Infections caused by Vibrio vulnificus were first reported in 1979 by Blake et al. of the US Centers for Disease Control. At that time described as a ‘rare, unnamed halophilic lactose-fermenting Vibrio species’, V. vulnificus has emerged as the most virulent foodborne pathogen in the United States with a hospitalization rate of 0·910 and a case-fatality rate of 0·390. It is in addition a significant cause of potentially life-threatening wound infections. Infections following ingestion of raw or undercooked seafood, commonly raw oysters, can lead to a primary septicaemia with a fatality rate of 50–60%. An unusual symptom, occurring in 69% of 274 cases reviewed by Oliver, is the development of secondary lesions, typically on the extremities, which are generally severe (often a necrotizing fasciitis) and require tissue debridement or amputation. These cases occur almost exclusively in males over the age of 50 years. Interestingly, this gender specificity has been found to be due to the female hormone oestrogen, which in some manner provides protection against the lethal V. vulnificus endotoxin. Further, most cases occur in persons with certain underlying diseases which are either immunocompromising or which lead to elevated serum iron levels (e.g. liver cirrhosis, chronic hepatitis, haemochromatosis). V. vulnificus infections resulting in primary septicaemia have been extensively studied, and the subject of several reviews. This review concentrates on the wound infections caused by this marine bacterial pathogen, including the more recently described biotypes 2 and 3, with brief discussions of those caused by other marine vibrios, and the increasingly reported wound/skin infections caused by Mycobacterium marinum, Erysipelothrix rhusiopathiae, and Aeromonas hydrophila.

The aim was to establish the prevalence of large pericardial effusions in the Western Cape Province of South Africa, and to determine the incidence of various types of effusions. A total of 233 patients presented with large pericardial effusions. Each patient underwent tests for HIV, sputum smear and culture, blood culture, blood biochemistry and serological testing. Tuberculous pericardial effusions were diagnosed according to pre-determined criteria. Eighty-four patients (36·1%) were found to be HIV positive; 81 of these (96·4%) had tuberculous pericarditis. More than 65% of the study population was aged between 15 and 39 years. The prevalence of HIV amongst unemployed individuals was 49·0% compared to 30·0% amongst employed individuals. Tuberculous pericarditis was the most common cause of pericardial effusions (69·5%, n=162). It was concluded that tuberculosis (TB) is a leading cause of pericarditis in this province of South Africa. The prevalence of TB confounded by HIV co-infection is steadily increasing, burdening the health-care facilities.

To assess the sensitivity of the Swedish surveillance system, four notifiable communicable diseases in Sweden were examined during 1998–2002 with the two-sources capture–recapture method, based on parallel clinical and laboratory notifications. The sensitivity (proportion of diagnosed diseases actually being notified) was highest for salmonellosis (99·9%), followed by meningococcal infection (98·7%), and tularaemia (98·5%). For penicillin-resistant pneumococci, introduced as a notifiable disease in 1996, the overall sensitivity was 93·4% – increasing from 86·5% in 1998 to 98·5% in 2002. The system benefited from parallel reporting, with a sensitivity of clinical and laboratory notifications alone (all diseases combined) of 91·6% and 95·9% respectively. The sensitivity of both clinical and laboratory notifications was markedly higher in counties using the national electronic reporting system, SmiNet. Thus, sensitivity was higher for diseases with a long tradition of reporting, and there is a run-in period after a new disease becomes notifiable.

The space–time scan statistic is often used to identify incident disease clusters. We introduce a method to adjust for naturally occurring temporal trends or geographical patterns in illness. The space–time scan statistic was applied to reports of lower respiratory complaints in a large group practice. We compared its performance with unadjusted populations from: (1) the census, (2) group-practice membership counts, and on adjustments incorporating (3) day of week, month, and holidays; and (4) additionally, local history of illness. Using a nominal false detection rate of 5%, incident clusters during 1 year were identified on 26, 22, 4 and 2% of days for the four populations respectively. We show that it is important to account for naturally occurring temporal and geographic trends when using the space–time scan statistic for surveillance. The large number of days with clusters renders the census and membership approaches impractical for public health surveillance. The proposed adjustment allows practical surveillance.

In October 1998, cohorts of circular migrant men and their non-migrant sexual partners, and non-migrant men and their non-migrant sexual partners from rural South Africa were recruited and followed-up every 4 months until October 2001. At each visit, information on socio-demographic, sexual behaviour, sexually transmitted infections (STIs) and HIV was collected. In total, 553 individuals aged between 18 and 69 years were recruited. A man and his sexual partner(s) form a sexual partnership. Migration status, age, marital status, age at sexual debut, recent sexual partners and HIV status were found to be important determinants of STI. The risk of STI varies (σ2=1·45, P<0·001) significantly across sexual partnerships even after controlling for important determinants. The variance implies substantial correlation (0·59) between members of the same sexual partnership. Ignoring this correlation leads to incorrect inference. Migration contributes significantly to the spread of STIs. Community interventions of HIV/STI should target co-transmitter sexual partnerships rather than high-risk individuals.

