Between March and July 2003, 671 cases of severe acute respiratory syndrome (SARS) were diagnosed in Taiwan with a total of 84 fatalities. After the epidemic, a serological survey was conducted involving the asymptomatic household contacts. Household contacts of 13 index patients were enrolled in the study. Contact history and clinical symptoms of the household contacts were recorded by standardized questionnaires. Blood samples of patients and household contacts were collected at least 28 days after symptom onset in the index patients or household exposure in the contacts for SARS-associated coronavirus (SARS-CoV) IgG testing. On the basis of this investigation, 29 persons (25 adults and 4 children) were identified as having had unprotected exposure to the index cases before infection-control practices were implemented. Laboratory evaluation of clinical specimens showed no evidence of transmission of SARS-CoV infection to any contacts. This investigation demonstrated that subclinical transmission among household contacts was low in the described setting.

Thin-layer chromatography (TLC) was compared with seroagglutination for subtyping of Mycobacterium avium complex (MAC) bacteria. Seventy-five significant MAC isolates from patients with AIDS were typed by both methods and 36 isolates, judged to be clinically non-significant, were examined by TLC only. Overall. 75% of isolates tested were typable by seroagglutination and 91% by TLC; the results correlated between the two except for minor discrepancies.

Serovars 1, 8 and 21 and mixed serovars 1–21 and 1–8–21 were common among isolates from AIDS patients and together represented 83 % of isolates compared with only 36% in the non-significant group (odds ratio 8·4; 95% confidence interval 3·4–23·3). This difference remained significant after exclusion of serovar 41 (M. scrofulaceum), which was the commonest isolate (28%) in the non-significant group but was not isolated from patients with AIDS.

TLC is useful to supplement seroagglutination for subtyping of MAC. Further study is required to determine whether apparent differences between isolates from patients with AIDS and from other sources reflect differences in virulence or in environmental prevalence of MAC subtypes.

With the use of streptomycin-resistant mutants to facilitate recovery, 5 strains of 4 species of Salmonella were shown to grow rapidly at 22° C. on low salt ham even from an inoculum of 10–20 organisms. S. pullorum did not grow well. All 6 strains of Salmonella survived but did not grow on ‘high salt ham’. We conclude that cooked ham containing approximately 2·8 g. NaCl/100 g. H2O once infected is more likely to give rise to food poisoning than is ham with the higher salt content traditionally used.

Xpert MTB/RIF (Xpert) is the preferred first-line test for all persons with tuberculosis (TB) symptoms in South Africa in line with a diagnostic algorithm. This study evaluates pre- and post-implementation trends in diagnostic practices for drug-sensitive, pulmonary TB in adults in an operational setting, following the introduction of the Xpert-based algorithm. We retrospectively analysed data from the national TB database for Greater Tzaneen sub-district, Limpopo Province. Trends in a number of cases, diagnosis and outcome and characteristics associated with death are reported. A total of 8407 cases were treated from 2008 until 2015, with annual cases registered decreasing by 31·7% over that time period (from 1251 to 855 per year). After implementation of Xpert, 69·9% of cases were diagnosed by Xpert, 29·4% clinically, 0·6% by smear microscopy and 0·1% by culture. Cases with a recorded microbiological test increased from 76·2% to 96·4%. Cases started on treatment without confirmation, but with a negative microbiological test increased from 7·1% to 25·7%. Case fatality decreased from 15·0% to 9·8%, remaining consistently higher in empirically treated groups, regardless of HIV status. Implementation of the algorithm coincided with a reduced number of TB cases treated and improved coverage of microbiological testing; however, a substantial proportion of cases continued to start treatment empirically.

Human bocaviruses (HBoVs) have been detected in human gastrointestinal infections worldwide. In 2005, HBoV was also discovered in infants and children with infections of the lower respiratory tract. Recently, several genotypes of this parvovirus, including HBoV genotype 2 (HBoV2), genotype 3 (HBoV3) and genotype 4 (HBoV4), were discovered and found to be closely related to HBoV. HBoV2 was first detected in stool samples from children in Pakistan, followed by detection in other countries. HBoV3 was detected in Australia and HBoV4 was identified in stool samples from Nigeria, Tunisia and the USA. Recently, HBoV infection has been on the rise throughout the world, particularly in countries neighbouring South Korea; however, there have been very few studies on Korean strains. In this study, we characterised the whole genome and determined the phylogenetic position of CUK-BC20, a new clinical HBoV strain isolated in South Korea. The CUK-BC20 genome of 5184 nucleotides (nt) contains three open-reading frames (ORFs). The genotype of CUK-BC20 is HBoV2, and 98.77% of its nt sequence is identical with those of other HBoVs, namely Rus-Nsc10-N386. Especially, the ORF3 amino acid sequences from positions 212–213 and 454 corresponding to a variable region (VR)1 and VR5, respectively, showed genotype-specific substitutions that distinguished the four HBoV genotypes. As the first whole-genome sequence analysis of HBoV in South Korea, this information will provide a valuable reference for the detection of recombination, tracking of epidemics and development of diagnosis methods for HBoV.

