There are very few data on the prevalence of coccidian enteric parasites among low-income adults hospitalized in Chennai, India. Stool samples from 200 patients were screened for selected parasites, enteric bacterial pathogens, and other protozoa over a 3-month period. The study identified 42 (21%) Cryptosporidium, 36 (18%) V. cholerae, 17 (9%) Salmonellla, 12 (6%) Isospora, six (3%) helminths, five (3%) Shigella, one (1%) Cyclospora, one (1%) other protozoan, and 0% V. parahaemolyticus cases. Co-infection was present in 21 patients. Cryptosporidium was detected in 17 (81%) of co-infected patients. Our findings highlighted the relatively high proportion of patients in this population with Cryptosporidium and Isospora and suggest that further study be undertaken to determine the utility of broader use of diagnostic testing for coccidian parasites in India. Detection may be beneficial because isosporiasis is treatable and both Isospora and Cryptosporidium are important pathogens in AIDS patients.

In a previous paper (Maddock, 1934), it has been shown that healthy calves may be infected with bovine tubercle bacilli when grazed upon pasture infected at intervals with emulsions of the virulent organisms. These infections were designedly heavy, and it was felt that this orientating experiment should be followed by one in which pasture infection was secured in a way more closely approximating to the natural.

Sera from 218 of 1574 (14%) small mammals collected in the Yukon Territory between 14 May and 13 August 1972 neutralized a Yukon strain of California encephalitis virus (snowshoe-hare subtype). These included 133 of 319 (42%) snowshoe hares (Lepus americanus), 84 of 1243 (7%) ground squirrels (Citellus undulatus) and 1 of 12 (8%) tree squirrels (Tamiasciurus hudsonicus). California encephalitis virus (snow-shoe hare subtype) was isolated from four pools of unengorged Aedes communis mosquitoes collected near Whitehorse (61° N., 135° W.) and on one occasion each from pools of the same species collected at Hunker Creek (64° N., 138° W.) and at mile 125, Dempster Highway (66° N., 138° W.) during July 1972. Replication of a Yukon strain of California encephalitis virus was observed in wild-caught Culiseta inornata and Aedes canadensis mosquitoes after intrathoracic injection and holding at temperatures of 80°, 50° and 40° F.

The World Health Organization African region recorded its first laboratory-confirmed coronavirus disease-2019 (COVID-19) cases on 25 February 2020. Two months later, all the 47 countries of the region were affected. The first anniversary of the pandemic occurred in a changed context with the emergence of new variants of concern (VOC) and growing COVID-19 fatigue. This study describes the epidemiological trajectory of COVID-19 in the region, summarises public health and social measures (PHSM) implemented and discusses their impact on the pandemic trajectory. As of 24 February 2021, the African region accounted for 2.5% of cases and 2.9% of deaths reported globally. Of the 13 countries that submitted detailed line listing of cases, the proportion of cases with at least one co-morbid condition was estimated at 3.3% of all cases. Hypertension, diabetes and human immunodeficiency virus (HIV) infection were the most common comorbid conditions, accounting for 11.1%, 7.1% and 5.0% of cases with comorbidities, respectively. Overall, the case fatality ratio (CFR) in patients with comorbid conditions was higher than in patients without comorbid conditions: 5.5% vs. 1.0% (P < 0.0001). Countries started to implement lockdown measures in early March 2020. This contributed to slow the spread of the pandemic at the early stage while the gradual ease of lockdowns from 20 April 2020 resulted in an upsurge. The second wave of the pandemic, which started in November 2020, coincided with the emergence of the new variants of concern. Only 0.08% of the population from six countries received at least one dose of the COVID-19 vaccine. It is critical to not only learn from the past 12 months to improve the effectiveness of the current response but also to start preparing the health systems for subsequent waves of the current pandemic and future pandemics.

