This study reports on gastroenteritis outbreaks suspected of being norovirus infections in eight long-term care facilities. A descriptive epidemiological investigation was used to depict sources of infections and control measures. Outbreaks affected 299 (31%) of 954 residents and 95 (11%) of 843 staff. Attack rates were higher in residents (range 17–55%) than staff (range 3–35%). Person-to-person spread was suspected. The case-hospitalization rate was 2·5%, and no death occurred. Eight staff members were employed at multiple affected facilities and may have introduced disease into three facilities. Thirty-two stool specimens were positive for norovirus by real-time reverse transcriptase–polymerase chain reaction or enzyme immunoassay. Sequenced specimens were closely related to GII.4 New Orleans. A concurrent Clostridium difficile outbreak was also detected at one facility. Staff members who work at multiple facilities may transmit norovirus between them. Regulatory agencies should consider precluding ill staff from working in multiple facilities during outbreaks. Guidelines to control norovirus must be applied promptly and meticulously by facilities.

Making a distinction between facial palsy due to Lyme neuroborreliosis (LNB) and idiopathic facial palsy (IFP) is of importance to ensure timely and adequate treatment. The study objective was to assess incidence and patient characteristics of facial palsy due to LNB. Hospital records were reviewed of adult patients with facial palsy visiting the departments of neurology and/or otorhinolaryngology of Gelre hospitals between June 2007 and December 2017. Gelre hospitals are located in an area endemic for Lyme borreliosis. Patients with LNB had pleocytosis and intrathecal antibody production or pleocytosis with positive IgG serology. Patients with IFP had negative serology. Clinical characteristics were compared between patients with LNB and patients with IFP. Five hundred and fifty-nine patients presented with facial palsy, 4.7% (26) had LNB and 39.4% (220) IFP. The incidence of facial palsy due to LNB was 0.9/100 000 inhabitants/year. Over 70% of patients with facial palsy due to LNB did not report a recent tick bite and/or erythema migrans (EM). Patients with facial palsy due to LNB presented more often in July to September (69.2% vs. 21.9%, P < 0.001), and had more often headache (42.3% vs. 15.5%, P < 0.01). To reduce the risk of underdiagnosing LNB in an endemic area, we recommend testing for LNB in patients with facial palsy in summer months especially when presenting with headache, irrespective of a recent tick bite and/or EM.

Pulsed field gel electrophoresis (PFGE) of the genomic DNA of penicillin resistant serotype 19B Streptococcus pneumoniae was carried out. Thirteen strains form the Nagasaki area and 12 strains from other areas in Japan were examined. Twenty-three strains were resistant to erythromycin, tetracycline and trimethoprim/sulfamethoxazole but susceptible to chloramphenicol. Eight strains were resistant to ceftriaxone. All strains were multiply resistant. Five strains isolated from Nagasaki were indistinguishable from each other by using restriction enzymes Apa I and Sma I. Two strains isolated from other areas were indistinguishable from the above five strains. We could classify 13 Nagasaki strains into 3 groups and the total of 25 Japanese strains into 6 groups. These results suggest that the increasing prevalence of multiply drug resistant S. pneumoniae serotyped 19B in Japan is not due to a single clone, but at least one clone has spread widely in Japan.

Parainfluenza viruses were isolated 165 times during 14 years surveillance of the illnesses of a general practice population of around 3700. Type 1 isolations numbered 57, type 2 isolations 22 and type 3 isolations 86, representing annual rates of 33, 13 and 50 infections respectively per 10000 of population. Type 4 parainfluenza virus was not isolated. Three major classes of illness gave the following rates: sore throats (Throats) nine, acute febrile respiratory diseases (FRD) 23, acute non-febrile respiratory diseases (non-FRD) 71. The illnesses caused by the three types isolated were similar. Type 1 infections were most abundant in November and type 2 infections in December, and only 11.4 % of these types were isolated in the warm semester April through September. Type 3 infections were seasonally bi-modal, with a winter peak in January and an even greater prevalence (66% of the total) in the warm semester. Type 3 infections in the warmer months and in the later years of the Survey were usually more severe. Type 3 virus may therefore be heterogeneous, one subtype possessing and the other lacking the genetic mechanism of ‘cold-season’ prevalence. Geographical discontinuity between summer and winter isolations strengthens the case for the existence of the two subtypes of type 3 parainfluenza virus.

