This study aimed to describe current epidemiological and clinical characteristics, medical follow-up and outcome in the real practice of acute hepatitis C (AHC) patients. AHC cases were retrospectively identified through the French Hepatology Reference Centres Surveillance system and additional data were collected. Sixty-one patients with AHC were identified (sex ratio: M/F 1·7/1; mean age 39 years). Forty-four (72%) had documented seroconversion within a 6-month period. Main reported risk exposures were intravenous or nasal drug use (35%), invasive medical procedures (25%) and sexual contact with a HCV-positive partner (20%). Spontaneous clearance of HCV RNA was observed in seven out of 16 patients followed without therapy. This study confirms the major role of drug use in HCV transmission and highlights the role of invasive medical procedures and occupational exposure.

To estimate incidence and completeness of notification of Legionnaires' disease (LD) in The Netherlands in 2000 and 2001, we performed a capture–recapture analysis using three registers: Notifications, Laboratory results and Hospital admissions. After record-linkage, 373 of the 780 LD patients identified were notified. Ascertained under-notification was 52·2%. Because of expected and observed regional differences in the incidence rate of LD, alternatively to conventional log-linear capture–recapture models, a covariate (region) capture–recapture model, not previously used for estimating infectious disease incidence, was specified and estimated 886 LD patients (95% confidence interval 827–1022). Estimated under-notification was 57·9%. Notified, ascertained and estimated average annual incidence rates of LD were 1·15, 2·42 and 2·77/100 000 inhabitants respectively, with the highest incidence in the southern region of The Netherlands. Covariate capture–recapture analysis acknowledging regional differences of LD incidence appears to reduce bias in the estimated national incidence rate.

Cattle are among the major reservoirs of Cryptosporidium parvum in nature. However, the relative contribution of C. parvum oocysts originating from cattle to human disease burden is difficult to assess, as various transmission pathways – including the human to human route – can co-occur. In this study, multilocus genotype richness of representative samples of human and bovine C. parvum are compared statistically using analytical rarefaction and non-parametric taxonomic richness estimators. Results suggest that in the time and space frames underlying the analysed data, humans were infected with significantly wider spectra of C. parvum genotypes than cattle, and consequently, a significant fraction of human infections may not have originated from the regional bovine reservoirs. This study provides statistical support to the emerging idea of the existence of distinct anthroponotic C. parvum cycles that do not involve cattle.

The KwaZulu Natal and Eastern Cape provinces of South Africa have experienced a serious dog rabies epidemic over the past three decades. Towards a better understanding of this epidemic, we have previously analysed nucleotide sequences of 142 rabies virus specimens that were obtained from these regions during 2003–2004 and provided a molecular description of the geographical distribution of rabies viral variants in the affected provinces. Here, as an extension, we studied five human cases that occurred during 2002–2003 and demonstrated the use of the sequence database in tracking unknown human rabies case histories. We were able to identify the geographical origin of viruses responsible for each human infection and in one case obtained evidence that suggested a non-bite transmission of rabies virus from an infected dog to a child. We argue for the value of this information in surveillance and epidemiological study and in the follow-up and management of potential exposures.

During 2004 and at the start of 2005 a university hospital in Southwest Germany was affected by an extensive outbreak of vancomycin-resistant Enterococcus faecium (VRE). Although the outbreak was contained, linezolid-resistant enterococci emerged during and after the outbreak as the usage of linezolid became more common. Linezolid resistance was no longer limited to VRE. Nosocomial spread of linezolid-resistant but vancomycin-susceptible E. faecium was detected and these strains also emerged in patients without prior drug exposure. Linezolid should therefore be used with caution and the susceptibility of isolates monitored over time. Isolation precautions and screening of contacts should be considered to avoid spread of resistant isolates.

