1. An outbreak of typhoid fever in a Royal Air Force camp in the Middle East is discussed.

2. A total of 110 cases occurred of which 105 are analysed. The case-fatality rate was 10%.

3. Of the 105 cases 59% gave a positive blood culture. The percentages of diagnostic isolations from stools and urine were small.

4. Clearance tests of stools and urine showed that 8.4% of patients excreted Salm. typhi during convalescence.

5. Leucocyte counts during the first 2 weeks of the illness showed that only 30% of the patients had a count below 5000 per cu.mm.; 62% of these low figures were encountered in severe cases.

6. Autopsies on seven fatal cases showed considerable variability in the macroscopic appearance of the intestinal lesions.

7. Serological investigation confirmed that higher percentages of cases with low titres of O agglutinin were found in the severe and mild clinical groups, and that most O titres in the moderately severe cases exceeded 1:200.

8. Of the patients 52% showed Vi titres exceeding 1:20 during convalescence.

9. The significance of various findings is discussed.

To know the types of meningococcal strains in Spain, we serotyped and subtyped 743 Neisseria meningitidis isolates recovered between 1990 and 1992 from patients. A great number of serogroup B, serogroup C and non-groupable meningoccoci reacted with the serotyping reagents while many serogroup C and non-groupable isolates did not react with the serosubtyping reagents (78·2% and 54·8 % respectively); only 8·9 % of serogroup B meningococci were non-subtypeable (NST). Distribution of serotypes was similar in serogroup C and in non-groupable strains. Isolates showed great variability in antigenic phenotypes (71 in serogroup B, 20 in serogroup C and 25 in non-groupable meningococci). The most frequent antigenic combinations were 4:P1. 15 (39·8%) in serogroup B, 2b:NST (55·8%) in serogroup C and 2b:NST (35·6%) in non-groupable meningococci.

About 800 foodborne disease outbreaks are reported in the United States annually. Few are associated with food recalls. We compared 226 outbreaks associated with food recalls with those not associated with recalls during 2006–2016. Recall-associated outbreaks had, on average, more illnesses per outbreak and higher proportions of hospitalisations and deaths than non-recall-associated outbreaks. The top confirmed aetiology for recall-associated outbreaks was Salmonella. Pasteurised and unpasteurised dairy products, beef and molluscs were the most frequently implicated foods. The most common pathogen−food pairs for outbreaks with recalls were Escherichia coli-beef and norovirus-molluscs; the top pairs for non-recall-associated outbreaks were scombrotoxin-fish and ciguatoxin-fish. For outbreaks with recalls, 48% of the recalls occurred after the outbreak, 27% during the outbreak, 3% before the outbreak, and 22% were inconclusive or had unknown recall timing. Fifty per cent of recall-associated outbreaks were multistate, compared with 2% of non-recall-associated outbreaks. The differences between recall-associated outbreaks and non-recall-associated outbreaks help define the types of outbreaks and food vehicles that are likely to have a recall. Improved outbreak vehicle identification and traceability of rarely recalled foods could lead to more recalls of these products, resulting in fewer illnesses and deaths.

The increasing use of intensive cytotoxic chemotherapy for patients with solid tumors enhances the risk of opportunistic infection to levels formerly seen only in patients with acute leukaemia, and prevention of infection is a major concern. A relatively simple regimen of isolation, topical antisepsis, and orally administered non-absorbable antibiltics was stuidied in 18 patients. Sixteen of 21 studies were performed using portable laminar ait flow apparatus and five with isolation only. All patients became severly neutropenic but there were no major infections. Microbiological results showed effective decontamination of the skin, which was maintained without recolonization or acquisition of new organisms. The ears, nose and throat were effectively decontaminated only when the regimen was intensified. Colonization with Pseudomonas aeruginosa, a major pathogen in compromised hosts, did not occur. The propective regimen is less expensive than regimens previously desribed, is acceptable to patients, and requires no modification of existing hospital rooms. It merits further evaluation in patients with common cancers who receive intensive cytotoxic drug therapy.

