From 2000 to May 2004 there has been a marked increase in illness resulting from spore-forming bacteria in injecting heroin users in the United Kingdom. Clostridium novyi caused 63 cases of severe illness in 2000 and seven further cases from 2001. Wound botulism first occurred in 2000 (six cases) with 51 further cases to March 2004. Tetanus occurred in 20 cases between late 2003 and March 2004. Infections with C. histolyticum (nine cases), C. sordellii (one case) and Bacillus cereus (one case) were also reported. The reasons for the increase in illness are unclear. The major risk factor was skin- or muscle-popping. The problem appears to be here to stay. This review describes the causative organisms, pathogenesis, clinical presentation, epidemiology and treatment of cases. Clinical vigilance and a high standard of anaerobic microbiology are essential. Clinicians and laboratories must report such cases (or likely cases) rapidly so that clusters can be rapidly identified, in order to control disease. Prevention relies on tetanus immunization.

As a major foodborne pathogen, Campylobacter jejuni receives much attention in quantitative risk assessment. To date, all dose–response assessments have been based on a single human feeding study which unfortunately provides incomplete and possibly biased information on the dose–response relation. An incident at a dairy farm, where several children from a school class became ill as a result of drinking raw milk contaminated with C. jejuni, appeared to show a very clear dose–response relation between the amount of milk consumed and the attack rate. This relation was very nearly exponentially shaped and, therefore, seemed to conflict with the rather slowly rising dose–response relation established in the feeding study. Here we show that both datasets can be reconciled when illness and infection are considered separately. This not only provides new information on the illness dose–response relation for Campylobacter, but also amends the infection dose–response relation because of their conditional dependence.

In August 1998, an outbreak of campylobacteriosis occurred in one municipality in northern Finland. A 10% random sample of residents (population 15000) was selected through the National Population Registry for a survey conducted by using postal questionnaires. Cases were defined as residents of the municipality with onset of acute gastroenteritis from 1 to 20 August 1998. Of 1167 respondents (response rate 78%), 218 (18·7%) met the case definition. Drinking non-chlorinated municipal tap water was strongly associated with illness (OR 34·4). The estimated total number of ill persons was 2700. Campylobacter jejuni was isolated from stool samples of 45 (61%) out of 74 patients tested. All five isolates tested had indistinguishable PFGE patterns. Water samples were negative for campylobacter and coliforms. Epidemiological and environmental evidence suggested mains repair as the source of contamination. Non-chlorinated ground-water systems may be susceptible to contamination and can cause large outbreaks.

Wastewater treatment plant workers are exposed to microbes, including Salmonella, but the prevalence of antibodies against Salmonella species or serovars in their serum samples has not been studied. Antibodies against Salmonella Infantis and lipopolysaccharide antigen common to S. Enteritidis and S. Typhimurium in immunoglobulin classes IgA, IgM and IgG were measured from 79 serum samples of wastewater treatment plant workers and from 79 blood donor samples. Faecal samples for Salmonella and Campylobacter were studied. Gastrointestinal, dermal and other symptoms were compared between 81 wastewater treatment plant workers and 89 food-processing workers. The blood donors had more antibodies against all of the tested antigens expect for S. Infantis in IgM and IgA classes, even though the wastewater treatment plant workers had more gastrointestinal symptoms than the controls. No Salmonella or Campylobacter were found in any faecal samples. Salmonella is not a probable cause of symptoms among wastewater treatment plant workers.

The Japanese quarantine system monitors incoming passengers to detect imported pathogens at international airports. At one airport, we found that 74% of 13315 travellers returning with diarrhoea had visited only one country before entering Japan. On the basis of our results, we hypothesized that the international distribution and potential source of bacterial strains could be inferred by analysing strains isolated from travellers returning to Japan. In order to demonstrate the potential for this system, we randomly selected five Shigella sonnei strains and examined their restriction fragment length polymorphism patterns. One set of strains appeared to be closely related, while three sets, isolated from travellers who visited different countries were possibly related. These results suggest that international distributions and potential sources of S. sonnei may be inferred by monitoring isolates from passengers arriving at a Japanese quarantine station.

An investigation was conducted to determine the distribution, virulence gene profile and phenotypes of Shiga toxin-producing Escherichia coli (STEC) strains within a dairy farm in Kolkata, India by characterizing the STEC strains isolated from healthy dairy cow and calf stool samples, raw milk and farm floor swabs from July 2001 to March 2002. Primary screening by multiplex-PCR detected stx1 and stx2, the common virulence genes of STEC, in 18·9% of cow faeces, 32·4% of calf stool samples, 21·6% of farm floor swabs and 4·5% of raw milk samples and viable STEC were recovered from 4·5, 9·9, 8·1 and 1·8% of the corresponding PCR-positive samples. Strains harbouring stx1 (63·3%) and hlyA (53·3%) were frequently detected compared to eae (13·3%). Most of the strains harboured similar sets of reported virulence genes common among isolates from diarrhoea patients. Most of the strains also exhibited multidrug resistance, sorbitol fermentation and produced enterohaemolysin. The randomly amplified polymorphic DNA–PCR (RAPD–PCR) profile of the STEC strains isolated from the farm milieu revealed diverse banding patterns and clonal analysis demonstrated that the strains from different sources were not identical but showed some genetic relatedness. The study demonstrates the potential of dairy farm for housing virulent STEC.

