This study was a retrospective multicentre cohort study of patients with coronavirus disease 2019 (COVID-19) diagnosed at 24 hospitals in Jiangsu province, China as of 15 March 2020. The primary outcome was the occurrence of acute respiratory failure during hospital stay. Of 625 patients, 56 (9%) had respiratory failure. Some selected demographic, epidemiologic, clinical and laboratory features as well as radiologic features at admission and treatment during hospitalisation were significantly different in patients with and without respiratory failure. The multivariate logistic analysis indicated that age (in years) (odds ratio [OR], 1.07; 95% confidence interval [CI]: 1.03–1.10; P = 0.0002), respiratory rate (breaths/minute) (OR, 1.23; 95% CI: 1.08–1.40; P = 0.0020), lymphocyte count (109/l) (OR, 0.18; 95% CI: 0.05–0.69; P = 0.0157) and pulmonary opacity score (per 5%) (OR, 1.38; 95% CI: 1.19–1.61; P < 0.0001) at admission were associated with the occurrence of respiratory failure. Older age, increased respiratory rate, decreased lymphocyte count and greater pulmonary opacity score at admission were independent risk factors of respiratory failure in patients with COVID-19. Patients having these risk factors need to be intensively managed during hospitalisation.

1. During the summer months 1928–9 an epizootic occurred in De Aar and neighbouring districts among small veld rodents, mainly affecting Namaqua gerbilles (Desmodillus auricularis).

2. Many of the animals dying showed a haemorrhagic septicaemia, the causative organism of which appeared to be a Pasteurella rather smaller in size than Pasteurella (Bacillus) pestis.

3. In a considerable proportion of the animals found dead there was no obvious septicaemia.

4. A description is given of the Pasteurella, which is believed to be a hitherto undescribed species, and for which the name Pasteurella desmodilli is suggested.

5. This organism was found to be highly pathogenic for rabbits, less so for guinea-pigs and mice, and non-pathogenic for rats and fowls.

6. It was found by Rhodes to be highly pathogenic for Lobengula gerbilles (Tatera lobengulae) from Cape Town, but for animals of this species from Johannesburg it proved to be much less virulent, and even when it killed them there was frequently no septicaemia.

7. The above observation seems to indicate the presence of a considerable degree of immunity among the Johannesburg lobengulas, as compared with those from Cape Town.

8. It is suggested that a similar condition of partial immunity among the Namaqua gerbilles (for which there is other evidence adduced) might account for the finding of many of them dead without obvious septicaemia.

9. The existence of this disease introduces a complication in the diagnosis of plague among veld rodents.

A restriction fragment length polymorphism (RFLP) assay was developed to examine the genetic relationship between 67 (29 Indian, 38 global) rotavirus isolates of human, bovine and porcine neonates. The assay involved direct digestion of RT–PCR amplified VP7 cDNAs with three restriction enzymes (VspI, HaeIII, NlaIV) independently. Forty-eight RFLP patterns were identified for all 67 strains, and of these 20 patterns were associated with Indian isolates. A correlation between the restriction patterns and G type was apparent through deduction of enzyme restriction sites from known sequences. Major G serotypes (G1, G2, G6, G8) with a few mixed types could be differentiated where there was a positive assortment of intrinsic serotypes from multiple host origin, and certain single or combined enzyme profiles were highly dominant in the population. Significant genetic variations were established between global and Indian isolates and none of the RFLP patterns were shared between them. These data suggest that the Indian wild-type rotavirus population is distinguishable based on the VP7 gene, and co-circulation of distinct strains in different hosts is foremost, indicating the possible likelihood of inter-species transmission.

The poliomyelitis epidemic of 1937 in Denmark was investigated by means of information obtained about each individual case.

It occurred in the usual season, culminating in September. The districts involved were limited largely to Zealand, including Copenhagen. It is of particular interest that the disease occurred also in rural districts that were the sites of similar epidemics in 1933 and 1934.

It is noted as a peculiar fact that poliomyelitis seems to be unable to invade the whole of Denmark within one season.

The 1937 epidemic comprised 1200 notified cases, of whom 599 developed paralysis and 113 died. Everything suggests that the number of non-paralytic cases was far greater than the number of cases notified. Influenza and angina were notified with striking frequency in the districts where poliomyelitis prevailed.

The morbidity, frequency of paralysis and mortality were greater among males than among females.

A change in the age distribution during the past 35 years is pointed out. In 1937, 30% of the patients were over 15 years, and about 14% over 20 years; of those who died 45% were over 15 years, 20% over 20 years.

Convalescent serum was not employed in Copenhagen, but in the provinces 489 patients were treated with, and 400 without, serum. The principles of the treatment were the same as in 1934. Serum was given early in the disease, as a rule intravenously.

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.

