Likely Route Of Infection Research Articles

The incidence of HIV-2 infection in Spain is declining – a registry data analysis

ObjectivesHIV-2 infection is a neglected disease caused by a human retrovirus that causes AIDS more slowly than HIV-1. Infection with HIV-2 is endemic in West Africa. Given its differential features, guidelines recommend ruling out HIV-2 infection in all newly diagnosed HIV-seropositive individuals. MethodsA national registry of HIV-2 cases was created in Spain in 1989, following the first report of three HIV-2+ individuals in Barcelona. The main demographics, clinical, and virological data are reported up to December 2023. ResultsA total of 424 individuals with HIV-2 infection were recorded in the Spanish registry. After a peak in 2009 when 31 cases were reported, new HIV-2 diagnoses steadily decreased. Less than 10 cases/year have been notified since the COVID-19 pandemic. In 2023, only eight cases were reported.Mean age at HIV-2 diagnosis was 44 years old, ranging from birth to 83 years. A total of 265 (62.5%) were male. Migrants predominated, being 322 (76%) Sub-Saharan Africans; however, 60 (14.2%) were native Spaniards. Heterosexual exposure was the most likely route of infection in at least 287 (67.7%) cases. A few cases could be traced to transfusions (n = 4), vertical infection (n = 2), or injection drug use (n = 7). In addition, 15 individuals (3.5%) were men who had sex with men. Coinfection with HIV-1 was recognized in 39 (9.2%) individuals. Molecular characterization of HIV-2 subtypes was performed in 139 individuals, 121 being infected with subtype A and 18 with subtype B. ConclusionThe annual incidence of HIV-2 infection in Spain has decreased after peaking 15 years ago, being the current number of cases below 10 per year. Three-quarters are African migrants, and two-thirds are male. Circulation of HIV-2 in Spain is limited and steadily decreasing.

Neurological signs in lambs as indication for BVDV circulation in a cattle young stock rearing herd

AbstractTwin lambs, born on a farm where cattle young stock and sheep were raised together in the same barn, presented with neurological signs. As border disease could not be ruled out, samples were sent for diagnostic testing and subsequent sequence comparison to identify potential infection with sheep or cattle pestiviruses. The 5′UTR polymerase chain reaction (PCR) confirmed that both lambs and one calf were infected with a bovine viral diarrhoea virus (BVDV) 1b strain. Additional analysis of the E2 and NS5b PCR products demonstrated a ∼100% sequence identity for 5′UTR, E2, and NS5b. Viral transmission from a persistently infected (PI) calf to the sheep dam during pregnancy was considered the most likely route of infection. In spite of the advice to separate and slaughter the lambs, as they could act as a source of infection to the rest of the sheep and cattle, they remained in the flock. Over time they overcame the clinical signs and were slaughtered at the end of the season. This case demonstrates that sheep can be infected with BVDV. Neurological signs and other health problems in sheep could indicate a BVDV infection in both sheep and cattle when reared in close contact.

Yersiniosis in New Zealand.

The rate of yersiniosis in New Zealand (NZ) is high compared with other developed countries, and rates have been increasing over recent years. Typically, >99% of human cases in NZ are attributed to Yersinia enterocolitica (YE), although in 2014, a large outbreak of 220 cases was caused by Yersinia pseudotuberculosis. Up until 2012, the most common NZ strain was YE biotype 4. The emergent strain since this time is YE biotype 2/3 serotype O:9. The pathogenic potential of some YE biotypes remains unclear. Most human cases of yersiniosis are considered sporadic without an identifiable source. Key restrictions in previous investigations included insufficient sensitivity for the isolation of Yersinia spp. from foods, although foodborne transmission is the most likely route of infection. In NZ, YE has been isolated from a variety of sick and healthy domestic and farm animals but the pathways from zoonotic reservoir to human remain unproven. Whole-genome sequencing provides unprecedented discriminatory power for typing Yersinia and is now being applied to NZ epidemiological investigations. A “One-Health” approach is necessary to elucidate the routes of transmission of Yersinia and consequently inform targeted interventions for the prevention and management of yersiniosis in NZ

Peripheral immune response in the African green monkey model following Nipah-Malaysia virus exposure by intermediate-size particle aerosol.