Hepatitis E virus (HEV) infection is a major cause of acute hepatitis worldwide. This infection causes major water-borne outbreaks in low- and middle-income countries, whilst in industrialised countries this infection is zoonotic. These differences in epidemiology are related to different HEV genotypes. HEV genotype 3 is a zoonotic infection, whilst genotype 2 causes large outbreaks. This study determined the seroprevalence of HEV in blood donors from the Western Cape. Anti-hepatitis A virus (anti-HAV) antibody was detected in 184/300 (61%) donors. Antibody to HEV (anti-HEV) was detected in 78 of 300 donors (26%). It was highest in mixed race donors (62/100), followed by white donors (23/100) and lowest in black donors (19/100) P = 0.019. Since it is thought that genotypes 1 and 2 predominate both viruses would be acquired by the oro-faecal route, it is surprising that HEV seroprevalence does not mirror that of HAV. We postulate that this may reflect differences in socio-economic status and consumption of dietary meat. So the marked divergence between HEV and HAV seroprevalence may be the result of different routes of transmission. Further data are needed to explore the risk factors associated with HEV infection.

All the four types of acid-fast bacilli used in this investigation have proved virulent for the golden hamster. Of the four types the bovine is the most virulent for the species and, after subcutaneous inoculation, gives rise to severe generalized progressive tuberculosis, the lesions containing enormous numbers of tubercle bacilli. The human type is also highly virulent for the hamster and produces general progressive tuberculosis closely resembling that set up by bovine bacilli. Caseation of the lesions in the organs was, however, less extensive in the human than in the bovine infections but there was little difference in this respect between the glandular lesions of the two infections, and multiplication of bacilli was as profuse in one as in the other. Avian bacilli can readily multiply in the tissues of the hamster and cause death, but appear unable to give rise to macroscopic tuberculous lesions. Only one hamster was injected with avian bacilli and the result of this experiment is not in accord with those of Balfour-Jones already quoted. The vole bacillus is less virulent for the hamster than either the bovine or the human type of bacillus. Of the two hamsters injected with this type of bacillus one was killed 152 days later, its general condition then being good and its body showing plenty of subcutaneous fat. Nevertheless the organs were found to contain tuberculosis-like lesions, numerous in the spleen and liver, and the lymphatic glands generally were enlarged. The remaining hamster died 188 days after inoculation and showed generalized disease very similar to that in the last hamster. The glandular and visceral lesions of both hamsters contained very numerous acid-fast bacilli but, in striking contrast to those produced by bovine and human bacilli, showed no evidence of caseation.

Acid-fast bacilli were present in the faeces of all the hamsters; they were numerous in those of hamsters 3, 4, 5 and 2 and relatively sparse in those of hamsters 1 and 6.

In recent years, outbreaks of hand–foot–mouth disease (HFMD) in China, Singapore and other Western Pacific Region, involving millions of children, have become a big threat to public health. This study aimed to quantitatively assess all qualified studies and identify the risk factors for HFMD death. A systematic search of the databases PubMed, Medline, Embase and the Cochrane Library was performed. Study heterogeneity and publication bias were estimated. Seven case–control studies involving 1641 participants (634 died and 1007 survived) were included in the meta-analysis. Human enterovirus 71 infection, male, age ⩽3 years, vomiting, cyanosis, convulsion, duration of fever ⩾3 days, atypical rashes and abdominal distention were not significantly related to HFMD death (P ⩽ 0.05). Lethargy (odds ratio (OR) = 6.62; 95% CI 3.61–12.14; I2 = 0%; P < 0.0001), pneumonoedema/pneumorrhagia (OR = 4.09; 95% CI 2.44–6.87; I2 = 0%; P < 0.0001), seizures (OR = 6.85; 95% CI 2.37–19.74; I2 = 0%; P = 0.0004), dyspnoea (OR = 8.24; 95% CI 2.05–33.19; I2 = 83%; P = 0.003) and coma (OR = 3.76; 95% CI 1.85–7.67; I2 = 0%; P = 0.0003) were significantly associated with HFMD death, which were risk factors for HFMD death.