An outbreak of rubella in April 1996 involved four male British soldiers deployed to Bosnia–Herzegovina. All were helicopter ground crew who were members of the same unit and who periodically travelled to and worked at forward air refuelling stations in Bosnia. There was a potential for spread of the infection to adjacent British units, to troops of other nations in the peacekeeping force, and also to the local civilian population. The British force included 620 female personnel, some of whom may have been non-immune to rubella. One pregnant British servicewoman was repatriated to UK for her own protection. There was a potential health risk, including the possibility of congenital rubella syndrome, in the non-immune wives and partners of deployed male personnel, as a result of contact during the mid-tour home leave of the husbands or partners. The outbreak was monitored through a medical surveillance system known as ARRC 97, and was contained by prompt and rigorous control measures. This outbreak shows the importance of effective surveillance and of good microbiology laboratory support during military operations. The role of immunization against rubella during future military deployments is discussed.

The effects of posture and clothing on the effective radiating surface of the body are discussed. Some results obtained by Bohnenkamp and Pasquay by their electrical capacity method are criticised, and measurements made by the application of Simpson's rule are described.

The conclusion is reached that no serious error results from assuming that the effective radiating surface of the clothed subject, when in a normal standing posture, is of about the same area as that given by the Du Bois equation for skin area.

In two nude subjects, crouching in the most cramped position possible, the estimated radiating surface was reduced by 19 and 8 per cent, as compared with a standing posture.

In October 2019, public health surveillance systems in Scotland identified an increase in the number of reported infections of Shiga toxin-producing Escherichia coli (STEC) O26:H11 involving bloody diarrhoea. Ultimately, across the United Kingdom (UK) 32 cases of STEC O26:H11 stx1a were identified, with the median age of 27 years and 64% were male; six cases were hospitalised. Among food exposures there was an association with consuming pre-packed sandwiches purchased at outlets belonging to a national food chain franchise (food outlet A) [odds ratio (OR) = 183.89, P < 0.001]. The common ingredient identified as a component of the majority of the sandwiches sold at food outlet A was a mixed salad of Apollo and Iceberg lettuce and spinach leaves. Microbiological testing of food and environmental samples were negative for STEC O26:H11, although STEC O36:H19 was isolated from a mixed salad sample taken from premises owned by food outlet A. Contamination of fresh produce is often due to a transient event and detection of the aetiological agent in food that has a short-shelf life is challenging. Robust, statistically significant epidemiological analysis should be sufficient evidence to direct timely and targeted on-farm investigations. A shift in focus from testing the microbiological quality of the produce to investigating the processes and practices through the supply chain and sampling the farm environment is recommended.

Bacteriological surveys of beach pollution were made at a seaside resort before and after the installation of a new sewer outfall.

The presumptive coliform count on samples of sea water was found to be a satisfactory index of contamination, and showed good agreement with sanitary survey and with the results of float-test observations. The faecal coli count was in general constantly related to the results of the presumptive test, but there was some indication that coliform bacilli of the I.A.C. groups persisted or multiplied in the sand around the outfall.

The degree of contamination of the sea water at a given sampling point was shown to depend not only on its distance from the outfall but on various meteorological and tidal factors.

For bacteriological surveys of beach pollution, it is suggested that a large series of tests by a relatively simple technique is preferable to a more limited investigation by more complex methods.

The possibility of laying down bacteriological standards for bathing beaches is discussed. An upper permitted limit of the order of 1000 coliform organisms per 100 ml. would discriminate between areas on the beach investigated which were unsatisfactory by sanitary survey before and after the installation of the new sewerage scheme, and those parts of the beach which were apparently not subject to serious pollution with sewage.

I am greatly indebted to Lt.-Col. J. M. Linton Bogle, consulting engineer responsible for the sewerage scheme described, for his interest in and practical help with this investigation; to members of the staff of the local authority concerned for help with sampling, and to Dr A. F. Ollerenshaw and Mr A. Partridge, who were in local charge of the temporary laboratory where the presumptive tests were carried out, in 1950 and 1948 respectively.

