The serological responses of conventionally reared sheep were compared after vaccination with inactivated parainfluenza 3 (PI3) virus incorporated in three different adjuvants. Inactivated PI3 virus with the double-stranded RNA, BRL 5907 in an oil emulsion was shown to stimulate higher serum antibody titres over the first 5 weeks after vaccination than virus with and without BCG emulsified in oil. The ability of this vaccine to protect specific pathogen-free lambs against challenge with PI3 virus was examined in a second experiment. In this experiment the vaccine stimulated virus neutralizing and haemagglutination inhibiting antibodies in the serum. After intranasal and intratracheal inoculation with PI3 virus at challenge, vaccinated lambs showed no clinical illness and virus isolation was confined, except in one lamb, to the first two days. In contrast, unvaccinated lambs developed respiratory disease and virus was isolated daily for 7 days after challenge.

A description is given of a simple method of determining the sensitivity of bacteria to sulphonamides by means of impregnated blotting-paper disks applied to nutrient agar prepared from broth freed from sulphonamide antagonists by incubation with lysed horse red blood cells.

With organisms sensitive to the selected sulphonamide, a zone of inhibition of growth will occur, the diameter of which is related to the concentration of the sulphonamide necessary to inhibit growth. Sensitivity to several sulphonamides can be determined simultaneously.

The impregnated disks can be stored without loss of potency.

Because syndromic surveillance systems use pre-diagnostic data for early detection of disease outbreaks, it is important to know how the earliest signs and symptoms of a disease might appear in these systems. The available medical literature describing the sequence of signs and symptoms of pneumonic plague reveals that, during the earliest stages, patients will most likely present with certain gastrointestinal and minimal, if any, respiratory signs. Without this knowledge, early evidence of pneumonic plague in syndromic surveillance systems may be missed until the respiratory signs become prevalent. Because plague is a zoonotic disease, new syndromic surveillance systems that use animal data from park rangers and veterinarians may provide useful evidence. This paper shows how a review of both human and animal literature can be used to design queries for syndromic surveillance systems.

Hantaviruses are globally distributed and cause severe human disease. Puumala hantavirus (PUUV) is the most common species in Northern Europe, and the only hantavirus confirmed to circulate in Sweden, restricted to the northern regions of the country. In this study, we aimed to further add to the natural ecology of PUUV in Sweden by investigating prevalence, and spatial and host species infection patterns. Specifically, we wanted to ascertain whether PUUV was present in the natural reservoir, the bank vole (Myodes glareolus) further south than Dalälven river, in south-central Sweden, and whether PUUV can be detected in other rodent species in addition to the natural reservoir. In total, 559 animals were collected at Grimsö (59°43′N; 15°28′E), Sala (59°55′N; 16°36′E) and Bogesund (59°24′N; 18°14′E) in south-central Sweden between May 2013 and November 2014. PUUV ELISA-reactive antibodies were found both in 2013 (22/295) and in 2014 (18/264), and nine samples were confirmed as PUUV-specific by focus reduction neutralization test. Most of the PUUV-specific samples were from the natural host, the bank vole, but also from other rodent hosts, indicating viral spill-over. Finally, we showed that PUUV is present in more highly populated central Sweden.

Tuberculosis (TB) in livestock, caused by Mycobacterium bovis, persists in many countries. In the UK and Ireland, efforts to control TB through culling of badgers (Meles meles), the principal wildlife host, have failed and there is significant interest in vaccination of badgers as an alternative or complementary strategy. Using a simulation model, we show that where TB is self-contained within the badger population and there are no external sources of infection, limited-duration vaccination at a high level of efficacy can reduce or even eradicate TB from the badger population. However, where sources of external infection persist, benefits in TB reduction in badgers can only be achieved by ongoing, annual vaccination. Vaccination is likely to be most effective as part of an integrated disease management strategy incorporating a number of different approaches across the entire host community.

Epidemiological studies use georeferenced health data to identify disease clusters but the accuracy of this georeferencing is obfuscated by incorrectly assigning the source of infection and by aggregating case data to larger geographical areas. Often, place of residence (residence) is used as a proxy for the source of infection (source) which may not be accurate. Using a 21-year dataset from South Australia of human infections with the mosquito-borne Ross River virus, we found that 37% of cases were believed to have been acquired away from home. We constructed two risk maps using age-standardized morbidity ratios (SMRs) calculated using residence and patient-reported source. Both maps confirm significant inter-suburb variation in SMRs. Areas frequently named as the source (but not residence) and the highest-risk suburbs both tend to be tourist locations with vector mosquito habitat, and camping or outdoor recreational opportunities. We suggest the highest-risk suburbs as places to focus on for disease control measures. We also use a novel application of ambient population data (LandScan) to improve the interpretation of these risk maps and propose how this approach can aid in implementing disease abatement measures on a smaller scale than for which disease data are available.