The ability to appropriately mimic human disease is critical for using animal models as a tool for understanding virus pathogenesis. In the case of Nipah virus (NiV), infection of humans appears to occur either through inhalation, contact with or consumption of infected material. In two of these circumstances, respiratory or sinusoidal exposure represents a likely route of infection. In this study, intermediate-size aerosol particles (~7 μm) of NiV-Malaysia were used to mimic potential routes of exposure by focusing viral deposition in the upper respiratory tract. Our previous report showed this route of exposure extended the disease course and a single animal survived the infection. Here, analysis of the peripheral immune response found minimal evidence of systemic inflammation and depletion of B cells during acute disease. However, the animal that survived infection developed an early IgM response with rapid development of neutralizing antibodies that likely afforded protection. The increase in NiV-specific antibodies correlated with an expansion of the B cell population in the survivor. Cell-mediated immunity was not clearly apparent in animals that succumbed during the acute phase of disease. However, CD4+ and CD8+ effector memory cells increased in the survivor with correlating increases in cytokines and chemokines associated with cell-mediated immunity. Interestingly, kinetic changes of the CD4+ and CD8bright T cell populations over the course of acute disease were opposite from animals that succumbed to infection. In addition, increases in NK cells and basophils during convalescence of the surviving animal were also evident, with viral antigen found in NK cells. These data suggest that a systemic inflammatory response and “cytokine storm” are not major contributors to NiV-Malaysia pathogenesis in the AGM model using this exposure route. Further, these data demonstrate that regulation of cell-mediated immunity, in addition to rapid production of NiV specific antibodies, may be critical for surviving NiV infection.

Horizontal transmission of Endolimax piscium, causative agent of systemic amoebiasis in Senegalese sole Solea senegalensis.

Systemic amoebiasis of Senegalese sole Solea senegalensis is caused by Endolimax piscium Constenla, Padrós & Palenzuela, 2014 a cryptic parasitic member of the Archamoebae whose epidemiology is yet unknown. To test whether the parasite can be transmitted horizontally, an experimental trial by cohabitation between non-infected and infected fish was designed. Transmission of the parasite from naturally infected to healthy fish was confirmed in the experiment, with the water as the most likely route of infection. Under the conditions of the study, the infection process was remarkably slow, as parasites could be detected by in situ hybridization within the intestinal mucosa of recipient fish only after 17 wk of cohabitation, and none of the new hosts displayed clinical signs of disease. Long prepatent period and the need for additional triggering factors for the development of the clinical condition are suggested. The intestinal mucosa is proposed as the tissue where the amoeba can survive as endocommensal, but also as an invasion route from which the parasite would disperse to other organs.

Melioidosis in a patient with type 1 diabetes mellitus on an insulin pump.

SummaryDiabetes mellitus is a well-recognised risk factor for melioidosis, the disease caused by Burkholderia pseudomallei, which is endemic in northern Australia and Southeast Asia. We present the initial diagnostic dilemma of a febrile patient from northern Australia with type 1 diabetes mellitus and negative blood cultures. After a 6-week history of fevers and undifferentiated abdominal pain, MRI of her spine revealed a psoas abscess. She underwent drainage of the abscess which cultured B. pseudomallei. She completed 6 weeks of intravenous (IV) ceftazidime and oral trimethoprim/sulphamethoxazole (TMP/SMX) followed by a 12-week course of oral TMP/SMX. We postulate that the likely route of infection was inoculation via her skin, the integrity of which was compromised from her insulin pump insertion sites and an underlying dermatological condition.Learning points:Diabetes mellitus is the strongest risk factor for developing melioidosis.Atypical infections need to be considered in individuals with diabetes mellitus who are febrile, even if blood cultures are negative.There is heterogeneity in the clinical presentation of melioidosis due to variable organ involvement.Consider melioidosis in febrile patients who have travelled to northern Australia, Asia and other endemic areas.