We compared serotypes, drug susceptibility and presence of virulence-related genes in diarrhoeagenic Escherichia coli isolates from children <5 years from Kenya (n=82) and Japan (n=47). Multiplex PCR was used to detect genes coding for enteroaggregative adherence (aggR), heat-stable toxin (st), heat-labile toxin (lt), verotoxin (vt), attaching and effacing mechanism (eaeA), enteroaggregative E. coli heat-stable enterotoxin 1 (astA) and enteroinvasive mechanism (invE). Kenyan E. coli O-serotypes were more diverse than those from Japan (29 vs. 12 serotypes) and exhibited high level multidrug resistance to World Health Organization (WHO) recommended antibiotics. Resistance rates to tetracycline, ampicillin and sulphamethoxazole–trimethoprim were 70·7, 65·9 and 68·3% respectively, but resistance to sulphamethoxazole–trimethoprim among the E. coli isolates from Japan was low (2·1%). Kenyan isolates harboured virulence-related genes in high frequency (82·9%) compared to those from Japan (25·5%) with aggR and astA being the most frequently detected genes. The presence of multiple virulence genes was associated with multidrug resistance and this merits further investigation.

In 2001 Salmonella enterica serovar Typhimurium definitive phage-type (DT) 126 was isolated at higher frequency in Australia compared to other S. Typhimurium phage types and in comparison to previous years. Associated with this increase was the implication of this phage type in a number of food-related outbreaks. We compared fluorescent amplified fragment length polymorphism (FAFLP) to pulsed-field gel electrophoresis (PFGE), the current ‘gold standard’ for molecular typing of Salmonella for the discrimination between outbreak-associated isolates and epidemiologically unrelated DT126 strains. FAFLP showed a greater ability to discriminate between isolates than PFGE, with 16 groups of clusters or individual isolates with <90% similarity to each other compared to three groups as determined by PFGE. Both methods were able to discriminate between isolates from two separate outbreaks in South Australia and isolates associated with an outbreak at a restaurant in New South Wales. The resolving power of both methods was not sufficient to separate all epidemiologically unrelated DT126 isolates from the outbreak isolates. We conclude that amplified fragment length polymorphism is a useful tool to assist in the discrimination of S. Typhimurium DT126 isolates.

This study aimed to disentangle the independent contributions of Helicobacter pylori infections in mothers, fathers and siblings to the risk for the infection in the 11–13 years age group. Index children from a cross-sectional Stockholm school survey and their family members completed questionnaires and contributed blood samples. H. pylori serostatus was determined with an enzyme-linked immunosorbent assay and immunoblot. Fifty-four seropositive and 108 seronegative index children were included and 480 out of 548 family members contributed blood. In multivariate logistic regression modelling, having an infected mother (OR 11·6, 95% CI 2·0–67·9) or at least one infected sibling (OR 8·1, 95% CI 1·8–37·3) were risk factors for index child infection, whilst the influence of infected fathers was non-significant. Birth in high-prevalence countries was an independent risk factor (OR 10·4, 95% CI 3·4–31·3). H. pylori infections in mothers and siblings and birth in high-prevalence countries stand out as strong markers of infection risk amongst children in Sweden.

Orf of the hand is an uncommon zoonotic infection caused by a dermotropic DNA virus that belongs to the Parapoxvirus genus of the family Poxviridae. It is transmitted to humans through contact with infected sheep and goats and is reported as an occupational disease. We report nine cases of human orf seen in the hands of individuals, who were not occupationally exposed, after the feast of sacrifice in Turkey. Three cases were teachers and six out of the nine were housewives. We observed musculoskeletal complications and misdiagnoses. It is important to consider human orf in the differential diagnosis of hand lesions to prevent overtreatment and complications.

Phylogenetic relationships were examined for 70 Crimean-Congo haemorrhagic fever (CCHF) isolates from southern, central and West Africa, the Middle East and Greece using sequence data determined for a region of the S segment of the genome. Analysis revealed up to 18% genetic differences. Tree topology supports previous evidence for the existence of three groups of genetically related isolates, A, B and C. Within group A there are two clades: an African clade and a predominantly Asian clade comprising isolates from Pakistan, China, Iran, Russia and Madagascar. Group B includes isolates from southern and West Africa and Iran, and group C includes a single isolate from Greece. Despite the potential which exists for dispersal of the virus between Africa and Eurasia, it appears that circulation of the virus is largely compartmentalized within the two land masses, and the inference is that the geographic distribution of phylogenetic groups is related to the distribution and dispersal of tick vectors of the virus.

