In April 2020, Belgium experienced high numbers of fatal COVID-19 cases among nursing home (NH) residents. In response, a mass testing campaign was organised testing all NH residents and staff. We analysed the data of Flemish NHs to identify institutional factors associated with increased SARS-CoV-2 infection rates among NH residents. Cross-sectional study was conducted between 8 April and 15 May 2020. Data collected included demographics, group category (i.e. staff or resident), symptom status and test result. We retrieved additional data: number of beds and staff, type of beds (level of dependency of residents) and ownership (public, private for profit/non-profit institutions). Risk factor analysis was performed using negative binomial regression. In total, 695 NHs were included, 282 (41%) had at least one resident tested positive. Higher infection rate among residents was associated with a higher fraction of RVT beds, generally occupied by more dependent residents (incidence rate ratio (IRR) 1.97; 95% CI 1.00–3.86) and higher staff infection rate (IRR 1.89; 95% CI 1.68–2.12). No relationship was found between other investigated NH characteristics and infection rate among residents. Staff-resident interactions are key in SARS-CoV-2 transmission dynamics. Vaccination, regular staff testing, assessment of infection prevention and control strategies in all NHs are needed to face future SARS-CoV-2 epidemics in these settings.

A report is given of a milk epidemic of scarlatinal angina, comprising 118 cases of scarlet fever and about fifty cases of sore throat.

The infection was spread through contamination of the milk from a milkmaid with purulent otitis media after non-recognized scarlet fever.

On cultivation, Streptococcus pyrogenes, group A (Lancefield), type 3 (Griffith) was isolated from 108 of these patients and from pus from the ear of the milkmaid. The cows, on the other hand, and their milk were found to be normal (two examinations at an interval of 6 days).

Inquiry into the conditions under which the milk was transported from the producer via the dairy to the consumers and information concerning the distribution and consumption of the milk confirmed in all details the assumption as to the causal connexion between the otitis media in the milkmaid and the outbreak of the epidemic.

This epidemic furnishes an example of transmission of the infection from man directly through the milk to a fairly large number of consumers without any intermediate infection (mastitis) in the cows.

Clinically the cases in this epidemic may be said, on the whole, to be mild; still, one of the patients died of complicating bronchopneumonia.

FROM time to time certain organisms, all closely similar, have been encountered in this laboratory which from their unusual occurrence and unfamiliar behaviour presented some difficulty in their identification. An account of some of them and of the cases from which they were derived is here given, and an attempt is made to correlate the organisms. If the result of the investigation shows that they belong to a single group of pathogenic bacilli, the important fact will be illustrated from the short accounts of the cases that a wide range of clinical manifestations may be met with in association with this group of bacteria.

Past studies exploring risk factors for fluoroquinolone (FQ) resistance in urinary tract infections (UTIs) focused only on UTIs caused by Gram-negative pathogens. The epidemiology of FQ resistance in enterococcal UTIs has not been studied. We conducted a case-control study at two medical centres within the University of Pennsylvania Health System in order to identify risk factors for FQ resistance in enterococcal UTIs. Subjects with positive urine cultures for enterococci and meeting CDC criteria for healthcare-acquired UTI were eligible. Cases were subjects with FQ-resistant enterococcal UTI. Controls were subjects with FQ-susceptible enterococcal UTI and were frequency matched to cases by month of isolation. A total of 136 cases and 139 controls were included from 1 January 2003 to 31 March 2005. Independent risk factors [adjusted OR (95% CI)] for FQ resistance included cardiovascular diseases [2·24 (1·05–4·79), P=0·037], hospitalization within the past 2 weeks [2·08 (1·05–4·11), P=0·035], hospitalization on a medicine service [2·15 (1·08–4·30), P<0·030], recent exposure to β-lactamase inhibitors (BLIs) [14·98 (2·92–76·99), P<0·001], extended spectrum cephalosporins [9·82 (3·37–28·60), P<0·001], FQs [5·36 (2·20–13·05), P<0·001] and clindamycin [13·90 (1·21–10·49), P=0·035]. Use of BLIs, extended spectrum cephalosporins, FQs and clindamycin was associated with FQ resistance in enterococcal uropathogens. Efforts to curb FQ resistance should focus on optimizing use of these agents.