Sixteen strains of leptospires were isolated from surface water (14 in England and 2 in Italy) and were classified. They were all saprophytic, and nine of them belonged to known serovars: the others were found to represent new serovars within already known serogroups.

In the summer of 1940 an outbreak of paratyphoid fever occurred in Kettering and in the districts surrounding it. The total number of cases was 222. Most of them were mild, and the period of vague symptoms before a doctor was called in was in some as long as three weeks to a month. A few cases were more severe, and one or two at the beginning showed toxic symptoms which led to a diagnosis of meningitis. There was one death. The centre of the epidemic was in Kettering, but the surrounding districts were also affected. The population of this area in peace time is about 133,000: it has been somewhat increased by the influx of evacuees. The age and sex distributions are shown in Table 1.

The incidence was greater in women and children than in adult males. Fig. 1 shows in graphic form the number of notifications week by week. In a few instances the agglutination test of the patient's serum was the only examination made but in the majority Bact, paratyphosum B was isolated either from the blood, faeces or urine. The methods used in isolating the infecting organisms will be described in a separate paper. Many of the cases which were excreting small numbers of paratyphoid bacilli for only a short period were detected only by the use of selective ‘enrichment.’ media, and the experience gained in the epidemic showed that a negative result based only on the use of a comparatively non-selective medium such as McConkey agar is of little value and may be dangerously misleading. Most of the specimens were examined at Leicester Emergency Public Health Laboratory, but a few, especially at the beginning, were sent to private laboratories.

Salmonella senftenberg was isolated from 168 patients and staff of a general hospital whereas it was isolated from only seven other sources (four of which were unquestionably associated with the hospital) in the surrounding area during the same period. It was isolated in the hospital in 19 of the 48 months of the period. Two clear-cut episodes were recognized against a background of sporadic isolation. Four-fifths of the patients and staff excreting the organism had no symptoms. Only two are known to have been severely ill, though in some patients very ill for other reasons life may have been shortened a little.

The original source of the organism, whether from the farm or from raw materials such as meat or poultry, was not found.

Japanese weather data for areas that produced Campylobacter spp.-positive chicken products were compared with those for areas producing negative samples. Regarding samples produced during the period of rising temperature (spring and summer), the mean weekly air temperatures for Campylobacter-positive samples were higher than those for negative samples for the period of the week in which the samples were purchased (18·7°C vs. 13·1°C, P=0·006) to a 12-week lag (12 weeks before purchasing samples; 7·9°C vs. 3·4°C, P=0·009). Significant differences in weekly mean minimum humidity and sunshine duration per day were also observed for 1- and 2-week lag periods. We postulated that the high air temperature, high humidity and short duration of sunshine for the chicken-rearing period increased Campylobacter colonization in chickens during the period of rising temperature. Consequently, the number of Campylobacter-contaminated chicken products on the market in Japan may fluctuate because of the climatic conditions to which reared chickens are exposed.

Three sets of experiments were carried out on undergraduate medical students at Oxford, Cambridge and Liverpool during the years 1941–4 in order to supplement the information obtained previously (Downie et al. 1941) on the comparative antitoxin response of those given active immunization alone (Group A) and those given combined active and passive immunization (Group A+P). A summary of each of the experiments has already been given in the text, so that it is unnecessary here to do more than recapitulate briefly the main results.

1. The first experiment showed that in Group A the antitoxin response was not appreciably greater in students receiving doses of 0·3 and 0·3–0·5 ml. of A.P.T. at 4 weeks’ interval than in those receiving doses of only 0·1 and 0·3 ml. In Group A + P no difference was noticed in the antitoxin content of the serum 6–8 weeks after the second injection of A.P.T., but 10–12 weeks after the second injection there was a difference in favour of the students receiving the larger doses of A.P.T., though it was below the conventional level of statistical significance.

