The aim of this study was to apply a back-calculation model to Great Britain (GB) classical scrapie surveillance data, and use this model to estimate how many more cases might be expected, and over what time frame these cases might occur. A back-calculation model was applied to scrapie surveillance data between 2005 and 2019 to estimate the annual rate of decline of classical scrapie. This rate was then extrapolated to predict the number of future cases each year going forward. The model shows that there may be yet further cases of classical scrapie in GB. These will most likely occur in the fallen stock scheme, with approximately a 25% probability of at least 1 further scrapie positive, with a very low probability (~0.2%) of having up to three additional scrapie positives. This highlights the difficulty of completely eliminating all further cases, even in the presence of very effective control measures.

Varicella infection during pregnancy has serious and/or difficult implications and in some cases lethal outcome. Though epidemiological studies in developing countries reveal that a significant proportion of patients may remain susceptible during pregnancy, such an estimate of susceptible women is not known in India. We designed this study to study the prevalence and factors associated with susceptibility to varicella among rural and urban pregnant women in South India. We prospectively recruited 430 pregnant women and analysed their serum varicella IgG antibodies as surrogates for protection. We estimated seroprevalence, the validity of self-reported history of chickenpox and factors associated with varicella susceptibility. We found 23 (95% CI 19.1–27.3) of women were susceptible. Nearly a quarter (22.2%) of the susceptible women had a history of exposure to chickenpox anytime in the past or during the current pregnancy. Self-reported history of varicella had a positive predictive value of 82.4%. Negative history of chickenpox (adjusted prevalence ratio (PR) 1.85, 95% CI 1.15–3.0) and receiving antenatal care from a rural secondary hospital (adjusted PR 4.08, 95% CI 2.1–7.65) were significantly associated with susceptibility. We conclude that high varicella susceptibility rates during pregnancy were noted and self-reported history of varicella may not be a reliable surrogate for protection.

Although Africa is home to about 14% of the global population (1.14 billion people), it is growing three times faster than the global average [1]. The continent carries a high burden of disease, but there has been real progress in eradication, elimination, and control since 2015. Examples are the eradication of wild polio in 2020 [2] and the eradication or elimination of neglected tropical diseases, such as dracunculiasis in Kenya in 2018; Human African trypanosomiasis in Togo in 2022; and trachoma in Togo, Gambia, Ghana, and Malawi in 2022 [3]. New HIV infections reduced by 44% in 2021 compared to 2010 [4], and in 2021 the African region passed the 2020 milestone of the End TB Strategy, with a 22% reduction in new infections compared with 2015 [5].

Campylobacter spp. are one of the most common causes of bacterial gastroenteritis in Canada and worldwide. Fluoroquinolones are often used to treat complicated human campylobacteriosis and strains of Campylobacter spp. resistant to these drugs are emerging along the food chain. A scoping review was conducted to summarise how human (fluoro)quinolone-resistant (FQR; quinolones including fluoroquinolones) Campylobacter spp. infections are characterised in the literature by describing how burden of illness (BOI) associated with FQR is measured and reported, describing the variability in reporting of study characteristics, and providing a narrative review of literature that compare BOI measures of FQR Campylobacter spp. infections to those with susceptible infections. The review identified 26 studies that yielded many case reports, a lack of recent literature and a lack of Canadian data. Studies reported 26 different BOI measures and the most common were hospitalisation, diarrhoea, fever and duration of illness. There were mixed results as BOI measures reported in literature were inconsistently defined and there were limited comparisons between resistant and susceptible infections. This presents a challenge when attempting to assess the magnitude of the BOI due to FQR Campylobacter spp., highlighting the need for more research in this area.

The Houston Health Department (HHD) in Texas tracks influenza-like illness (ILI) in the community through its Influenza Sentinel Surveillance Program, which began in 2008. After the influenza A(H1N1) pandemic (pH1N1) in 2009, investigators sought to assess the feasibility of this program as a non-traditional data source for tracking and monitoring care-seeking activities. Through the process of characterizing and describing patients who had ‘return visits’, or who were considered the heaviest ILI-related care-utilizers, the investigators sought to understand the strengths and limitations of this data source. Data used for this study were obtained from a multispecialty clinic in Houston, Texas between August 2008 and January 2011 across three phases: pre-pH1N1, pH1N1, and post-pH1N1. The data, which comprised of 4047 patient visits, yielded 150 return visits. We found an increase in the number of visits for ILI and proportion of return visits during the pandemic phase (pH1N1), as well as differences in the likelihood of a return visit between genders and age groups. More broadly, the findings of this study provide important considerations for future research and expose important gaps in using surveillance data to assess sick-role behaviors.

