The 2009 meningitis season in Niger was characterized by an early onset, beginning in the very first weeks of the year and peaking from the 12th to the 15th week with 5655 clinical cases over the 4 weeks. From 1 January 2009 to 28 June 2009 (week 26), a total of 13 733 clinical cases of meningitis were reported to the national epidemiological surveillance system with a case-fatality rate of 4·2%. During the season 25 of the 42 health districts reached the epidemic threshold and 11 the alert threshold. Reactive mass vaccination campaigns involving a total of 5 166 741 doses of the polysaccharide meningococcal bivalent (A+C) vaccine progressively controlled the outbreak in most parts of the country. A total of 3755 cerebrospinal fluid samples representing 28·1% of the suspected meningitis cases were analysed. Serogroup A meningococci were the causative agent in 97·5% of the meningococcal cases. Multi-locus sequence typing of 26 meningococal serogroup A strains showed 25 sequence type (ST)7 and one ST2859, both sequence types belonging to the ST5 clonal complex (CC5) of subgroup III. This is the largest epidemic observed in Niger since those of 1995–1996 (59 948 notified cases) and 2000 (14 633 notified cases).

We evaluated all fatal neonatal sepsis and pneumonia cases occurring in Alaska during 1992–2000. Risk factors were evaluated using a database of all births occurring during the study period. Of 32 cases, group B streptococcus (GBS) was isolated from 21% (all <7 days of age), Candida spp. from 19% (all >7 days of age), non-GBS Gram-positive bacteria from 50% (53% <7 days of age), and Gram-negative infections from 38% (58% <7 days of age). Infants born at <37 weeks gestation accounted for 72% of cases and had an increased risk of GBS [rate ratio (RR) 9·1, 95% confidence interval (CI) 2·0–41] and non-GBS (RR 40, 95% CI 16–101) disease. Neonatal sepsis mortality has become an outcome concentrated among pre-term infants. Aetiologies include GBS during the early neonatal period, Candida spp. during the late neonatal period, and other bacteria during both periods.

Oral anti-diabetic drugs (OADs) have been associated with community-acquired pneumonia (CAP). We aimed to validate the recording of CAP in the Spanish Database for Pharmacoepidemiological Research in Primary Care (BIFAP) for the future evaluation of OAD–CAP association. The incidence rate (IR/1000 person-years) of CAP in type 2 diabetes mellitus (T2DM) was also determined. In total, 2966 pneumonia records (2040 listed as diagnosis and 926 as identified from comments added by physicians) were identified from 76 009 patients with T2DM after the first OAD in 2002–2013. Data around the CAP date were reviewed: 1803 (60·9%) were classified as ‘probable CAP’ (confirmed by X-ray/laboratory, referral letters or CAP lung site); 589 (19·8%) as ‘no-case’ (486 had other illness, 78 previous CAP, 25 cancer); and 574 (19·4%) as ‘possible CAP’ (441 without confirmatory information, 133 with uncertain diagnosis or uncertain diagnosis date). In total, 74·2% and 31·4% of pneumonia records in the diagnosis and comments, respectively, were ‘probable cases’ (IR: 6·04), which increased to 90·5% and 42·9%, respectively, when the 441 ‘possible cases’ without confirmatory information were included (IR: 7·52). In summary, diagnosis had a high positive predictive value, and adding cases automatically detected from comments decreased that value significantly.

To compare the effects of subcutaneous and intradermal methods of administration of TAB vaccine for primary immunization against enteric infections an investigation was carried out on 257 Army recruits.

The general and local reactions were more unfavourable by the intradermal method. The agglutinin responses were better with the intradermal route.

Records of 171 cases of bacterial meningitis admitted to Nottingham hospitals from January 1974 to June 1980 were reviewed. The distribution of organisms producing meningitis and the factors influencing mortality in different age groups were assessed. Neisseria meningitidis, Haemophilus infiuenzae and Streptococcus pneumoniae accounted for 69% of all proven cases. The overall mortality was 26% being lowest in patients with meningococcal meningitis (0%) and highest in those with pneumococcal meningitis (53%). The following factors were associated with a poor prognosis: age more than 40 years, or less than 2 months; state of consciousness on admission; high CSF protein concentration; and a positive blood culture. There was no evidence that antibiotic therapy prior to admission affected prognosis. Although many laboratory findings were altered by prior treatment with antibiotics, this did not prevent the establishment of a diagnosis in the individual patient.