Annual H3N2 subtype influenza outbreaks in Guangdong, China are a severe public health issue and require ongoing monitoring of emerging viral variants. The variation and evolution of haemagglutinin (HA) and neuraminidase (NA) genes of influenza isolates from Guangdong during 2007–2011 and others from GenBank were analysed using Lasergene 7.1 and MEGA 5.05, and serological analysis of antigens was determined by haemagglutination inhibition (HI). Susceptibility to antiviral drugs was correlated with genetic mutations. Phylogenetic analysis and alignment of HA and NA genes were performed on 18 Guangdong isolates and 26 global reference strains. The non-synonymous (dN) evolutionary rate of HA1 was 3·13 times that of HA2. Compared with the A/Perth/16/2009 vaccine HA gene, homologies of Guangdong isolates were between 98·8–99·7% and 98·0–98·4% in 2009 and 2010, respectively. Amino-acid substitutions were found in five epitopes of HA1 from Guangdong isolates between 2007 and 2011, especially in epitopes B (N160K) and D (K174R/N). The K189E/N/Q and T228A mutations in the receptor-binding site (RBS) occurred in the 2010 strains, which affected the antigenicity of HA1. The antigenicity of the epidemic H3N2 isolates in 2010 was somewhat different from that of A/Perth/16/2009. The Guangdong H3N2 isolates were determined to be oseltamivir-resistant with IC50 of 0·396±0·085 nmol/l (n=17) and zanamivir-resistant with IC50 of 0·477±0·149 nmol/l (n=18). Variations were present in epitopes B and D, two sites in the RBS and two glycosylation sites in the Guangdong H3N2 HA1 gene. The majority of the Guangdong H3N2 isolates were sensitive to oseltamivir and zanamivir. Compared to the World Health Organization 2012 vaccine strains, Guangdong H3N2 strains varied genetically and antigenically to some degree.

We present two complementary model-based methods for calculating the risk of international spread of the novel coronavirus SARS-CoV-2 from the outbreak epicentre. One model aims to calculate the number of cases that would be exported from an endemic country to disease-free regions by travellers. The second model calculates the probability that an infected traveller will generate at least one secondary autochthonous case in the visited country. Although this paper focuses on the data from China, our methods can be adapted to calculate the risk of importation and subsequent outbreaks. We found an average R0 = 5.31 (ranging from 4.08 to 7.91) and a risk of spreading of 0.75 latent individuals per 1000 travellers. In addition, one infective traveller would be able to generate at least one secondary autochthonous case in the visited country with a probability of 23%.

This paper is written from the practical point of view of a laboratory worker who is daily in direct contact with the cases submitted to him for diagnosis. Its purpose is to prove the inefficiency of the Widal reaction as a diagnostic test, and to urge its replacement by a more satisfactory method. Such a method is to be found in the application of the discoveries and theories on agglutination of Weil and Felix (1920), Felix (1924 and 1929), and Felix and Olitzki (1928 and 1929).

The Antarctic provides unusually simplified conditions for the study of the persistence and exchange of micro-organisms of the upper respiratory tract. The work reported here was done while the author was in the Falkland Islands Dependencies Survey and the United States Antarctic Research Program.

Staph, aureus and Staph, albus persisted in the noses, and a-haemolytic streptococci in the throats of men throughout long periods of isolation and semi-isolation in Antarctica.

On the whole, men kept their own strains (phage types) of Staph, aureus despite living in very close contact with each other.

Persistent carriers of Staph, aureus (90% or more positive swabs per individual) continued to carry this organism for as long as 2 years in Antarctica. Data from men at Wilkes and Hallett IGY Stations indicated that there was a decrease in the intermittent and occasional carrier rates, resulting in a much lower total carrier rate after 12 months Antarctic isolation.

Evidence is presented to suggest that β-haemolytic streptococci had disappeared from throats after 12 months of isolation. It is thought that the absence of upper respiratory infections in these communities is due to absence of the bacterial or viral agents.

There is an urgent need for further work on the carriage of micro-organisms in the present unique epidemiological conditions of the Antarctic, and for better laboratory facilities there.