Identification of Two novel reassortant avian influenza a (H5N6) viruses in whooper swans in Korea, 2016

BackgroundOn November 20, 2016 two novel strains of H5N6 highly pathogenic avian influenza virus (HPAIVs) were isolated from three whooper swans (Cygnus cygnus) at Gangjin Bay in South Jeolla province, South Korea. Identification of HPAIVs in wild birds is significant as there is a potential risk of transmission of these viruses to poultry and humans.ResultsPhylogenetic analysis revealed that Gangjin H5N6 viruses classified into Asian H5 clade 2.3.4.4 lineage and were distinguishable from H5N8 and H5N1 HPAIVs previously isolated in Korea. With the exception of the polymerase acidic (PA) gene, the viruses were most closely related to A/duck/Guangdong/01.01SZSGXJK005-Y/2016 (H5N6) (98.90 ~ 99.74%). The PA genes of the two novel Gangjin H5N6 viruses were most closely related to AIV isolates previously characterized from Korea, A/hooded crane/Korea/1176/2016 (H1N1) (99.16%) and A/environment/Korea/W133/2006 (H7N7) (98.65%). The lack of more recent viruses to A/environment/Korea/W133/2006 (H7N7) indicates the need for analysis of recent wild bird AIVs isolated in Korea because they might provide further clues as to the origin of these novel reassortant H5N6 viruses.ConclusionsAlthough research on the origins and epidemiology of these infections is ongoing, the most likely route of infection for the whooper swans was through direct or indirect contact with reassortant viruses shed by migratory wild birds in Korea. As H5N6 HPAIVs can potentially be transmitted to poultry and humans, continuous monitoring of AIVs among wild birds will help to mitigate this risk.

Fine morphology and phylogeny of Spiroplasma sp. isolated from eyes of scrapie sheep

Spiroplasma sp. isolated from eyes of sheep with terminal scrapie were reported previously to produce intracellular pathology typical for neurodegenerative diseases in experimentally infected cell lines (Bastian et al., 2014). These isolates have not been yet characterized morphologically or genetically. The paper presents light and electron microscopic description, as well as 16SrDNA sequence data-based phylogenetic analysis of these isolates grown cell-free. The microorganisms were elongated cells of transient helicity up to 10 μm long, and about 100 nm in diameter. Transmission and scanning electron microscopies revealed variable morphology, including presence of helical and non-helical forms. The 16SrDNA from the novel isolates revealed >99.9% similarity to the orthologues from S. chrysopicola and S. syrphidicola, common commensals of tabanid and syrphid flies. On phylogenetic trees the scrapie sheep isolates fell into the S. chrysopicola—S. syrphidicola—TAAS group of Diptera-associated species suggesting likely route of infection through flies contacting eyes of sheep in pastures. The question, whether microorganisms occasionally contaminate eyes of sheep with terminal scrapie upon contacts with flies, or spiroplasmas are linked with the disease, and tabanids play a role of their obligate or facultative vectors and reservoirs, warrants further investigation.

Genome Sequence of Vibrio parahaemolyticus VP152 Strain Isolated from Penaeus indicus in Malaysia.