Type 3 infections caused the majority of the infections in very young infants. Type 2 infections were widely distributed at all ages. Females were attacked more often than males: type 1, 68.4%; type 2,636%; type 3, 53.5%. Type 3 infections in males outnumbered those in females up to 60 years of age, whereas female predominance became apparent in types 1 and 2 before 10 years of age.

All types were widely and sparsely distributed, areas of prevalence changing from year to year. Recurrences occurred only twice, both with type 3 infections. Six persons suffered both a type 1 and a type 3 infection, and one person suffered both a type 2 and a type 3 infection.

Population seroprevalence can be estimated from serosurveys by classifying quantitative measurements into positives (past infection/vaccinated) or negatives (susceptible) according to a fixed assay cut-off. The choice of assay cut-offs has a direct impact on seroprevalence estimates. A time-resolved fluorescence immunoassay (TRFIA) was used to test exposure to human parvovirus 4 (HP4). Seroprevalence estimates were obtained after applying the diagnostic assay cut-off under different scenarios using simulations. Alternative methods for estimating assay cut-offs were proposed based on mixture modelling with component distributions for the past infection/vaccinated and susceptible populations. Seroprevalence estimates were compared to those obtained directly from the data using mixture models. Simulation results showed that when there was good distinction between the underlying populations all methods gave seroprevalence estimates close to the true one. For high overlap between the underlying components, the diagnostic assay cut-off generally gave the most biased estimates. However, the mixture model methods also gave biased estimates which were a result of poor model fit. In conclusion, fixed cut-offs often produce biased estimates but they also have advantages compared to other methods such as mixture models. The bias can be reduced by using assay cut-offs estimated specifically for seroprevalence studies.

Respiratory syncytial virus (RSV) is the most common cause of documented viral respiratory infections, and the leading cause of hospitalization, in young children. We performed a retrospective time-series analysis of all patients aged <18 years with laboratory-confirmed RSV within a network of multiple affiliated academic medical institutions. Forecasting models of weekly RSV incidence for the local community, inpatient paediatric hospital and paediatric intensive-care unit (PICU) were created. Ninety-five percent confidence intervals calculated around our models' 2-week forecasts were accurate to ±9·3, ±7·5 and ±1·5 cases/week for the local community, inpatient hospital and PICU, respectively. Our results suggest that time-series models may be useful tools in forecasting the burden of RSV infection at the local and institutional levels, helping communities and institutions to optimize distribution of resources based on the changing burden and severity of illness in their respective communities.

Outpatient parenteral antimicrobial therapy (OPAT) programmes facilitate hospital discharge, but patients remain at risk of complications and consequent healthcare utilisation (HCU). Here we elucidated the incidence of and risk factors associated with HCU in OPAT patients. This was a retrospective, single-centre, case–control study of adult patients discharged on OPAT. Cases (n = 63) and controls (n = 126) were patients that did or did not utilise the healthcare system within 60 days. Characteristics associated with HCU in bivariate analysis (P ≤ 0.2) were included in a multivariable logistic regression model. Variables were retained in the final model if they were independently (P < 0.05) associated with 60-day HCU. Among all study patients, the mean age was 55 ± 16, 65% were men, and wound infection (22%) and cellulitis (14%) were common diagnoses. The cumulative incidence of 60-day unplanned HCU was 27% with a disproportionately higher incidence in the first 30 days (21%). A statin at discharge (adjusted odds ratios (aOR) 0.23, 95% confidence intervals (CIs) 0.09–0.57), number of prior admissions in past 12 months (aOR 1.48, 95% CIs 1.05–2.10), and a sepsis diagnosis (aOR 4.62, 95% CIs 1.23–17.3) were independently associated with HCU. HCU was most commonly due to non-infection related complications (44%) and worsening primary infection (31%). There are multiple risk factors for HCU in OPAT patients, and formal OPAT clinics may help to risk stratify and target the highest risk groups.