We determined prescribing rates of neuraminidase inhibitors (NIs) for influenza in UK primary care since 2009 in relation to national prescribing guidelines. All NI prescriptions issued during the influenza seasons between October 2010 and May 2013 were extracted from The Health Improvement Network (THIN), a large UK primary-care database. We calculated NI prescribing rates per 100 000 person-weeks (pw) by age group, sex, deprivation level, influenza season and presence of chronic conditions with 95% confidence intervals (CIs), and used negative binomial regression models to determine the independent association between these variables and NI prescribing. NI prescribing was rare. The prescribing rate was 1·7/100 000 pw (95% CI 1·7–1·8) during influenza-active periods, and 0·1/100 000 (95% CI 0·1–0·1) during non-active periods. Prescribing rates were highest in 25- to 44-year-olds in 2010/2011 and in persons aged ⩾85 years in 2011/2012 and 2012/2013. Individuals with chronic conditions had significantly higher prescribing rates than persons without (rate ratio 2·62, 95% CI 2·27–3·03). GPs are more likely to prescribe NIs to high-risk individuals and during influenza active periods, as per national guidelines. We could not assess the proportion of patients with influenza-like illness who were prescribed an NI.

In this multicentre study, we compared the status of antibody production in healthcare personnel (HCP) before and after vaccination using different brands of COVID-19 vaccines between March 2021 and September 2021. Out of a total of 962 HCP enrolled in our study, the antibody against the S1 domain of SARS-CoV-2 was detected in 48.3%, 95.5% and 96.2% of them before, after the first and the second doses of the vaccines, respectively. Our results showed post-vaccination infection in 3.7% and 5.9% of the individuals after the first and second doses of vaccines, respectively. The infection was significantly lower in HCP who presented higher antibody titres before the vaccination. Although types of vaccines did not show a significant difference in the infection rate, a lower infection rate was recorded for AstraZeneca after the second vaccination course. This rate was equal among individuals receiving a second dose of Sinopharm and Sputnik. Vaccine-related side effects were more frequent among AstraZeneca recipients after the first dose and among Sputnik recipients after the second dose. In conclusion, our results showed diversity among different brands of COVID-19 vaccines; however, it seems that two doses of the vaccines could induce an antibody response in most of HCP. The induced immunity could persist for 3–5 months after the second vaccination course.

1. Preparations for petrographical examination were obtained by micro-incineration of sections from silicotic nodules from thirty-one cases of unequivocal silicosis.

2. Particle counts above and below 2 μ showed, in the majority of cases, a preponderance of quartz.

3. Jones' claim that sericite particles predominate in the lower size range of particles in silicotic lungs is not confirmed.

Sera from 252 patients with community-acquired pneumonia were examined for the presence of antibodies to 15 antigens of 7 Legionella spp. by indirect immunofluorescent antibody testing. The sera had been collected as part of the British Thoracic Society/Public Health Laboratory Service study of community-acquired pneumonia in adults. We also examined sera from 20 patients with gram-negative sepsis.

Two temperature-sensitive mutants of the Ukg 27/72 strain of swine vesicular disease virus were isolated in tissue culture and a third was derived following adaptation in mice. All three were found to have similar growth restrictive temperatures, but varied considerably in their virulence when administered to pigs. The route of inoculation appeared to exert a considerable influence on the apparent degree of attenuation, the antibody titre engendered and the transmission of disease to pigs held in contact with inoculated animals. One strain appeared almost totally attenuated when inoculated into pigs but spread to animals in contact causing severe disease. Virus re-isolated from one such animal was found to have retained its temperature sensitive phenotype, suggesting that virulence in this case was not directly related to temperature sensitivity. Pigs with high antibody titres were found to be susceptible when placed in contact with challenge animals, although the lesions which developed were mild.

The blood culture records during the 6-year period 1984–9 were reviewed to compare the performance of the BACTEC aerobic (6B) and aerobic-hypertonic (8B) media for the recovery of Candida spp. and Torulopsis glabrata from blood. There were 137 positive blood culture sets that contained both a 6B and an 8B bottle. Sixty-eight different yeasts were recovered from 65 patients including 35 Candida albicans, 19 C. tropicalis, 6 C. parapsilosis, 4 C. krusei, 1 C. pseudotropicalis and 3 Torulopsis glabrata. The 8B medium detected 120 of the positive cultures (87·6%) and was the only positive medium in 35 (25·6%) sets, while the 6B medium detected 102 positive cultures (74·4%) and was the only positive medium in 17 (12·4%) sets (P < 0·04). For those sets in which both bottles were positive, radiometric detection occurred first in the 8B bottle in 39 sets and first in the 6B bottle in 11 sets (P < 0·001). The superior performance of the 8B bottle was not related to the administration of amphotericin B. Cultures of stock strains of C. albicans, C. tropicalis, and C. parapsilosis in 6B and 8B media with and without added blood confirmed the finding that 8B was substantially superior to 6B for the detection of candidaemia. It is concluded that an 8B bottle should be included in the blood culture set whenever candidaemia is suspected.

