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PURPOSE Helicobacter pylori could theoretically induce ocular adnexal lymphoma (OAL) via 2 mechanisms: the first is that of infection within the ocular adnexa and the second is that of infection within the gastric mucosa, leading to the malignant transformation of lymphocytes that migrate to the ocular adnexa, forming a primary "ectopic" cancer. This study investigated if an association exists between gastric H. pylori or ocular adnexal H. pylori and OAL. METHODS Prospective case-control study including cases with OAL and controls with nonlymphomatous pathologies. Gastric H. pylori infection was assessed via serologic antibody testing. Ocular adnexal infection was assessed via polymerase chain reaction testing for H. pylori and Chlamydia psittaci within ocular adnexal samples. RESULTS Seventy-two patients were enrolled, of whom 18 had lymphoma and 54 nonlymphomatous pathologies. H. pylori antibodies were present in 5 cases (28%) and 18 controls (33%) (95% CI, 0.24%-2.50%, p = 0.78). All ocular adnexal specimens were negative for H. pylori and C. psittaci infection. The only relevant statistically significant difference between cases and controls was a history of gastric ulcer (95% CI, 1.23%-44.80%, p = 0.03). CONCLUSIONS In the study's population, infection of gastric mucosa with H. pylori does not appear to influence the development of OAL. Also, H. pylori or C. psittaci infection within the ocular adnexa does not appear to influence the development of OAL. In the study's practice, authors do not recommend antibiotic administration or routine gastroscopy for patients with OAL. The authors do recommend referral of OAL patients with gastric symptoms to a gastroenterologist.

Once considered as inert, the extracellular matrix recently revealed to be biologically active. Elastin is one of the most important components of the extracellular matrix. Many vital organs including arteries, lungs and skin contain high amounts of elastin to assure their correct function. Physiologically, the organism contains a determined quantity of elastin from the early development which may remain physiologically constant due to its very long half-life and very low turnover. Taking into consideration the continuously ongoing challenges during life, there is a physiological degradation of elastin into elastin-derived peptides which is accentuated in several disease states such as obstructive pulmonary diseases, atherosclerosis and aortic aneurysm. These elastin-derived peptides have been shown to have various biological effects mediated through their interaction with their cognate receptor called elastin receptor complex eliciting several signal transduction pathways. In this review, we will describe the production and the biological effects of elastin-derived peptides in physiology and pathology.

Alzheimer’s disease (AD) is the most prevalent dementia in the world. Its cause(s) are presently largely unknown. The most common explanation for AD, now, is the amyloid cascade hypothesis, which states that the cause of AD is senile plaque forma- tion by the amyloid β peptide, and the formation of neurofibrillary tangles by hyperphosphorylated tau. A second, burgeoning theory by which to explain AD is based on the infection hypothesis. Much experimental and epidemiological data support the involvement of infections in the development of dementia. According to this mechanism, the infection either directly or via microbial virulence factors precedes the formation of amyloid β plaques. The amyloid β peptide, possessing antimicrobial properties, may be beneficial at an early stage of AD, but becomes detrimental with the progression of the disease, concomi- tantly with alterations to the innate immune system at both the peripheral and central levels. Infection results in neuroinflam- mation, leading to, and sustained by, systemic inflammation, causing eventual neurodegeneration, and the senescence of the immune cells. The sources of AD-involved microbes are various body microbiome communities from the gut, mouth, nose, and skin. The infection hypothesis of AD opens a vista to new therapeutic approaches, either by treating the infection itself or modulating the immune system, its senescence, or the body’s metabolism, either separately, in parallel, or in a multi-step way., Basque Government under the grant “Artificial Intelligence in BCAM number EXP. 2019/00432”