As the COVID-19 pandemic continues to escalate and place pressure on hospital system resources, a proper screening and risk stratification score is essential. We aimed to develop a risk score to identify patients with increased risk of COVID-19, allowing proper identification and allocation of limited resources. A retrospective study was conducted of 338 patients who were admitted to the hospital from the emergency room to regular floors and tested for COVID-19 at an acute care hospital in the Metropolitan Washington D.C. area. The dataset was split into development and validation sets with a ratio of 6:4. Demographics, presenting symptoms, sick contact, triage vital signs, initial laboratory and chest X-ray results were analysed to develop a prediction model for COVID-19 diagnosis. Multivariable logistic regression was performed in a stepwise fashion to develop a prediction model, and a scoring system was created based on the coefficients of the final model. Among 338 patients admitted to the hospital from the emergency room, 136 (40.2%) patients tested positive for COVID-19 and 202 (59.8%) patients tested negative. Sick contact with suspected or confirmed COVID-19 case (3 points), nursing facility residence (3 points), constitutional symptom (1 point), respiratory symptom (1 point), gastrointestinal symptom (1 point), obesity (1 point), hypoxia at triage (1 point) and leucocytosis (−1 point) were included in the prediction score. A risk score for COVID-19 diagnosis achieved area under the receiver operating characteristic curve of 0.87 (95% confidence interval (CI) 0.82–0.92) in the development dataset and 0.85 (95% CI 0.78–0.92) in the validation dataset. A risk prediction score for COVID-19 can be used as a supplemental tool to assist clinical decision to triage, test and quarantine patients admitted to the hospital from the emergency room.

This paper examines the sensitivity and specificity of two ELISA assays for IgM antibodies to Mycobacterium leprae, one employing natural phenolic glycolipid and the other employing a synthetic disaccharide glycoconjugate as antigen. Estimates of sensitivity and specificity are derived, based on a panel of sera from leprosy cases in Malawi and various non-leprosy controls from the UK. Though both assays were able to identify a high proportion of multibacillary patients, neither was able to detect a high proportion of paucibacillary patients without considerable loss of specificity. The implications of the inverse relationship between sensitivity and specificity are discussed with reference to the predictive value of such tests in such areas as Malawi, where the large majority of cases are paucibacillary.

Human immunodeficiency virus-1 (HIV-1) is characterised by a vast genetic diversity classified into distinct phylogenetic strains and recombinant forms. We describe the HIV-1 molecular epidemiology and evolution of 129 consecutive HIV-1 positive migrants living in Milan (northern Italy). Polymerase gene sequences of 116 HIV-1 subtype-B positive patients were aligned with HIV-1 reference sequences (https://www.ncbi.nlm.nih.gov/) by using MAFFT alignment and edited by using Bioedit software. A maximum likelihood (ML) phylogenetic tree was performed by MEGA7 and was visualised by using FigTree v1.4.3. Of 129 migrants, 35 were born in Europe (28 in Eastern Europe), 70 in the Americas (67 in South America), 15 in Africa and nine in Asia; 76.4% were men who have sex with men (MSM). The serotype HIV-1-B prevailed (89.9%), followed by -C, -F1, -D and -A. Compared with 116 HIV-B patients, the 13 with HIV-non-B showed lower Nadir of CD4+ cell/mmc (P = 0.043), more frequently had sub Saharan origin (38.5 vs. 1.72%, P = 0.0001) and less frequently were MSM (40 vs. 74.5%, P = 0.02). The ML phylogenetic tree of the 116 HIV-1 subtype-B positive patients showed 13 statistically supported nodes (bootstrap > 70%). Most of the sequences included in these nodes have been isolated from male patients from the Americas and the most common risk factor was MSM. The low number of HIV-1 non-B subtype patients did not allow to perform this analysis. These results suggest a shift of HIV-1 prevention projects' focus and a continuous monitoring of HIV-1 molecular epidemiology among entry populations. Prevention efforts based on HIV molecular epidemiology may improve public health surveillance setting.