Vibrio parahaemolyticus is a Gram-negative bacterium that naturally occurs in marine associated aquatic environments (Letchumanan et al., 2014; Malcolm et al., 2015). This bacterium causes highest number of seafood-associated gastroenteritis in many countries including United States and Asian countries (Scallan et al., 2011; Newton et al., 2012). V. parahaemolyticus is often been isolated from aquatic environments such as seawater and marine sediment, as well as from vertebrate and invertebrate seafood products (Shen et al., 2009). The most likely route of infection in humans is reported to be associated with consumption of raw or improperly cooked seafood (Daniels et al., 2000; Jun et al., 2014; Hazen et al., 2015; Raghunath, 2015; Law et al., 2015). Recently, V. parahaemolyticus has been demonstrated to be a major source of infection in the aquaculture industry (Letchumanan et al., 2014; Soto-Rodriguez et al., 2015; Tey et al., 2015). Aquaculture farmers rely on a wide range of antibiotics to prevent (prophylactic use) and treat (therapeutic use) bacterial infections in fish and invertebrates (Cabello et al., 2013). The extensive use of antibiotics and other chemotherapeutics in aquaculture has led to the emergence of multidrug resistant strains in the biosphere (Letchumanan et al., 2015a, 2016; Rao and Lalitha, 2015). Multidrug resistant V. parahaemolyticus strains have been isolated and detected from shrimp in Thailand (Yano et al., 2014), Malaysia (Al-Othrubi et al., 2011; Sani et al., 2013; Letchumanan et al., 2015b,c) and China (Peng et al., 2010; Xu et al., 2014). Resistance toward clinically used antibiotics will eventually hamper the treatment of bacterial infections in humans and potentially increase the fatality rate (Daniels et al., 2000). Therefore, monitoring Vibrio species in aquaculture surroundings is crucial for both human health and the aquaculture industry. In our previous study, we have isolated environmental V. parahaemolyticus strains from two types of Malaysian shrimp, Penaeus indicus and Solenocera subnuda. We detected the thermostable direct hemolysin (tdh) and thermostable direct related hemolysin (trh) virulence genes through a PCR based assay and studied the antibiotic resistance profile of all the isolated strains (Letchumanan et al., 2015c). V. parahaemolyticus VP152 was isolated from Penaeus indicus (Banana prawn) and originated from a supermarket sample. This strain did not possess both the tdh and trh virulence genes, which are responsible for causing diseases in humans and marine animals. Despite the fact that V. parahaemolyticus VP152 strain does not have tdh and trh virulence genes properties, the strain cannot be ignored in light of the fact that it exhibits multidrug resistance profiles toward 11/14 antibiotics tested. Based on the antibiotic susceptibility phenotype, the strain exhibited multiple-antibiotic resistance toward ampicillin, oxytetracycline, nalidixic acid, ampicillin/sulbactam, tetracycline, third generation cephalos porins (cefotaxime and ceftazidime), aminoglycosides (amikacin, kanamycin, and gentamicin) and trimethoprim/sulfameth oxazole (Letchumanan et al., 2015c). This is a worrying situation as the antibiotic resistant profiles shown by V. parahaemolyticus VP152 include the recommended antimicrobial agents used in treatment of Vibrio spp. infections, including third generation cephalosporin, fluoroquinolones, aminoglycosides, tetracycline, gentamicin, trimethoprim/sulfamethoxazole (Daniels and Shafaie, 2000; Shaw et al., 2014). Therefore, the whole genome sequence of V. parahaemolyticus VP152 was studied with respect to the multidrug resistance profiles to gain a better understanding of the antibiotic resistant patterns. The availability of this genome sequence of V. parahaemolyticus VP152 will aid as a basis for further in-depth analysis of the antibiotic resistance profile of environmental V. parahaemolyticus.

First Reported Detection of Influenza A (H1N1)pdm09 in Turkeys in the United Kingdom

We report the first occurrence of pandemic (H1N1) 2009 virus [A(H1N1)pdm09] infection on two epidemiologically linked turkey breeder premises in the United Kingdom during December 2010 and January 2011. Clinically, the birds showed only mild signs of disease, with the major presenting sign being an acute and marked reduction in egg production, leading to the prompt reporting of suspected avian notifiable disease for official investigation. Presence of A(H1N1)pdm09 infection in the United Kingdom turkey breeder flocks was confirmed by detailed laboratory investigations including virus isolation in embryonated specific pathogen-free fowls' eggs, two validated real-time reverse transcription-PCR tests, and nucleotide sequencing of the hemagglutinin and neuraminidase genes. These investigations revealed high nucleotide identity with currently circulating human A(H1N1)pdm09 strains, suggesting that human-to-poultry transmission (reverse zoonosis) was the most likely route of infection. Peak levels of human influenza-like illness community transmission also coincided with the onset of clinical signs in both affected turkey breeder flocks. This case demonstrated the value of the existing passive surveillance framework and associated veterinary and laboratory infrastructure that enables the detection and management of both exotic and new and emerging disease hazards and risks. The case also presents further evidence of the susceptibility of turkeys to infection with influenza A viruses of nonavian origin.