Viral infections, especially those with noroviruses are the most common cause of acute gastroenteritis in Europe. To obtain information about the epidemic situation of noroviruses in Switzerland, an initial study was launched in the German-speaking part of the country to systematically compile Norovirus outbreak information between 2001 and 2003. In total, 73 outbreaks were registered. Most affected were closed settings, e.g. nursing homes (34%) and hospitals (25%). Transmission pathways were identified in 74% of Norovirus outbreaks. In 81% of these cases person-to-person transmission was the primary route of infection and on seven occasions (13%), a foodborne transmission was the possible cause. Furthermore, Norovirus outbreak characteristics of epidemiological importance are highlighted with a discussion of four selected events.

Escherichia coli O157 outbreaks were identified in Minnesota in February 2003 involving seven persons and in Colorado in July 2003 involving 13 persons. Case isolates from the two states had matching pulsed-field gel electrophoresis (PFGE) patterns. Independent case-control studies linked infections in each outbreak with eating alfalfa sprouts that were traced to the same seed distributor. The Colorado sprouter reportedly complied with the Food and Drug Administration (FDA) sprout guidance, whereas the Minnesota sprouter did not. These investigations revealed that increased compliance with existing FDA guidance is needed and that additional research is needed to improve the alfalfa seed decontamination process. This reaffirms the FDA recommendation that raw alfalfa sprouts should be considered potentially contaminated and avoided by persons at high-risk such as the elderly, young children, and immunocompromised persons. PFGE played an essential role in linking these two temporally and geographically distinct E. coli O157 outbreaks.

We investigate the epidemiology of 12 Verocytotoxin-producing Escherichia coli (VTEC) serogroups observed in a calf cohort on a Scottish beef farm. Fitting mathematical models to the observed time-course of infections reveals that there is significant calf-to-calf transmission of VTEC. Our models suggest that 40% of all detected infections are from calf-to-calf transmission and 60% from other sources. Variation in the rates at which infected animals recover from infection by different VTEC serogroups appears to be important. Two thirds of the observed VTEC serogroups are lost from infected calves within 1 day of infection, while the rest persist for more than 3 days. Our study has demonstrated that VTEC are transmissible between calves and are typically lost from infected animals in less than 1 week. We suggest that future field studies may wish to adopt a tighter sampling frame in order to detect all circulating VTEC serogroups in similar animal populations.

The aim of this study was to estimate transmission parameters of enterotoxigenic F4+ Escherichia coli F4 (F4+ E. coli) in groups of early weaned piglets with F4-receptor-positive (F4R+) and F4-receptor-negative piglets (F4R−). Transmission of F4+ E. coli was quantified in four heterogeneous groups of F4R+ and F4R− piglets. Infectiousness was determined by the number of F4+ E. coli/g faeces shed during 8 days. Transmission parameters were estimated using generalized linear models assuming a stochastic SIR model. F4R+ piglets were found to be more susceptible than F4R− piglets, but F4R+ and F4R− piglets were not different in infectiousness. The reproduction ratios for homogeneous F4R+ and F4R− populations were estimated as 6·37 (95% CI 1·89–21·48) and 0·02 (95% CI 0·00–1·13) respectively. The implication of these results is that in order to prevent major outbreaks, the fraction of F4R+ piglets should be small (approximately 10% or less). Therefore, selective breeding programmes could contribute to reducing F4+ E. coli-related diarrhoea and transmission.

This is a review of existing data on the burden of shigellosis in Thailand to determine trends, vulnerable groups, predominant species and serotypes, and antimicrobial resistance patterns. Diarrhoea and dysentery morbidity and mortality data from 1991 to 1999 was collected from the routine surveillance system and demographic data from the government census. International and local literature published between 1988 and 2000 was systematically reviewed. Based on the routine surveillance system, the annual incidence of bacillary dysentery decreased from 1·3 to 0·2/10000 persons per year. The remaining burden is highest in children <5 years of age at 2·7/10000 persons per year. In comparison, a prospective study utilizing active surveillance found an incidence in children <5 years of age that was more than 100-fold higher at 640/10000 persons per year. Despite the decrease in morbidity and mortality based on routinely collected data, shigellosis remains an important problem in children <5 years of age in Thailand.