This study aimed to evaluate the incidence of Staphylococcus aureus infections in different departments of Belcolle Hospital in Viterbo and the surrounding area between January 2003 and June 2008. Isolates of methicillin-resistant S. aureus (MRSA) recovered in this time interval were characterized by microbiological and molecular methods to evaluate the reliability of simple criteria to distinguish between hospital-acquired and community-acquired isolates. MRSA accounted for 33% of all S. aureus, with a significantly higher prevalence in isolates from nosocomial infections. MRSA isolates were assayed by PCR for the presence of 13 genes associated with virulence, agr type and SCCmec type. Cumulative data were analysed by partial least square discriminant analysis and a clear correlation was demonstrated between genetic profiles and classification of isolates as hospital or community acquired according to simple temporal criteria. Nosocomial MRSA isolates from blood samples showed significantly higher genetic diversity than other nosocomial isolates. Our data confirm the existence of significant differences between community- and hospital-acquired MRSA isolates.

In Australia, hepatitis B (HBV) vaccination is recommended for injecting drug users (IDUs), Indigenous adults and prisoners. We compared immunity to HBV in prisoners and the general population obtained from national serosurveys in 2007. Individuals with HBV surface antibody (HBsAb) positive sera were considered immune from past infection [HBV core antibody (HBcAb) positive] or from vaccination (HBcAb negative). Male prisoners aged 18–58 years had a higher HBsAb seroprevalence than the general population (46·4% vs. 39·4%, P = 0·061). Comparison of HBcAb results was possible for males aged 18–29 years. In this group, higher HBsAb seroprevalence was due to past infection (12·9% vs. 3·0%, P < 0·001), rather than vaccine-conferred immunity (35·3% vs. 43·4%, P = 0·097). All prisoner groups, but especially IDUs, those of Indigenous heritage or those with a previous episode of imprisonment had higher levels of immunity from past infection than the general population (19·3%, 33·0%, 17·1%, respectively, vs. 3·0%, P < 0·05). Indigenous prisoners, non-IDUs and first-time entrants had significantly lower levels of vaccine-conferred immunity than the general population (26·4%, 26·2% and 20·7% respectively vs. 43·4%, P < 0·05). Improving prison-based HBV vaccination would prevent transmission in the prison setting and protect vulnerable members of the community who are at high risk of both infection and entering the prison system.

Serological surveys among representative population samples have proved rare given their reliance on invasive sample collection. We therefore completed the first population-based postal survey of immunity in England and Wales using new oral fluid technology. This paper examines the feasibility of this new methodological approach. Nearly 5500 oral fluid samples were collected, with individual demographic and social data via a questionnaire, from persons under 45 years of age recruited through general practices. Instructions were accurately followed with only 1% of samples returned without risk-factor data. The overall response rate was 40%. Response was independently associated with age, sex and location. Response was highest in children aged 5–14 years, adult females and in rural locations. This approach allowed the successful collection of comprehensive individual risk data, but response rates in adults must be improved if oral fluid surveys are to routinely complement serological surveillance.

Community-acquired Staphylococcus aureus infections are a public health concern, yet little is known about infections that do not present to hospital. We identified community-onset S. aureus infections via specimens submitted to a community-based pathology service. Referring doctors confirmed eligibility and described infection site, severity and treatment. Isolates were characterized on antibiotic resistance, PFGE, MLST/SCCmec, and Panton–Valentine leukocidin (PVL), representing 106 community-onset infections; 34 non-multiresistant methicillin-resistant S. aureus (nmMRSA) (resistant to <3 non-β-lactam antibiotics), 15 multiply antibiotic-resistant MRSA (mMRSA) and 57 methicillin-sensitive S. aureus (MSSA). Most (93%) were skin and soft tissue infections. PVL genes were carried by 42% of nmMRSA isolates [95% confidence interval (CI) 26–61] and 15% of MSSA (95% CI 8–28). PVL was associated with infections of the trunk, head or neck (56·4% vs. 24·3%, P = 0·005) in younger patients (23 vs. 52 years, P < 0·001), and with boils or abscesses (OR 8·67, 95% CI 2·9–26·2), suggesting underlying differences in exposure and/or pathogenesis.