Alzheimer's disease is one of the most devastating neurodegenerative diseases. The exact cause of the disease is still not known although many scientists believe in the beta amyloid hypothesis which states that the accumulation of the amyloid peptide beta (Aβ) in brain is the initial cause which consequently leads to pathological neuroinflammation. However, it was recently shown that Aβ may have an important role in defending the brain against infections. Thus, the balance between positive and negative impact of Aβ may determine disease progression. Microglia in the brain are innate immune cells, and brain-initiated inflammatory responses reflected in the periphery suggests that Alzheimer's disease is to some extent also a systemic inflammatory disease. Greater permeability of the blood brain barrier facilitates the transport of peripheral immune cells to the brain and vice versa so that a vicious circle originating on the periphery may contribute to the development of overt clinical AD. Persistent inflammatory challenges by pathogens in the periphery, increasing with age, may also contribute to the central propagation of the pathological changes seen clinically. Therefore, the activation status of peripheral innate immune cells may represent an early biomarker of the upcoming impact on the brain. The modulation of these cells may thus become a useful mechanism for modifying disease progression.

The mechanisms of neurodegeneration in Alzheimer's disease (AD) remain under investigation. Alterations in the blood-brain barrier facilitate exchange of inflammatory mediators and immune cells between the brain and the periphery in AD. Here, we report analysis of phenotype and functions of polymorphonuclear neutrophils (PMN) in peripheral blood from patients with amnestic mild cognitive impairment (aMCI, n = 13), patients with mild AD (mAD, n = 15), and healthy elderly controls (n = 13). Results showed an increased expression of CD177 in mAD but not in healthy or aMCI patients. IL-8 stimulated increased expression of the CD11b integrin in PMN of healthy subjects in vitro but PMN of aMCI and mAD patients failed to respond. CD14 and CD16 expression was lower in PMN of mAD but not in aMCI individuals relative to controls. Only PMN of aMCI subjects expressed lower levels of CD88. Phagocytosis toward opsonized E. coli was differentially impaired in PMN of aMCI and mAD subjects whereas the capacity to ingest Dextran particles was absent only in mAD subjects. Killing activity was severely impaired in aMCI and mAD subjects whereas free radical production was only impaired in mAD patients. Inflammatory cytokine (TNFα, IL-6, IL-1β, IL-12p70) and chemokine (MIP-1α, MIP-1β, IL-8) production in response to LPS stimulation was very low in aMCI and nearly absent in mAD subjects. TLR2 expression was low only in aMCI. Our data showed a differentially altered capacity of PMN of aMCI and mAD subjects to respond to pathological aggression that may impact impaired responses associated with AD development.

Accumulating evidence suggests that the propagation of hyperphosphorylation of tau protein and the amyloid-β peptide can be mediated by extracellular vesicles (EVs) and be associated with the onset and the progression of Alzheimer's disease (AD). As EVs may transfer between the brain and the blood, we have thus hypothesized that the total plasma EVs (pEVs) may contain potential markers to predict the mild cognitive impairment (MCI) and AD progression. We have thus quantified AD-related proteins in isolated pEVs from controls, MCI and AD subjects. In pEVs, we observed early changes of total tau (tTau), amyloid precursor protein levels, and phospho-tau (pTau)-T181/tTau ratio from MCI subjects and late increases of Aβ42 and pTau-T181 levels from patients with moderate AD. Interestingly, abnormal amyloid precursor protein levels and pTau-T181/tTau ratio in pEVs demonstrated a high accuracy to define MCI and AD staging. Although larger samples sizes will be needed to generate well-powered investigations, these preliminary results highlighted the potential of AD-related proteins enriched in pEVs as a sensitive tool for differentiating patients with MCI to patients with AD and monitoring AD progression.

