This study was conducted to determine the molecular epidemiology of methicillin-resistant Staphylococcus aureus (MRSA) in Malaysian hospitals. A total of 264 MRSA isolates from eight hospitals were subjected to typing by pulsed-field gel electrophoresis (PFGE) of SmaI restricted DNA. Antibiotic disk susceptibility testing was also carried out to determine their resistance patterns. Thirty-one PFGE pattern types were identified. Three major pattern types A, ZC and K were found with type A the predominant profile in c. 80% of strains and present in all hospitals. Unlike type A, other DNA pattern types were unique to the hospitals in which they were isolated. PFGE type A also consisted of strains that were multiply antibiotic resistant. The presence of a single predominant PFGE type in Malaysian hospitals is an important finding which suggests that inter-hospital spread of MRSA had occurred frequently and regularly.

One of us (S. L. C.), with C. Weatherall and E. T. Waters, published in 1931 the results of some experiments on the adsorption of the active principle of tuberculin by the dust of anthracite coal and showed that the activity of a diluted tuberculin was greatly diminished after contact with pulverized anthracite. In view of this fact, we made the suggestion that some such adsorbent action of autotuberculin by the finely divided coal-dust retained in the lung tissues of silico-anthracotic coal-miners might, perhaps, explain the relative freedom of these latter from the progressive pulmonary tuberculosis so commonly noted as a sequel to silicosis in gold-miners and others exposed to silicious dust free from admixture with coal-dust. These experiments have since been repeated by us with similar results and we, therefore, planned to try out the adsorption effects of other dusts liable to be inhaled in the course of coal-mining in South Wales.

Newcastle disease (ND) is a notifiable disease affecting chickens and other avian species caused by virulent strains of Avian paramyxovirus type 1 (APMV-1). While outbreaks of ND can have devastating consequences, avirulent strains of APMV-1 generally cause subclinical infections or mild disease. However, viruses can cause different levels of disease in different species and virulence can evolve following cross-species transmission events. This report describes the detection of three cases of avirulent APMV-1 infection in Great Britain (GB). Case 1 emerged from the ‘testing to exclude’ scheme in chickens in Shropshire while cases 2 and 3 were made directly from notifiable avian disease investigations in chicken broilers in Herefordshire and on premises in Wiltshire containing ducks and mixed species, respectively). Class II/genotype I.1.1 APMV-1 from case 1 shared 99.94% identity to the Queensland V4 strain of APMV-1. Class II/genotype II APMV-1 was detected from case 2 while the class II/genotype I.2 virus from case 3 aligned closely with strains isolated from Anseriformes. Exclusion of ND through rapid detection of avirulent APMV-1 is important where clinical signs caused by avirulent or virulent APMV-1s could be ambiguous. Understanding the diversity of APMV-1s circulating in GB is critical to understanding disease threat from these adaptable viruses.

The conclusions I seek to draw from this part of my investigations are:—

1. That a malarial form of horse-sickness probably occurs naturally.

2. That when animals which are either naturally relatively susceptible, such as the donkey, ox, and goat, or animals which have acquired protection, e.g. “salted” horses, are inoculated with virulent horse-sickness blood, their blood conveys a modified infection of horse-sickness which is malarial in type.

3. That this malarial from is associated with the presence of parasites within the red corpuscles of the blood of the infected animal.

4. That the blood of “salted” horse which have been previously regularly inoculated during several months is of a dangerous order of virulence. Vide former experiments.

5. That the blood of “salted” horses which have only been once inoculated after several months' rest conveys a fairly severe fever.

6. That the blood of “salted” horses, which have not been inoculated for even a year, can still convey infection.

7. That “unsalted” horses which have been inoculated a year previously with “salted” blood convey only a week infection.

8. That a severe attack of malarial horse-sickness gives a considerable degree of protection against subsequent inoculation with “salted” blood.

9. That when regularly inoculated “salted” horses are used to produce blood giving severe fever, such fever may become so severe as to cause death with symptoms of horse-sickness.

10. That the blood of the latter animals which die can produce virulent horse-sickness in clean horses, if used in a considerable dose, i.e. 20 c.c.

