In 1962 the Public Health Laboratory Service (PHLS) became responsible for the Poliomyelitis Surveillance Scheme for England and Wales, which since 1970 has included the World Health Organisation (WHO) enquiry into Acute Persisting Spinal Paralysis. All the records have been kept, including those of patients who were later considered not to have had poliomyelitis. This paper reviews the cases between 1970–84 of patients normally resident in England and Wales, where the clinical features of the illness were considered by the clinician in charge to be those of poliomyelitis and in which either poliovirus was isolated or there was serological evidence of recent infection. Seventy cases met these criteria. Two patients died. A wild strain of poliovirus was isolated in 19 cases; a vaccine-like strain in 27; an intermediate strain in 5; and in 19 cases the strain was not known or there was no isolate. Eleven patients had a history of overseas travel; 17 had been vaccinated recently; and 12 had been in contact with a recent vaccinee. In the remaining 30 cases, the source of the infection was not found. Other details, including the age distribution, vaccination history and the laboratory findings are discussed.

In August 2012, an explosive outbreak of severe lower respiratory tract infection (LRTI) due to Streptococcus pneumoniae serotype-8 occurred in a highly vaccinated elderly institutionalized population in England. Fifteen of 23 residents developed LRTI over 4 days (attack rate 65%); 11 had confirmed S. pneumoniae serotype-8 disease, and two died. Following amoxicillin chemoprophylaxis and pneumococcal polysaccharide vaccine (PPV) re-vaccination no further cases occurred in the following 2 months. No association was found between being an outbreak-associated case and age (P = 0·36), underlying comorbidities [relative risk (RR) 0·84 95% confidence interval (CI) 0·34–2·09], or prior receipt of PPV (RR 1·4, 95% CI 0·60–3·33). However, the median number of years since PPV was significantly higher for cases (n = 15, 10·2 years, range 7·3–17·9 years) than non-cases (n = 8, 7·2 years, range 6·8–12·8 years) (P = 0·045), provided evidence of waning immunity. Alternative vaccination strategies should be considered to prevent future S. pneumoniae outbreaks in institutionalized elderly populations.

The purpose of the investigation was to examine the reason for the relative age shift in the incidence of diphtheria. The disease has been represented as now concentrating on children of school ages. We analysed, for various quinquennial periods beginning with 1901–5, the statistics of the notifications and deaths according to age and sex in the London boroughs which we classified into four social classes where I to IV represented descending order in the social scale. The conclusions arrived at were:

I. The age shift as represented by the ratio of the mortality at ages 0–4 to ages 5–9 years which has taken place in London has been found to occur mainly in the poorer districts. The ratio in the residential districts has not altered appreciably during the thirty years under review (Table V).

II. The age shift is also indicated by the morbidity statistics for the three quinquennial periods, 1901–5, 1909–13 and 1919–23, as there was a significant increase in the mean age of attack of children under 15 years of age.

The case rate at ages 5–14 during 1929–33 as compared with that in 1901–5 has increased most amongst children in the lowest social group.

III. Each of the variables (a) the decrease in the birth-rate between 1911 and 1931 in each London borough—an index of the change in the size of family—and (b) the decrease in infant mortality—a measurement of environmental improvement—is positively and significantly correlated with (c) the corresponding change in the size of the ratio of the case rates at ages 0–4 to 5–9 years. The coefficients were:

but the partial correlation coefficients

indicate that the change in the size of family is the more important factor as the value of rac.b is fairly large and significant, whereas the correlation between the change in the ratio and the environmental improvement when the effects of the decreasing birth-rate are made constant—rbc.a—becomes statistically unimportant.