BACKGROUND AND RATIONALE FOR THE STUDY:The global plan to eradicate hepatitis C (HCV) led by the World Health Organisation (WHO) outlines the use of highly effective direct-acting antiviral drugs (DAAs) to achieve elimination by 2030. Identifying individuals with active disease and investigation of the breadth of diversity of the virus sub-Saharan Africa (SSA) is essential as genotypes in this region (where very few clinical trials have been carried out) are distinct from those found in other parts of the world. We undertook a population-based nested case-control study in Uganda and obtained additional samples from the Democratic Republic of Congo (DRC), to estimate the prevalence of HCV, assess strategies for disease detection using serological and molecular techniques, and characterise genetic diversity of the virus. Using next generation (NGS) and Sanger sequencing, we aimed to identify strains circulating in East and Central Africa. MAIN RESULTS:7751 Ugandan patients were initially screened for HCV and 20 PCR positive samples obtained for sequencing. Serological assays were found to vary significantly in specificity for HCV. HCV strains detected in Uganda included genotypes (g) 4k, 4p, 4q and 4s and a new unassigned genotype 7 HCV strain. Two additional unassigned g7 strains were identified in patients originating from DRC (one partial and one full ORF sequence). These g4 and 7 strains contain NS3 and NS5A polymorphisms associated with resistance to DAAs in other genotypes. Clinical studies are therefore indicated to investigate treatment response in infected patients. CONCLUSION:While HCV prevalence and genotypes have been well characterised in patients in well-resourced countries, clinical trials are urgently required in SSA where highly diverse g4 and 7 strains circulate. This article is protected by copyright. All rights reserved.

HIV infection in the combination antiretroviral therapy (cART) era has become a chronic disease with a life expectancy almost identical to those free from this infection. Concomitantly, chronic diseases such as neurodegenerative diseases have emerged as serious clinical problems. HIV-induced cognitive changes, although clinically very diverse are collectively called HIV-associated neurocognitive disorder (HAND). HAND, which until the introduction of cART manifested clinically as a subcortical disorder, is now considered primarily cognitive disorder, which makes it similar to diseases like Alzheimer's (AD) and Parkinson's disease (PD). The pathogenesis involves either the direct effects of the virus or the effect of viral proteins such as Tat, Ggp120, and Nef. These proteins are either capable of destroying neurons directly by inducing neurotoxic mediators or by initiating neuroinflammation by microglia and astrocytes. Recently, it has become recognized that HIV infection is associated with increased production of the beta-amyloid peptide (Aβ) which is a characteristic of AD. Moreover, amyloid plaques have also been demonstrated in the brains of patients suffering from HAND. Thus, the question arises whether this production of Aβ indicates that HAND may lead to AD or it is a form of AD or this increase in Aβ production is only a bystander effect. It has also been discovered that APP in HIV and its metabolic product Aβ in AD manifest antiviral innate immune peptide characteristics. This review attempts to bring together studies linking amyloid precursor protein (APP) and Aβ production in HIV infection and their possible impact on the course of HAND and AD. These data indicate that human defense mechanisms in HAND and AD are trying to contain microorganisms by antimicrobial peptides, however by employing different means. Future studies will, no doubt, uncover the relationship between HAND and AD and, hopefully, reveal novel treatment possibilities.

Background Whole genome sequencing (WGS) studies can enhance our understanding of the role of patients with asymptomatic Clostridium difficile colonization in transmission. Methods Isolates obtained from patients with Clostridium difficile infection (CDI) and colonization identified in a study conducted during 2006 - 2007 at six Canadian hospitals underwent typing by pulsed-field gel electrophoresis, multilocus sequence typing, and WGS. Isolates from incident CDI cases not in the initial study were also sequenced where possible. Ward movement and typing data were combined to identify plausible donors for each CDI case, as defined by shared time and space within predefined limits. Proportions of plausible donors for CDI cases that were colonized, infected, or both were examined. Results Five hundred and fifty-four isolates were sequenced successfully, 353 from colonized and 201 from CDI cases. The NAP1/027/ST1 strain was the most common strain, found in 124 (62%) of infected and 92 (26%) of colonized patients. A donor with a plausible ward link was found for 81 CDI cases (40%) using WGS with a threshold of ≤2 single nucleotide variants to determine relatedness. Sixty-five (32%) CDI cases could be linked to both infected and colonized donors. Exclusive linkages to infected and colonized donors were found for 28 (14%) and 12 (6%) CDI cases, respectively. Conclusion Colonized patients contribute to transmission, but CDI cases are more likely linked to other infected patients than colonized patients in this cohort with high rates of NAP1/027/ST1 strain, highlighting the importance of local prevalence of virulent strains in determining transmission dynamics.

