The use of fumigants against insects attacking stored products involves two possible dangers. In the first place workers may be poisoned by inhaling the fumigant either during its use or its manufacture. Secondly the fumigant may be adsorbed onto food-stuffs thereby hazarding the health of consumers.

In a study of the influence of environmental and other conditions on the growth and nutrition of the children of the poorer classes in the city of Glasgow, it seemed desirable to determine how far a homogeneous stock was being dealt with since there was some danger that racial variations might modify the results of the investigation.

The purpose of the present study was to identify Echinococcus multilocularis infection in follow-up of 95 subjects initially seropostive by Emc-ELISA or Emf-ELISA antibody assays and to compare the utility of these assays with specific Em2plus-ELISA and ultrasound screening for E. multilocularis infection. At follow-up seven subjects were seropositive with both methods, while three were seropositive only with Emc-ELISA and 11 only with Emf-ELISA. All subjects were seronegative with Em2plus-ELISA. There were no manifestations of E. multilocularis infestation by ultrasonographic screening. Seropositivity on Emc-ELISA and Emf-ELISA screening tests does not appear to correlate with manifest alveolar echinococcosis identified by ultrasound. A recommendation for further follow-up of subjects found to be seropositive with Emc-ELISA and Emf-ELISA but with no sonographic evidence of disease is not justified at this time.

We report two cases of respiratory toxigenic Corynebacterium diphtheriae infection in fully vaccinated UK born adults following travel to Tunisia in October 2019. Both patients were successfully treated with antibiotics and neither received diphtheria antitoxin. Contact tracing was performed following a risk assessment but no additional cases were identified. This report highlights the importance of maintaining a high index of suspicion for re-emerging infections in patients with a history of travel to high-risk areas outside Europe.

The membrane methods described in Report 71 on the bacteriological examination of water supplies (Report, 1969) for the enumeration of coliform organisms and Escherichia coli in waters, together with a glutamate membrane method, were compared with the glutamate multiple tube method recommended in Report 71 and an incubation procedure similar to that used for membranes with the first 4 hr. at 30°C., and with MacConkey broth in multiple tubes. Although there were some differences between individual laboratories, the combined results from all participating laboratories showed that standard and extended membrane methods gave significantly higher results than the glutamate tube method for coliform organisms in both chlorinated and unchlorinated waters, but significantly lower results for Esch. coli with chlorinated waters and equivocal results with unchlorinated waters. Extended membranes gave higher results than glutamate tubes in larger proportions of samples than did standard membranes. Although transport membranes did not do so well as standard membrane methods, the results were usually in agreement with glutamate tubes except for Esch. coli in chlorinated waters. The glutamate membranes were unsatisfactory. Preliminary incubation of glutamate at 30° C. made little difference to the results.

This study aimed to assess the impact of the introduction of pneumococcal conjugate vaccine 13 (PCV13) on the molecular epidemiology of invasive pneumococcal disease (IPD) in children from Andalusia. A population-based prospective surveillance study was conducted on IPD in children aged <14 years from Andalusia (2018–2020). Pneumococcal invasive isolates collected between 2006 and 2009 in the two largest tertiary hospitals in Andalusia were used as pre-PCV13 controls for comparison of serotype/genotype distribution. Overall IPD incidence rate was 3.55 cases per 100 000 in 2018; increased non-significantly to 4.20 cases per 100 000 in 2019 and declined in 2020 to 1.69 cases per 100 000 (incidence rate ratio 2020 vs. 2019: 0.40, 95% confidence interval (CI) 0.20–0.89, P = 0.01). Proportion of IPD cases due to PCV13 serotypes in 2018–2020 was 28% (P = 0.0001 for comparison with 2006–2009). Serotypes 24F (15%) and 11A (8.3%) were the most frequently identified non-PCV13 serotypes (NVT) in 2018–2020. Penicillin- and/or ampicillin-resistant clones mostly belonged to clonal complex 156 (serotype 14-ST156 and ST2944 and serotype 11A-ST6521). The proportion of IPD cases caused by PCV13 serotypes declined significantly after the initiation of the PCV13 vaccination programme in 2016. Certain NVT, such as serotypes 24F and 11A, warrant future monitoring in IPD owing to invasive potential and/or antibiotic resistance rates.

1. For the particular toxin tested, the intravenous m.l.d. for mice was 60 times and the intramuscular m.l.d. for mice 100 times, the guinea-pig sub cutaneous m.l.d.