Variant CJD infection in the spleen of a neurologically asymptomatic UK adult patient with haemophilia

All UK patients with bleeding disorders treated with any UK-sourced pooled factor concentrates between 1980 and 2001 have been informed that they may be at an increased risk of infection with variant Creutzfeldt-Jakob disease (vCJD). We describe a study to detect disease-associated, protease-resistant prion protein (PrP(res)) in 17 neurologically aymptomatic patients with haemophilia considered to be at increased risk of vCJD. Materials from 11 autopsy and seven biopsy cases were analysed for PrP(res). The tissues available from each case were variable, ranging from a single biopsy sample to a wide range of autopsy tissues. A single specimen from the spleen of one autopsy case gave a strong positive result on repeated testing for PrP(res) by Western blot analysis. This tissue came from a 73-year-old male patient with no history of neurological disease, who was heterozygous (methionine/valine) at codon 129 in the prion protein gene. He had received over 9000 units of factor VIII concentrate prepared from plasma pools known to include donations from a vCJD-infected donor, and some 400,000 units not known to include donations from vCJD-infected donors. He had also received 14 units of red blood cells and had undergone several surgical and invasive endoscopic procedures. Estimates of the relative risks of exposure through diet, surgery, endoscopy, blood transfusion and receipt of UK-sourced plasma products suggest that by far the most likely route of infection in this patient was receipt of UK plasma products.

A case of acute hepatitisC caused by interspousal transmission after 30years of marriage.

We describe a case of interspousal transmission of hepatitisC virus (HCV) infection after 30years of marriage which was confirmed by gene analysis. A 60-year-old man was referred to our hospital because of severe hepatic dysfunction. Laboratory findings showed that HCV-Ab titer and qualitative Amplicor HCV were both positive in low levels. Because the patient regularly consumes various health foods, it was initially difficult to rule out drug-induced hepatopathy, but the patient was diagnosed with acute hepatitisC when HCV antibody titer increased 4months later. Because his wife also tested positive for HCV antibody, interspousal transmission was suspected, and gene analysis was performed. Both husband and wife had HCV 1b, and the base sequence homology of 1087 base pairs (bp) in the NS5B region was 98.6% (99.4% at the amino acid level). In addition, upon analysis of the E1 and E2 junctional region sequence (268bp) including hypervariable region 1 (HVR-1), a close relationship (89.2-99.6%) between clones obtained from each spouse was observed, thus confirming that the source of infection was his wife. Thorough medical history taking suggested that sexual intercourse was the most likely route of infection. In previous large-scale clinical studies, the frequency of HCV infection between married couples has been extremely low, but it is important to obtain informed consent regarding the potential risk of infection.

FROG VIRUS 3-LIKE INFECTIONS IN AQUATIC AMPHIBIAN COMMUNITIES

Frog virus 3 (FV3) and FV3-like viruses, are members of the genus Ranavirus (family Iridoviridae), and they have been associated with infectious diseases that may be contributing to amphibian population declines. We examined the mode of transmission of an FV3-like virus, and potential hosts and reservoirs of the virus in a local amphibian community. Using the polymerase chain reaction to detect infected animals, we found an FV3-like virus in south-central Ontario, Canada, amphibian communities, where it infects sympatric amphibian species, including ranid and hylid tadpoles (Rana sylvatica, Hyla versicolor, and Pseudacris spp.), larval salamanders (Ambystoma spp.), and adult eastern-spotted newts (Notophthalmus viridescens). The high prevalence of FV3-like infections in caudate larvae suggests that salamanders are likely to be both hosts and reservoirs. In laboratory FV3 challenges of R. sylvatica, the rate of infection was dependent on the amount of virus to which the animals were exposed. In addition, although vertical transmission was suspected, horizontal transmission through exposure to infected pond water is the most likely route of infection in tadpoles. Based on our observations, a simple model of FV3/FV3-like virus transmission postulates that, in aquatic amphibian communities, transmission of the virus occurs between anuran and urodele species, with ambystomatid salamanders the most likely reservoir for the ranavirus in our study.