The phenotypic and genotypic profiles of the V. cholerae strains causing the Mozambican 1997–8 epidemic were characterized to provide a reference for comparison with other epidemic strains. A total of 75 strains of V. cholerae O1 isolated in different provinces, were analysed. Strains were characterized by PCR for detecting toxin genes (ctxA, zot and ace), virulence associated genes (tcpA, nanH, hlyA and toxR) and ERIC sequences. All V. cholerae strains were serotype O1, Ogawa, biotype El Tor. MIC testing showed a high proportion of strains multi-resistant to drugs (100% to cotrimoxazole and 52% to tetracycline) and susceptibility to ciprofloxacin. The isolates contained two intact copies of the CTX genetic element and all other genes tested. PCR of restricted DNA revealed two ERIC types: the first in provincial isolates, also predominant in other African epidemic strains, and the second in Maputo isolates (the national capital).

Due to the poor positive predictive value of nucleic acid amplification tests (NAATs) for gonorrhoea when applied to a low-prevalence setting, current guidelines recommend the use of supplementary polymerase chain reaction (PCR) targeting a different gene for confirmation of true positives in urogenital specimens. This study sought to standardize and evaluate performance of an in-house opa gene-based PCR assay for gonorrhoea compared to assays targeting the porA pseudogene and 16S rRNA gene. Four hundred samples (300 endocervical, 100 urethral swabs) from patients attending STD clinics in New Delhi, India were used. The sensitivity, specificity, positive predictive value and negative predictive value of the opa-based PCR were 100%, 97·9%, 89·5% and 100%, respectively. In females, the use of NAATs provided enhanced diagnosis of gonorrhoea.

Tularemia has sustained seroprevalence in Eurasia, with estimates as high as 15% in endemic regions. The purpose of this report is to characterise the current epidemiology of Francisella tularensis subspecies holarctica in Georgia. Three surveillance activities are summarised: (1) acute infections captured in Georgia's notifiable disease surveillance system, (2) infectious disease seroprevalence study of military volunteers, and (3) a study of seroprevalence and risk factors in endemic regions. Descriptive analyses of demographic, exposure and clinical factors were conducted for the surveillance studies; bivariate analyses were computed to identify risk factors of seropositivity using likelihood ratio χ2 tests or Fisher's exact tests. Of the 19 incident cases reported between 2014 and August 2017, 10 were confirmed and nine met the presumptive definition; the estimated annual incidence was 0.12/100 000. The first cases of tularemia in Western Georgia were reported. Seroprevalences of antibodies for F. tularensis were 2.0% for military volunteers and 5.0% for residents in endemic regions. Exposures correlated with seropositivity included work with hay and contact with multiple types of animals. Seroprevalence studies conducted periodically may enhance our understanding of tularemia in countries with dramatically underestimated incidence rates.

In 1990, to study regional prevalences and risk factors of Helicobacter pylori infection in healthy young adult males, sera were collected from a nationwide sample of 1659 males (mean age 20·7 years) at introduction into the Air Force School for military students in Caserta, Italy. An enzyme-linked immunosorbent assay was used to detect H. pylori specific immunoglobulin G antibodies. The observed overall seropositivity rate was 17·5% (95% CI 15·7–19·4). Prevalence was higher in southern Italy and in the Italian islands as compared with northern Italy and central Italy (21·3% vs. 9·5%). Multiple logistic regression analysis showed that residence in southern areas and islands was the strongest predictor of the likelihood of H. pylori seropositivity; number of siblings in the household was marginally associated; years of father's schooling was not a significant predictor. H. pylori positive subjects were more likely positive for antibodies to hepatitis A virus infection (anti-HAV) than those H. pylori negative (35·4% vs. 24·9%; Odds Ratio 1·7, 95% CI 1·3–2·2). Adjustment for the confounding effect of sociodemographic variables weakened this association (OR 1·3, 95% CI 1·0–1·7). These findings suggest that differences in environmental conditions rather than in socioeconomic status may have played the major role in the different spread of H. pylori infection across the country.