Salmonella typhimurium phage type DT 193 survived in small numbers, in stored static slurry derived from veal calves, for the 7-week period of observation. The viable coliform count fell by 1½ logs during the first 2 weeks of storage, thereafter there were only relatively small fluctuations in the coliform population. In all 735 of 752 Escherichia coli isolates examined from eight samples of slurry were resistant to 3–6 antibacterial drugs. There was no dramatic change in the overall level of drug resistance amongst the E. coli with time. Chloramphenicol resistance was recorded in 400 (55%) of the E. coli. It was always associated with multiple resistance, with 96% of the strains being resistant to 5 or 6 drugs, although the proportion of isolates of each of the ten most prevalent O-serotypes resistant to chloramphenicol was variable and ranged between none and 97·5%. The use of biotyping together with O-serotyping indicated that the E. coli population was extremely complex, although certain components of the population remained relatively stable within the dominant flora with time since several of the more common O-serotype/biotype combinations were isolated from more than half of the eight slurry samples examined.

Toxoplasmosis is a worldwide zoonotic infectious disease caused by Toxoplasma gondii. This infection is estimated to affect about a third of the world's population. The aim of this study was to evaluate the knowledge of Italian women about toxoplasmosis and its forms of transmission, clinical manifestations, diagnosis and prevention through two different modalities (e-research and traditional research). In a cross-sectional study, 808 Italian women were interviewed, using a self-administered questionnaire, through two different modalities: an e-research or web survey and a traditional paper research and 84% reported to have heard about toxoplasmosis, but from most of the sample, it resulted that the knowledge of the protozoan disease was superficial and incomplete.

The assessment of the dimensionality related to the toxoplasmosis knowledge's instrument showed that the scale is composed by two stable and reliable factors which explain 58.6% of the variance: (a) the basic knowledge (α = 0.83), which explains the 45.2% of the variance and (b) the specialist knowledge (α = 0.71), which explains the 13.4% of the variance. The variance and the multiple linear regression data analysis showed significant predictors of correct basic knowledge of toxoplasmosis: the highest age, the highest degree of study, to have previously contracted illness or to know someone who had contracted it, to be working or to be housewives. In conclusion, this study showed limited awareness of toxoplasmosis and suggested the implementation of effective education and learning programs. The results also showed that online data collection, in academic research, might be a valid alternative to more traditional (paper-and-pencil) surveys.

It is more than 25 years since the first case of AIDS was reported in the United Kingdom. In December 1981 a gay man was referred to a London hospital with opportunistic infections indicative of immunosuppression. National surveillance began the following year, in September 1982, with the notification of deaths and clinical reports of AIDS and Kaposi's sarcoma plus laboratory reports of opportunistic infections. Since then epidemiological surveillance systems have evolved, adapting to, and taking advantage of advances in treatments and laboratory techniques. The introduction of the HIV antibody test in 1984 led to the reporting of HIV-positive tests by laboratories and the establishment of an unlinked anonymous survey in 1990 measuring undiagnosed HIV infection among gay men attending sexual health clinics. The widespread use of highly active antiretroviral therapies (HAART) since 1996 has averted many deaths among HIV-positive gay men and has also resulted in a large reduction in AIDS cases. This led to a need for an enumeration of gay men with HIV accessing NHS treatment and care services (1995 onwards), more clinical information on HIV diagnoses for epidemiological surveillance (2000 onwards) and the routine monitoring of drug resistance (2001 onwards). Twenty-five years after the first case of AIDS was reported, gay and bisexual men remain the group at greatest risk of acquiring HIV in the United Kingdom. Latest estimates suggest that in 2004, 26 500 gay and bisexual men were living with HIV in the United Kingdom, a quarter of whom were undiagnosed. In this review, we examine how national surveillance systems have evolved over the past 25 years in response to the changing epidemiology of HIV/AIDS among gay and bisexual men in the United Kingdom as well as advances in laboratory techniques and medical treatments. We also reflect on how they will need to continue evolving to effectively inform health policy in the future.