A collection of 106 Neisseria gonorrhoeae ciprofloxacin-resistant isolates were typed using Neisseria gonorrhoeae multi-antigen sequence typing (NG-MAST). Opa-typing was performed on 74 isolates which had non-unique sequence types to determine if further discrimination could be achieved and if so whether this had any epidemiological basis. The 74 isolates were separated into 12 sequence types and 20 opa-types (OT). Seven opa-type clusters were congruent with the sequence types and five sequence types could be subdivided by opa-typing. These results demonstrate that opa-typing can add a further level of discrimination compared with NG-MAST. The surveillance data for isolates in the largest sequence type cluster (ST 147) indicated that two major subdivisions OT 1 and OT 2 differed epidemiologically by patients' sexual preference and geographical location. ST 147 is a common strain that has been isolated in several countries since 1999; our results suggest that it has diverged into at least two epidemiologically discrete forms.

Although Lyme borreliosis is increasingly diagnosed in the United Kingdom, few systematic studies have been performed there. UK data suggest that the commonest complications are neurological, but inadequate information exists about their nature and the incidence of late neuroborreliosis. Local data are necessary because clinical presentations may show geographical variation. This study aimed to provide data on clinical manifestations in an area of South West England and to estimate treatment delay. We reviewed clinical records of 88 patients in the Royal Devon and Exeter Hospital catchment area who had positive Borrelia antibody tests during a 5-year period. Fifty-six (64%) reported tick bites. The commonest presentations were erythema migrans (65%) and arthralgia/myalgia (27%). However, 22 patients (25%) had neurological symptoms other than headache alone. Fourteen had facial palsy, eight had confusion/drowsiness, four had meningism, five had radiculopathy, two had sixth nerve palsies, and two had peripheral neuropathies. No late, progressive or atypical neurological syndromes were found. Neurological manifestations were generally predictable and usually included either (or all) of meningoencephalitis, facial palsy or radiculopathy.

Using the enumeration district (ED) block level this study looked at the incidence of dengue fever and dengue haemorrhagic fever (DF/DHF) within the Songkhla municipality in Thailand. Each of the 146 blocks in this area were considered as study units and surveyed for their environmental characteristics. A total of 287 cases of DH/DHF occurring in the year 1998 were selected for this study and the location of their homes mapped. Clustering analysis showed point clustering of the homes (P<0·0001) which was probably due to high density habitation, without any actual prevalence of case clustering. There was no evidence of clustering of the ED blocks with an incidence of DF/DHF (P=0·32). DF/DHF incidence for each block was strongly associated with the percentages of shop-houses, brick-made houses and houses with poor garbage disposal (all P<0·01). DF/DHF control should be emphasized for the areas which have a predominance of these housing types.

Cat scratch disease (CSD), bacillary angiomatosis, hepatic peliosis and some cases of bacteraemia, endocarditis, and osteomyelitis are directly caused by some species of the genus Bartonella. The purpose of this study was to determine the prevalence of IgG antibodies against Bartonella henselae in healthy people and to identify the epidemiological factors involved. Serum samples from 218 patients were examined by indirect immunofluorescence assay (IFA). Significance levels for univariate statistical analysis were determined by the Mann–Whitney U test, χ2 test and Fisher's exact test. Of 218 patients, 99 were female and 119 male, with a median age of 34·36 years (range 0–91 years). Nineteen (8·7%) reacted with B. henselae antigens. Of all the factors concerning the seroprevalence rate being studied (age, sex, contact with animals, residential area), only age was statistically significant. Our serological data seems to indicate that B. henselae is present in Catalonia and could be transmitted to humans.

We investigated the identity of 37 Shigella flexneri strains that had previously been isolated from northern rural Vietnam (Son Tay Province) and described as untypable. Twenty-four isolates reacted with MASF 1c, a monoclonal antibody specific for S. flexneri serotype 1c. A further ten untypable isolates were found to be rough mutants (no longer expressing O-antigen) that were derived from serotype 1c strains. Pulsed-field gel electrophoresis demonstrated that these strains consisted of many different clones, indicating serotype 1c was well established in this region in the late 1990s. Serotype 1c was the most prevalent S. flexneri serotype isolated in the Son Tay Province, accounting for about 40% of S. flexneri isolates. Subsequent isolation of S. flexneri serotype 1c in this region and elsewhere in Vietnam confirmed that serotype 1c is of genuine importance in Vietnam.