2. Antitoxin has the same neutralising power for toxin in mice as in guinea-pigs.

The bacteria which maybe included together as the Gaertner Group are of considerable importance, comprising as they do most of the bacteria found in outbreaks of food poisoning and in paratyphoid fever, while they are etiologically concerned with a number of diseases in animals both domesticated and wild.

A new COVID-19 vaccine was introduced in a remarkably short period of time. Public and healthcare workers (HCWs) were concerned about the safety of the vaccine, especially in light of the use of new technologies. A review regarding attitudes towards COVID-19 vaccination found a 22.5% hesitancy rate among HCWs. Online anonymous questionnaires were delivered using a web-based surveying platform to community HCWs in a central district in Israel from 3 to 19 January 2021. The real COVID-19 vaccination data were collected between the beginning of the vaccination rollout and the end of the month after the survey as well as the real vaccination rate among the general population. Of the 3,172 HCWs, 549 (17%) responded to the questionnaire. The highest positive attitude towards the vaccine was among physicians (95%), while nurses showed the highest level of hesitation (14%) for a specific sector (P < 0.05). However, the real vaccination rates were similar among physicians (63%) and nurses (62%). Surprisingly, the total vaccination rate of HCWs was substantially lower (52%) than that of the general population (71%). The main vaccination motivators were the social and economic effects of the COVID-19 epidemic. Focused strategies to reduce the level of hesitancy among HCWs are needed.

An LD 50 dose S. typhi (strain Ty was injected intraperitoneally into white mice, and the number of micro-organisms was determined after 1 min. and subsequently, in the blood, and after 3 hr. and subsequently, in the spleen and liver. The course of the infection was observed for 34 days.

The number of bacteria gradually increased in the blood stream during the first post-infective hours. It was possible to differentiate by external signs from the sixth post-infective hour and onwards between sick animals and recovering ones. This difference corresponded to the bacterial concentration in the blood stream and internal organs.

In the sick animals the increase in the bacterial count of blood stream continued till 9–10 hr. after the inoculation, when it reached its first peak. During the following 8 hr. a clear decrease in the blood count was evident which was attributed to the ‘clearing mechanism’ of the blood. The onset of a new bacterial rise in the blood stream appeared 18 hr. after the inoculation and reached a second peak during the further 6–8 hr.

In contrast to the observed decrease in the bacterial blood count, a steady and gradual increase in the count of the internal organs was seen; it was steadily progressive till the exitus.

In the recovering animals a steady decrease in the bacterial blood count was recorded. Between 24 and 26 hr. the number of micro-organisms in the blood and spleen was found to be 400 times less in the recovering animals than in the moribund ones. From 48 hr. and onwards a slow and gradual decrease in the bacterial count of the surviving animals was observed. The blood became sterile after 25 days. In the spleen and liver of the surviving animals after 48 hr. a new increase in the bacterial count is evident, accompanied by hyperplasia of the spleen. The number of bacteria reached a new peak in the liver on the third day and in the spleen on the fourth day after the infection.

Subsequently a slow and gradual decrease in the bacterial count was observed in both organs, but even after 34 days a small number of persisting bacteria in the spleen and liver tissue may be found.

We are still in doubt regarding the exact position of those bacilli which, morphologically and culturally, appear to be identical with the Klebs-Loeffler bacillus but which differ from it only in the absence of specific pathogenic power for laboratory animals. Most writers regard such non-virulent strains as true diphtheria bacilli which have lost their virulence and toxigenic power either temporarily or permanently. Others however are inclined to place them in a group allied to that of the genuine Klebs-Loeffler bacillus and express doubts as to whether they at any time possessed a claim to pathological significance (Graham Smith, 1904).

A reassortant swine-origin A(H3N2) virus (A/swine/BinhDuong/03-9/2010) was detected through swine surveillance programmes in southern Vietnam in 2010. This virus contains haemagglutinin and neuraminidase genes from a human A(H3N2) virus circulating around 2004–2006, and the internal genes from triple-reassortant swine influenza A viruses (IAVs). To assess population susceptibility to this virus we measured haemagglutination inhibiting (HI) titres to A/swine/BinhDuong/03-9/2010 and to seasonal A/Perth/16/2009 for 947 sera collected from urban and rural Vietnamese people during 2011–2012. Seroprevalence (HI ⩾ 40) was high and similar for both viruses, with 62·6% [95% confidence interval (CI) 59·4–65·7] against A/Perth/16/2009 and 54·6% (95% CI 51·4–57·8%) against A/swine/BinhDuong/03-9/2010, and no significant differences between urban and rural participants. Children aged <5 years lacked antibodies to the swine origin H3 virus despite high seroprevalence for A/Perth/16/2009. These results reveal vulnerability to infection to this contemporary swine IAV in children aged <5 years; however, cross-reactive immunity in adults would likely limit epidemic emergence potential.