The prediction of prognosis is an important part of management in hepatitis B virus (HBV)-related decompensated cirrhosis patients with high long-term mortality. Lactate is a known predictor of outcome in critically ill patients. The aim of this study was to assess the prognostic value of lactate in HBV-related decompensated cirrhosis patients. We performed a single-centre, observational, retrospective study of 405 HBV-related decompensated cirrhosis patients. Individuals were evaluated within 24 h after admission and the primary outcome was evaluated at 6-months. Multivariable analyses were used to determine whether lactate was independently associated with the prognosis of HBV-related decompensated cirrhosis patients. The area under the ROC (AUROC) was calculated to assess the predictive accuracy compared with existing scores. Serum lactate level was significantly higher in non-surviving patients than in surviving patients. Multivariable analyses demonstrated that lactate was an independent risk factor of 6-months mortality (odds ratio: 2.076, P < 0.001). Receiver operating characteristic (ROC) curves were drawn to evaluate the discriminative ability of lactate for 6-months mortality (AUROC: 0.716, P < 0.001). Based on our patient cohort, the new scores (Model For End-Stage Liver Disease (MELD) + lactate score, Child–Pugh + lactate score) had good accuracy for predicting 6-months mortality (AUROC = 0.769, P < 0.001; AUROC = 0.766, P < 0.001). Additionally, the performance of the new scores was superior to those of existing scores (all P < 0.001). Serum lactate at admission may be useful for predicting 6-months mortality in HBV-related decompensated cirrhosis patients, and the predictive value of the MELD score and Child–Pugh score was improved by adjusting lactate. Serum lactate should be part of the rapid diagnosis and initiation of therapy to improve clinical outcome.

Varicella is one of the most common childhood diseases. The course of the disease is usually mild and uncomplicated. In Slovenia, varicella is a notifiable communicable disease which must be reported. Data collected from 1979–98 were analysed. Over the 20-year period the number of varicella cases reported ranged from a low of 11 086 (in 1994) to a maximum of 21 141 (in 1987). During the last 10 years, the highest incidence of varicella was reported in children aged from 12 months to 2 years. In adults over 20, incidence has slightly but steadily increased over the 20 year period. Overall, the number of males with varicella exceeded that of females. The proportion of females was higher only in the 20–30-year age group, probably as a consequence of more frequent and closer contact with infected children by mothers. The highest number of reported cases was during winter and early spring.

Human strains of Mycobacterium tuberculosis were divided into the ‘Classical’ and ‘Asian’ types according to their sensitivity to thiophen-2-carboxylic acid hydrazide. The isolation of these two types in South-East England was studied during a seven-year period (1977–1983). The ‘Asian’ type was more prevalent among ethnic Asian patients than among ethnic Europeans. Among Europeans there was a decline in the isolation rate of ‘Classical’ strains and a small but significant increase in ‘Asian’ strains during the study period, so that the proportion of the latter type in this group is increasing. The type of bacillus was unrelated to the site of isolation except that the incidence of lymphadenitis due to the ‘Asian’ type among European females was significantly higher than expected. In general, European patients tended to be older than Asian patients, and the differences in age distribution according to site of isolation and type of bacillus in each ethnic group were small. A notable exception occurred with European females infected with the ‘Asian’ type, whose age distribution was similar to the Asians.

In view of the differences in behaviour of the two types of human tubercle bacilli in this country there is a need to cintinue a bacteriological surveillance and also to determine whether the nature of the host–pathogen interaction varies according to the type of bacillus.

The detection of Legionella pneumophila in water via guinea-pig intraperitoneal injection has been compared with direct isolation of these organisms on semiselective BCYEα media. Both techniques were of similar sensitivity, detecting as few as 102L. pneumophila in 10 ml of water. However, at this concentration, detection using guinea-pig intraperitoneal injection was via the indirect parameters of antibody production and immunofluorescent microscopy. Isolation of L. pneumophila from guinea-pig tissue for further investigation required > 107 organisms injected and in this respect is relatively much less sensitive than direct isolation on semiselective BCYEα media. Since L. micdadei and L. longbeachae are inhibited by one of the selective supplements used, other supplements and techniques need to be developed in order to avoid possible inhibition of other Legionella species.