Serological responses to Cryptosporidium-specific antigens (15/17 and 27 kDa) were compared among populations in four areas of the Czech Republic that use drinking water from clearly defined sources: (1) wells in a fractured sandstone aquifer, (2) riverbank infiltration, or (3) two different filtered and chlorinated surface waters. Among persons surveyed in the area with riverbank-infiltration water, 33% had a strong serological response to the 15/17-kDa antigen group whereas, in the other three areas, over 72% of persons had a strong response. These response differences suggest that Cryptosporidium exposures and infection were lower in the area with bank infiltration. The large percentage of the study population with a strong serological response to both antigens suggests high levels of previous infections that may have resulted in protective immunity for cryptosporidiosis. This may be one reason why no waterborne cryptosporidiosis outbreaks and few cases of cryptosporidiosis have been reported in the Czech Republic.

This study examined the ethnic difference in the association between increased serum ferritin (SF) (>300 μg/l) and acute inflammation (AI) (C-reactive protein ⩾1·0 mg/dl) between black and white males aged ⩾20 years. Using data from the third National Health and Nutrition Examination Survey (NHANES III), we determined the risk for having elevated SF in black males (n=164) and white males (n=325) with AI present as well as black males (n=1731) and white males (n=2877) with AI absent. Black subjects with AI present were 1·71 times (95% CI 1·18–2·49), and 1·87 times (95% CI 1·46–2·40) more likely to have increased SF than AI absent blacks and AI present whites, respectively. Furthermore, with AI present, every increment of C-reactive protein, white blood cell count, serum albumin, lymphocyte count and platelet count was associated with higher odds of having elevations in SF in blacks than whites. Regardless of AI status, blacks were more likely to have elevations in SF than whites, and the prevalence of elevated SF was significantly higher in blacks than whites. This finding suggested that black males may respond to inflammation with a more aggressive rise in SF compared to white males. Future research is needed to investigate the underlying mechanisms.

The aim of this study was to determine whether a temporary rise in sexual risk behaviour during war in Guinea–Bissau could explain the observed trends in HIV-1 and HIV-2 prevalence, and to explore the possible contribution of competitive elimination of HIV-2 by HIV-1. A simulation model of the heterosexual transmission of sexually transmitted infections was parameterized using demographic, behavioural and epidemiological data from rural Guinea–Bissau, and fitted to the observed HIV-1 and HIV-2 trends with and without a historic rise in risk behaviour. The observed trends could only be simulated by assuming a temporary rise in risk behaviour. Around 30% of the projected decline in HIV-2 prevalence from a peak of 8·7% to 4·3% in 2010 was due to competitive elimination by HIV-1. Importantly for public health, HIV-1 prevalence was predicted to continue increasing and to become the dominant HIV type by 2010. Data collection is required to validate this prediction.

The study was carried out in symptomatic and asymptomatic women attending peripheral health centres to determine the laboratory prevalence of sexually transmitted infection (STI), reproductive tract infection (RTI) and HIV. A total of 4090 women in four study groups were subjected to general and speculum examination and screened for aetiological agents of RTI/STI by standard laboratory techniques. The main complaint was vaginal discharge, singly (11·2%) or along with other symptoms (49·0%). Prevalence of RTI/STI/HIV infection was 36·8%. Agents of RTIs were harboured by 24·3% and that of STIs by 12·5%. HIV seroprevalence was very low (0·1%). HSV-2 represented the commonest aetiological agent of STIs, suggesting the necessity of including anti-HSV treatment in the national syndromic management guidelines. The present study highlights the importance of routine RTI/STI screening of antenatal mothers to avoid adverse consequences to the unborn child, and periodic surveys to detect the infection pattern in symptomatic and asymptomatic women, in order to control HIV infection.