We did a seroepidemiological study to determine the circulating dengue virus serotypes and the extent to which the Singapore population has been exposed to multiple dengue virus serotypes, using the plaque reduction neutralization assay (PRNT). Of 164 enrolled subjects aged between 18–30 years, 49 subjects (29·8%) were PRNT positive for at least one dengue serotype. The seroprevalence was 39 (23·8%) for dengue virus serotype 1, 37 (22·6%) for type 2, 43 (26·2%) for type 3, and 30 (18·3%) for type 4. Of the 49 subjects with PRNT-positive dengue virus results, 28 (57·1%) were positive to all four virus serotypes, seven (14·3%) to three serotypes, two (4%) to two serotypes, and 12 (24·5%) to a single serotype. All four dengue virus serotypes circulate in Singapore, and a substantial proportion of the adult population in Singapore had exposure to more than one dengue virus serotype. In spite of multiple circulating types, the rate of dengue haemorrhagic fever is low in Singapore.

Of a total of 508 stool specimens from children with acute diarrhoea, mostly under the age of 5 years, collected in nine cities in the western and southeastern regions of Turkey between May 2000 and October 2002, 119 (23·4%) were found positive for rotaviruses (RV) by ELISA. Positive samples were characterized by electropherotyping and G and P genotyping. A subset of G and P types were confirmed by nucleic acid sequencing. The most prevalent types found in this collection included G4P[8], accounting for 27/64 (42·2%) of the fully characterized strains. G1P[8], G2P[4] and G3P[8] were found in 17 (26·6%), 2 (3·1%) and one (1·5%) samples respectively. Less common strains such as G9P[8] were found in two (3·2%) samples and G2P[8], G1P[6], G2P[6] and G4P[6], possible reassortant viruses, were found in five (7·8%), 2 (3·1%), one (1·5%) and four (6·3%) samples respectively. Mixed infections were found in six (7·3%) samples and were associated with combinations of G1+G2, G1+G4, G1+G9 and G4+G9 strains. This is the first molecular epidemiology study of its kind to be carried out in Turkey and suggests a significant diversity of co-circulating rotavirus strains.

We sought to determine the prevalence and associated characteristics of hepatitis A, B, C and D viruses and HIV infections in a prison in Durango, Mexico. Sera from 181 inmates were analysed for HAV antibody, hepatitis B core antibody (HBcAb), hepatitis B surface antigen (HBsAg), HCV antibody, HDV antibody, HIV antibody and HCV genotypes. Prevalence of HAV antibody, HBcAb, HBsAg, HCV antibody, HDV antibody and HIV antibody were 99·4, 4·4, 0·0, 10·0, 0·0 and 0·6% respectively. HCV genotype 1a predominated in HCV-infected inmates (62·5%), followed by HCV genotype 1b (25%) and HCV genotype 3 (12·5%). An association between HBV infection and age >30 years was found. HCV infection was associated with being born in Durango City, history of hepatitis, ear piercing, tattooing, drug abuse history, intravenous drug use and lack of condom use. We concluded that the prevalence of HAV, HBV, HDV and HIV infections in inmates in Durango, Mexico were comparable to those of the Mexican general population and blood donors, but lower than those reported in other prisons around the world. However, HCV infection in inmates was higher than that reported in Mexican blood donors but lower than those reported in other prisons of the world. These results have implications for the optimal planning of preventive and therapeutic measures.

We evaluated whether the increased immunogenicity provided by an MF59-adjuvant influenza vaccine translates into increased protection among the elderly. Residents of 25 long-term care facilities received either the adjuvant or a non-adjuvant vaccine. The odds ratios (OR) of influenza-like illness were calculated for non-adjuvant vs. adjuvant vaccine recipients, also stratifying for chronic cardiovascular, respiratory, and renal diseases. The risk was higher for the non-adjuvant vaccine recipients and highest for those with respiratory disease (OR 2·27, 95% CI 1·09–4·82) and cardiovascular disease (OR 1·88; 95% CI 1·31–2·72). In this study the MF59-adjuvant vaccine provided superior clinical protection among the elderly, especially those with chronic diseases.

