A surveillance system to assess the impact and changing epidemiology of invasive meningococcal disease in Europe was set up in 1987. Since about 1991, contributors from national reference laboratories, national communicable disease surveillance centres and institutes of public health in 35 European countries provided information on all reported cases of meningococcal disease in their country. We describe some trends observed over the period 1993–6. The main findings were: the overall incidence of meningococcal disease was 1·1 per 100000 population but there was some evidence of a slow increase over time and with northern European countries tending to have a higher incidence (Kendall correlation 0·5772, P<0·001), an increasing predominance of serogroup C, and a shift in the age distribution towards teenagers and away from younger children (χ2 test for trend 44·56, P<0·0001), although about half of the cases were under 5 years of age. The overall case fatality rate was 8·3% and the most common serosubtypes were B[ratio ]15[ratio ]P1.7,16 and C[ratio ]2a[ratio ]P1.2,5.

In this 1 year cross-sectional study of personnel being discharged from compulsory military service, an available database of health-related information was used to examine the association of meningococcal carriage with socio-demographic factors. A representative, systematic sample of 1632 personnel was interviewed and had throat cultures taken. The overall meningococcal carriage rate was 16%. Serogroups B and Y accounted for 76% and 13% of the isolates respectively. In univariate analysis, carriage was associated with male gender (P<0·0001), <12 years school education (P=0·002), smoking (P=0·014), and service at a ‘closed’ base, reflecting greater interpersonal contact (P<0·0001). In multivariate analysis, only service on a closed base and male gender retained significance. School education of <12 years remained significant for females only. Variables not associated with carriage included number of siblings, intensity of smoking, and use of the contraceptive pill. In this setting, meningococcal carriage was associated with the type of base on which soldiers served; and smoking was not an independent risk factor for carriage.

Lack of reliable data about street vendors, who are difficult to survey, has hampered efforts to improve the safety of street-vended food. A two-phase method for sampling vendors, surveying first in areas of concentrated vending activity identified by local authorities and second in randomly selected areas, was developed and implemented in two Guatemalan cities where street-vended food had been implicated in cholera transmission. In a 4-day survey in Escuintla, 59 vendors (42 from phase 1, 17 from phase 2) were interviewed. They demonstrated good knowledge of food safety and cholera but unsafe practices, implying that more effective, practical training was needed. In a 6-day survey in Guatemala City, 78 vendors (77 from phase 1, 1 from phase 2) were interviewed. Sixty-eight (87%) vendors stored water, usually in wide-mouthed vessels prone to contamination; this led to a field test of a new system for safe water storage. Useful information for public health planning and intervention can be gathered rapidly with this new method for surveying street vendors.

Protein A of Staphylococcus aureus contains a polymorphic Xr-region characterized by a tandem repeat of eight amino acid units. In this study, the diversity of genes encoding the repeat regions and their relatedness among S. aureus strains was analyzed. Ten different protein-A types characterized by repeat numbers 4–13 were identified in a total of 293 clinical isolates. The protein-A type with 10 repeat units (10 repeats) in the Xr-region was most frequently detected in methicillin-resistant S. aureus, whereas the majority of methicillin- susceptible strains were distributed almost evenly into protein-A types with 7–11 repeats. Strains that belonged to a single coagulase type were classified into multiple protein-A types, e.g. strains with the common coagulase types II and VII were differentiated into 7 and 8 protein-A types, respectively.

Nucleotide sequence analysis of the Xr-region of 42 representative strains revealed the presence of 37 different genotypes (spa types), which were constituted by a combination of several of 24 different repeat unit genotypes. Based on the similarity in arrangement of repeat unit genotypes, 34 strains with different repeat numbers were classified into 5 genetic clusters (C1–C5). The clusters C1, C2 and C3 consisted exclusively of strains with identical coagulase types II, III, and IV, respectively. These findings suggested that the protein-A gene of S. aureus has evolved from a common ancestral clone in individual clusters independently.

Pulsed field gel electrophoresis (PFGE) of the genomic DNA of Moraxella catarrhalis was done in 172 strains isolated from sputum of patients with respiratory infections in Nagasaki (130 strains), Europe (14 strains), Thailand (6 strains), Uganda (3 strains), Bangladesh (5 strains) and Kuwait (14 strains). Restriction endonuclease with SmaI generated 4–16 DNA fragments ranging from 1000 kb to 24·25 kb and was classified into 31 major groups. It was found that there were wide variations of DNA restriction patterns of strains isolated from the same and different geographical areas. DNA restriction patterns of strains isolated in Nagasaki during the last 12 years showed dynamic changes of the predominant strains in each time period. We conclude from this study that PFGE is a suitable method to document interstrain variation in M. catarrhalis.