Enterohaemorrhagic Escherichia coli O157 (O157) is infectious to humans, particularly children, at very low doses and causes not only haemorrhagic colitis but also other serious symptoms. To investigate an association between intestinal bacterial flora and resistance to such infections, we screened faecal samples for the presence of enteric bacteria that are able to suppress the growth of O157. Samples from 303 individuals, 35 children (aged [les ]6 years) and 268 adults (aged 20–59 years), were examined. Colonies with different appearances on sorbitol MacConkey agar medium were screened for the production of bacteriocins inhibitory for O157 in an overlay agar plate assay. O157-inhibiting strains were isolated from 52 individuals. The prevalence of these bacteria tended to rise with age, and was significantly higher among 40- to 59-year-old adults (23/101, 22·8%) than among children (3/35, 8·6%; P<0·05). To test the hypothesis that these bacteriocin-producing strains contribute to resistance against O157 in human adults, we examined faecal samples of 25 healthy O157 carriers. Inhibitory bacteria were more prevalent among the latter (9/25, 36·0%) than among age-matched subjects who did not carry O157 (49/268, 18·3%). It appears, therefore, that inhibitory bacteria in the human gut may play a role in inhibiting propagation of O157 and/or suppressing expression of virulence factors by this pathogen.

We compared the cost-effectiveness (CE) of an active case-finding (ACF) programme for household contacts of tuberculosis (TB) cases enrolled in first-line treatment to routine passive case-finding (PCF) within an established national TB programme in Peru. Decision analysis was used to model detection of TB in household contacts through: (1) self-report of symptomatic cases for evaluation (PCF), (2) a provider-initiated ACF programme, (3) addition of an Xpert MTB/RIF diagnostic test for a single sputum sample from household contacts, and (4) all strategies combined. CE was calculated as the incremental cost-effectiveness ratio (ICER) in terms of US dollars per disability-adjusted life years (DALYs) averted. Compared to PCF alone, ACF for household contacts resulted in an ICER of $2155 per DALY averted. The addition of the Xpert MTB/RIF diagnostic test resulted in an ICER of $3275 per DALY averted within a PCF programme and $3399 per DALY averted when an ACF programme was included. Provider-initiated ACF of household contacts in an urban setting of Lima, Peru can be highly cost-effective, even including costs to seek out contacts and perform an Xpert/MTB RIF test. ACF including Xpert MTB/RIF was not cost-effective if TB cases detected had high rates of default from treatment or poor outcomes.

Summary: In this paper we build on work investigating the feasibility of human immunodeficiency virus (HIV) testing in emergency departments (EDs), estimating the prevalence of hepatitis B, C and HIV infections among persons attending two inner-London EDs, identifying factors associated with testing positive in an ED. We also undertook molecular characterisation to look at the diversity of the viruses circulating in these individuals, and the presence of clinically significant mutations which impact on treatment and control.