Isolation rates in Canada of Salmonella enterica serovar Typhi increased from 0·29 to 0·55 isolations/100 000 population during 2000–2006. Although no ciprofloxacin resistance was detected, nalidixic acid resistance increased from 41% to 80%. Multidrug-resistant S. Typhi represented 18% of the strains tested. Pulsed-field gel electrophoresis (PFGE) analysis of 222 isolates resulted in 91 distinct patterns clustering into four major genetic similarity groups. The five most frequently occurring PFGE patterns accounted for 46% of the isolates. Drug-resistant isolates predominantly occurred in one PFGE similarity group. There were 39 phage types identified in 826 isolates analysed with 60% described by five phage types; 134 were untypable. The phage types associated with multidrug resistance were phage types 53, B1, D1, E1, E9, G3 and M1. Improved integration of epidemiological and laboratory case data will facilitate the protection of public health in Canada during an era of increasing travel and globalization.

1. The paper records the result of a study of the serological types of haemolytic streptococci in scarlatina, puerperal fever, erysipelas, ear infections, tonsillitis, erythemas, etc., and normal throats, and their epidemiological relationships.

2. Tables and charts are given showing statistical records of scarlatinal cases which occurred over a period of 16 months in Edinburgh, a city with a population of about half a million inhabitants. In all there were 2287 cases. Of these 2169 were treated in an infectious diseases hospital, and were thus readily accessible for investigation. 1364 of the cases were school children. The strains of haemolytic streptococci from 1664 of the hospital-treated cases were serologically examined.

3. During an epidemic of scarlatina certain schools practically escaped, but in these there was a proportionately greater number of cases the following year, as compared with those schools which had suffered heavily the previous season.

4. Depending on the types of haemolytic fltreptococci isolated, scarlatina patients have been divided into three main categories: (1) pupils or school children, (2) “pupil-contacts” (families of pupils), and (3) “non-pupil-contacts” (famines without children of school age). The types of haemolytic streptococci found in these three groups have been correlated. There was a similarity in the types found in pupils and “pupil-contacts”, but not in those of pupils and “non-pupil-contacts”. Those types obtained from “pupil-contacts” and “non-pupil-contacts” were related. These features have been discussed.

5. Certain types of haemolytic streptococci predominated in the pupil cases. These were for the most part the epidemic types. The non-epidemic types, sporadic in appearance, were found mostly in “non-pupil-contacts”. “Pupil-contacts” occupied an intermediate position.

6. One main epidemic type ran through the three classes of patients. It was later replaced by another type.

7. The majority of cases of scarlatina which occurred in a school at a particular time were due to one type. It tended to persist despite the sporadic occurrence of other types. On occasions two types were present concurrently, but usually the one disappeared, and afterwards the other produced most of the cases.

8. The types of haemolytic streptococci in scarlatina, erysipelas, otitis media and mastoiditis, tonsillitis, and other streptococcal infections have been compared and the findings discussed. For the most part there was a correlation of types among all these conditions, and these types appeared to be responsible for a single epidemic of streptococcal infections.

9. The major epidemic types found simultaneously in the City of Edinburgh and in a small community, 12 miles distant, differed.

10. The types of haemolytic streptococci isolated from the throats of nurses in a general hospital bore little relationship to those isolated from medical officers and nurses in an infectious diseases hospital. The common epidemic types were present in the latter.

11. Correlations were shown to exist between the types of haemolytic streptococci in scarlatina patients, and those isolated from various members of their families, in 50% of the occasions in which the organisms were found.

12. The rapid change in the types occurring in the nasopharynx and the problem of immunity have been investigated and discussed in the case of a person exposed to massive infections with haemolytic streptococci.

13. Haemolytic streptococci on the handkerchiefs of scarlatina patients were viable after 4 weeks in most cases and after 7 weeks in two cases. After 15 weeks they were all dead.