We report on the first recorded outbreak of cholera in Namibia. From December 2006 to February 2007, more than 250 cases of cholera were reported from the Omusati and Kunene provinces of Namibia. However, only nine bacterial isolates were obtainable for analysis. Isolates were all identified as Vibrio cholerae O1 serotype Inaba biotype El Tor. All isolates were susceptible to ampicillin, augmentin, chloramphenicol, nalidixic acid, ciprofloxacin, tetracycline, kanamycin, imipenem, ceftriaxone and ceftazidime; and they all showed resistance to trimethoprim, sulfamethoxazole and streptomycin. Pulsed-field gel electrophoresis analysis of bacteria incorporating either SfiI or NotI digestion revealed an identical fingerprint pattern for all isolates. These data together with results indicating identical antimicrobial susceptibility profiles for all isolates determined that the outbreak was caused by a single strain of V. cholerae.

Hand, foot and mouth disease (HFMD) is an acute contagious condition caused by a spectrum of human enteroviruses. HFMD reinfection is common in the absence of cross-protection from other virus subtypes. This study focused on reinfection in children in Anhui province, China between 2008 and 2013 using surveillance system data. We classified 8960 cases as reinfected, corresponding to a rate of 2·02%. The reinfection rate was higher in boys than in girls [odds ratio (OR) 1·27, 95% confidence interval (CI) 1·21–1·32, P < 0·001], children aged < 3 years (OR 3·82, 95% CI 3·58–4·07, P < 0·001), and children living in rural areas (OR 1·09, 95% CI 1·04–1·14, P = 0·001). The reinfection rate in children who were originally infected with non-enterovirus A71 (non-EVA71) enteroviruses was higher than those infected with EVA71 (OR 1·36, 95% CI 1·02–1·80, P = 0·034). Influential factors of reinfection rate included annual incidence (β coefficient = 0·715, P = 0·002) and the proportion of EVA71 in patients with mild HFMD (β coefficient = −0·509, P = 0·018). These results demonstrate that boys aged <3 years, especially those in rural areas or regions with a lower EVA71 proportion are more prone to reinfection, and specific health education programmes should be developed to protect these susceptible populations.

Contact precautions are a traditional strategy to prevent transmission of methicillin-resistant Staphylococcus aureus (MRSA). Chlorhexidine bathing is increasingly used to decrease MRSA burden and transmission in intensive care units (ICUs). We sought to evaluate a hospital policy change from routine contact precautions for MRSA compared with universal chlorhexidine bathing, without contact precautions. We measured new MRSA acquisition in ICU patients and surveyed for MRSA environmental contamination in common areas and non-MRSA patient rooms before and after the policy change. During the baseline and chlorhexidine bathing periods, the number of patients (453 vs. 417), ICU days (1999 vs. 1703) and MRSA days/1000 ICU days (109 vs. 102) were similar. MRSA acquisition (2/453 vs. 2/457, P = 0·93) and environmental MRSA contamination (9/474 vs. 7/500, P = 0·53) were not significantly different between time periods. There were 58% fewer contact precaution days in the ICU during the chlorhexidine period (241/1993 vs. 102/1730, P < 0·01). We found no evidence that discontinuation of contact precautions for patients with MRSA in conjunction with adoption of daily chlorhexidine bathing in ICUs is associated with increased MRSA acquisition among ICU patients or increased MRSA contamination of ICU fomites. Although underpowered, our findings suggest this strategy, which has the potential to reduce costs and improve patient safety, should be assessed in similar but larger studies.

A trial of protective efficacy which compared medium–titre Edmonston-Zagreb (EZ) measles vaccine (104.6 p.f.u.) from the age of 4 months with the standard Schwarz (SW) measles vaccine given from the age of 9 months was started in an urban community in Guinea-Bissau in 1985. Because trials of high–titre measles vaccine have found increased mortality among female recipients, we examined whether EZ medium–titre vaccine was associated with any long-term impact on mortality, suppression of T–cells, or growth. The mortality rate ratio over 5 years of follow–up was 1.12 for EZ children compared with children in the standard group (P = 0.63). Seventy–five percent of the children still residing in the area at 5 years of age took part in an immunological and anthropometric examination. There was no difference in T–cell subsets between the two groups. There was no difference in mid–upper–arm circumference, but EZ children were significantly shorter than the children in the standard group. In conclusion, medium–titre EZ was not associated with reduced survival or persistent immunosuppression.