We present data on pneumococcal isolates collected from deep and superficial sites over a 16-year period at the Edinburgh City Hospital. The 10 most frequent serotypes overall were 6, 19, 11, 9, 3, 14, 1, 15 and 18 in children and 19, 23, 6, 6, 9, 11, 3, 15, 14, 22 and 4 in adults. Over 88% (2588/2932, 88·3%) of these pneumococci were of serotypes represented in the 23-valent polysaccharide pneumococcal vaccine. Within the 20–45 years age group, 228/434 (52·5%) of specimens were from HIV-infected individuals. The isolations showed a seasonal distribution with peaks in February and troughs in September. The annual numbers of blood culture isolates showed an upward trend. Recurrent isolations were more frequent in HIV-infected individuals (49/132, 37%) than in non-HIV-infected individuals (218/2421, 9·9%) (relative risk = 5·05, 95% confidence interval, 3·46–7·03). The prevalence of resistance to penicillin and erythromycin was lower than that reported in other parts of the UK.

Reports of increasing incidence and severity of invasive group A streptococcal (GAS) infections come mainly from affluent populations where exposure to GAS is relatively infrequent. We conducted a 6-year retrospective review of GAS bacteraemia in the Northern Territory of Australia, comparing the Aboriginal population (24% of the study population), who have high rates of other streptococcal infections and sequelae, to the non-Aboriginal population. Of 72 episodes, 44 (61%) were in Aboriginal patients. All 12 cases in children were Aboriginal. Risk factors were implicated in 82% of episodes (91% in adults) and there was no significant difference in the proportion of Aboriginal compared to non-Aboriginal patients with at least one risk factor. Genetic typing of isolates revealed no dominant strains and no evidence of a clone which has been a common cause of these infections elsewhere.

The Andaman islands were known to be endemic for leptospirosis during the early part of the century. Later, for about six decades no information about the status of the disease in these islands was available. In the late 1980s leptospirosis reappeared among the settler population and several outbreaks have been reported with high case fatality rates. Besides settlers, these islands are the home of six primitive tribes of which two are still hostile. These tribes have ample exposure to environment conducive for transmission of leptospirosis. Since no information about the level of endemicity of the disease among the tribes is available, a seroprevalence study was carried out among all the accessible tribes of the islands. A total of 1557 serum samples from four of the tribes were collected and examined for presence of antileptospiral antibodies using Microscopic Agglutination Test (MAT) employing 10 serogroups as antigens. An overall seropositivity rate of 19·1% was observed with the highest rate of 53·5% among the Shompens. The seropositivity rates in the other tribes were 16·4% among Nicobarese, 22·2% among the Onges and 14·8% among the Great Andamanese. All of the tribes except the Onges showed a similar pattern of change in the seroprevalence rates with age. The prevalence rates were rising from low values among children to reach a peak in those aged 21–40 years and then declined. Among Onges the seroprevalence rates continued to rise beyond 40 years. In all the tribes, seroprevalence rates were found to be significantly higher among the males. The commonest serogroups encountered were Australis followed by Grippotyphosa, Icterohaemorrhagiae, Pomona and Canicola.

Sharps injuries are a major cause of transmission of hepatitis B and C viruses and human immunodeficiency virus in health-care workers. To determine the yearly incidence and causes of sharps injuries in health-care workers in Taiwan, we conducted a questionnaire survey in a total of 8645 health care workers, including physicians, nurses, laboratory technicians, and cleaners, from teaching hospitals of various sizes. The reported incidence of needlestick and other sharps injuries was 1·30 and 1·21 per person in the past 12 months, respectively. Of most recent episodes of needlestick/sharps injury, 52·0% were caused by ordinary syringe needles, usually in the patient units. The most frequently reported circumstances of needlestick were recapping of needles, and those of sharps injuries were opening of ampoules/vials. Of needles which stuck the health-care workers, 54·8% had been used in patients, 8·2% of whom were known to have hepatitis B or C, syphilis, or human immunodeficiency virus infection. Sharps injuries in health-care workers in Taiwan occur more frequently than generally thought and risks of contracting blood-borne infectious diseases as a result are very high.