The majority of those infected and affected by HIV are younger adults. The ability of highly active antiretroviral therapies (HAART) to extend survival means that those infected when younger may reach older age, and future increases in numbers of older individuals living with HIV in England, Wales and Northern Ireland (E,W&NI) are expected. Evidence that older individuals engage in risky sexual behaviours suggests potential for HIV transmission. Data from national HIV/AIDS surveillance systems were reviewed (1997–2001). An older individual is defined as aged 45 years or over. Between 1997 and 2001, 2290 older individuals were diagnosed with HIV; 361 in 1997, rising to 648 in 2001. Heterosexual acquisition accounted for 1073 (47%) infections; 662 were male. Where reported, 666 (65%) older heterosexuals were probably infected in Africa, 144 (14%) in the United Kingdom and 113 (11%) in Asia. There were 1020 (45%) new diagnoses acquired homosexually; white (92%), infected in the United Kingdom (78%). Numbers of older individuals accessing HIV-related services more than doubled between 1997 (2488) and 2001 (5175). In 2001, 2270 (53%) were London residents. Between 1997 and 2001, among HIV-infected older individuals attending genitourinary medicine (GUM) clinics, the proportions previously undiagnosed were 60% and 82% in heterosexual males and females respectively, and for men who have sex with men (MSM), 42%. Numbers of older individuals newly diagnosed with HIV have increased in recent years. The increase in numbers of older individuals accessing HIV-related services were in excess of younger adults. A significant proportion of older HIV-infected female heterosexuals and MSM were undiagnosed. Awareness must be raised among clinicians, and an ‘aged response’ to HIV is required.

A survey of national animal influenza surveillance programmes was conducted to assess the current capacity to detect influenza viruses with zoonotic potential in animals (i.e. those influenza viruses that can be naturally transmitted between animals and humans) at regional and global levels. Information on 587 animal influenza surveillance system components was collected for 99 countries from Chief Veterinary Officers (CVOs) (n = 94) and published literature. Less than 1% (n = 4) of these components were specifically aimed at detecting influenza viruses with pandemic potential in animals (i.e. those influenza viruses that are capable of causing epidemic spread in human populations over large geographical regions or worldwide), which would have zoonotic potential as a prerequisite. Those countries that sought to detect influenza viruses with pandemic potential searched for such viruses exclusively in domestic pigs. This work shows the global need for increasing surveillance that targets potentially zoonotic influenza viruses in relevant animal species.

We performed a seroepidemiological study of Toxoplasma gondii infection in free-range chickens from October 2012 to May 2013. We used cross-sectional two-stage cluster sampling to collect blood samples from wing veins of 601 chickens from central Ethiopia. T. gondii-specific antibodies were assayed by modified agglutination test (MAT). We collected information about risk factors by questionnaire and used univariable and multivariable logistic regression to assess risk factors. An overall seroprevalence of 30·5% [95% confidence interval (CI) 26·27–34·14] and 54·2% (95% CI 47·06–61·36) was found at animal- and flock-level, respectively. The MAT end titre of seropositive chickens (n = 183) were 1 : 60 in 46, 1 : 180 in 28, 1 : 540 in 29, ⩾1 : 1620 in 48, 1 : 6000 in 22, 1 : 18 000 in five, 1 : 54 000 in one, and ⩾1 : 162 000 in four. Animal-level risk factors identified using multivariable logistic regression model were: midland altitude [odds ratio (OR) 2·53, 95% CI 1·12–5·72], cross and exotic breeds (OR 3·17, 95% CI 1·39–7·23), increased age of chickens (OR 2·32, 95% CI 1·19–4·49), extensive management (OR 6·92, 95% CI 1·34–35·86) and the presence of cats (OR 2·08, 95% CI 1·20–3·61). Similarly, flock-level risk factors were midland altitude (OR 3·62, 95% CI 1·31–9·99) and the presence of cats (OR 1·19–4·94). The knowledge of the local people about the health risk of cats to humans and animals is poor. Housing and management of cats and chickens are also poor. The widespread presence of T. gondii infection in free-range chickens of Central Ethiopia provides suggestive evidence for the high level of contamination of the living environment of people with T. gondii oocysts. Meat from free-range chickens might be an important source of infection for humans. Altitude, breed, age, management and presence of cats are independent predictors of seropositivity. Education of farmers about toxoplasmosis and further studies to elucidate the burden of toxoplasmosis in animals and humans warrants consideration.