We investigated faecal samples collected from the rectum of 518 cattle on 371 randomly selected smallholdings in Bangladesh for the presence of sorbitol non-fermenting (SN-F) shiga toxin-producing Escherichia coli (STEC). The SN-F isolates were tested for the presence of rfb O157, stx1, stx2, eae and hlyA genes by polymerase chain reaction (PCR). Seven SN-F isolates lacking these genes were profiled by pulsed-field gel electrophoresis (PFGE) to verify their clonality. SN-F E. coli was identified in 44 [8·5%, 95% confidence interval (CI) 6·4–11·2] samples; of these, 28 (5·4%, 95% CI 3·8–7·7) had shiga toxin-producing strains, although only two carried the rfb O157 gene. Thirteen isolates carried the hlyA gene while 18 harboured the eae gene. Based on PFGE, six pulsotypes were observed among the seven isolates that had no virulence genes. To the best of our knowledge this is the first report on shiga toxin-producing E. coli from direct rectal faecal samples of cattle on smallholdings.

Insights into transmission dynamics of enteropathogens in children attending daycare are limited. Here we aimed at identifying daycare centre (DCC) characteristics associated with time-clustered occurrence of enteropathogens in DCC-attending children. For this purpose, we used the KIzSS network, which comprises 43 DCCs that participated in infectious disease surveillance in The Netherlands during February 2010–February 2013. Space–time scan statistics were used to identify clusters of rotavirus, norovirus, astrovirus, Giardia lamblia and Cryptosporidium spp. in a two-dimensional DCC characteristic space constructed using canonical correlation analysis. Logistic regression models were then used to further identify DCC characteristics associated with increased or decreased odds for clustering of enteropathogens. Factors associated with increased odds for enteropathogen clustering in DCCs were having indoor/outdoor paddling pools or sandpits, owning animals, high numbers of attending children, and reporting outbreaks to local health authorities. Factors associated with decreased odds for enteropathogen clustering in DCCs were cleaning child potties in designated waste disposal stations, cleaning vomit with chlorine-based products, daily cleaning of toys, extra cleaning of toys during a suspected outbreak, and excluding children with gastroenteritis. These factors provide targets for reducing the burden of gastrointestinal morbidity associated with time-clustered occurrence of major enteropathogens in DCC attendees.

A cross-sectional study was carried out in injecting drug users (IDUs) from Greece to assess the seroprevalence of human herpesvirus 8 (HHV-8) and to identify potentially associated risk factors. A total of 288 IDUs were tested for K8.1 antibodies to HHV-8 lytic antigen. Associations between HHV-8 serostatus and potential risk factors were examined using univariate and multivariate logistic regression analysis. Seroprevalence of HHV-8 was 24·3% (95% CI 19·5–29·7), increasing with age from 19·4% in those aged <30 years to 52·9% in those aged ⩾40 years (P for trend=0·003). No statistically significant associations between HHV-8-positive status and gender, educational level, age at first drug injection, needle sharing, number of imprisonments, complications from drug overdose, HIV and HCV were observed. In the multivariate logistic regression analysis, older age (⩾40 vs. <40 years, OR 3·30, 95% CI 1·14–9·56) and report of septicaemia/abscess (yes vs. no, OR 1·80, 95% CI 1·01–3·18) were each independently associated with higher HHV-8 seroprevalence. HHV-8 is highly prevalent in the IDU population in Greece. The independent association between HHV-8 and reported abscess or septicaemia supports the hypothesis that poor hygiene conditions in the setting of drug injection may contribute to HHV-8 transmission.

An outbreak of infections due to multiple antibiotic-resistant bacteria took place over a period of approximately 18 months in a renal unit. Strains of Escherichia coli, Enterobacter aerogenes, Klebsiella pneumoniae, Citrobacter spp. and Pseudomonas spp. were involved, and a variety of antibiotic resistances was encountered. Closely related plasmids encoding resistance to aztreonam, ceftazidime and piperacillin, possibly derived from an archetypal plasmid of 105 kb were found in the majority of isolates examined. After limiting the use of aztreonam the incidence of new patient isolates of multiple-resistant organisms was greatly reduced. This study demonstrated how molecular studies can contribute to the control of an outbreak situation in a hospital unit by providing an impetus to reduce the use of specific antibiotics.

Non-typhoidal Salmonella (NTS) serovars, sequences types and antimicrobial susceptibility profiles have specific associations with animal and human infections in Vietnam. Antimicrobial resistance may have an effect on the manifestation of human NTS infections, with isolates from asymptomatic individuals being more susceptible to antimicrobials than those associated with animals and human diarrhoea.