2. The second experiment showed that when the doses of A.P.T. were spaced by 2 instead of by 4 weeks the antitoxin response was much less in both the A and the A + P groups, though the difference was less in the latter group, particularly when the measurements were made 10–12 weeks after the second inoculation of A.P.T.

3. The third experiment showed that a dose of 5000 units of diphtheria antiserum given at the time of the first injection of A.P.T. inhibited antitoxin production to a greater extent than a dose of 400–500 units, though the difference was much less when the measurements were made at 12 weeks after the second inoculation than at 4 weeks.

A compilation of the results obtained during 1940–2 in groups of students receiving active and those receiving active plus passive immunization shows that the antitoxin production in the first group (Group A) was much higher than in the second group (Group A + P) 6–8 weeks after the second injection of A.P.T., but that 10–12 weeks after the second inoculation the difference, though still significant, was considerably less. The final Schick-test results at 10–12 weeks gave a Schick-conversion rate of 98.0% in Group A and of 90.9% in Group A + P.

A review of the results obtained during the years 1939–44 on about 450 students at Oxford, Sheffield and Liverpool leads to the conclusion that the effect of giving diphtheria antiserum at the time of the first injection of A.P.T. is to cause a delay and some degree of inhibition in the antitoxin response of the subject. The larger the amount of antiserum given, the greater is this effect. With a dose of 500 units, though the delay in antitoxin formation is very obvious 4 weeks after the second injection of A.P.T., the final degree of immunity attained, as judged by the antitoxin concentration of the blood serum and by the Schick-conversion rate, is not greatly inferior to that resulting from active immunization alone; and even with a dose of 5000 units, the Schick-conversion rate reaches 81 % 12 weeks after the second injection of A.P.T. It is clear, therefore, that the antiserum, even when given in a dose as large as 5000 units, does not neutralize more than a small part of the antigenic activity of the first dose of A.P.T. Its main effect is apparently to diminish the rate of sensitization of the tissues, so that when a second dose of A.P.T. is given 4 weeks later, the rise in the antitoxin content of the blood serum is considerably delayed. Our experiments suggest that by increasing the size of the first dose of A.P.T., some of this delay may be avoided.

The partial neutralization of the first dose of A.P.T. will result in a decrease in the total antigenic stimulus and a delay in the time at which ït comes into operation. It is suggested that, provided the tissues have not been previously sensitized to diphtheria toxin, the result may be that the two doses will act virtually as a single dose. Such an explanation, however, must remain unproven till further observations have been made (see p. 35).

The practical value of combined active and passive immunization, especially when joined with temporary segregation of healthy carriers, in combating outbreaks of diphtheria in schools and other institutions for children has been clearly shown by Fulton, Taylor, Wells & Wilson (1941). Our present experiments lead us to suggest that, when applying the method in practice, it would be wise to give an initial dose of 0·5 ml. of A.P.T., together with 500 units of diphtheria antiserum injected at a different site, followed 6 weeks later by a second dose of 0.5 ml. A.P.T. It is probable that children treated in this way will develop approximately the same ultimate degree of immunity as those actively immunized with doses of 0·3 and 0·5 ml. of A.P.T. at 4 weeks’ interval.

We should like to express our thanks to Prof. A. D. Gardner and Prof. H. R. Dean for permitting observations to be made on the students in the pathology classes at Oxford and Cambridge; and to the students themselves at Oxford, Cambridge and Liverpool, for their ready co-operation in the inquiry.

Twenty-nine strains of penicillinase-producing Neisseria gonorrhoeae (PPNG) and 30 non-penicillinase-producing strains, all isolated in the Gambia, were characterized in terms of their plasmid content, auxotype and protein-I serovar. Sixty-two per cent of the PPNG strains contained the 3·2 MDa penicillinasecoding plasmid, and 38% had the 4·4 MDa plasmid. All the PPNG strains contained the 2·6 MDa cryptic plasmid but lacked the 24·4 MDa conjugative plasmid. In contrast, 46·7% of the non-PPNG strains harboured only the cryptic plasmid while 16·7% contained both the cryptic and conjugative plasmids. Seventeen per cent of the non-PPNG strains contained the conjugative plasmid only and 20% lacked plasmids.

The PPNG and non-PPNG strains also differed in terms of their protein-I serovar. Eighty-six per cent of the PPNG strains belonged to serogroup 1A, whereas the majority (60%) of non-PPNG strains belonged to serogroup IB. There was no significant difference in the auxotypes of the PPNG and non-PPNG strains, with both groups consisting predominantly of prototrophic and prolinerequiring strains, with a minority of strains requiring arginine. When the 59 strains were each characterized in terms of their combined plasmid profile, auxotype and serovar, 39 different combinations were noted, which indicates the heterogeneous nature of the gonococcal population found in the Gambia.