Aboriginal communities in Northern Australia with high rates of group A streptococcal (GAS) skin infection in childhood also have high rates of renal failure in adult life. In a cross-sectional study of one such high risk community, albuminuria was used as a marker of renal disease. The prevalence of albuminuria increased from 0/52 in subjects aged 10–19 years to 10/29 (32·9%) in those aged 50 or more (P<0·001). Antibodies to streptococcal M protein, markers of past GAS infection, were present in 48/52 (92%) at ages 10–19 years, 16/32 (50%) at ages 30–39, and 20/29 (69%) in those aged 50 or more. After allowing for the age-dependencies of albuminuria and of M protein antibodies (P<0·001) albuminuria was significantly associated with M protein antibodies (P<0·01). Thus, 72% of adults aged 30 or more with M protein antibodies also had albuminuria, compared with only 21% of those who were seronegative. More detailed modelling suggested that although most Aboriginal people in this community developed M protein antibodies following GAS infection in childhood, the development of proteinuria was associated with the persistence of such seropositivity into adult life. The models predicted that proteinuria developed at a mean age of 30 years in seropositive persons, at 45 years in seronegative persons who were overweight, and at 62 years in seronegative persons of normal weight. We demonstrated a clear association between evidence of childhood GAS infection and individual risk of proteinuria in adult life. This study provided a strong rationale for prevention of renal disease through the more effective control of GAS skin infections in childhood and through the prevention of obesity in adult life.

The objective was to assess the potential bias in unlinked anonymous HIV-seroprevalence surveys from objections to specimens being included. Objection rates in seroprevalence surveys were examined. Statistically large clusters of objections were considered to be the result of health care worker behaviour, and were disregarded. Underlying objection rates were estimated from remaining data and compared to seroprevalence. Overall objection rates approached or exceeded seroprevalence in many participating centres. However, underlying objection rates declined with time while prevalences were generally unchanging. Also, underlying rates correlated poorly with observed seroprevalences. Findings were therefore consistent with processes producing the clusters of objections and underlying objection rates independently of serostatus of individuals. Although national seroprevalence estimates produced by the surveys are reasonably free from objection bias, regional seroprevalence estimates outside London remain vulnerable to bias as a result of some centres returning data whose quality cannot be guaranteed.

During a 1-year period from October 1995 to September 1996, 273 isolations of Streptococcus pneumoniae were made from various types of clinical specimens. The majority of the isolates (39·2%) were from sputum whilst 27·5% were from blood, CSF and other body fluids. The organism was isolated from patients of all age groups, 31·1% from children aged 10 years and below, 64·7% of which come from children aged 2 years or below. The majority of the isolates belong to serotypes 1, 6B, 19B, 19F and 23F. Serotypes 1 and 19B were the most common serotypes associated with invasive infection. About 71·9% of the invasive infections were due to serotypes included in the available 23 valent polysaccharide vaccine. The rates of resistance to penicillin and erythromycin were 7·0 and 1·1% respectively. Our findings show that the serotypes of S. pneumoniae causing most invasive infections in Malaysia are similar to those in other parts of the world and the available vaccine may have a useful role in this population.

The prevalence of antibodies against Lyme disease spirochaetes in serum samples from 80 forestry workers at high occupational risk of Lyme disease was surveyed by enzyme-linked immunosorbent assay (ELISA) with the OspC-I synthetic peptide. The peptide is part of the outer surface protein C (OspC) amino acid sequence located in the region conserved among Borrelia burgdorferi sensu stricto or sensu lato. Positivity for antibodies against OspC-I was observed in 25 (31·3%) of the forestry workers. Of these positive cases, 12 (15·0%) and 19 (23·8%) were positive for immunoglobulin M (IgM) and IgG antibody, respectively. Among 62 workers who were negative for IgG antibody against B. garinii or B. japonica in our previous study, 9 (14·5%) and 4 (6·5%) were positive for IgM and IgG antibody, respectively, in OspC-I ELISA. These results demonstrate for the first time that Lyme disease in forestry workers can be revealed using OspC-I ELISA. We conclude that forestry workers who show positive results for antibodies against OspC-I have very likely been exposed to Lyme disease spirochaetes, and that those who show positivity for IgM antibody against OspC-I may be in the early stage of Lyme disease.

Mycobacterium avium complex (MAC) is ubiquitous throughout the world. It is an opportunistic pathogen in AIDS patients but the number of cases in HIV negative patients is also increasing. The aim of this study was to determine whether patients were being infected with different MAC strains or whether one strain was dominant. DNA obtained from isolates in Brazil and England were compared using pulsed field gel electrophoresis (PFGE). Strains from 22 Brazilian patients clustered into 7 groups but 68/90 patients had a unique strain. In all patients, Brazilian and English, the same strain was isolated repeatedly over time, some over several years. This study shows that it is most likely that Man is infected from the environment and that one strain can survive without change for many years both in the environment and in Man.