The supernatant fluids of batch and continuous cultures of Brucella strains contained up to 100 mg/i of soluble RNA which could be recovered by precipitation with lysozyme. This RNA fraction had many of the properties of ribosomal RNA and was single-stranded, sensitive to ribonuclease, with an approximate sedimentation constant of 5S, a molecular weight of about 35000 daltons and an adenine; guanine; cytosine; uracil content of 17·5 26·5 33; 23 mol% respectively. RNA fractions from lysozyme precipitates evoked high titres of Brucella agglutinins on injection into rabbits and induced acute inflammatory responses in guinea-pig skin. Highly purified RNA fractions prepared by phenol extraction of lysozyme precipitates did not evoke antibodies to Brucella abortus.

The laboratory method here outlined and utilized by us over the past 11 years, of examining and judging ice-cream on a milk basis, appears to pro-vide a sieve of mesh generous enough to let through the passably ‘fit’ while stopping the presumably ‘doubtful’ and ‘unfit’.

Eighty-six samples of Alexandria milk ice-creams collected from various vendors in the city by Army Inspectors during the autumn months of 1944 showed, on this method, about 19% ‘unfit’—a result in remarkable agreement with fifty-eight samples from Municipal sampling, collected earlier in the year during summer months, which showed 16% ‘unfit’.

A small number of samples collected after hygienic control of the process of manufacture by Army Inspectors resulted in a total disappearance of unfit samples. The improvement arising from this controlled experiment was estimated at a lowering of 60% in total bacteria per c.c., and a reduction of 77% in coliforms.

The results of the latter experiment show what good results can be achieved in the betterment of milk ice-creams by simple hygienic measures, and should be more widely known in all centres where members of the Services are large consumers of ice-cream.

Acknowledgements are due to Lieut. J. T. S. Templeman, R.A.M.C., and his staff for their part in this investigation; and to Lieut.-Col. G. P. M. Marshall, R.A.M.C., A.D.H., for instigating the experiments on hygienic control of production.

1. In Hong Kong, where scarlet fever is extremely rare, the Dick reactions of a random sample of 921 Chinese were ascertained. Positive reactions were obtained in 19·1 per cent. The distribution of positive reactors in different age groups is recorded; it bears a general similarity to those recorded by various observers in Europe and the U.S.A.

2. A haemolytic streptococcal carrier rate of 6·6 per cent, was determined by nasopharyngeal swabbing of 1600 Hong Kong Chinese. The frequency of haemolytic streptococci was higher during the cooler months of the year and among the younger age groups.

3. Erythrogenic toxin production and fibrinolytic activity were demonstrated in a number of the strains of streptococci isolated from apparently normal throats.

4. The significance of these findings is discussed.

The COVID-19 pandemic has presented a unique opportunity to understand how real-time pathogen genomics can be used for large-scale outbreak investigations. On 12 August 2021, the Australian Capital Territory (ACT) detected an incursion of the SARS-CoV-2 Delta (B.1.617.2) variant. Prior to this date, SARS-CoV-2 had been eliminated locally since 7 July 2020. Several public health interventions were rapidly implemented in response to the incursion, including a territory-wide lockdown and comprehensive contact tracing. The ACT has not previously used pathogen genomics at a population level in an outbreak response; therefore, this incursion also presented an opportunity to investigate the utility of genomic sequencing to support contact tracing efforts in the ACT. Sequencing of >75% of the 1793 laboratory-confirmed cases during the 3 months following the initial notification identified at least 13 independent incursions with onwards spread in the community. Stratification of cases by genomic cluster revealed that distinct cohorts were affected by the different incursions. Two incursions resulted in most of the community transmission during the study period, with persistent transmission in vulnerable sections of the community. Ultimately, both major incursions were successfully mitigated through public health interventions, including COVID-19 vaccines. The high rates of SARS-CoV-2 sequencing in the ACT and the relatively small population size facilitated detailed investigations of the patterns of virus transmission, revealing insights beyond those gathered from traditional contact tracing alone. Genomic sequencing was critical to disentangling complex transmission chains to target interventions appropriately.

Enteric illness outbreaks are complex events, therefore, outbreak investigators use many different hypothesis generation methods depending on the situation. This scoping review was conducted to describe methods used to generate a hypothesis during enteric illness outbreak investigations. The search included five databases and grey literature for articles published between 1 January 2000 and 2 May 2015. Relevance screening and article characterisation were conducted by two independent reviewers using pretested forms. There were 903 outbreaks that described hypothesis generation methods and 33 papers which focused on the evaluation of hypothesis generation methods. Common hypothesis generation methods described are analytic studies (64.8%), descriptive epidemiology (33.7%), food or environmental sampling (32.8%) and facility inspections (27.9%). The least common methods included the use of a single interviewer (0.4%) and investigation of outliers (0.4%). Most studies reported using two or more methods to generate hypotheses (81.2%), with 29.2% of studies reporting using four or more. The use of multiple different hypothesis generation methods both within and between outbreaks highlights the complexity of enteric illness outbreak investigations. Future research should examine the effectiveness of each method and the contexts for which each is most effective in efficiently leading to source identification.