Bromine chloride, chlorine and peracetic acid inactivated f2 coliphage in effluent but in order to achieve 99·99% inactivation the three disinfectants were required at about 1, 10 and 100 mg/l respectively. The activity of chlorine was halved by the presence of added organic matter, whereas bromine chloride and peracetic acid were very little affected. When a second successive dose of virus was added to the reaction mixture, the virus was inactivated only by peracetic acid despite the fact that in the chlorine-treated effluent residual chlorine was detected. The addition of a second dose of disinfectant inactivated residual virus in the same way as the first dose.

M. fortuitum is a rapidly growing mycobacterium associated with community-acquired and nosocomial wound, soft tissue, and pulmonary infections. It has been postulated that water has been the source of infection especially in the hospital setting. The aim of this study was to determine if municipal water may be the source of community-acquired or nosocomial infections in the Brisbane area. Between 2007 and 2009, 20 strains of M. fortuitum were recovered from municipal water and 53 patients’ isolates were submitted to the reference laboratory. A wide variation in strain types was identified using repetitive element sequence-based PCR, with 13 clusters of ⩾2 indistinguishable isolates, and 28 patterns consisting of individual isolates. The clusters could be grouped into seven similar groups (>95% similarity). Municipal water and clinical isolates collected during the same time period and from the same geographical area consisted of different strain types, making municipal water an unlikely source of sporadic human infection.

Serum and cervical secretions were collected from patients with cervical dysplasia, carcinoma-in-situ (CIS), squamous cell carcinoma (cervical SCC), and controls with normal cervices, attending clinics within the West Lambeth Health District, London. Enzyme-linked immunosorbent assays were used to examine cervical secretory IgA (sIgA) and serum IgG and IgA antibodies to herpes simplex virus (HSV). Sexual and demographic factors were considered during data analysis, which involved fitting multiple linear or multiple logistic regressions to HSV antibody levels. Prevalence of sIgA-HSV and levels of serum antibodies to HSV in all groups were compared with those of gynaecology controls. Caucasian women with mild dysplasia had a significantly higher prevalence of sIgA-HSV. Serum IgG levels to HSV (IgG-HSV) were significantly elevated in women with mild dysplasia and severe dysplasia/ClS. Serum IgA levels to HSV1 (IgG-HSV1) were significantly higher in women with cervical SCC (after adjusting for smoking habits) and other genital tumours. Significantly higher levels of serum IgA to HSV2 (IgA-HSV2) were also found among Caucasian women with cervical SCC. The possible role of HSV as a co-factor in cervical carcinogenesis is discussed.

A study of the kinetics of inactivation of foot-and-mouth disease virus type SAT 2 strains revealed that in most cases the rate of neutralization was not rectilinear. Deviations from first-order kinetics observed represented biphasic or parabolic and stepwise reactions. The initial rate was rapid and showed no lag phase or shoulder. The effects of deviations from linearity could be minimized by dilution of antiserum to a suitable extent. Treatment of virus–antibody mixtures with anti-species globulin resulted in enhancement of the rate of neutralization of homologous and heterologous reactions without significantly altering the relation between the two. This treatment also considerably reduced the amount of the persistent fraction. In attempt to disaggregate virus it was observed that sodium dodecyl sulphate inhibited neutralization of virus by specific antiserum.

Previous workers (Stuart-Harris, Pownall, Scothorne & Franks, 1953; May, 1953)have reported studies on the bacterial flora of the sputum in cases of chronic bronchitis. Both pneumococci and Haemophilus influenzae have been reported frequently in the sputum but the source of these organisms, which might be either the patient's own upper respiratory tract or the environment, has not been traced.A long-term study of individuals with and without chronic bronchitis and of their families was therefore begun in an attempt to discern the role of exogenous infection in this disease. Observations were limited to the pneumococcus because serological identification of individual strains was readily possible in this species.

1. Pneumonic Plague epidemics arise as a secondary manifestation of Bubonic Plague.

2. The prevalence of purely septicaemic cases towards the end of the epidemic is significant as a probable explanation of its decline and termination.

3. Subacute or chronic plague may exist among tarabagans (Arctomys bobac) in Mongolia and Siberia, giving rise to periodical outbreaks of bubonic plague in man, as a result of direct infection from injury due to skinning by trappers or marmot eaters.