14. Haemolytic streptococci were isolated from toys and fruit taken from scarlatina patients.

Penicillin-resistant Streptococcus pneumoniae (PRSP) is widespread all over the world, including countries previously free of PRSP. This study was undertaken to determine the prevalence, the common serotypes and the clonality of PRSP isolated over a period of 1 year, from various clinical samples from three major hospitals in Kuwait. Strains were identified by standard methods and their antibiotic susceptibility was determined by the agar dilution method. The clonality of the isolates was determined by repetitive extragenic palindromic sequence–polymerase chain reaction (REP–PCR) genomic profiling and pulsed field gel electrophoresis (PFGE). Serotyping was done by Quellung reaction using specific antisera. We found that 55% of the S. pneumoniae were resistant to penicillin (46% and 9% exhibited intermediate and full resistance, respectively). Nearly 41% were resistant to sulfamethoxazole-trimethoprim, 9% to cefotaxime and ceftriaxone, 15% to amoxycillin-clavulanate, 17% to cefuroxime, 77% to cefaclor, and 14% to clindamycin. The commonest serotypes among the PRSPs were 6A, 6B, 14, 19F, 23F and nontypable. PFGE and REP–PCR patterns showed a large diversity of genetic clones of the PRSP. Serotypes 6B, 14, 19F and 23F were more clonally related than the others. Our data showed that the prevalence of PRSP was high, the serotypes were diversified and different genetic clones make up the population of circulating PRSP in Kuwait.

Twelve grade school and junior high school students had oral exposures to hepatitis B surface antigen (HBsAg) positive saliva via contact with contaminated musical instruments. The 12 exposed students and 18 students who served as age and sex matched controls were tested for the presence of HBsAg and antibody to the hepatitis surface antigen (anti-HBs) at 2 weeks, 8 weeks and 6 months after exposure. All students were negative for HBsAg and anti-HBs on all dates tested and reported no illness during that time suggestive of viral hepatitis. There was no evidence of viral hepatitis, type B transmission from the exposure. The students probably experienced the maximum possible oral exposure from direct or fomites contact, since there was no cleaning of the musical instruments between use by the students and teacher. Based on these results, the risk of transmission of viral hepatitis, type B from oral contact with fomites is unlikely.

Commercially available kits for detection of hepatitis B surface antigen (HBsAg) and hepatitis B surface antibody (anti-HBs) by enzyme immunoassay (EIA) were evaluated in American Samoa during a public health programme to eliminate the transmission of hepatitis B. The first 19184 serum specimens obtained, representing 68% of the total cooperating population, were initially tested for anti-HBs, and those without detectable antibody were tested for HBsAg. All the antigen-positive serum samples, and a selection of the antigen-and antibody-negative specimens were tested by radioimmunoassay (RIA) for detection of both markers. Compared with the standard tests, the EIA kits for anti-HBs and HBsAg performed well; sensitivity and specificity were 90·3 and 96·0%, respectively, for antibody, and 97·8 and 97·9% respectively for antigen. Substantial disagreement between the EIA and RIA tests for HBsAg was found only for specimens considered weakly reactive by EIA. Few differences were found between three EIA method options for follow-up HBsAg testing of weakly reactive serum specimens; each option contributed about equally to improved test specificity for these ‘borderline’ specimens. Based on their demonstrated equivalence to the standard RIA tests, we conclude that the EIA kits for anti-HBs and HBsAg detection are suitable for use in hepatitis B control programmes in open populations.

Cerebral toxoplasmosis is a leading cause of the central nervous system disorders in acquired immune deficiency syndrome. This study aimed to investigate the clinical course of cerebral toxoplasmosis in human immunodeficiency virus (HIV)-infected individuals. The study included 90 HIV-infected patients with cerebral toxoplasmosis, who underwent inpatient treatment. In case of positive enzyme immunoassay, HIV infection was confirmed with the immunoblot test. The HIV-1 ribonucleic acid level was determined using the polymerase chain reaction method. The flow cytometry was used for counting CD4 (cluster of differentiation 4 cells). Pathomorphological examination included the autopsy, gross and microscopic examination of internal organs, histological and other methods. The incidence of cerebral toxoplasmosis significantly increases at the CD4 count below 100 cells/μl, P < 0.001, and at the HIV viral load above 50 copies/ml, P < 0.05. The clinical picture of cerebral toxoplasmosis included focal symptoms, cognitive impairment, toxic syndrome, mild cerebral symptoms and a meningeal symptom. Given the absence of a specific clinical picture and the absence of abnormal laboratory and instrumental findings, the cerebral toxoplasmosis needs to be diagnosed with a number diagnostic methods combined: clinical examination, laboratory testing, immunological examination, molecular genetic testing and neuroradiological imaging.