Multidrug-resistant Pseudomonas aeruginosa (MDRPA) infections are major threats to healthcare-associated infection control and the intrinsic molecular mechanisms of MDRPA are also unclear. We examined 348 isolates of P. aeruginosa, including 188 MDRPA and 160 non-MDRPA, obtained from five tertiary-care hospitals in Guangzhou, China. Significant correlations were found between gene/enzyme carriage and increased rates of antimicrobial resistance (P < 0·01). gyrA mutation, OprD loss and metallo-β-lactamase (MBL) presence were identified as crucial molecular risk factors for MDRPA acquisition by a combination of univariate logistic regression and a multifactor dimensionality reduction approach. The MDRPA rate was also elevated with the increase in positive numbers of those three determinants (P < 0·001). Thus, gyrA mutation, OprD loss and MBL presence may serve as predictors for early screening of MDRPA infections in clinical settings.

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.

The clinical and microbiological characteristics of catheter-related bloodstream infection (CR-BSI) due to uncommon microorganisms was assessed in a retrospective case-control study over a 9-year period in a tertiary teaching hospital. Uncommon microorganisms were defined as those representing <0·5% of all CR-BSI. Diagnosis of CR-BSI required that the same microorganism was grown from at least one peripheral venous blood culture and a catheter tip culture. Thirty-one episodes of CR-BSI were identified due to 13 different genera and these accounted for 2·3% of all CR-BSI in the hospital. Although these infections were not associated with increased mortality, they occurred in patients with more severe underlying conditions who were receiving prolonged antibiotic therapy.

An epidemiological study and the simultaneous evaluation of anti-Hav antibody using radio immunoassay (RIA) and immunoadherence hemagglutination assay (IAHA) was performed during three hepatitis A epidemics in the Tours area (France). Fifty-seven sera from 35 subjects with viral hepatitis type A and 16 sera from nine children who did not develop any clinical signs of hepatitis were studied. The more explosive epidemic occurred in an institution for mentally retarded children (attack rate 68%). The two major outbreaks observed were due to the introduction in the institutions of individuals infected with hepatitis A virus. Two out of three of the index cases had a seafood dinner three to four weeks before onset of jaundice. Sera taken one week after jaundice were always found to be anti-HAV positive by both RIA and IAHA, and sera taken more than three days before the appearance of jaundice were negative by both methods. Sera taken at the peak of the transaminase elevation were anti-HAV positive by RIA but only one out of two were positive by Iaha. The anti-HAV titre by RIA increased from the time of the appearance of jaundice and the highest titres, over 1/20000 were seen only after several months. Observations of subjects in close contact with patients who seroconverted without any manifestation of hepatitis, confirmed the existence of clinically mute infections.

In July 2021, Public Health Wales received two notifications of salmonella gastroenteritis. Both cases has attended the same barbecue to celebrate Eid al–Adha, two days earlier. Additional cases attending the same barbecue were found and an outbreak investigation was initiated. The barbecue was attended by a North African community’s social network. On same day, smaller lunches were held in three homes in the social network. Many people attended both a lunch and the barbecue. Cases were defined as someone with an epidemiological link to the barbecue and/or lunches with diarrhoea and/or vomiting with date of onset following these events. We undertook a cohort study of 36 people attending the barbecue and/or lunch, and a nested case-control study using Firth logistic regression. A communication campaign, sensitive towards different cultural practices, was developed in collaboration with the affected community. Consumption of a traditional raw liver dish, ‘marrara’, at the barbecue was the likely vehicle for infection (Firth logistic regression, aOR: 49.99, 95%CI 1.71–1461.54, p = 0.02). Meat and offal came from two local butchers (same supplier) and samples yielded identical whole genome sequences as cases. Future outbreak investigations should be relevant to the community affected by considering dishes beyond those found in routine questionnaires.

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.

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.

The Traveller's Diarrhoea Network, by which the Infectious Disease Surveillance Center is electronically connected with two major airport quarantine stations and three infectious disease hospitals, was launched in February 1988 in Japan. The data on travellers' diarrhoea detected is reported weekly by e-mail. Two clusters of infection among travellers returning from Italy were reported by two airport quarantine stations at the end of September 1998. A total of 12 salmonella isolates from 2 clusters were examined. All were identified as Salmonella enteritidis, phage type 4 and showed identical banding patterns on pulsed-field gel electrophoresis. A case-control study showed that the scrambled eggs served at the hotel restaurant in Rome were the likely source of this outbreak. This outbreak could not have been detected promptly and investigated easily without the e-mail network. International exchange of data on travellers' diarrhoea is important for preventing and controlling food-borne illnesses infected abroad.

Sera from healthy blood donors from different parts of New Zealand, collected between 1977 and 1980, were analysed by the microagglutination technique for antibodies against Brucella abortus. Populations from both urban and rural areas were studied. The technique was shown to be capable of handling the 3351 sera studied and thus to be a useful screening test to assess the immune status of large populations. The results demonstrated some of the effects on the human population of the successful bovine brucellosis eradication programme.