The lack of information on the immunity of adults in Brazil against diphtheria prompted us to analyse sera from 234 blood donors aged 18–61 years (30·3% females and 69·7% males). IgG diphtheria antitoxin levels determined by means of an ELISA, validated by toxin neutralization test in Vero cells, showed that 30·7% (95% CI 25·0–37·1) of the population was fully protected ([ges ]1 IU/ml). The highest percentage of subjects fully protected was in the 31–40 years age group. Most of the subjects with uncertain or no protection (<1 IU/ml) were found in the 18–30 years age group (43·8%, OR 2·18, P=0·01). Antitoxin levels were not influenced by the increase in age. Males were more protected than females (80·5%, OR 0·44, P=0·01). The prevalence of 30% of individuals fully protected against diphtheria in blood donors in Rio de Janeiro supports the fact that immunity to diphtheria among healthy Brazilian adults is inadequate. To avoid diphtheria epidemics in the future the immunity among adults should be raised in the coming years.

1. An epidemic of a dysenteroid nature, largely ambulatory, due to B. dysenteriae (Sonne), affecting some 100 nurses without transference to any hospital case in the wards served by this section of the nursing staff, is described.

2. Sonne's bacillus was isolated from sixteen out of forty-two cases examined.

3. The probable cause was infection of food during preparation in the kitchens by a carrier.

4. A case of infection from laboratory cultures is described.

5. Notes are given of investigations upon the colonial appearance, biochemical and agglutinogenic reactions and pathogenicity to rabbits of the organism isolated, and also upon the presence of agglutinins in the blood of infected cases.

6. One case of infection in a rabbit by feeding experiments is described.

No evidence of vaccine virus transmission was found in two studies where Wistar RA 27/3 rubella vaccine was administered intranasally. Vaccine was immunogenic in all of 23 vaccinated children in one study, while in the other only 5 of the 11 vaccinees developed antibody. The reduced seroconversion rate in the latter study appears to have been caused by one or a combination of factors, including the vaccination technique, the presence of infective nasal conditions in vaccinees and the titre of vaccine used.

When mussels are allowed to function in sea water the main changes occurring in the water are depletion of dissolved oxygen and lowering of pH value. Provided the faeces and pseudo-faeces are not disturbed the increase in the content of organic matter is not appreciable. If the supernatant water is removed and aerated with diffused air the water is re-oxygenated, the pH value is restored to its original level, and the water so treated may be re-used for immersing a fresh batch of mussels. The process of re-use may apparently be continued indefinitely.

Under these conditions a high degree of cleansing is achieved by the mussels, the count of coli-aerogenes bacteria being reduced to a small fraction of the original; counts of bacteria in the water, on the other hand, are subject to large fluctuations. It was considered advisable for this reason to chlorinate the water between each cycle of cleansing in order to immerse the mussels on each occasion in water which itself was reasonably certain to be free from coliform bacteria, potentially including pathogens.

Experience showed that the greatest difficulty involved in the use of chlorine was in removing residual chlorine so that it would not inhibit functioning of the mussels when the water was re-used. After trials of various alternatives it was concluded that the most satisfactory method was to determine by means of small-scale tests the smallest quantity of chlorine (below the break-point) required to give a residual concentration of 0·05–0·10 p.p.m. in the re-used water and then to add the corresponding quantity with precision to the bulk of water by means of a dosing apparatus while the water was being pumped from the mussel tank to the aeration tank. After a period of contact of 1 hr. the water was aerated for a further hour. A series of trials in a semll-scale plant showed that this treatment ensured that residual chlorine in the water being added to the mussels did not exceed 0·05 p.p.m.; as a result the mussels functioned satisfactorily and the degree of cleansing attained was comparable with that attained in the existing mussel-cleansing tanks in which sterilized fresh sea water is used for each cycle of cleansing. Although the concentration of residual chlorine was small the mussels kept the water so clear that this concentration was effectively bactericidal and the bacterial quality of the water was usually comparable with that of good drinking water. Low temperatures retard the metabolic activity of mussels and below 4° C. this is so marked that the degree of cleansing achieved is unsatisfactory. For this reason it is recommended that the temperature of the re-used water should be maintained at 6° C. (43° F.) or above.

Oysters were found to be satisfactorily cleansed by a process of re-use similar to that adopted for mussels, provided the temperature of the water was maintained at 54° F. (12·2° C.) or rather higher.

Small-scale trials showed that artificial sea water, prepared by dissolving in fresh water suitable quantities of the major constituents of natural sea water, could be successfully re-used for cleansing mussels.