Autopsies on all the guinea-pigs kept for as long as 20 months failed to reveal any trace of tuberculosis, although the grass grazed by the animals was proved by subcutaneous inoculation to bear virulent organisms, which might have been expected to reach the alimentary tract in considerable numbers, at least in the earlier experiments.

By repeated infection of a grazing area it has been possible to induce tuberculosis in guinea-pigs grazed in the open and in those fed indoors on cut grass. In the 1932 experiment a total of thirty guinea-pigs were allowed access to plots of grass which had been infected, one, four and eight days previously and all failed to become infected. The combined experiments (1932 and 1933) suggest that under some weather conditions, animals, although admitted to pasture within a very short time of its infection may escape infection with tuberculosis, but that repeated infection of pasture results in a high incidence of disease in animals grazing on it.

We compared the use of recto-anal mucosal swab (RAMS) culture and faecal culture for the detection of E. coli O157 in a mob of Merino sheep. Fifty Merino wethers and maiden ewes housed in indoor pens were sampled on five occasions. We detected E coli O157 in 32% (16/50) of sheep, with weekly prevalence ranging from 4% (2/50) to 16% (8/50). Overall, 12·5% (2/16) were detected by RAMS culture only, and 37·5% (6/16) were detected by faecal culture only. The level of agreement between the two sampling methods was moderate [kappa statistic = 0·583, 95% confidence interval (CI) 0·460–0·707]. The relative sensitivities of RAMS and faecal culture were 67% (95% CI 41–86) and 57% (95% CI 34–77), respectively. We identified four super-shedding sheep using direct faecal culture. Although the majority of culture-positive sheep were detected at one sampling point only, 3/4 super-shedding sheep were culture-positive at two sampling points, and 1/4 was culture-positive at four sampling points. Persistent culture positivity may indicate sheep that could be considered ‘super-shedders' at some point. The use of immunomagnetic separation further improved the rate of detection of E. coli O157, which was isolated from 1/34 animals that were previously negative by enrichment culture alone. A significant difference between sampling weeks was detected for both faecal (P = 0·021) and RAMS (P = 0·006), with the prevalence at the mid-point of sampling (week 4) significantly (P < 0·05) higher than at the beginning or end of the study. Study conditions (penned sheep) might have been responsible for the high prevalence and the epidemic pattern of infection observed, and could serve as a future model for studies of E. coli O157 transmission, shedding and super-shedding in sheep.

1. A collection was made of organisms of the coli-aerogenes group; 100 from the human intestine, 50 from animals, and 50 from the soil. To these were applied the indol test, the methyl red and Voges-Proskauer tests, and Koser' citrate test. The citrate test was also applied to certain non-lactose fermenters.

2. 89·4 per cent. of 150 faecal organisms gave the combination of a failure to grow in citrate solution, the production of indol, an acid reaction with methyl red and a negative Voges-Proskauer reaction.

3. There is a probability that some faecal organisms have crept into the “soil” series, but the contamination is not heavy enough to make the results useless. The figures show that the citrate and indol test are both useful, the citrate being a little better. The methyl red and Voges-Proskauer reactions were not helpful.

4. In the bacteriological examination of water in Shanghai it is safe to take those organisms which can grow in citrate but do not produce indol as being non-faecal.

1. The main differences between intracerebral and intranasal infections in mice with virulent strains of Bordetella pertussis are in: (1) the responses to small in fecting doses (< 1 LD 50); (2) the action of antisera in controlling infection; (3) the action of toxin on brain and lung; and (4) the rates of increase of the viable count. The two infections can run concurrently in the same mouse without any demonstrable interference.

2. The terminal viable count in the lung and brain is c. 108 organisms.

3. In the brain there is no sublethal infection with virulent strains; probably even single organisms can grow up to the critical level and kill the mouse. In the lung sublethal infections are found in which the count rises to a figure below the critical level and then declines.

4. The action of ‘intranasal’ antiserum is to reduce a lethal infection to a sublethal one in the lung but there is no effect in the brain. ‘Intracerebral’ antisera cannot act until the blood-brain barrier becomes leaky, when they are able to reduce the viable count and eventually sterilize the brain. In the lung ‘intracerebral’ sera have no action against lethal infections but can control small infections (<I LD 50). The sublethal intranasal test measures this effect but it also measures the action of ‘intranasal’ sera and so cannot be used to distinguish the two types of sera and hence the two antigens.

