

Human rabies is known to be endemic in countries bordering Lebanon, but its prevalence in Lebanon has not been studied before. All eight cases of human rabies reported to the Lebanese Ministry of Public Health between 1991 and 1999 were reviewed, as well as three other cases admitted to the American University of Beirut Medical Center. A total of 1102 cases of animal bites to humans, the majority of which were dog bites, were reported to the Ministry of Public Health between 1991 and 1996. In this period, 2487 doses of rabies vaccine were administered to the above group, as post-exposure prophylaxis. Veterinarians, a high risk and educated group, were interviewed, and only 7 out of 72 were found to have been vaccinated. Major improvements in surveillance and reporting, better control of animal rabies, more awareness especially among high risk groups, and regional cooperation, are all needed to prevent and control this deadly infection.

In most European countries the geographical distribution of simple goiter is known from the number of men who are rejected on this account for military service(1,2). There are no similar figures for Britain but what is known about its probable incidence has been discussed by Hirsch(2) and by Berry(3) and in a more recent paper, where it was also shown that there was a geographical distribution of the deaths from “exophthalmic goiter” as recorded in the Registrar General's reports(5). There were still many gaps in our knowledge, especially as regards simple goiter, but there appeared to be some tendency for deaths from “exophthalmic goiter” to be more frequent in areas where goiter was endemic, thought this was contrary to the evidence of most parts of the world where goiter was seriously endemic.

We studied the seroprevalence of hepatitis B virus (HBV), hepatitis C virus (HCV) and GB virus-C (GBV-C) infections in 348 Siberian natives who lived in the Kamchatka Peninsula of Russia. Of 348 samples studied, the seroprevalence of HBsAg and anti-HBs were 11·8% (41 of 348 samples) and 35·9% (125 of 348 samples), respectively. The prevalence of HCV infection was 1·4% (5 of 348 samples), and that of GBV-C RNA, using RT–PCR methods, was 7·5% (26 of 348 samples). In Siberia, the prevalences of HBV and GBV-C infections were about tenfold higher than those in Japan. The prevalence of HBsAg in subjects under 50 years of age was significantly higher than that in those over 50 years old (P<0·05). Because HBV infection is highly endemic in Siberia, we propose that the community-based mass immunization must be conducted as soon as possible in this area.

A total of 292 children's sera and 706 antenatal sera from different parts of England were tested for the presence of poliovirus neutralizing antibodies. Little variation was found between different areas and types of community, but a lower proportion of the 5–14 year old children had antibody than younger children and young adult women. The proportion of the young population with antibody, and the current acceptance rates for oral poliovirus vaccine are barely satisfactory.

1. An epidemic of typhoid fever involving 135 persons in a semi-closed community of. 742 persons is described.

2. There were nineteen symptomless excreters (14·1%).

3. Among the 116 clinical cases there were seven deaths, giving a case fatality of 6.03%. If the case fatality were calculated on the total persons involved (including symptomless excreters), the figure would be 5·2%.

4. The origin of the outbreak was not discovered, but there was strong cricumstantial evidence in favour of a milk-borne infection.

In his book, Floating Matter of the Air, John Tyndall (Tyndall, p. 262) quotes from Robert Boyle's ‘Essay on the Pathological Part of Physik’ ‘that he who thoroughly understands the nature of ferments and fermentations shall probably … give a fair account of divers phenomena of several diseases, which will perhaps be never properly understood without an insight into the doctrine of fermentations'. It was more than a century and a half before the first part of this suggestion was fulfilled, after which the unravelling of the causes of infective diseases proceeded rapidly. In 1836 de la Tour and, almost simultaneously, Schwann (Tyndall, p. 7) discovered, in yeast, the agent of fermentation as a living organism which reproduced itself in endless succession. Schwann also observed that putrefaction in meat broth did not set in if this was kept in contact, not with ordinary air, but with air which had been previously brought to a high temperature.

This matched case-control study investigated the risk factors for sporadic Salmonella Infantis infection in 263 affected children and 263 age-, gender- and neighbourhood-matched controls. Information about exposure to potential risk factors was obtained via telephone interview and evaluated by conditional logistic regression analysis. Age groups ⩽1 year (n = 77) and >1 year (n = 186) were analysed separately. Of those aged ⩽1 year, breastfeeding was a significant protective factor against infection [matched odds ratio (mOR) 0·24, 95% confidence interval (CI) 0·10–0·59, P < 0·01]. In the older group, consumption of eggs (mOR 1·87, 95% CI 1·00–3·49, P = 0·05) was a significant risk factor and thawing chicken in water (mOR 2·55, 95% CI 0·94–6·91, P = 0·07) was borderline risk factor, while consumption of carrots (mOR 0·46, 95% CI 0·26–0·83, P < 0·01), drinking tap water (mOR 0·44, 95% CI 0·22–0·85, P = 0·02), religious lifestyle (mOR 0·40, 95% CI 0·21–0·74, P < 0·01) and having a high number of children in the household (mOR 0·72, 95% CI 0·58–0·88, P < 0·01) were significant protective factors. Consumers should avoid eating undercooked eggs and food handlers should be educated regarding proper handling and cooking of eggs. Breastfeeding should be strongly encouraged by public health authorities. The public must be educated on stringent hygiene practices, especially proper cooking of eggs to reduce infection rates.

The clinical application of the principles of epidemiological research has become fashionable. Three recent textbooks carry the words ‘Clinical Epidemiology’ in their titles (Feinstein, 1985; Sackett, Haynes & Tugwell, 1985; Weiss, 1986), and a venerable journal has recently changed its name to this effect (Feinstein & Spitzer, 1988). Deans of medical schools, Government Health Officials and editorialists pay tribute to the new science which is expected to steer the medical profession of the third millennium.

To evaluate measles incidence and its relevant changes over a 14-year period (2000–2014), we analysed data from the regional hospital discharge database on children and adults hospitalized in Tuscany, Italy. A total of 181 paediatric and 413 adult cases were identified. Despite all the efforts towards regional measles elimination, we observed that the overall measles hospitalization rates for children and adults living in Tuscany globally increased from 0·45 to 0·85/100 000 during the study period (P = 0·001) showing fluctuations due to periodic measles outbreaks. Data stratified by age group showed that the hospitalization rate significantly increased in young adults over the study period, confirming an increase in susceptibility to measles in this subpopulation. Conversely, no statistically significant difference was observed in the hospitalization rate in the other age groups. However, children aged <1 year still exhibit the highest hospitalization rate. Pneumonia represented the most common complication in both the adult and children subsets. No death was reported. Measles still represents a public health problem, and national strategies should be implemented, focusing on emergent susceptible subsets, such as infants and young adults.