The recent epidemic of chikungunya fever (2005–2006) in India has affected millions of people. The Andaman and Nicobar Islands, an archipelago situated in the Bay of Bengal 1200 km from peninsular India, also witnessed an outbreak of chikungunya fever starting in July 2006 which affected thousands of people. Chikungunya fever classically manifests as high fever, myalgia, arthralgia and arthritis and in a certain percentage of cases with maculopapular rashes. However, deviation from the classical clinical features of chikungunya fever was reported in the earlier and recent epidemics. During the recent epidemic in the Andaman and Nicobar Islands we came across ten cases of flaccid limb weakness following symptoms and signs suggestive of chikungunya fever. In four subjects we confirmed the diagnosis of chikungunya virus infection by serological method (IgM ELISA method). This is the case report of those four subjects.

This study examines a cohort of persons quarantined during the 2003 SARS outbreak in Canada and describes their understanding of, difficulties and compliance with, and the psychological impact of the quarantine experience. A mailed questionnaire was administered to 1912 eligible adults and included the Impact of Events Scale – Revised (IES-R) to assess symptoms of post-traumatic stress disorder (PTSD). Self-reported compliance with all required quarantine measures was low (15·8±2·3%), although significantly higher when the rationale for quarantine was understood (P=0·018). Health-care workers (HCW) experienced greater psychological distress, including symptoms of PTSD (P<0·001). Increasing perceived difficulty with compliance, HCW, longer quarantine and compliance with quarantine requirements were significant contributors to higher IES-R scores. The low compliance with quarantine requirements introduces concerns about the effectiveness of quarantine as a public health measure. Improvements in compliance and reduced psychological distress may be possible by minimizing duration, revising requirements, and providing enhanced education and support.

One of the areas most affected by SARS was Beijing with 2521 reported cases. We estimate the effective reproductive number Rt for the Beijing SARS epidemic, which represents the average number of secondary cases per primary case on each day of the epidemic and is therefore a measure of the underlying transmission dynamics. Our results provide a quantitative assessment of the effectiveness of public health control measures. More generally, our results illustrate how changes in Rt will reflect changes in the epidemic curve.

Attempts to explain the clear seasonality of rotavirus infections have been made by relating disease incidence to climate factors; however, few studies have disentangled the effects of weather from other factors that might cause seasonality. We investigated the relationships between hospital visits for rotavirus diarrhoea and temperature, humidity and river level, in Dhaka, Bangladesh, using time-series analysis adjusting for other confounding seasonal factors. There was strong evidence for an increase in rotavirus diarrhoea at high temperatures, by 40·2% for each 1°C increase above a threshold (29°C). Relative humidity had a linear inverse relationship with the number of cases of rotavirus diarrhoea. River level, above a threshold (4·8 m), was associated with an increase in cases of rotavirus diarrhoea, by 5·5% per 10-cm river-level rise. Our findings provide evidence that factors associated with high temperature, low humidity and high river-level increase the incidence of rotavirus diarrhoea in Dhaka.

Despite a significant public health burden the epidemiology of human Campylobacter infection remains blurred. The identification of demographic determinants for Campylobacter infection is therefore essential for identifying potential areas for intervention. Demographic data from an active, population-based sentinel surveillance system for Campylobacter infection (from 2000 until 2003, n=15 907) were compared with appropriate denominator data from the 2001 United Kingdom Census. Incidence was higher in males from birth until the late teens and in females from 20 to 36 years. Age- and gender-specific differences in Campylobacter incidence were observed in different ethnic and socioeconomic groups and hence are all major drivers for Campylobacter infection. Epidemiological studies on Campylobacter infection need to take these factors into consideration during design and analysis. The collation of detailed epidemiological data and its comparison with appropriate denominator data provides a valuable epidemiological tool for studying infection.