Bone and Joint Infections Caused by Haemophilus parainfluenzae

Abstract Haemophilus parainfluenzae has been implicated in septic arthritis and osteomyelitis, but its role remains uncertain in view of its assumed low pathogenicity and of its being a fastidious organism. Reported in this study are 2 cases of bone and joint infections caused by H. parainfluenzae (vertebral osteomyelitis with epidural and psoas abscesses, and sacroiliitis with osteomyelitis), followed by a review of the corresponding English-language literature. Ten previously reported cases were discussed together with our 2 cases. Up to 75% of patients were found to have a predisposing factor before infection. The hematogenous spread was the most likely route of infection. Eleven of these 12 patients were cured, and one was improved clinically by antibiotic therapy alone or in conjunction with surgery.

Case-control study for risk factors for Q Fever in southwest England and Northern Ireland.

Q fever (Coxiella burnetti) is thought to account for 1% (700 cases) of community acquired pneumonia in the United Kingdom each year, and can result in serious complications such as endocarditis. Although outbreaks have frequently been reported worldwide, the causes are often not clearly identified and there have been few studies of risk factors in sporadic cases. We conducted a matched case-control study. Cases of acute Q fever in people aged over 15 years in southwest England and Northern Ireland were identified from January 2002 to December 2004. Controls were matched for age, sex and the general practice at which they were registered. Questionnaires asking about contact with animals, and leisure and work activities, were posted to cases and controls. Questionnaires were completed by 39/50 (78%) of the cases and 90/180 (50%) of the controls. In the single variable analysis, occupational exposure to animals or animal products was the only risk factor associated with cases at the 5% level (P=0.05, odds ratio (OR) 3.4). Long term illness appeared to be significantly protective (P=0.03, OR 0.3). In multivariable analysis the strength of association between occupational exposure and illness remained high (OR 3.6, 95% confidence interval (CI) 0.9 to 14.8) and smoking emerged as a possible risk factor. This is the first case-control study to identify occupational exposure to animals or animal products as the most likely route of infection in sporadic cases as opposed to outbreaks.

Stigma and HIV infection in Russia

Few studies have examined the personal and social consequences of stigma associated with HIV infection in Russia, a country with one of the most rapidly advancing HIV epidemics globally. By May 2005, Samara Oblast, Russia had 24,022 notified seropositive individuals. Focus-group discussions with randomly sampled seropositive and seronegative individuals, matched by age, gender and education were selected from the general population and used to provide an informal forum for discussion of attitudes to HIV and potentially stigmatizing behavior. The results demonstrated that the perception that HIV was associated with immoral behaviour underpinned stigma. Discriminating attitudes are strongly associated with misperceptions regarding transmission and frequent over-estimation of risks from casual contact. The general population was unforgiving to those who had become infected sexually or through drug use. Infection through a medical procedure or from an assault was perceived as a likely route of infection. Knowledge of population attitudes and perceptions, as well as those who are HIV-positive, is critical for successful interventions and to encourage people to come forward for HIV testing. This research offers insights into the distance that needs to be traveled if stigma is to be addressed in wider efforts to control HIV in Russia.

New developments in the detection and identification of processed animal proteins in feeds