Unlike for many other respiratory infections, the seasonality of pertussis is not well understood. While evidence of seasonal fluctuations in pertussis incidence has been noted in some countries, there have been conflicting findings including in the context of Australia. We investigated this issue by analysing the seasonality of pertussis notifications in Australia using monthly data from January 1991 to December 2016. Data were made available for all states and territories in Australia except for the Australian Capital Territory and were stratified into age groups. Using a time-series decomposition approach, we formulated a generalised additive model where seasonality is expressed using cosinor terms to estimate the amplitude and peak timing of pertussis notifications in Australia. We also compared these characteristics across different jurisdictions and age groups. We found evidence that pertussis notifications exhibit seasonality, with peaks observed during the spring and summer months (November–January) in Australia and across different states and territories. During peak months, notifications are expected to increase by about 15% compared with the yearly average. Peak notifications for children <5 years occurred 1–2 months later than the general population, which provides support to the theory that older household members remain an important source of pertussis infection for younger children. In addition, our results provide a more comprehensive spatial picture of seasonality in Australia, a feature lacking in previous studies. Finally, our findings suggest that seasonal forcing may be useful to consider in future population transmission models of pertussis.

A regimen of oral non-absorbable prophylactic antibiotics (kanamycin–vanco–mycin–nystatin) was given to nine severely neutropaenic leukaemic patients on cytotoxic therapy (11 courses), in conjunction with isolation procedures. An appreciable decrease in faecal organisms, especially anaerobes, was apparent after 48 h of commencing the course, and most bacteria had disappeared from the stool after five days. There were three episodes of septicaemia, all with enteric organisms, whilst on these antibiotics; one proved fatal. The emergence of resistance to aminoglycosides in faecal flora, notably Klebsiella, in 6/11 courses constituted a major problem in the use of such prophylaxis.

The prevalence of the different types of coli–aerogenes bacteria has been determined in various soils collected from widely separated locations in the United Kingdom and in Denmark. Of the soils examined, 27% contained no coli–aerogenes organisms in 15 g. of soil tested. The number of these organisms in the positive soils was very low; only 11% had confirmed counts greater than 100 organisms/g. and 33% less than 1 organism/g.

The most prevalent organism isolated was Bacterium coli type I, whatever the location or vegetation type of the soil; intermediate type I, Bact. aerogenes type I and Bact. coli type II were the only other organisms of numerical importance. The annual application of large amounts of either farmyard or inorganic manures produces no permanently large population of coli-aerogenes organisms in soils.

Presumptive tests in MacConkey broth were unreliable, since only 6 % of the positive tubes from hill and moorland soils and 28 % from arable soils were confirmed as containing coli-aerogenes bacteria. Such discrepancies are considered to be partly due to coliform bacteria with weak lactose-fermenting properties.

It is considered that there is now sufficient experimental evidence to discredit statements that soil is the natural habitat of Bact. aerogenes or intermediate types of coli-aerogenes organism.

Rotaviruses present in products of wastewater treatment were assayed in MA 104 cells by indirect immunofluorescence. Levels in settled sewage, activated sludge and effluent were greater than 103 per litre in March and April but virus was not detected during later months. This pattern correlated with the decline in laboratory reports of human rotavirus infection.

The multiplication rate of blue-tongue virus in suckling and adult mouse brains has been determined. The first cycle of virus multiplication appears to take 8–12 hr. both in fully susceptible sucklings and in adults which suffer an inapparent infection with this virus.

Antigens suitable for complement-fixation tests have been made from suckling mouse brains and from eggs infected with blue-tongue virus.

A potent immune serum has been obtained from mice immunized by repeated intraperitoneal injections of blue-tongue virus in suckling mouse brain.

Attempts, with negative results, have been made to demonstrate interference with virus multiplication by virus from eggs incubated at 38·5° C. and by virus from adult mouse brains.

We are grateful to Dr R. Alexander for his helpful and critical interest in this work and to Mr G. S. Turner and Dr G. Selzer for their able and willing assistance.

The Virus Research Unit is financed by the South African Council for Scientific and Industrial Research and by grants from the Nkana-Kitwe and Chingola Poliomyelitis Research Funds.