Understanding the spatial distribution of disease is critical for effective disease control. Where formal address networks do not exist, tracking spatial patterns of clinical disease is difficult. Geolocation strategies were tested at rural health facilities in western Kenya. Methods included geocoding residence by head of compound, participatory mapping and recording the self-reported nearest landmark. Geocoding was able to locate 72·9% [95% confidence interval (CI) 67·7–77·6] of individuals to within 250 m of the true compound location. The participatory mapping exercise was able to correctly locate 82·0% of compounds (95% CI 78·9–84·8) to a 2 × 2·5 km area with a 500 m buffer. The self-reported nearest landmark was able to locate 78·1% (95% CI 73·8–82·1) of compounds to the correct catchment area. These strategies tested provide options for quickly obtaining spatial information on individuals presenting at health facilities.

Brodifacoum was evaluated in the laboratory against the two gerbils, Tatera indica and Meriones hurrianae and the house rat, Rattus rattus. The acute oral LD50 for these rodents was found to be 0·10 mg/kg, 0·083 mg/kg and 0·77 mg/kg respectively. Feeding tests with 0·002% and 0·005% brodifacoum produced a 100% mortality after a 3-day feeding period in the gerbils and after a 4-day period in R. rattus. The anticoagulant is toxic at both the concentrations to all three species but is less palatable in comparison to plain baits. Results of this laboratory evaluation indicates that 0·002% brodifacoum-treated bait can be effectively used against T. indica, M. hurrianae and R. rattus.

Isolates of Salmonella typhimurium, recovered over a 9-month period from a child with gastroenteritis, were characterized by biotyping, phage-typing and plasmid-profile analysis. Because the data from the different methods were discrepant, it was difficult to establish whether her infection was due to a single strain that had changed character in vivo or was due to recurrent infections with different, unrelated strains. Restriction-enzyme fingerprinting of the plasmids from the different isolates provided an explanation for the initial discrepancy and highlighted a source of potential confusion in epidemiological studies.

Acute blood samples from 120 children, attending the fever hospital in Alexandria and complaining of fever, were collected and examined for haemagglutination-inhibiting (HAI) and complement-fixing (CF) antibodies against the following arbovirus antigens; Sindbis, West Nile (WN), yellow fever, dengue 1, sandfly fever, Quaranfil, Chenuda and Nyamanini. Positive reactions in the acute sera were only detected against Sindbis (4·3%) and WN (4·3%) antigens. The convalescent sera obtained from 48 of these children showed a pronounced HAI titre against WN antigen in 14·6 % of them. The same sera showed a lower titre against yellow fever antigen (Asibi strain) which is due to cross-reaction between the two viruses. None of the acute or the convalescent sera showed CF antibodies against Quaranfil, Chenuda or Nyamanini antigens. The convalescent sera were not tested against dengue type 1 antigen. It is suggested that of the known arboviruses in Egypt, WN is the most important from the public health point of view.

1. Scarlatinal streptococci obtained from the throats of cases of scarlet fever can be divided into various groups by means of agglutination and absorption tests. The same type of streptococcus can on occasion originate at least five separate clinically distinguishable diseases, namely, scarlet fever, tonsilitis, erysipelas, puerperal fever, and broncho-pneumonia, and it would appear that, so far as streptococcic infections are concerned, the nature of the disease entity is determined by the toxigenic qualities of the type of streptococcus, by the susceptibility or insusceptibility of the individual as determined by the absence or presence of the specific antibodies in the blood, and by the site of the infection itself (see p. 330).

2. Strong corroboration for the view that the S. scarlatinae is the causal organism of scarlet fever is obtained from the following findings, viz.:

(a) S. scarlatinae have been isolated from the throat brushings of practically all acutely ill scarlet fever patients (see p. 329).

(b) The whole clinical picture of scarlet fever going on to marked desquamation is produced by the subcutaneous injection of the exotoxin derived from the S. scarlatinae, the exotoxin having been haeated to 55° C. for one hour, with a view to destroying any filterable living virus which might be associated with the filtered exotoxin (see p. 342).

(c) In the Schultz-Charlton reaction the blanching of the scarlet fever rash is caused by the serum of a horse immunised against S. scarlatinae and its toxins.

(d) Dick-positive and Dick-negative reactions as produced by the intradermal injection of the streptococcus toxin have the closet correspondence to the degree of susceptibility or immunity to scarlet fever of the respective reactors (see p. 334).