4. The tarabagan is easily susceptible to pneumonic plague produced by inhalation of B. pestis in spray form.

5. The existence of Pneumonic Plague carriers has been proved in the 1921 Manchurian epidemic.

6. Rooms where patients have died of pneumonic Plague are not particularly dangerous. In all four instances recorded, sick patients travelling in railway carriages have not infected their fellow passengers.

7. Disinfectants and antiseptics, even in strengths above those usually employed, have very little effect upon plague sputum. Alcohol is the surest means of sterilising the hands and gloves in plague work.

8. We have cultivated B. pestis from seemingly dry sputum of partients.

9. The mask is the principal means of personal protection against Pneumonic Plague.

10. The problem of successful vaccination against Pneumonic Plague still awaits solution.

1. A mixture of serum and its anti-serum has the property of fixing or deviating complement and thus interfering with haemolysis. In this there is a close analogy to the fixation of complements by cellreceptors in association with immune-bodies.

2. A large number of different complements may be fixed by the same combination of serum and anti-serum: some complements however may not be fixed.

3. The amount of homologous serum necessary to produce a distinct deviation of complement is extremely small—·000,01 c.c. and even less: as a rule it is many times less than the amount necessary to give a visible precipitate with the anti-serum.

4. When a precipitate forms, the deviating substance is present in the precipitate and may be so exclusively: precipitation is however not essential, as the deviation phenomenon may be given by an anti-serum without the formation of a precipitate.

5. The precipitin and deviation tests give results which are in great part in accord as regards specificity.

6. For any given amount of anti-serum there is an optimum amount of homologous serum which gives maximum deviation of complement: above as well as below the optimum the deviation diminishes.

7. The deviation phenomenon produces an effect similar to an “anti-complement” action and the views generally held with regard to anti-complements require revision. It is however still left an open question whether true anti-complements exist.

In August 2015 a gastroenteritis outbreak occurred following a wedding. An outbreak investigation was undertaken and a cohort study was conducted using an online survey. Of 140 guests, 134 received the survey and 113 responded (84·3% response rate). Seventy respondents met the case definition of vomiting and/or diarrhoea within 72 h of the wedding (61·9% attack rate). Fifteen exposures were associated with illness; on stratification, all were confounded by the ham hock starter. Multivariable analysis showed a significant association with exposure to ham hock (risk ratio 6·62, 95% confidence interval 2·19–20·03). Eight guests and two catering staff submitted stool samples. All tested positive for norovirus GI-6 infection, including a food handler who had vomiting less than 48 h before the wedding. A single genotype was detected among all samples, suggesting a single source of contamination. The transmission pattern suggested point-source exposure. The most plausible cause of the outbreak was transmission from an infected food handler via contaminated food. This highlights the importance of appropriate exclusions for symptomatic food handlers. Additionally, the food handler's stool sample was submitted 7 days after symptom resolution. The potential for extended viral excretion, and the extremely low infective dose of norovirus, may mean that current exclusion guidelines are not of sufficient duration.

1. A quantitative theory has been developed for the reactions between antigens and antibodies, applicable in particular to the precipitin reaction. The theory is equally applicable to unspecific precipitations, for instance the reaction between proteins and protein precipitating agents such as nucleic acids, etc.

2. The theory is based on the concept that the antigen-antibody interaction is governed by the same principles as the dissociation of a polybasic acid, HNT, where the antibody corresponds to the hydrogen ion H, and the antigen to the anion T. In their mutual reactions the antigen G is supposed to be polyvalent and the antibody A monovalent: hence the result of the interaction is a mixture of compounds ANG, AN-1G, …, AG.

3. A mathematical deduction is performed starting from the law of mass action, which leads to expressions for the amounts of total precipitate and its constituents in terms of the quantities of antigen and antibody which were mixed and the known equilibria constants.

4. A numerical example is given for a tetravalent antigen. Three cases are represented in graphical forms: the ‘X case’ without inhibition zones, the ‘Y case’ with one and the ‘Z case’ with two inhibition zones. Certain characteristics are described and the significance of the ‘equivalence point’ is analysed.

5. A discussion deals with the irreversibility in relation to the Danysz phenomenon and the dilution effect, and finally the parameters of the theory are more closely considered.