The pathological histology of plague in man and experimental plague in animals has already been the subject of several researches, notably those of Aoyama (1896), Yamagiwa (1897), Albrecht and Gohn (1897), Dürck (1904) and Hamdi (1904) in the case of human plague, and of van der Stricht (1897), Honl (1897), Lustig and Zardo (1897), Babes and Livadite (1897), Albrecht and Gohn (1900) and Sata (1900) in the case of experimental plague.

In February and in June 1998, two people developed acute hepatitis B following in-patient care in a district general hospital. Initial enquiries indicated their infections were not attributable to staff undertaking exposure-prone procedures (EPPs). We report the findings and implications of the subsequent investigation: a multi-disciplinary, multi-agency investigation, including molecular epidemiological analysis. Occupational Health records showed that staff involved in EPPs with the patients were HBsAg negative. No contact between the patients was identified nor were there failures in sterilization. The patients' HBV strains were identical, indicating a common source. A total of 231 out of 232 staff who might have treated either patient were tested for HBsAg; the remaining doctor, working abroad, was HBsAg- and HBeAg-positive and had the same HBV strain as the patients. On two occasions the doctor's hand had been cut while breaking glass vials, but there was no documentation linking these events to the two patients. The doctor had been vaccinated in 1993 and tested for anti-HBs prior to commencing work in 1997. The doctor was recalled to Occupational Health but did not attend and was not followed up. In total, 4948 patients potentially treated by the doctor received an explanatory letter and 3150 were tested for HBsAg. Only one was positive, and HBV sequencing showed no link to the doctor. Occasionally transmission of HBV from heath-care workers can occur in a non-EPP setting and the implications of this require examination by those setting national policy. Occupational Health Services should investigate clinical heath-care workers who do not respond to vaccination. They should ensure HBV carriers are identified and offer them appropriate advice to prevent transmission to patients.

The distribution of serogroups of thermophilic campylobacters isolated in Israel from human patients (2421 isolates), chicken (942), turkeys (158), cattle (398), wild birds (234) and other sources, was studied.

Among the human isolates, 74 ROG-serogroups were identified. The six most commonly isolated of these (1,18; 11; 12; 8,23; 4 and 5,39) were found frequently in chickens. Only four common serogroups in man were also common in cattle, three in turkeys and two in wild birds.

Two common serogroups in man (1,18 and 5,39) were prevalent all over the country, while others were regionally distributed. When the prevalence of different serogroups in Israel was compared to that in Canada, some groups were common to both countries and others were common in only one or the other.

Campylobacter jejuni accounted for 86·7% to 92·1% of the isolates from man, chickens, turkeys, cattle and most of the wild birds. C. coli was found in 34·4% of isolates from cattle egrets and in 70·5% of those from pigs.

The dengue virus type 3 (DENV-3) homotypic outbreak cycles reported in Klang Valley, Malaysia in 1992–1995 and 2002 demonstrated different epidemic magnitude and duration. These outbreak cycles were caused by two closely related strains of viruses within the DENV-3 genotype II (DENV-3/II). The role of viral genotypic diversity and factors that could have influenced this phenomenon were investigated. The serum neutralisation sensitivity of DEN3/II strains responsible for the DENV-3 outbreak cycles in 1992–1995 and 2002 were examined. Representative virus isolates from the respective outbreaks were subjected to virus neutralisation assay using identified sera of patients with homotypic (DENV-3) or heterotypic dengue infections (DENV-1 and DENV-2). Results from the study suggested that isolates representing DENV-3/II group E (DENV-3/II-E) from the 1992–1995 outbreak and DENV-3/II group F (DENV-3/II-F) from the 2002 outbreak were neutralised at similar capacity (intergenotypic differences <2-fold) by sera of patients infected with DENV-3, DENV-1 and DENV-2/Asian genotypes. Sera of the DENV-2/Cosmopolitan infection efficiently neutralised DENV-3/II-F (FRNT50 = 508.0) at a similar neutralisation capacity against its own homotypic serotype, DENV-2 (FRNT50 = 452.5), but not against DENV-3/II-E (FRNT50 = 100.8). The different neutralisation sensitivities of DENV-3/II strains towards the cross-reacting DENV-2 heterotypic immunity could play a role in shaping the DENV-3 recurring outbreaks pattern in Malaysia. Two genetic variations, E-132 (H/Y) and E-479 (A/V) were identified on the envelope protein of DENV-3/II-E and DENV-3/II-F, respectively. The E-132 variation was predicted to affect the protein stability. A more extensive study, however, on the implication of the naturally occurring genetic variations within closely related DENV genotypes on the neutralisation profile and protective immunity would be needed for a better understanding of the DENV spread pattern in a hyperendemic setting.