The results presented in this paper confirm the existence of two types of tetracycline resistance in Shigella sonnei. One group of strains had a high level of resistance to tetracycline and oxytetracycline, with a variable level of minocycline resistance. The second group had a lower level of tetracycline resistance and were sensitive to minocycline. After conjugation with E. coli K12 the selected E. coli transconjugants had the same levels of resistance as the parent Sh. sonnei strain, with one exception. Sh. sonnei 87 was resistant to a high level of tetracycline, but was able to transfer only low level resistance. It is suggested that Sh. sonnei 87 carries two plasmids: pSU1, a conjugative plasmid conferring a low level of tetracycline resistance, and pSU2, a non-conjugative plasmid which confers a high level of resistance to tetracycline.

The investigations which form the subject of this paper were undertaken at the Pasteur Institute, on the suggestion of M. Mesnil. It is a pleasure to acknowledge my great indebtedness to M. Mesnil for the help and advice he so willingly rendered me whilst I worked in his laboratory. M. Nicolle and he very kindly placed at my disposal their unique collection of colours, which had been supplied them by various firms (notably the Farbenfabriken of Elberfeld). By their suggestions, without which this work would not have been accomplished, they saved me much time and labour. MM. Nicolle and Mesnil had been studying the influence of a large number of colours on various trypanosomes, chiefly Trypanosoma Brucei and to a less extent T. Evansi, T. equinum, and T. Gambiense. Their work was undertaken after the publication of Ehrlich and Shiga's paper on the action of Trypanroth, one of the benzidine colours, on Trypanosoma equinum. M. Mesnil suggested that I should investigate the action of these colours on T. dimorphon which differs in many ways from the above trypanosomes.

To assess areas at risk for poliovirus circulation in Ecuador, we first selected provinces at highest risk based on low immunization coverage with three doses of oral poliovirus vaccine, and a low number of reported cases of acute flaccid paralysis (AFP). Subsequently, we reviewed discharge data for the period 1996–2000 for diagnoses compatible with AFP in the only two national referral hospitals in Quito, and at least two main hospitals in each of the six selected provinces. Environmental samples from one or two cities/towns in each selected province were tested for poliovirus. Of the 14 identified AFP-compatible cases, 8 (57%) had been previously reported and investigated. We visited four out of the six unreported cases; none of those four had sequelae compatible with poliomyelitis. From the 14 environmental samples taken, we identified Sabin viruses in six of the samples; no vaccine-derived polioviruses were isolated. Using this methodology, we found no evidence of undetected poliovirus circulation in Ecuador.

Transmission of varicella occurs frequently in schools and households. We investigated the characteristics of varicella cases derived from within-household transmission and the modes of varicella transmission between school and household settings in Shanghai, China, from 2009 to 2018. Within-household transmission occurred in 278 households, of which 134 transmission events were between children. Sixty-one household varicella transmission events may be attributed to isolation procedures for infected students during school outbreaks, and 7.6% of school outbreaks were caused by schoolchildren cases derived from within-household transmission. The frequency of ‘school-household-school’ transmission adds an additional layer of complexity to the control of school varicella outbreaks. Administration of varicella vaccine as post-exposure prophylaxis after exposure is considered to be an effective measure to control varicella spread within households and schools.

Resistance to beta-lactam antimicrobials caused by extended-spectrum beta-lactamase (ESBL)-producing organisms is a global health concern. The objectives of this study were to (1) summarise the prevalence of potential ESBL-producing Escherichia coli (ESBL-EC) and Salmonella spp. (ESBL-SA) isolates from agrifood and human sources in Canada from 2012 to 2017, and (2) describe the distribution of ESBL genotypes among these isolates. All data were obtained from the Canadian Integrated Program for Antimicrobial Resistance Surveillance (CIPARS). CIPARS analysed samples for the presence of ESBLs through phenotypic classification and identified beta-lactamase genes (blaTEM, blaSHV, blaCTX, blaOXA, blaCMY−2) using polymerase chain reaction (PCR) and whole genome sequencing (WGS). The prevalence of PCR-confirmed ESBL-EC in agrifood samples ranged from 0.5% to 3% across the surveillance years, and was detected most frequently in samples from broiler chicken farms. The overall prevalence of PCR-confirmed ESBL-SA varied between 1% and 4% between 2012 and 2017, and was most frequently detected in clinical isolates from domestic cattle. The TEM-CMY2 gene combination was the most frequently detected genotype for both ESBL-EC and ESBL-SA. The data suggest that the prevalence of ESBL-EC and ESBL-SA in Canada was low (i.e. <5%), but ongoing surveillance is needed to detect emerging or changing trends.