Blood-borne virus (BBV) testing in non-traditional settings is feasible, with emergency departments (ED) potentially effective at reaching vulnerable and underserved populations. We investigated the feasibility of BBV testing within two inner-London EDs. Residual samples from biochemistry for adults (⩾18 years) attending The Royal Free London Hospital (RFLH) or the University College London Hospital (UCLH) ED between January and June 2015 were tested for human immunodeficiency virus (HIV)Ag/Ab, anti-hepatitis C (HCV) and HBsAg. PCR and sequence analysis were conducted on reactive samples. Sero-prevalence among persons attending RFH and UCLH with residual samples (1287 and 1546), respectively, were 1.1% and 1.0% for HBsAg, 1.6% and 2.3% for anti-HCV, 0.9% and 1.6% for HCV RNA, and 1.3% and 2.2% for HIV. For RFH, HBsAg positivity was more likely among persons of black vs. white ethnicity (odds ratio 9.08; 95% confidence interval 2.72–30), with anti-HCV positivity less likely among females (0.15, 95% CI 0.04–0.50). For UCLH, HBsAg positivity was more likely among non-white ethnicity (13.34, 95% CI 2.20–80.86 (Asian); 8.03, 95% CI 1.12–57.61 (black); and 8.11, 95% CI 1.13–58.18 (other/mixed)). Anti-HCV positivity was more likely among 36–55 year olds vs. ⩾56 years (7.69, 95% CI 2.24–26.41), and less likely among females (0.24, 95% CI 0.09–0.65). Persons positive for HIV-markers were more likely to be of black vs. white ethnicity (4.51, 95% CI 1.63–12.45), and less likely to have one ED attendance (0.39, 95% CI 0.17–0.88), or female (0.12, 95% CI 0.04–0.42). These results indicate that BBV-testing in EDs is feasible, providing a basis for further studies to explore provider and patient acceptability, referral into care and cost-effectiveness.

We investigated the positive predictive value (PPV) of a solitary positive immunoglobulin M (IgM) phase II response for the serodiagnosis of acute Q fever detected with either an indirect immunofluorescence assay (IFA) or an enzyme-linked immunosorbent assay (ELISA). Initial and follow-up sera from patients suspected of acute Q fever were included if initially only IgM phase II tested positive with IFA in 2008 (n=92), or ELISA in 2009 (n=85). A seroconversion for Q fever was defined as an initial sample being IgG phase II negative but positive in the follow-up sample. The PPV of an initial isolated IgM phase II result detected by IFA or ELISA was 65% and 51%, respectively, and therefore appeared not to adequately predict acute Q fever. For this reason it cannot be used as a diagnostic criterion nor should it be included in public health notification without confirmation with other markers or a follow-up serum sample.

One hundred and sixty-eight strains ofEscherichia coli isolated from 84 men and 84 women who had urinary tract infections (134 cases) or bacteremia of urinary tract origin (34 cases) were assessed for their carboxylesterase B electrophoretic types B and B α-haemolysin production, the presence of mannose resistant haemagglutinin (MRHA) and antibiotic susceptibility. Electrophoretic type B was phenotypically linked with α-haemolysin and MRHA productions. The strains isolated from males were more frequently of type B, haemolytic and both haemolytic and haemagglutinating than those isolated from females. The strains isolated during bacteremia were more frequently haemolytic and haemag glutinating than those obtained from urinary tract infections. Type B strains were more frequently resistant to antimicrobial agents than type B strains. The results reinforced the distinction, in terms of virulence and antibiotic sensitivity, between B and B strains and demonstrated the influence of the sex of patients on the host-parasite interaction during urinary tract infections.

The exotoxins produced by ten strains of C. ulcerans (two human, six bovine and two equine) have been studied. On the criteria of toxin–antitoxin neutralisation and immunoprecipitation tests using highly specific diphtheria and C. ovis antitoxins with crude toxic filtrates, (NH4)2SO4 concentrates, and partially purified chromatographic preparations of these, together with the presence or absence of inhibition of the action of staphylococcal beta-haemolysin, and the reaction produced when injected intradermally into rabbits, two toxins could be identified, namely diphtheria toxin and C. ovis toxin. There was no evidence for the production of a third toxin specific for C. ulcerans. Five strains produced both diphtheria and C. ovis toxins. In four diphtheria toxin predominated, but in the fifth C. ovis toxin predominated. Two strains produced only diphtheria toxin and two only C. ovis toxin, though there was good but not complete evidence that a third strain (Revell) also fell into this latter group. Considerable variation occurred in the concentration of each toxin and, where both were present, in the proportion of each.