The objective of this study was to compare the occurrence of Salmonella spp. found in the animal environment in pig herds with different Salmonella risks (61 herds with low seroprevalence, 81 herds with high seroprevalence) on a broad scale. The environmental samples were divided into two types: direct (n=1105) and indirect (n=1220) environmental samples. All samples were tested for Salmonella spp. via real-time polymerase chain reaction. Most of the indirect environments were more often Salmonella-positive in the high-seroprevalence herds than in the low-seroprevalence herds; significantly higher were compartment aisles [odds ratio (OR) 3·45, 95% confidence interval (CI) 1·61–7·41], driving boards (OR 3·06, 95% CI 1·38–6·92) and the central aisle of the barn (OR 3·03, 95% CI 1·35–6·83). The overall results show that especially areas in the indirect environment are the major, but mostly underestimated causes of residual Salmonella.

We report key learning from the public health management of the first two confirmed cases of COVID-19 identified in the UK. The first case imported, and the second associated with probable person-to-person transmission within the UK. Contact tracing was complex and fast-moving. Potential exposures for both cases were reviewed, and 52 contacts were identified. No further confirmed COVID-19 cases have been linked epidemiologically to these two cases. As steps are made to enhance contact tracing across the UK, the lessons learned from earlier contact tracing during the country's containment phase are particularly important and timely.

A case-controlled study of the incidence of heat-labile enterotoxin-producing Escherichia coli (LT+ETEC) and other enteric pathogens in travellers returning to the Sheffield area was conducted from May 1984 to April 1986. LT+ETEC were found in 35 (5.8%) of 600 travellers to developed countries (mainly popular Mediterranean holiday resorts), 36 (11.3%) of 320 travellers to less-developed countries, and 11 (0.9%) of 1282 control patients whose illness was not associated with recent travel abroad. A seasonal peak of LT+ETEC infection was observed only in travellers to developed countries, with infections being significantly commoner in August to October. There was no significant deviation from expected age/sex distribution of LT+ETEC infection. Strains of LT+ETEC from travellers produced more toxin than strains from control patients, strains from travellers to less-developed countries producing most of all.

The number of band differences in DNA macrorestriction profiles required to distinguish unrelated strains from an index strain varies in an outbreak with the species and restriction enzyme used. In order to define this difference for epidemiological studies of Serratia marcescens, we produced DNA fingerprints from 57 isolates of the organism using the restriction enzyme XbaI and pulsed-field gel electrophoresis (PFGE). The isolates were selected on the basis of their epidemiology, serotype and phage-typing patterns to include 28 unrelated strains and 29 representatives from 2 distinct outbreaks. One of the outbreaks was prolonged, lasting for several years. Electrophoretic profiles consisting of 20 or more clearly resolved bands were obtained for all isolates. Twenty-six of the unrelated strains had unique profiles with over 10 band differences from all other strains, while 27 of the outbreak representatives could be assigned to the appropriate outbreak with confidence. The majority of the outbreak isolates had none or 2 band differences from the index profile, although 3 isolates differed by 5–7 bands. The 2 exceptions among the unrelated strains differed by 4 bands, and 3 phage typing reactions, and were isolated from London and Berlin 3 years apart, while the 2 exceptions among the outbreak collection had clearly unique profiles with over 20 band differences from each other and the outbreak profiles. Cluster analysis using Dice coefficient and UPGMA gave cut-off values of 75–78% similarity overall for related isolates, while the closest similarity for unrelated strains was 70%. The results of this study together with those of the 6 previous reports of PFGE for S. marcescens (which used either enzymes XbaI or SpeI) confirm that this technique is of value for this species and that with XbaI at least, most epidemiologically related strains will only differ by 3–4 bands. However, on occasion up to 7 band differences can be found within an apparent outbreak, which may be suggestive of genetic drift.

In the present study an attempt has been made to determine the relative importance of several factors on the mortality rates of infancy. In view of the differences in the rates at the several ages under one year and of the differential decline in these rates within recent years, it has been suggested that for any complete consideration of the death rates in infancy, some subdivision of the rate, either of a biological or temporal character, must be effected, and each of these subdivisions examined separately. The infant mortality rate has been treated in three broad categories, namely, the antenatal, neo-natal and post-natal death rates; and it has been shown that each of these depends on different factors.

Considered as death rates per unit of time the neo-natal rate is much higher than at any other period of life. The ante-natal death rate is much lower than this, and the post-natal rate lowest of all.