(e) Susceptible nurses once they are actively immunised by injections of scarlatinal streptococcus toxin have been shown to be immune to the toxin of scarlet fever (see p. 337), and susceptible school children similarly inoculated are likewise immune (see p. 338).

(f) Return cases of scarlet fever can be prevented by actively immunising susceptible contacts with scarlatinal streptococcus toxin prior to the scarlet fever patient being discharged from hospital (see p. 339).

(g) Susceptible contacts can be safeguarded from taking scarlet fever by passively immunising them with a sufficient does of antistreptococcus serum obtained from a horse wich has been immunised by injections of S. scarlatinae and its toxin (see p. 349).

3. The limitations of the Schultz-Charlton reaction as an aid in the diagnosis of scarlet fever have been confirmed (see p. 330).

4. Evidence has been obtained which firmly establishes the value of the Dick suseptibility test as a measure of susceptibility to scarlet fever (see p. 332).

5. Extensive corroboration of the value of the Schick test as a measure of susceptibility to diphtheria has been obtained (see p. 334).

6. The efficacy of active immunisation against scarlet fever by means of scarlatinal streptococcus toxin injections has been demonstrated by the fact that, while scarlet fever has been present in epidemic form in Aberdeen, no nurses or maids in Aberdeen City Hospital have contracted scarlet fever since June 1st, 1925, from which date the nursing and domestic staffs of the hospital have been actively immunised before being admitted for duty to the scarlet fever wards; whereas, prior to that date, an average of 8·5 nurses, or 9·5 per cent. of the nursing staff, and 1·4 maids, or 4·2 per cent. of the domestic staff. annually suffered from scarlet fever (see p. 337).

7. Coincident with the disappearance of scarlet fever in the immunised nursing staff of the City Hospital, there has been a notable increase in the incidence of streptococcic tonsilitis in these immunised nurses, and the streptococci obtained from these cases of tonsilitis in nurses commonly fall into one or other of the serological groups of scarlatinal streptococci; and accordingly it would appear to be proved that immunised nurses, while protected by immunisation from the toxic effects of the exotoxin of S. scarlatinae, are not protected against tonsilitis due to S. scarlatinae (see p. 338).

Periodic outbreaks of West Nile virus (WNV), Eastern equine encephalitis virus (EEEV) and to a lesser extent, California serogroup viruses (CSGV), have been reported in parts of Canada in the last decade. This study was designed to provide a broad assessment of arboviral activity in Quebec, Canada, by conducting serological surveys for these arboviruses in 196 horses, 1442 dogs and 485 humans. Sera were screened by a competitive enzyme linked immunosorbent assay and positive samples confirmed by plaque reduction neutralisation tests. The percentage of seropositive samples was 83·7%, 16·5%, 7·1% in horses, 18·8%, 0·6%, 0% in humans, 11·7%, 3·1%, 0% in adult dogs and 2·9%, 0·3%, 0% in juvenile dogs for CSGV, WNV and EEEV, respectively. Serological results in horses and dogs appeared to provide a meaningful assessment of risk to public health posed by multiple arboviruses.

1. By means of a new technique, using the “closed bowl” of the Sharpies-Super Centrifuge, in which the distance which the virus particles have to travel under the influence of a given centrifugal force until they are caught mechanically in an agar-gel lining the wall of the bowl amounts to only a few tenths of a millimetre, the potency of 5 c.c. of a foot-and-mouth disease virus suspension can be reduced by 90–99 per cent in 3 min. using a centrifugal force of 24,000 times gravity. The virus can be recovered without loss by extraction of the agar-gel either in fresh medium or even in the liquid layer or “supernatant”, thus showing that adsorption phenomena play no role whatever in the effects obtained by centrifugation.

2. The non-adsorbability of the virus by the agar, however, is determined by the presence of a certain though very small amount of impurities presumably protein which seem to have a “protective” effect. The limit of nonadsorption of the virus by the gel appears to be in that region of “purity” where the sulphosalicylic acid test for protein is negative whereas serological precipitation reactions for host protein are still positive. Virus purified beyond this limit is strongly adsorbed by an agar-gel.