During a 2-year period, blood samples from 2505 Lebanese blood donors were chosen at random, at various periods of time at one blood donation centre (Hotel Dieu de France, Beirut, Lebanon) and were screened for markers of HBV infection (HBsAg, anti-HBc and anti-HBs). The study showed HBsAg positivity of 0·6% and an overall exposure rate to HBV of 10·0%. Out of the 2505 blood donors screened, 56 (2·2%) were found to be ‘anti-HBc alone’ positive which is almost four times the HBsAg positivity. The 56 ‘anti-HBc alone’ samples were retested by another ELISA kit commercially available and 54 samples were ‘anti-HBc alone’ positive by both assays. The 54 samples had no serological markers as evidence of infection with human immunodeficiency virus (HIV) or hepatitis C virus (HCV). Only seven (13%) out of the 54 samples were HBV DNA positive by PCR and all were HBV genotype D. All seven HBV DNA-positive samples had HBV DNA levels below 400 copies/ml. Although any circulating HBV DNA among our ‘anti-HBc alone’ blood donors was below the detection limit of our Amplicor Monitor assay, some of these samples had circulating virus. A national study, where a larger number of blood donors from different blood donation centres across the country will perhaps determine whether screening for anti-HBc in addition to HBsAg detection is needed in Lebanese blood donors.

To control plagues of free-living mice (Mus domesticus) in Australia, a recombinant murine cytomegalovirus (MCMV) expressing fertility proteins is being developed as an immunocontraceptive agent. Real-time quantitative PCR was used to monitor the transmission of two genetically variable field strains of MCMV through mouse populations after 25% of founding mice were infected with the N1 strain, followed by the G4 strain 6 weeks later. Pathogen-free wild-derived mice were released into outdoor enclosures located in northwestern Victoria (Australia). Of those mice not originally inoculated with virus, N1 DNA was detected in more than 80% of founder mice and a third of their offspring and similarly, G4 DNA was detected in 13% of founder mice and in 3% of their offspring. Thus, prior immunity to N1 did not prevent transmission of G4. This result is promising for successful transmission of an immunocontraceptive vaccine through Australian mouse populations where MCMV infection is endemic.

A survey was carried out in two goat herds during a single peste des petits ruminant (PPR) outbreak. Clinical examination showed that animals belonging to the West African Dwarf species had severe symptoms while those belonging to the West African long-legged species had mild symptoms. To confirm and to monitor the disease in each species, the study required specific monoclonal antibody-based diagnostic tools. An association of shedding of PPR virus (PPRV) and acute or mild clinical signs of the disease could be demonstrated by the rinderpest virus (RPV)/PPRV immunocapture ELISA assay. Between 85 and 100% of nasal secretions obtained from clinically diseased goats during the PPR outbreak reacted positively. Parallel serological surveillance for specific measurement of PPR antibodies revealed that between 34·4 and 88·5% of animals with no detectable virus were, however, able to seroconvert and therefore seemed to demonstrate that PPR subclinical infections do occur. Antibodies were shown to impair the RP heterologous vaccination. This evaluation offers new prospects for diagnosis and management of PPRV infection as well as for RPV control.

A study was conducted to investigate the persistence of rabbit haemorrhagic disease virus (RHDV) in the environment. Virus was impregnated onto two carrier materials (cotton tape and bovine liver) and exposed to environmental conditions on pasture during autumn in New Zealand. Samples were collected after 1, 10, 44 and 91 days and the viability of the virus was determined by oral inoculation of susceptible 11- to 14-week-old New Zealand White rabbits. Evidence of RHDV infection was based on clinical and pathological signs and/or seroconversion to RHDV. Virus impregnated on cotton tape was viable at 10 days of exposure but not at 44 days, while in bovine liver it was still viable at 91 days. The results of this study suggest that RHDV in animal tissues such as rabbit carcasses can survive for at least 3 months in the field, while virus exposed directly to environmental conditions, such as dried excreted virus, is viable for a period of less than 1 month. Survival of RHDV in the tissues of dead animals could, therefore, provide a persistent reservoir of virus, which could initiate new outbreaks of disease after extended delays.

This study investigated whether exposure to inactivated rabbit haemorrhagic disease virus (RHDV) can produce an antigenic response in rabbits and protect them from a subsequent challenge with virulent virus. The aim was to determine if the spreading of baits containing RHDV, which is a common management practice in New Zealand to reduce rabbit numbers, could result in protective immunity in wild rabbits. RHDV was inactivated by ultraviolet (UV) light using an electronic UV crosslinker with a UV dose of 168·48 W-s/cm2 and a UV intensity of 0·0078 W/cm2. Two groups of four rabbits were then inoculated with inactivated virus via oral and intramuscular routes. Rabbits were monitored for 30 days post-inoculation and then challenged orally with virulent virus. No rabbit exposed to inactivated RHDV developed clinical signs of RHD or had antibodies at day 30 post-infection and all animals died within 82 h after challenge with virulent virus. No antibodies were detected at the time of death. These findings suggest that exposure to virus completely inactivated by UV light in the field or on baits will not protect rabbits against challenge with virulent virus.