The aim of this study was to establish the relative importance of various risk factors for toxoplasmosis in a United Kingdom antenatal population. Toxoplasma immune status was determined by an immunoassay and linked to a questionnaire exploring dietary and environmental exposure to toxoplasmosis. The overall seroprevalence found was 9·1% (172/1897). A significantly higher seroprevalence was associated with rural location of the childhood home, childhood home in Europe excluding the United Kingdom, feeding a dog raw meat and increased age. A non-significant higher prevalence of toxoplasmosis was observed in women who had lived with a cat or kitten as a child. In contrast to recent European studies only weak associations between diet and toxoplasmosis were found. Gardening activity was not associated with seropositivity but a non-significant lower seroprevalence was seen in gardeners who always wore gloves. This study confirms that toxoplasma prevalence in the United Kingdom has continued to decline since the 1960s. The increasing seroprevalence with age found in this study, highlights the continuing need to educate women of childbearing age about the risk factors for toxoplasmosis.

Congenital toxoplasmosis is rarely identified by routine clinical examination. The aim of this study was to estimate the incidence of the disease in the region of Ribeirão Preto, south-eastern Brazil. A definitive diagnosis was made on the basis of the persistence of anti-Toxoplasma IgG antibodies beyond 1 year of age. Blood samples obtained from 15162 neonates and adsorbed onto filter paper were tested for anti-Toxoplasma IgM antibodies. Fifteen samples gave positive results. A definitive diagnosis was confirmed in five of the 13 infants (38·5%) who completed follow-up. These five infants presented with serum IgM and/or IgA antibodies, and clinical abnormalities. Disease incidence was estimated to be 3·3/10000 (95% CI 1·0–7·7), indicating the need for preventive measures. Neonatal screening is feasible, but screening tests with a better performance are required; positive screening results must be carefully confirmed.

The frequency of meningitis due to penicillin-resistant Streptococcus pneumoniae (PRP) has increased in recent years, making treatment failure more likely. It is currently expected that pneumococcal conjugate vaccines might curb this trend. We investigated this issue using a mathematical model applied to the current prevalence of resistance and antibiotic exposure in the United States and in France. Our main finding was that the level of antibiotic exposure may limit the effect of the vaccine. In relatively low antibiotic exposure environments such as the United States, large-scale vaccination prevents a large part of PRP meningitis cases, whereas in high antibiotic-exposure environments such as France, vaccination alone does not lead to a substantial reduction in PRP meningitis incidence. Our results suggest that antibiotic exposure reduction will remain of primary importance for the control of PRP meningitis despite wide scale use of pneumococcal conjugate vaccines.

Serological and virological features of dengue fever (DF) and dengue haemorrhagic fever (DHF) in Thailand were analysed in 2715 patients from 1999 to 2002. The illness was caused by DEN-1 in 45%, DEN-2 in 32%, DEN-3 in 18% and DEN-4 in 5% of patients. Almost all of the DHF cases caused by DEN-2 and DEN-4 were in secondary infection, while approximately 20% of the DHF cases caused by DEN-1 and DEN-3 were in primary infection. Male[ratio ]female ratio and age distribution were not different among four serotypes in primary and secondary infections. These results indicate that DEN-1 and DEN-3 induce DHF in both primary and secondary infections, and suggest that DEN-2 and DEN-4 in Thailand are less likely to cause DHF in primary infections.

Hepatitis B virus (HBV) infection is endemic in Turkey, but the main routes of transmission were not well established. This study aims to detect the exposure time to HBV and associated risk factors among children. In a sampling group of chıldren aged 0–19 years living in Edirne, antiHBc, antiHBs and HBsAg were screened by the microELISA method. A questionnaire was also completed for each child. In 717 children that were included in the study, the total antiHBc seropositivity was 5·4% and was 1·8, 0·8, 1·7, 6·8, 11·8% in 0–1, 2–5, 6–10, 11–14, 15–19 years age groups respectively. The overall HBsAg seropositivity was 1·7%. The risk of HBV infection increased after the age of 10 years (OR 7·79, 95% CI 3·01–20·16). Collective circumcision was the only independent factor according to regression analysis. Children living in Edirne should be vaccinated against HBV before reaching 11 years of age.

Salivary excretion of rabies virus was evaluated in 14 adult vampire bats (Desmodus rotundus) intramuscularly injected with a large dose (106 MICLD50) of vampire rabies virus variant CASS88. Saliva samples were obtained from surviving bats every other day for 30 days, then weekly for 2 months, and finally 1 and 2 years later. Rabies virus was isolated in murine neuroblastoma cells and in randomly selected cases by PCR. Rabies virus was not detected in the saliva of any of the 11 animals that succumbed (somewhat early) to rabies challenge, nor in the control bats. In contrast, virus was detected early, and only once (days 6, 6 and 21) in each of the three animals that survived rabies challenge and remained healthy for at least 2 years after challenge. At that time even vigorous dexamethasone and cyclosporine administration failed to provoke further viral excretion.