A total of 212 new members of the staff of the North-Eastern Fever Hospital were Schick and Moloney tested. The Schick-positive reactors were immunised with formol toxoid and post-Schick and Moloney tests were performed. The following conclusions were reached:

(1) The intradermal toxoid test of Moloney or Zoeller corresponds exactly with the pseudo response in the Schick test.

(2) The pseudo response is as efficient as the Moloney for detecting possible reactors to immunising doses of toxoid, and is a more accurate control of the Schick test. The Moloney therefore appears redundant.

(3) A positive MP (Moloney or pseudo) reaction accurately indicates those who will react to immunisation; but a negative MP is no guarantee that the subject will not react.

(4) The MP-reaction is evidence of bacterial hypersensitiveness to specific products of the body of the diphtheria bacillus.

(5) Zoeller's theory that hypersensitiveness is a half-way stage between susceptibility and immunity, is incorrect.

(6) MP-reactions usually, but not invariably, develop pari passu with immunity. Because of this parallelism tests of hypersensitiveness give information as to the state of immunity.

The significance of tests of infection, hypersensitiveness and immunity are considered; and the possible relationship of MP-reactions with bacterial immunity suggested.

In recent years, human leptospirosis has been reported in Jinping and Liping counties, Guizhou province, but the leptospires have never been isolated. To track the source of infection and understand the aetiological characteristics, we performed surveillance for field mice carriage of leptospirosis in 2011. Four strains of leptospire were isolated from Apodemus agrarius. PCR confirmed the four isolates as pathogenic. Multiple-locus variable-number tandem repeat analysis (MLVA) showed that the four strains were closely related to serovar Lai strain 56601 belonging to serogroup Icterohaemorrhagiae, which is consistent with the antibody detection results from local patients. Furthermore, the diversity of leptospiral isolates from different hosts and regions was demonstrated with MLVA. Our results suggest that A. agrarius may be the main carrier of Leptospira in Jinping and Liping counties, and the serogroup Icterohaemorrhagiae serovar may be the epidemic serogroup of Leptospira. This will contribute to the control and prevention of leptospirosis in these localities.

Few prospective studies have documented the seropositivity among those children infected with severe acute respiratory syndrome coronavirus 2. From 2 April 2021 to 24 June 2021, we prospectively enrolled children between the ages of 2 and 17 years at three North Carolina healthcare systems. Participants received at least four at-home serological tests detecting the presence of antibodies against, but not differentiating between, the nucleocapsid or spike antigen. A total of 1,058 participants were enrolled in the study, completing 2,709 tests between 1 May 2021 and 31 October 2021. Using multilevel regression with poststratification techniques and considering our assay sensitivity and sensitivity, we estimated that the seroprevalence of infection-induced antibodies among unvaccinated children and adolescents aged 2–17 years in North Carolina increased from 15.2% (95% credible interval, CrI 9.0–22.0) in May 2021 to 54.1% (95% CrI 46.7–61.1) by October 2021, indicating an average infection-to-reported-case ratio of 5. A rapid rise in seropositivity was most pronounced in those unvaccinated children aged 12–17 years, based on our estimates. This study underlines the utility of serial, serological testing to inform a broader understanding of the regional immune landscape and spread of infection.

Samples of frozen precooked rock lobster meat from five South Australian fish-processing plants situated in the West Coast and south-east regions were tested over a period of six months during the 1974/5 lobster fishing season. The most probable number (MPN) of E. coli and coliforms, Staphylococcus aureus and Salmonella, as well as total plate count (TPC) were determined in 480 samples. Monthly geometric mean TPC ranged from 1600/g to 25,000/g. The highest geometric mean of the MPN of coliforms and E. coli were 4·9/g and 1·8/g respectively. The highest geometric mean number of staphylococci was 18·6/g. Salmonella was not detected in the 480 units tested. Only 0·4% of the samples had TPC exceeding 100,000/g. Coliforms and E. coli were not present in 76·1% and 92·7% respectively of the samples tested. Staphylococcus aureus was not detected in 67·7% of the samples. The numbers of organisms in 82% of the samples fall within the microbiological standards proposed by the National Health and Medical Research Council of Australia for frozen precooked foods. The results of this study demonstrate the microbial quality of precooked lobster meat attainable when good manufacturing practices are used.

The numerical aspects of bacterial growth have hitherto been investigated chiefly in fluid media and the laws governing the development of bacterial populations in fluid cultures are known in some detail.