To clarify the determinants of vaccine trial power for non-typable Haemophilus influenzae, we constructed stochastic SIS models of infection transmission in small units (e.g. day-care centres) to calculate the equilibrium distribution of the number infected. We investigated how unit size, contact rate (modelled as a function of the unit size), external force of infection and infection duration affected the statistical power for detection of vaccine effects on susceptibility or infectiousness. Given a frequency-dependent contact rate, the prevalence, proportion of infections generated internally and the power to detect vaccine effects each increased slightly with unit size. Under a density-dependent model, unit size had much stronger effects. To maximize information allowing inference from vaccine trials, contact functions should be empirically evaluated by studying units of differing size and molecular methods should be used to help distinguish internal vs. external transmission.

In 1929, for the third time in the present century, cerebrospinal fever occurred in Glasgow in epidemic form. The first epidemic, which was by far the most severe, was in 1906–8, the total number of cases recorded being 1363. Descriptions of the events of these years were given by Dr A. K. Chalmers (1906) in the Annual Reports of the Medical Officer of Health of Glasgow for 1906 and 1907, and also in a paper read before the Epidemiological Society. In this outbreak the fatality rate of cases treated in hospital was given as 74·8 per cent. by Currie and Macgregor (1908). The total number of cases admitted to hospital was 910. The incidence of the disease was highest during the months of January to May of 1907, and there was a slight recrudescence in the same months of the following year. The characteristics of the epidemic form of cerebro-spinal fever were present in so far as there occurred several instances of multiple infection in the same house, and a number of cases showed the exanthem peculiar to the disease.

After the introduction of the 13-valent pneumococcal conjugate vaccine (PCV13), serotype replacement has occurred in Japan, and serotype 24 has become the most common serotype in paediatric invasive pneumococcal disease (IPD). To understand the characteristics of serotype 24-IPD in Japanese children in the post-PCV13 era, we conducted a retrospective study in children aged ≤15 years from 2010 to 2020 using a database of paediatric IPD surveillance in Chiba prefecture, Japan. We identified a total of 357 IPD cases and collected clinical information on 225 cases (24: 32 cases, non-24: 193 cases). Compared with the non-serotype 24-IPD, serotype 24-IPD was independently related to be <2 years of age [odds ratio (OR) 3.91, 95% confidence interval (CI) 1.47–10.44; P = 0.0064] and bacteremia (OR 2.28, 95% CI 1.01–5.13; P = 0.0475), as a result of the multivariate regression analysis. We also conducted a bacterial analysis, and the isolates of serotype 24-IPD had tendencies of PCG-susceptible (24: 100.0%, non-24: 61.3%; P < 0.0001) and macrolide-resistance (24: 100.0%, non-24: 87.3%; P = 0.0490). Their multilocus sequence typing was mostly ST2572 and the variants, which were unique to Japan. This tendency might have been a result of the progress made in the Japanese PCV13 immunisation programme.

The incidence of scarlet fever has increased dramatically in recent years in Chongqing, China, but there has no effective method to forecast it. This study aimed to develop a forecasting model of the incidence of scarlet fever using a seasonal autoregressive integrated moving average (SARIMA) model. Monthly scarlet fever data between 2011 and 2019 in Chongqing, China were retrieved from the Notifiable Infectious Disease Surveillance System. From 2011 to 2019, a total of 5073 scarlet fever cases were reported in Chongqing, the male-to-female ratio was 1.44:1, children aged 3–9 years old accounted for 81.86% of the cases, while 42.70 and 42.58% of the reported cases were students and kindergarten children, respectively. The data from 2011 to 2018 were used to fit a SARIMA model and data in 2019 were used to validate the model. The normalised Bayesian information criterion (BIC), the coefficient of determination (R2) and the root mean squared error (RMSE) were used to evaluate the goodness-of-fit of the fitted model. The optimal SARIMA model was identified as (3, 1, 3) (3, 1, 0)12. The RMSE and mean absolute per cent error (MAPE) were used to assess the accuracy of the model. The RMSE and MAPE of the predicted values were 19.40 and 0.25 respectively, indicating that the predicted values matched the observed values reasonably well. Taken together, the SARIMA model could be employed to forecast scarlet fever incidence trend, providing support for scarlet fever control and prevention.