In order to determine the susceptibility and serum neutralizing antibody response of Desmodus rotundus to rabies virus, bats were inoculated with a virus isolated from a naturally infected haematophagous bat. Bats were divided into four groups of 10 animals each. Dilutions of rabies virus containing 100, 1000, 10000 and 100000 MICLD50 (lethal dose 50% for mice inoculated by the intracerebral route) were administrated in the pectoral muscle. The presence of rabies virus was detected in brain and salivary glands by fluorescent antibody, mouse inoculation and RT–PCR. The observed mortality for each virus dose was 0, 20, 20 and 60% respectively. Serum neutralizing antibodies were tested for by the rapid fluorescent focus inhibition test, and antibody titres greater than 0·5 IU/ml were found in 53% of bats 30 days after virus inoculation. Resistance to infection was seen in bats that developed low or no detectable antibody response as well as in bats with high titres. Among the 10 bats that died of rabies, eight showed signs of paralytic rabies and two bats showed no clinical signs.

During the period 2000–2003, wild grey foxes (Urocyon cinereoargenteus) in northern Colombia became infected with rabies. In order to derive phylogenetic relationships between rabies viruses isolated in foxes, dogs and humans in this region, 902 nt cDNA fragments containing the G–L intergenic region and encoding the cytoplasmic domain of protein G and a fragment of protein L were obtained by RT–PCR, sequenced and compared. Phylogenetic analysis showed that rabies viruses isolated in foxes, dogs and humans belonged to a single genetic variant. Speculative analysis together with epidemiological data indicated that rabies in foxes may have been due to contact with rabid dogs. Rabies transmission between dogs, wild foxes and humans may happen in natural conditions in northern Colombia. This finding is the first to suggest dog-to-fox rabies transmission in South America, and provides another example of dog rabies variants being able to successfully colonize wildlife hosts.

Despite significant control efforts, foot-and-mouth disease (FMD) persists in Turkey, and new strains of serotypes A, O and Asia-1 are periodically reported to enter the country from the east. The status of FMD in Turkey is important regionally because the country forms a natural bridge between Asia where the disease is endemic, and Europe which has disease-free status. This study analysed spatial and temporal patterns of FMD occurrence in Turkey to explore factors associated with the disease's persistence and spread. Annual records of FMD distribution in Turkish provinces throughout 1990–2002, grouped by serotype (O, A and Asia 1), were analysed using geostatistical techniques to explore their spatial and temporal patterns. A meta-population model was used to test how disease status, expressed in terms of presence/absence, extinction, and colonization, and measured at the province level throughout the periods 1990–1996 and 1997–2002, could be predicted using province-level data on: ruminant livestock numbers; meat production-demand discrepancy (as a surrogate measure of animal and animal products marketing, i.e. long-distance contagion through the traffic of mainly live animals to urban centres); and the disease prevalence distribution as recorded for the previous year. A drastic overall reduction in FMD occurrence was observed from the period 1990–1996 to 1997–2002 when the disease was shown to retract into persistence islands. FMD occurrence was associated with host abundance, short distance contagion from adjacent provinces, and meat production-demand discrepancies. With FMD retracting into identified provinces, a shift in predictors of FMD occurrence was observed with a lower contribution of short-distance contagion, and a relatively higher association with meat production-demand discrepancies leading to live animal transport over long distances, and hence presenting opportunities for identifying critical-control points. The pattern of persistence differed according to serotype groups and is discussed in relation to their differential affinity to cattle and small ruminant hosts.

The occurrence of encephalomyocarditis virus (EMCV) among domestic pigs and wild boar in several European countries is described and discussed. From 1990 to 2001 clinical outbreaks were analysed and serum samples, partly from existing screening programmes, were tested for antibodies against EMCV. Most clinical EMCV outbreaks were reported in Belgium (320), followed by Italy (110), Greece (15) and Cyprus (6). The outbreaks appeared to be clustered in ‘endemic areas’ with an increase in outbreaks during the autumn and winter months. The within-herd seroprevalence measured in clinically affected pig farms varied considerably among farms (2–87%), with age (0–84%) and by country. Data from farms with no clinical disease showed that subclinical infection with EMCV was found both within (seroprevalence 6–62%) and outside (up to 17%) the endemic areas of the clinically affected countries as well as in the non-clinically affected countries Austria and France (3–5·4%). Among wild boar, the seroprevalence varied between 0·6 and 10·8%, and a study in Belgium found a prevalence of virus infection of 3·3%.