The aim of this study was to investigate the epidemiology of influenza A virus infection in Cyprus from the 2009 pandemic until 2013. Pandemic influenza A(H1N1)2009 virus infections outnumbered infections with other respiratory viruses until the end of 2009. The pandemic virus was also the prevalent influenza strain during influenza season 2010–2011; however, it was completely replaced by H3N2 subtype in the next season. During the most recent influenza season, 2012–2013, the pandemic strain was once again the only influenza A virus circulating in Cyprus. Full-length neuraminidase gene sequencing revealed mutations that had previously been identified as permissive. No significant difference in the expression of the IFN-inducible genes OAS and IFIT1 were observed. The phylogenetic analysis of the neuraminidase gene sequences revealed a picture of continuous importation of influenza strains in the island of Cyprus with local circulation playing only a minor role in determining the prevalent strain of the next influenza season.

As the on-going severe acute respiratory syndrome coronavirus 2 pandemic, we aimed to understand whether economic reopening (EROP) significantly influenced coronavirus disease 2019 (COVID-19) incidence. COVID-19 data from Texas Health and Human Services between March and August 2020 were analysed. COVID-19 incidence rate (cases per 100 000 population) was compared to statewide for selected urban and rural counties. We used joinpoint regression analysis to identify changes in trends of COVID-19 incidence and interrupted time-series analyses for potential impact of state EROP orders on COVID-19 incidence. We found that the incidence rate increased to 145.1% (95% CI 8.4–454.5%) through 4th April, decreased by 15.5% (95% CI −24.4 −5.9%) between 5th April and 30th May, increased by 93.1% (95% CI 60.9–131.8%) between 31st May and 11th July and decreased by 13.2% (95% CI −22.2 −3.2%) after 12 July 2020. The study demonstrates the EROP policies significantly impacted trends in COVID-19 incidence rates and accounted for increases of 129.9 and 164.6 cases per 100 000 populations for the 24- or 17-week model, respectively, along with other county and state reopening ordinances. The incidence rate decreased sharply after 12th July considering the emphasis on a facemask or covering requirement in business and social settings.

A comparative examination of the hippocampus and mid-brain in a series of 37 brains from suspected rabid animals has shown the marked superiority of the hippocampus as the site of election for Negri bodies.

Maternal infection in pregnancy is a known risk factor for adverse pregnancy outcome, and a number of zoonotic pathogens may constitute a risk to pregnant women and their fetuses. With animal contact as a proxy for the risk of zoonotic infection, this study aimed to evaluate pregnancy outcome in women with self-reported occupational or domestic contact with livestock compared to pregnant women without such contact. The Danish National Birth Cohort collected information on pregnancy outcome from 100 418 pregnant women (1996–2002) from which three study populations with occupational and/or domestic exposure to livestock and a reference group of women with no animal contact was sampled. Outcome measures were miscarriage, very preterm birth (before gestational week 32), preterm birth (before 37 gestational weeks), small for gestational age (SGA), and perinatal death. Adverse reproductive outcomes were assessed in four different exposure groups of women with occupational or domestic exposure to livestock with no association found between exposure to livestock and miscarriage, preterm birth, SGA or perinatal death. These findings should diminish general occupational health concerns for pregnant women with exposures to a range of different farm animals.

Migrants in Europe face a disproportionate burden of HIV infection; however, it remains unclear if this can be prevented through public health interventions in host countries. We undertake a systematic review and meta-analysis to estimate post-migration HIV acquisition (PMHA) as a proportion of all HIV cases in European migrants. MEDLINE, EMBASE, Global Health, HMIC, and Cochrane Library were searched with terms capturing ‘HIV’, ‘migration’, and ‘Europe’. Data relating to the proportion of HIV acquired following migration were extracted and random-effects model (REM) meta-analysis was undertaken to calculate a pooled estimate for the proportion of PMHA in European countries. Subgroup meta-analysis was undertaken for PMHA by migrant demographic characteristics and host country. Fifteen articles were included for systematic review following retrieval and screening of 2,320 articles. A total of 47,182 migrants in 11 European countries were included in REM meta-analysis, showing an overall PMHA proportion of 0.30 (95% CI: 0.23–0.38). Subgroup analysis showed no significant difference in PMHA between host country and migrant demographic characteristics. This work illustrates that migrants continue to be at high risk of HIV acquisition in Europe. This indicates the need for targeted screening and HIV prevention interventions, ensuring resources are appropriately directed to combat the spread of HIV.