Two hundred and sixty strains of Pseudomonas aeruginosa were isolated from patients of the Asaf Harofe Government Hospital. The strains were typed by phage technique and 64 of them were also typed according to pyocine sensitivity. The two methods proved complementary, and reduced the number of untypable strains. Phage typing was performed with both routine test dilution (RTD) and more concentrated phage suspensions. The most reliable results were obtained at 100 RTD.

1. The typhoid bacillus can survive in natural soil in large numbers for about 20 days and is still present in a living condition after 70 to 80 days.

2. There is no evidence that the typhoid bacillus is capable of multiplying and leading a saprophytic existence in ordinary soil.

3. In some samples of soil, but not in all, the typhoid bacillus dies out much more rapidly (in 11 days) if the soil has previously been subjected to sterilisation by steam under pressure. This is apparently due to the production of bactericidal substances during sterilisation.

Bacteriological tests alone are not capable of predicting the keeping quality of cream, since taints can develop which are due to non-bacterial action. When spoilage is due to bacterial growth, the water agar test was found to be more accurate than the other tests that were examined.

A total of 849 samples of pig sera were tested for antibodies to L. canicola, L. icterohaemorrhagiae, L. pomona, L. ballum, L. sejroe, L. grippotyphosa, L. hyos (mitis Johnson), and L. bataviae. Positive results were obtained in 57 samples to all but the last three serotypes.

I wish to thank Mr J. Norval of Edinburgh and Mr W. R. P. Hildebrand of Belfast for supplying the sera and Dr A. Wilson Taylor for his interest and supervision.

I am greatly indebted to the late Dr J. C. Broom of the Wellcome Laboratories of Tropical Medicine for the supply of leptospira.

The morphological, cultural, biochemical, serological and pathogenic properties of two bacterial strains of the group designated ‘Br. suis biotype 5’ were examined. Both strains were found to be atypical of the genus Brucella in many of these characteristics. No serological relationship to known brucella strains could be detected. On the basis of the evidence obtained the two strains examined were classified as Moraxella duplex and the status of ‘Br. suis biotype 5’ questioned.

Lungs exposed to occupational dust may be especially vulnerable to fatal infections. We followed up asbestos-exposed workers (n=590) originally screened for lung cancer with computed tomography and scored for pleuropulmonary fibrosis. We checked these workers' influenza and pneumonia mortality data (ICD-10 codes J10–J18) in the national register. In total, 191 deaths, including 43 deaths from infectious pneumonia, occurred in 6158 person-years of follow-up (mean follow-up time 10·44 years). ‘Some interstitial fibrosis’ [hazard ratio (HR) 2·26, 95% confidence interval (CI) 0·98–5·19, P=0·06] and ‘definite interstitial fibrosis’ (HR 3·70, 95% CI 1·22–11·23, P=0·02) were associated with an increased risk of death from pneumonia compared to no fibrosis. Asbestosis patients, i.e. those with both asbestos exposure and lung fibrosis, therefore appear to be particularly at risk for death from pneumonia. These patients should be vaccinated against influenza and Pneumococcus.

The subject-matter of this paper is a study of the relationship which exists between the natural immunity enjoyed by an individual to any disease, and the capacity which he possesses of acquiring immunity if attacked. Most of the facts discussed are moderately well known. They are furnished by the statistics of the acute infectious diseases which have accumulated since the middle of last century. These statistics are in many respects very defective for the purpose required, but they refer to very considerable numbers of cases, and thus afford a basis for the estimation of different degrees of immunity with some accuracy. The most numerous collection of statistics relates to small-pox among the vaccinated and unvaccinated. These have been dealt with in an earlier paper1, and the results alone will be referred to here. This group of statistics unfortunately practically exhausts the whole data concerning acquired immunity. The next statistics of importance are those referring to the different outbreaks of typhus, relapsing, and enteric fever, and of a few other less common diseases. Last must be placed those regarding the diseases which chiefly affect children. These for several reasons, however, afford less definite data.