It is generally accepted that the most likely route of infection of cattle with bovine spongiform encephalopathy (BSE) is by consumption of feeds containing low levels of processed animal proteins (PAPs). This likely route of infection resulted in feed bans, which were primarily aimed at ruminant feeds, and were later extended to all feeds for farmed animals. The feed bans were expected to develop into a future enforcement of the “species-to-species” ban, which prohibits only the feeding of animal-specific proteins to the same species. The species-to-species ban requires support of species-specific identification methods. In the European Union, microscopic evaluation is currently the only accepted method for the detection and characterization of PAPs in feeds, since it is possible to detect contaminations at the requested level of 1 g/kg with hardly any false negative nor positive results. This method is predominantly focused on the presence and characteristics of bone fragments, although other structures, e.g. muscle fibres, may provide circumstantial evidence of the respective animal types. Recent developments are the identification of bone fragments at the level of classes (mammal versus bird versus fish), supported by image analysis of bone characteristics. Detection of DNA and specific proteins are additional methods that can be applied for the identification of PAPs in feeds. DNA is known to be very specific for animal species and breeds, whereas proteins can also indicate the type of tissue. The latter aspect is important to differentiate between proteins that are authorised in animal nutrition from banned proteins. Improvements can be noted in recent years for both methods. For a proper application of polymerase chain reaction (PCR) to detect specific sequences of DNA, primer sets have been developed which amplify a DNA sequence shorter than approximately 100 nucleotides. Specific antibodies have been developed for protein detection of ruminant or bovine material. Recent results of various studies indicate that specific DNA and protein detection methods can detect PAPs at a contamination level of 1 g/kg. However, full validation of these methods still needs to be carried out. Other methods such as near-infrared spectroscopy (NIRS), near-infrared microscopy (NIRM), near-infrared imaging, liquid chromatography (LC) and olfactometry techniques can and will be applied for the detection of PAPs. NIRS is a non-destructive method that can be applied on-line in feed production plants. Generally, the detection limit is still too high to be applied in official control laboratories. Nevertheless, industrial application is feasible. NIRM and near-infrared imaging are techniques that allow collection of near-infrared spectra from individual particles. The level of detection is lower than 1 g/kg since it is based on the microscopic technique, in combination with the option of identification of the individual particles. LC is based on the detection and, if present, the ratio of different polypeptides. For example, carnosine is mainly present in mammals and anserine mainly found in birds. Olfactometry is based on detection of volatile non-specific agents. It is a non-destructive and fast technique. For both LC and olfactometry it appears that the presence of fish material masks the detection of proteins of land animals, even at a contamination level of 5 g/kg. Since 2003 five different proficiency studies and ring trials have been organized. The first proficiency study, allowing the participants to apply their own protocol, revealed that correct microscopic detection of 1 g/kg of mammalian PAP in the presence of 50 g fish meal/kg was realised in 0.44 of the cases. However, a bench mark study organized in the same year showed that a microscopic detection of 0.98 can be reached provided the application of an optimal protocol and a sufficient level of expertise. More recent studies showed that training, the application of a decision support system and use of an improved microscopy protocol resulted in a higher sensitivity. An attractive approach is the combination of the very low detection level of microscopy with identification by other methods. Several strategies for a combination of screening and confirmation methods are discussed in the present paper. The new developments in methodology will support current or new legislation ( e.g. species-to-species ban, general application of fish meal).

Use of genomic analysis of varicella-zoster virus to investigate suspected varicella-zoster transmission within a renal unit

Background The source of hospital-acquired chickenpox infection may be presumed from a known exposure, but has not been previously proven using genomic analysis. Objective Investigation of suspected VZV transmission was done using single nucleotide polymorphism genomic analysis. Study design Comparison was made of viral isolates from two patients with chickenpox on the same ward who were not known to have had direct contact. Results An identical genotype in the variable R1 region of the VZV was isolated from the two patients. Conclusion Inapparent hospital-acquired transmission was the most likely route of infection.

Infected adenolymphoma: a new parotid syndrome.

Abstract Two cases are presented of acute inflammatory swellings developing in a parotid gland in elderly men and going on to abscess formation. Both proved to be due to secondary infection of adenolymphomas. In the first case the rupture of the abscess led to a salivary fistula; in the second an associated septicaemia threatened the life of the patient. Both patients were successfully treated by a conservative parotidectomy. From a consideration of the clinical and pathological features, it is suggested that the most likely route of infection of the tumours is the blood-stream.

Primary Tuberculous Osteomyelitis of the Mandible

Primary tuberculous osteomyelitis of the mandible is uncommon. Only 121 cases have been reported in the English language literature. This report is of a 19-year-old woman with primary tuberculosis of the mandible. The clinical presentation mimicks a dento-alveolar abscess and this report emphasises the importance of considering tuberculous osteomyelitis in the differential diagnosis of jaw swellings. The likely route of infection, difficulties in diagnosis, and management of the patient are discussed.