3. Measurements of the sedimentation rate were made on three strains of virus of different type Vallee A, Vallee 0 and Waldmann C and no differences between the three strains were observed. The average diameter of the virus particles determined from the sedimentation rate data was 20 mμ. All the evidence now available for the monodispersity of the virus is discussed. The fact that the infective particles are uniform in size indicates that the measurements recorded here concern actually the single virus elements.

4. The sedimentation equilibrium of the virus has been estimated. The value calculated on this basis for the weight of a single virus particle is circ. 1 × 10−17 g. The diameter of a sphere of this weight and density 1·30 would be 25 mμ. The size values for the virus, 25 mμ estimated from sedimentation equilibrium data and 20 mμ estimated from sedimentation rate data, are discussed in relation to the possible shape of the virus particles.

5. The virus can be sedimented in sucrose and sucrose-salt solutions of densities up to 1·28. On the basis of the sedimentation rates in these media the specific gravity of the virus particles is estimated to be about 1·40. This value however may be abnormally high due to the dehydrating effect of the high concentration of salt or sugar. The application of the centrifuge technique described here to the concentration and purification of the virus of foot-andmouth disease in conjunction with ultrafiltration methods will be the subject of a second paper by Galloway & Schlesinger (1937).

Attempts were made to stimulate acquired immunity to experimental Absidia ramosa infection in mice. Unprotected animals inoculated with large doses of A. ramosa spores frequently developed acute phycomycosis of the central nervous system. Mice previously exposed to sub-lethal doses of spores showed a high resistance to subsequent challenge with A. ramosa. No consistent increase in resistance was observed in mice vaccinated with killed A. ramosa spores, hyphal walls, intracellular mycelial antigens or various combinations of these, with Freund's incomplete adjuvant.

Antibodies to soluble mycelial antigens were inconsistently present in the sera of mice vaccinated with sub-lethal doses of viable spores. They were generally present in the sera of animals vaccinated with mycelial extracts or hyphal walls but not killed spores.

Delayed hypersensitivity reactions to A. ramosa mycelial antigens could usually be elicited by intradermal tests in mice exposed to viable spores but irregularly in those vaccinated with non-viable preparations. Positive reactions were also frequently given by older mice not deliberately exposed to A. ramosa.

Although mice previously exposed to viable A. ramosa spores were highly resistant to intravenous or intracerebral challenge with this fungus, they were more likely to develop persistent local granulomata on subcutaneous injection of spores than were unvaccinated animals.

A longitudinal study of nasal colonization and hand contamination of food handlers with Staphylococcus aureus commenced in 2002 prior to the outbreak of severe acute respiratory syndrome. In the follow-up in 2003 when hygiene measures were strictly implemented, significant reductions in carriage were observed. To investigate if this change was sustained, nasal and hand carriage rates were compared between the earlier studies and a further sampling in 2011. The initial nasal carriage rate was 35% and hand contamination 41·2%, decreasing to 23·5% and 11·6%, respectively in 2003 (P < 0·001). In 2011, nasal carriage was similar to 2003 (22·9%), while hand contamination dropped further to 3·7% (P < 0·001). Spa-typing revealed 39 types in 2002 and 42 in 2011. This study reveals that the marked reduction in colonization had been sustained. This may be attributed to reduced opportunities for spread due to enhanced hygiene and reinforces its importance for control of disease.

We undertook a retrospective descriptive comparison of the spectrum of pathogens responsible for bacteraemia and diarrhoea in HIV antibody positive and negative patients over 4 years (1988–92), in Nairobi, Kenya. The study population was recruited from primary to tertiary centers of clinical care and consisted of 2858 adults (15 years or older). There were 415 significant blood culture isolates, 192 from 1785 HIV negative patients and 223 from 953 HIV positive patients. There were 233 significant faecal isolates, 22 from 115 HIV negative patients and 211 from 531 HIV positive patients. The most common pathogens detected in blood were Streptococcus pneumoniae and Salmonella typhimurium and in faeces Shigella flexneri, S. typhimurium and Cryptosporidium parvum. The agents causing illness in HIV positive patients in Nairobi are similar to those prevalent in the HIV negative community and the investigation of a febrile illness with or wothout diarrhoea in an HIV positive patient should reflect this.