There are few studies from developing countries on the epidemiology of Haemophilus influenzae (Hib) infections among infants and children. We set out to determine the prevalence of oropharyngeal Hib colonization among Turkish children younger than two years of age and to identify antimicrobial resistance among the isolates. A cross-sectional study was conducted on 818 healthy children and oropharyngeal secretions were sampled. The carriage rate of Hib was found to be 7·2% and this increased significantly with age. Carriage of Hib among 3- to 6-month-old children (3·5%) was higher than expected and was significantly higher among children who were passive smokers (P=0·04). Logistic regression analysis showed that breastfeeding status was the sole significant factor for colonization (OR 2·2, 95% CI 1·26–3·82). Antimicrobial susceptibility tests on 56 isolates of H. influenzae showed that 51·8% and 21·4% were resistant to trimethoprim–sulphamethoxazole and ampicillin respectively. Other notable resistances were to cefalexin (10·7%) and chloramphenicol (3·6%); no isolates were resistant to ceftriaxone.

1. The effects of morphine, diacetylmorphine (heroin), methylmorphine (codeine), dihydromorphinone (dilaudid), dihydrocodeinone (dicodid) and dihydroxycodeinone (eukadol) upon the rectum are described.

2. Morphine hydrochloride produces an immediate well-marked increase in rectal tone, which returns to normal about ½ hr. later. Waves of increased tone followed by relaxation are seen during the next 3–4 hr., each wave lasting approximately ½ hr. At the 5 or 6 hr. stage the tone is generally subnormal and remains so for many hours afterwards. The amplitude of the rectal movements is slowly increased, reaching a maximum about 3 hr. later, when they are usually very large and much slower than normal. Later the movements decline to a subnormal amplitude. These effects are abolished by the administration of atropine, and subsequent injections of morphine hydrochloride given within a few hours fail to reproduce them.

3. The effects of diacetylmorphine hydrochloride (heroin) are similar to those of morphine hydrochloride, except that it rarely leaves the rectum in a subnormal state of tone at any time during the first 8 hr. following the injection of the drug. In two experiments a slight relaxation beyond the normal limits was observed at the 5 hr. stage, but it was so small as to be negligible.

4. Methylmorphine phosphate (codeine) produces effects upon the tone and movements which resemble those of morphine, but they are always less marked in degree and of shorter duration than those of morphine. With codeine the effects never lasted longer than 30–45 min.; secondary waves of increased tone, such as were seen after the administration of morphine, diacetylmorphine, dicodid or eukadol, were never observed following the use of codeine. The tone level of the rectum was never subnormal at the 5 hr. stage or later. The effects of codeine were always immediately abolished by atropine, after which codeine was ineffective.

5. Diacetylmorphinone hydrochloride (dilaudid) is a very potent drug, producing very marked effects upon the rectum even when very small doses were employed. Small amounts of the drug cause an immediate increase in tone without any change in the character or rate of the movements. Normal tone was re-established 30–45 min. later, when it declines still further to a subnormal level, reaching its lowest level at 70–90 min. Larger doses of dilaudid produced an increase in the amplitude of the movements in addition to increasing the tone. These effects lasted approximately 30 min., when both tone and movements were normal again. The tone level was generally markedly subnormal at the 6–8 hr. stage. The effects of dilaudid were immediately abolished by atropine, after which dilaudid was ineffective.

6. Dihydrocodeinone hydrochloride (dicodid) is a very active drug which produces an increase in the activity of the rectum which is far greater than that produced by morphine, heroin, codeine, or dilaudid. The immediate effect of dicodid is an increase in rectal tone, accompanied by some decrease in the amplitude of the movements. Later the tone decreases far in excess of normal. Secondary waves of increased tone, each one of 15–25 min. duration, were observed to recur during the first 4½ hr. following the administration of the drug. The tone level of the rectum was never subnormal, even at the 8 hr. stage. The effects of dicodid were always inhibited after the administration of atropine, while the subsequent injection of dicodid always produced its usual effects, which were, however, modified and of shorter duration.

7. Dihydroxycodeinone hydrochloride (eukadol) at first increases the tone of the rectum to a marked extent and later the amplitude of the movements. Secondary waves of increased tone, each one of 18–25 min. duration, and separated from the next by an interval of 8–15 min., were observed through the first 2½–3 hr. following the administration of the drug. The effect of eukadol upon the rectal movements is extremely marked. The maximum-increase in their amplitude was generally observed at the 3–3½ hr. stage, when the tone was subnormal. At the 8 hr. stage the tone was always subnormal, while the movements were decreasing in both rate and amplitude. Atropine immediately inhibited the action of eukadol upon the rectum, while the subsequent administration of eukadol always produced a marked increase in tone without much change in the amplitude of movements.

8. Codeine phosphate is undoubtedly the weakest member of this series in so far as the effects produced upon the rectum are concerned, while dihydrocodeinone (dicodid) and dihydroxycodeinone (eukadol) are the most active.