Legionellosis is a disease caused by the bacterium Legionella that most commonly presents as Legionnaires’ disease (LD), a severe form of pneumonia. From 2015 to 2019, an average of 438 LD cases per year were reported in Canada. However, it is believed that the actual number of cases is much higher, since LD may be underdiagnosed and underreported. The purpose of this study was to develop an estimate of the true incidence of illnesses, hospitalizations, and deaths associated with LD in Canada. Values were derived using a stochastic model, based on Canadian surveillance data from 2015 to 2019, which were scaled up to account for underdiagnosis and underreporting. Overall, there were an estimated 1,113 (90% CrI: 737–1,730) illnesses, 1,008 (90% CrI: 271–2,244) hospitalizations, and 34 (90% CrI: 4–86) deaths due to domestically acquired waterborne LD annually in Canada from 2015 to 2019. It was further estimated that only 36% of illnesses and 39% of hospitalizations and deaths were captured in surveillance, and that 22% of illnesses were caused by Legionella serogroups and species other than Legionella pneumophila serogroup 1 (non-Lp1). This study highlights the true burden and areas for improvement in Canada’s surveillance and detection of LD.

The work began with efforts to isolate a type II Vi phage from local sewage. When this attempt failed, typing material was obtained from Dr J. Craigie and Dr A. Felix.

The typing method was applied to 495 strains of typhoid bacilli, the technique laid down by Craigie being followed throughout.

It was found that in South Africa the distribution of the various types of typhoid bacilli is different from that obtaining in other countries where this typing method has so far been applied.

During further investigations of type F strains the fact came to light that by means of a simple biochemical test type F strains can be subdivided into two sub-types, which subdivision will be useful in further epidemiological work. No such biochemical subdivision was found possible in any other type.

It did not prove possible to type all South African strains with the available phage preparations. Some of these strains must represent new types. Workers in other countries have had similar experiences and it will become necessary to compare all these unusual strains directly with one another in order to reach uniformity in nomenclature. It has already been possible to co-operate with workers in England, and they have been assisted by my finding that a strain, unique in England and supposed to have been brought there by a carrier, who had typhoid fever in South Africa 40 years ago, was endemic in South Africa.

During the course of the work, two outbreaks of typhoid fever occurred in which the typing method proved most useful, not only for linking up a particular carrier with a particular outbreak, but also for excluding an already known carrier who was under grave suspicion.

I have to thank Dr Craigie and Dr Felix for supplying material, and Prof. Pijper, of the Pretoria University, for placing laboratory facilities at my disposal. I thank all others for cultures received for typing.

In this study, we describe the results of virological investigations carried out on cases of gastroenteritis reported in different communities within a 2-year pilot surveillance programme (January 2012 to December 2013) in the autonomous province of Bolzano (Northern Italy). Among the 162 norovirus (NoV)-positive cases out of 702 cases investigated, 76 were grouped in nine suspected outbreaks, 37 were hospital-acquired and 49 were community-acquired sporadic cases. NoV infections were found in all age groups in outbreak and community-acquired cases, while the highest peak of hospital-acquired infections occurred in the elderly. Sequence analyses helped to identify suspected outbreaks both in the community and in hospital wards. Although GII.4 is the predominant genotype, sequence data confirmed that at least seven genotypes circulate causing sporadic cases. Findings in this study confirmed the relevance of NoV infections as a cause of outbreaks, and impact of NoV infections in community-acquired sporadic cases in adults that are rarely described because of a lack of reporting.

This paper presents the results of a preliminary study of conditions affecting the movement of leucocytes. It demonstrates experimental facts which confirm the assumptions that osmotic force present in aqueous solutions and the permeability of leucocytes for water are the factors responsible for the movement of these cells from place to place.