It is shown that the assay for infectivity in bits of allantois-on-shell, which has been standardized on the BEL strain, is optimal also for nine representative strains of influenza virus tested.

On the average, the sensitivity of the technique is the same as of orthodox allantoic infectivity tests; its precision is always higher. The relative sensitivity of the two tests varies from strain to strain, the log tray/egg differences being SW (+0.88), MEL (+0.51), CAM (+0.31), PR8 (0.28), WSE (+0.25), HUT (−0.02), BEL (−0.22), FMI (−0.35), LEE (−0.47), BON (−1.02). This gradient is the same for fully infective and incomplete forms of influenza virus.

The tray/egg gradient of susceptibility is negatively correlated with the variation in host resistance.

The differences in susceptibility are not due to any effect of the plastic trays, to thermal inactivation of the virus, to differences in adsorption or viropexis in the two test systems or to the effect of allantoic fluid on the virus particle. The critical step has been shown to occur during the intracellular stage of multiplication.

Two cases of fatal melioidosis are described. The first a robust Indian labourer; the second a well-nourished, muscular European.

Case 1. Gradual onset. Irregular fever. Pain in the epigastrium. No physical signs of disease at first, except enlarged spleen; later, there were signs of consolidation at the bases of both lungs. Constipated at first; diarrhoea came on towards the end and the patient collapsed and died at the end of the third week.

At the autopsy; there were small patches of consolidation in the lungs, composed of minute suppurating tubercles. In the liver there were similar aggregations of small suppurating tubercles and two circumscribed abscesses. The gall-bladder was thickened. The spleen was enlarged and contained septic infarcts and abscesses. In the caecum there were small superficial ulcers. B. whitmori was cultivated from the lungs, spleen, liver and gall-bladder.

Animals were inoculated as follows: A guinea-pig, inoculated in the anterior nares with pus from the liver, died nine days later with caseous inflammation of the nasal passages and a caseous inguinal gland from which B. whitmori was recovered. A guinea-pig, inoculated subcutaneously with pus from the liver, died on the twenty-fifth day with abscesses in the lymphatic glands from which B. whitmori was cultivated. A guinea-pig, inoculated subcutaneously with a culture of the organism, died within sixteen hours from septicaemia. B. whitmori was recovered from the heart and spleen. A guinea-pig, inoculated subcutaneously with an attenuated culture, died on the twenty-fifth day with suppurating buboes and with abscesses in the liver and lungs from which B. whitmori was cultivated. Two horses were inoculated subcutaneously with cultures of the strain of B. whitmori cultivated from the patient. An abscess developed at the site of inoculation, in each case, but the local lesion healed and the animals have, so far, remained healthy.

Case 2. The illness commenced gradually with pain after food, occasional vomiting and looseness of the bowels. The temperature became high and of the swinging type, accompanied by rigors and sweats. The liver was enlarged. The patient died on the twenty-fifth day.

At the autopsy, two large abscesses were found in the liver, the gall-bladder was thickened and there were a few small superficial ulcers in the caecum. B. whitmori was cultivated from the liver abscess. No amoebae were found.

The following animals were inoculated. Two wild rats were inoculated subcutaneously with a culture from this case and both died from septicaemia in less than twenty-four hours. B. whitmori was recovered from the heart's blood. The result of the subcutaneous inoculation of a guinea-pig was the same. A guinea-pig, inoculated in the nostril, died on the fifth day with a cheesy deposit in the nose and septicaemia. Another guinea-pig, inoculated in the same way, but after the organism had been subcultivated repeatedly, died on the twelfth day, with caseous tracheal glands containing B. whitmori. A rabbit, inoculated subcutaneously, died in twenty-six hours from septicaemia with tubereles in the peritoneum. B. whitmori was cultivated from the peritoneum and from the heart's blood. A monkey fed on a culture remained healthy. A pony inoculated intravenously recovered after a week's fever.

1. An outbreak is described of fatal epidemic enteritis due to B. dysenteriae Sonne which occurred in the autumn, 1928, in the infant wards of a hospital in Glasgow.

2. The clinical histories of two fatal cases are given.

3. The bacteriological and immunological examination of two strains of B. dysenteriae Sonne is described.

4. The results are given of a series of animal inoculations undertaken to study the virulence of B. dysenteriae Sonne and the nature of the lesions which it produces. To these are added the results of certain feeding experiments.