This study was conducted to evaluate factors affecting the levels of total IgG (tIgG) and measles specific IgG (mIgG) in mother and cord sera, and the efficiency of transplacental transport of tIgG and mIgG. The study was conducted in four hospitals in Oporto, Portugal, where 1539 women and their newborns were enrolled. Measles IgG levels were lower among vaccinated mothers and respective cord sera than among vaccinated counterparts. Cord mIgG was strongly correlated with maternal levels in both vaccinated and unvaccinated groups. Transplacental transport efficiency (TTE) of mIgG decreased with increasing maternal levels, although almost one third of the observed effect was due to measurement error. The TTE was not affected by vaccination status. Monitoring maternal measles antibody levels and maternal vaccination status could be useful to determine when the age for measles vaccination can be reduced.

A novel water quality intervention that consists of point-of-use water disinfection, safe storage and community education was field tested in Bolivia. A total of 127 households in two periurban communities were randomized into intervention and control groups, surveyed and the intervention was distributed. Monthly water quality testing and weekly diarrhoea surveillance were conducted. Over a 5-month period, intervention households had 44% fewer diarrhoea episodes than control households (P=0·002). Infants <1 year old (P=0·05) and children 5–14 years old (P=0·01) in intervention households had significantly less diarrhoea than control children. Campylobacter was less commonly isolated from intervention than control patients (P=0·02). Stored water in intervention households was less contaminated with Escherichia coli than stored water in control households (P<0·0001). Intervention households exhibited less E. coli contamination of stored water and less diarrhoea than control households. This promising new strategy may have broad applicability for waterborne disease prevention.

In 1996, three adenovirus type 7 (Ad7) strains were isolated from children with fever and upper respiratory diseases in Japan. Restriction endonucleases (REs) analysis and PCR amplification of the E3 7·7 kDa ORF revealed that these strains were genotype Ad7h and closely related to an Argentine Ad7h strain, which has been reported to be highly virulent and so far predominant only in South America. These strains showed weak cross-neutralizing activity and specific haemagglutination-inhibition activity to Ad3 antiserum. The present findings suggest that Ad7h in South America has spread to other parts of the world. Since the seroprevalence to Ad7 in the current Japanese population is very low due to the absence of Ad7 circulation in Japan for decades, Ad7 outbreak as a typical case of re-emerging infectious diseases is a cause for serious concern.

From September 1991–January 1992, there was a measles epidemic in an established refugee camp for 7000 Vietnamese ‘Boat People’ living in Hong Kong. This 16 week outbreak occurred against a backdrop of poor uptake of measles vaccination and overcrowded living conditions. Two hundred and sixty-two children were affected (155 boys, 107 girls); 235 children (89·7%) were <2 years old, age range 5–39 months. Children age 6–11 months had the highest crude attack rate (AR) of 54·3%. The highest age specific crude AR was 83·8% in children aged 14 months. Measles complications affected 234 (89·3%) children. Sixty-six children (25·2%) were admitted to hospital. There were two deaths from pneumonia, giving a case fatality rate of 0·76%. Measles control in refugee camps continues to be a public health challenge.

The mode of spread of Helicobacter pylori infection is subject to ongoing debate. Recent studies among patients with gastrointestinal disorders suggest a potential role of conjugal transmission. In this study, the clustering of H. pylori infection was assessed among 110 employees of a health insurance company and their partners. Active infection with H. pylori was measured by the 13C-urea breath test. Information on potential confounders was collected by a standardized questionnaire. Overall, 16 employees (14·5%) and 24 partners (21·8%) were infected. While only 7% (6/86) of employees with an uninfected partner were infected, this applied to 42% (10/24) of employees with an infected partner. A very strong relation between partners' infection status persisted after control for age and other potential confounders (adjusted odds ratio, 7·0; 95% confidence interval, 1·8–26·7). Furthermore, the risk of infection increased with the number of years lived with an infected partner. These results support the hypothesis of a major role of spouse-to-spouse transmission of H. pylori infection.

The capture–recapture method was used to estimate the sensitivity of case finding in two national STD surveillance systems: (1) STD registration at municipal health services (STD-MHS); (2) statutory notification by clinicians (NNS). To identify those cases common to both surveillance systems, cases from 1995 were compared using individual identifiers. Estimated sensitivities for syphilis were: STD-MHS 31% (95% CI: 27–35%), NNS 64% (56–71%); and for gonorrhoea: STD-MHS 15% (14–18%), NNS 22% (19–25%). The combined sensitivity of both systems was 76% for syphilis and 34% for gonorrhoea. Differences in the sensitivity of the systems were significant. The NNS was more sensitive than the STD-MHS, and the identification of cases was significantly more sensitive for syphilis than for gonorrhoea. A stratified analysis showed comparable results for the two sexes. Knowledge on the sensitivity of surveillance systems is useful for public health decisions and essential for international comparisons.