Three hundred and twenty-two strains of Bacteroides fragilis isolated from infected patients at three different hospitals were tested against 20 type specific B. fragilis antisera using the tube agglutination technique. Of these strains 41·3% were assigned to a single O-serotype, a further 20·5% were agglutinated by several antisera and could not be classified and the remainder showed no reactions. Three different serotypes were prevalent in the three hospitals and minor geographical variation was observed.

No correlation was found between serotypes and the origin of infection, but those from the blood were the most readily typable strains. No correlation was found between serotypes and biotypes of B. fragilis.

This study assessed risk factors for 30-day mortality in 66 patients with carbapenem-resistant Acinetobacter baumannii (CRAB) infection or colonization during an outbreak in an intensive-care unit. Clinical and demographic characteristics were evaluated. The overall 30-day mortality was 47·0%. In the multivariate Cox regression model, septic shock [adjusted hazard ratio (aHR) 5·01, 95% confidence interval (CI) 2·32–10·01] and APACHE II score at onset of infection (aHR 1·11, 95% CI 1·04–1·18) were significantly associated with 30-day mortality. Administration of appropriate therapy was a protective factor, but it was not statistically significant (aHR 0·48, 95% CI 0·21–1·12). A sample of isolates tested (n=27) carried the blaOXA-23 gene. Severity of baseline condition and severity of infection presentation were major risk factors for mortality during the outbreak. Patients who received appropriate therapy tended to have lower mortality rates, although therapy was started late and dosage was suboptimal in most cases.

Serological responses to Cryptosporidium-specific antigens (15/17 and 27 kDa) were compared among populations in four areas of the Czech Republic that use drinking water from clearly defined sources: (1) wells in a fractured sandstone aquifer, (2) riverbank infiltration, or (3) two different filtered and chlorinated surface waters. Among persons surveyed in the area with riverbank-infiltration water, 33% had a strong serological response to the 15/17-kDa antigen group whereas, in the other three areas, over 72% of persons had a strong response. These response differences suggest that Cryptosporidium exposures and infection were lower in the area with bank infiltration. The large percentage of the study population with a strong serological response to both antigens suggests high levels of previous infections that may have resulted in protective immunity for cryptosporidiosis. This may be one reason why no waterborne cryptosporidiosis outbreaks and few cases of cryptosporidiosis have been reported in the Czech Republic.

An outbreak of echovirus 11 infection was observed in a children's home that housed 16 children. Nine children younger than 1 year shared a large room on the first floor, which contained a large basin. Three of them presented with aseptic meningitis with CSF and stool samples positive for echovirus 11. The other six infants who shared the room were asymptomatic but their stools were positive for echovirus 11. Seven infants aged 1–2 years stayed on the second floor and were asymptomatic. One of them had positive stool culture for echovirus 11. No virus was isolated from stool samples taken from the 26 staff members. However, serology was suggestive for recent echovirus 11 infection in seven asymptomatic staff members. All seven worked either exclusively on the first floor or alternately on both floors. Our survey demonstrated that echovirus 11 may spread very efficiently in children's homes. The rate of meningitis in the infected infants was 30% while all the recently infected adults were asymptomatic.

The data of two cohort studies of HIV-infected individuals were used to examine whether the rate of CD4 decline is a determinant of HIV progression, independent of the most recent CD4 count. Time from seroconversion to clinical AIDS was the main outcome measure. Rates of CD4 decline were estimated using the ordinary least squares regression method. AIDS incidences were compared in individuals who had previously experienced either a steeper or a less steep rate of CD4 decline. Cox proportional hazards model including a time-dependent covariate for the rate of CD4 decline was performed. The rate of prior CD4 decline was significantly associated with the risk of developing AIDS independently from the most recent CD4 count, with a 2% increase in hazard of AIDS (P<·01) for a difference of 10 cells/mm3 in the estimated yearly drop in CD4 count. This finding gives scientific credit to the belief that individuals with a prior steeper CD4 decline consistently have a higher subsequent risk of developing AIDS than those with a less steep prior decline.