The effect of long-term exposure to cigarette smoke on the height and specificity of the secondary humoral immune response to influenza was investigated in a murine model system. It was shown that if mice were pre-immunized with a sub-lethal infection of influenza virus and then exposed to cigarette smoke daily for 36 weeks, they were able to mount a secondary immune response of normal height on subsequent challenge with the homologous virus strain. The response, however, was less specific than that elicited in control mice, with high titres of cross-reacting antibody by haemagglutination-inhibition to the following strain in the same antigenic series. Recall of antibody to the previous strain in the antigenic series was not observed in either control or smoke-exposed animals. These results serve to correct an earlier discrepancy between the murine system and human studies in which the response to influenza infection in mice was depressed by prolonged exposure to cigarette smoke, whereas in man the response of smokers did not differ significantly from that of non-smokers. This apparent discrepancy had been caused by a lack of previous experience of influenza in the mice, which had therefore mounted a primary response, compared with the secondary response observed in the human studies.

Coxsackie A 6 virus, strain V 29, originally isolated from Aedes polynesiensis in Fiji, was found to survive in A. australis for 5 days after intrathoracic injection and for 6 days after feeding on viraemic mice, and in Culiseta tonnoiri for 8 days after feeding.

The virus level in both fed and injected mosquitoes fell steadily after infection and never exceeded the original level.

No virus transmission was obtained in 46 successful second feedings on days 10–14 with A. australis, but three transmissions were obtained with C. tonnoiri, two on day 10 and one on day 13, from 12 successful second feedings.

The incidence of infection by mycobacteria, other than tubercle bacilli (MOTT) is increasing in the United Kingdom, Europe and the United States. These diseases increase morbidity and are an increasing public health concern. However, the epidemiology of disease due to these species is not well characterized. We used space–time clustering approaches and Generalized Linear Modelling to investigate the potential predictors of disease in cases of infection by organisms of the Mycobacterium avium complex (MAC) and M. malmoense recorded in the north of England during 2000–2005. There was significant spatial and temporal clustering in juvenile cases of infection by MAC but not for cases of infection in adults by either species. There were no significant predictors of infection by M. malmoense or juvenile cases of M. avium. Incidence of disease caused by M. avium in adults was significantly related to health deprivation and weakly related to rainfall. We consider possible reasons for the difference in epidemiology in infection by M. avium in adults and juveniles.

HBsAg reappearance may constitute not only a risk for liver disease but also an infectious source. We aimed to determine whether HBsAg may reappear after spontaneous HBsAg seroclearance. A cohort of 2999 HBsAg-positive subjects aged 30–55 years was recruited in Guangxi, China in 2004. HBsAg was tested every 6 months from July 2004 to June 2007, then, one more time in December 2013. The results showed that spontaneous HBsAg seroclearance occurred in 41 subjects in the first 3 years, giving a 0·54% annual seroclearance rate. Thirteen of the 41 subjects were randomly tested for HBsAg in 2013. Four subjects became HBsAg positive. S gene sequences of HBV were analysed from serum collected before seroclearance and after reappearance, respectively, for subject QS840 (11 and 12 clones), subject TN98 (13 and 13 clones) and subject WX227 (10 and 8 clones). Serotype, subgenotype and amino-acid substitution pattern in each sample collected after reappearance was observed in the sample collected before HBsAg seroclearance. Nucleotide similarity between the two sequences from each subject was >99% and five sequences from subject TN98 were the same. In conclusion, following reactivation, HBsAg may reappear in individuals with spontaneous HBsAg seroclearance many years previously.

Varicella is a disease caused by varicella-zoster virus. It is transmitted via the respiratory route, is highly communicable and mainly affects young children. An effective vaccine is now available, whose routine use is advised by health authorities in the USA and which can prevent severe disease, although breakthrough infections do occur. In deciding whether or not to include a vaccine in the routine vaccination schedule, knowledge of the morbidity of the disease in question is fundamental. Although reporting of varicella is compulsory in Catalonia, doctors only have to report the weekly number of cases diagnosed, and not their age distribution. Given that recent data on the prevalence of the infection in Catalonia according to age groups is available, it was considered that, using these data, an estimation of age-related incidence could be made.

The objective of the present study was to estimate the incidence of varicella in Catalonia on the basis of the available seroprevalence data. A curve was fitted to the observed prevalence and point prevalence estimates for all ages were obtained. The incidence was derived by smoothed prevalence for each of these age groups. Estimated variance of the estimated incidence was obtained by the delta method. Predicted prevalence in the 0–4 years age group was calculated by the smoothed prevalence.

The model that best fitted the sample prevalence was the exponential function. The estimated number of varicella cases in this study was 46419 (95% CI 40507–52270). As the population in Catalonia in 1996 was 6090040, the previous results give an incidence rate of 762·2 per 100000 persons/year with their 95% CI (666·1–858·3).

The method described may be applied to the study of incidence rates in relation to the prevalence of diseases if we accept that the infection produces permanent immunity; the risk of mortality is the same for infected and non-infected subjects and that the disease incidence and population remain constant in time.