In relation to these rates, the influence of three, presumably important, factors have been measured. These are:

1. The provision of skilled attendance to mothers in childbed.

2. The health of the mothers.

3. Environmental and social conditions.

The indices used as measures of these three variables and their limitations have been pointed out. The author feels only too conscious of these limitations and, with such vital statistical data as the only indices available of the factors the influence of which on the mortalities of infancy it is desired to measure, it is probable that any conclusions drawn from such an analysis should be accepted with some degree of caution and reserve. Nevertheless. I am firmly convinced that even these (to the clinician and administrator) rather crude results are immeasurably superior to expressions of opinion, unsupported by facts, so frequently found forming the basis of much of the medical literature on the subject. That we have so relatively little exact quantitative knowledge of the influential factors concerned in the growth, nutrition and mortality of infants is surely not for lack of opportunity of collecting the requisite data. An admirable machinery for such a purpose—the various maternity and child welfare centres—is in extensive operation throughout this country; and if the medical officers in charge of these centres could only be persuaded to collect and analyse (or have analysed) periodically the data contained in suitably framed and completed questionnaires, many questions of scientific importance as well as of the efficacy of administrative efforts would soon cease to be subjects of controversy.

Our results show that, of these factors, only the provision of skilled medical assistance to mothers in childbed is of importance in connection with antenatal mortality. The general health of the mother and external environmental conditions have no direct influence on the death rate at this period of life. The magnitude of the correlation leads to the further conclusion that a great part of the still-birth rate is not to be controlled by improvements in even all of these factors.

The neo-natal death rate is related both to variations in external environment and in the obstetrical assistance available for mothers in childbed. At this state of life, again, the health of the mother has no substantial influence on the death rate. External surroundings and the quality of the obstetrical assistance afforded to the mother are of approximately equal importance in determining these rates; but here again the conclusion is advanced that the greater part of the death rate at this stage of life is beyond human efforts of control.

The post-natal death rate seems to offer the greatest scope for administrative measures. In this case the health of the mother would appear to come first in order of importance, environment also is of some importance, whereas the effects of variations in obstetrical services have now ceased to be reflected on the mortality of infancy.

In isolated rural communities there is a part of the post-natal death rate which could be eliminated by the speedy arrival of skilled medical assistance.

Foreign statistics have been collected and analysed to enquire into the causation of still-births. An obvious defect in these was pointed out, namely, the large proportion of deaths due to unknown causes. A comparison of these figures with those collected from several maternity hospitals has shown that hospital figures give a biassed view of the problem. The proportion of deaths due to causes in which the life of the mother as well as that of the foetus is endangered is greatly magnified, and consequently will produce a too optimistic estimate of the amount of amelioration which will result from increased attention to pregnant and parturient women. The statistics which have been given in this section show that in a really random sample of the population only a small proportion of still-births is the result of causes which can be controlled by this method, and that the chief causes of ante-natal death are developmental defects of the foetus and prematurity.

A short study has been made of certain statistico-anatomical features of the foetus and infant. From this it has been inferred that the foetus is physically in a state of extreme instability, that the conditions which kill in utero are rapidly fatal to the foetus, and that this instability is a somewhat more prominent feature in the male than in the female. As infancy advances, visceral variability decreases steadily, so that it would seem probable that some time is necessary for the foetus to adapt itself to its new mode of existence after birth. This state of unstable equilibrium in early life may provide some reason for the higher mortalities at these ages.

The spread of the Zika virus (ZIKV) in the Americas led to large outbreaks across the region and most of the Southern hemisphere. Of greatest concern were complications following acute infection during pregnancy. At the beginning of the outbreak, the risk to unborn babies and their clinical presentation was unclear. This report describes the methods and results of the UK surveillance response to assess the risk of ZIKV to children born to returning travellers. Established surveillance systems operating within the UK – the paediatric and obstetric surveillance units for rare diseases, and national laboratory monitoring – enabled rapid assessment of this emerging public health threat. A combined total of 11 women experiencing adverse pregnancy outcomes after possible ZIKV exposure were reported by the three surveillance systems; five miscarriages, two intrauterine deaths and four children with clinical presentations potentially associated with ZIKV infection. Sixteen women were diagnosed with ZIKV during pregnancy in the UK. Amongst the offspring of these women, there was unequivocal laboratory evidence of infection in only one child. In the UK, the number and risk of congenital ZIKV infection for travellers returning from ZIKV-affected countries is very small.