The prevalence of TT virus (TTV) and GB virus-C/hepatitis G virus (GBV-C/HGV) infection and the association with raised liver function tests in 546 Taiwanese with negative HBsAg, anti-HCV and HCV RNA was elucidated. They were tested for serum alanine aminotransferase (ALT), GBV-C/HGV RNA, anti-envelope protein 2 antibody (anti-E2) and TTV DNA. Direct sequencing and phylogenetic analyses were performed on 58 isolates for TTV genotype determination. The prevalence of TTV DNA, GBV-C/HGV RNA, anti-E2 and over all GBV-C/HGV exposure was 24.9, 3.4, 8.2 and 11.1%, respectively. Using uni- and multi-variate analyses, male gender and TTV viremia were associated significantly with raised ALT values. Sixty-nine percent of TTV isolates were deduced to be TTV genotype 1 and they had significantly lower mean age than genotype non-1 isolates. In the population, raised ALT may be related to male gender and be attributable to TTV infection but not to GBV-C/HGV among individuals with no evidence of current HBV and HCV infection. TTV genotype 1 is the most prevalent genotype and associated with younger age.

Reports have suggested that isoniazid treatment may be associated with poor concentration and subtle reduction in memory. This study examines attentional function and processing speed in a group of 25 adolescents who received isoniazid prophylaxis for at least 6 months. As adolescents often face major educational assessment milestones, such cognitive side effects may have important implications. Participants were assessed before treatment, 1 month into treatment and at least 1 week after treatment cessation. Measures included the Paced Auditory Serial Addition Test and subtests of the appropriate Wechsler scale sensitive to attention and speed of information processing. Isoniazid does not appear to cause significant adverse effects on attentional function in adolescents.

We sought to estimate mortality and associated factors in HIV-hepatitis co-infected individuals in Michigan using a retrospective cohort study. For the study period of 1 January 2006 to 31 December 2009, all HIV-infected individuals were matched to hepatitis B and C cases. In the final Cox proportional hazards regression model, individuals of other [hazard ratio (HR) 2·2, 95% confidence interval (CI) 1·4–3·2] and black (HR 1·3, 95% CI 1·1–1·6) race had decreased survival compared to white race. Similarly, injecting drug users (IDUs) (HR 2·1, 95% CI 1·6–2·6), men who have sex with men (MSM)/IDUs (HR 1·5, 95% CI 1·1–2·2), individuals with undetermined risk (HR 1·5, 95% CI 1·2–1·9) and heterosexual practices (HR 1·4, 95% CI 1·1–1·8) had decreased survival compared to MSM. Additionally, an interaction was found between current HIV status and co-infection. Mortality in HIV-hepatitis co-infected individuals remains a continuing problem. Our study can help in planning interventions to reduce mortality in HIV-infected individuals.

Gatherings where people are eating and drinking can increase the risk of getting and spreading SARS-CoV-2 among people who are not fully vaccinated; prevention strategies like wearing masks and physical distancing continue to be important for some groups. We conducted an online survey to characterise fall/winter 2020–2021 holiday gatherings, decisions to attend and prevention strategies employed during and before gatherings. We determined associations between practicing prevention strategies, demographics and COVID-19 experience. Among 502 respondents, one-third attended in person holiday gatherings; 73% wore masks and 84% practiced physical distancing, but less did so always (29% and 23%, respectively). Younger adults were 44% more likely to attend gatherings than adults ≥35 years. Younger adults (adjusted prevalence ratio (aPR) 1.53, 95% CI 1.19–1.97), persons who did not experience COVID-19 themselves or have relatives/close friends experience severe COVID-19 (aPR 1.56, 95% CI 1.18–2.07), and non-Hispanic White persons (aPR 1.57, 95% CI 1.13–2.18) were more likely to not always wear masks in public during the 2 weeks before gatherings. Public health messaging emphasizing consistent application of COVID-19 prevention strategies is important to slow the spread of COVID-19.

A technique involving the suppression of normal intestinal flora with antibiotics, and the introduction of streptomycin-resistant coliforms was used for the study of infections in mice.

It was shown that Escherichia coli, both the enteropathogenic and normal faecal strains, tend to colonize the upper intestinal tract as well as the lower region. An oral dose of ten or less cells could produce a chronic infection. Infections were asymptomatic even with an initial dose of 109 bacteria. There was no indication of growth advantages for enteropathogenic coliforms in competition with normal.