Senile amyloid plaques are one of the main hallmarks of Alzheimer's disease (AD). They correspond to insoluble deposits of amyloid-β peptides (Aβ) and are responsible for the inflammatory response and neurodegeneration that lead to loss of memory. Recent data suggest that Aβ possess antimicrobial and anti-viral activity in vitro. Here, we have used cocultures of neuroglioma (H4) and glioblastoma (U118-MG) cells as a minimal in vitro model to investigate whether Aβ is produced by neuroglioma cells and whether this could result in protective anti-viral activity against HSV-1 infection. Results showed that H4 cells secreted Aβ42 in response to HSV-1 challenge and that U118-MG cells could rapidly internalize Aβ42. Production of pro-inflammatory cytokines TNFα and IL-1β by H4 and U118-MG cells occurred under basal conditions but infection of the cells with HSV-1 did not significantly upregulate production. Both cell lines produced low levels of IFNα. However, extraneous Aβ42 induced strong production of these cytokines. A combination of Aβ42 and HSV-1 induced production of pro-inflammatory cytokines TNFα and IL-1β, and IFNα in the cell lines. The reported anti-viral protection of Aβ42 was revealed in transfer experiments involving conditioned medium (CM) of HSV-1-infected H4 cells. CM conferred Aβ-dependent protection against HSV-1 replication in de novo cultures of H4 cells challenged with HSV-1. Type 1 interferons did not play a role in these assays. Our data established that H4 neuroglioma cells produced Aβ42 in response to HSV-1 infection thus inhibiting secondary replication. This mechanism may play a role in the etiology of AD.

Aging is accompanied by many physiological changes including those in the immune system. These changes are designated as immunosenescence indicating that age induces a decrease in immune functions. However, since many years we know that some aspects are not decreasing but instead are increasing like the pro-inflammatory activity by the innate immune cells, especially by monocytes/macrophages. Recently it became evident that these cells may possess a sort of memory called trained memory sustained by epigenetic changes occurring long after even in the absence of the initiator aggressor. In this review we are reviewing evidences that such changes may occur in aging and describe the relationship between inflamm-aging and immunosenescence as an adaptation/remodelling process leading on one hand to increased inflammation and on the other to decreased immune response (immune-paralysis) mastered by the innate immune system. These changes may collectively induce a state of alertness which assure an immune response even if ultimately resulting in age-related deleterious inflammatory diseases.

Alzheimerś disease (AD) is a progressive irreversible neurological brain disorder characterized by accumulation of amyloid-β, amyloid plaques, and neurofibrillary tangles. Inflammation and immune alterations have been linked to AD, suggesting that the peripheral immune system plays a role during the asymptomatic period of AD. NK cells participate in innate immune surveillance against intracellular pathogens and malignancy but their role in AD remains controversial. We have investigated changes in peripheral NK cell phenotypes and functions in amnestic mild cognitive impairment (aMCI, n = 10), patients with mild AD (mAD, n = 11), and healthy elderly controls (n = 10). Patients selected according to NINCDS-ADRDA criteria were classified using neuropsychological assessment tests. Phenotype analysis revealed differences in expression of CD16 (increased in mAD), NKG2A (decreased in aMCI), and TLR2 and TLR9 (both decreased in mAD). Functional assays revealed that NK cell killing activity and degranulation (CD107 expression) were unchanged in the three groups. In contrast, expression of the CD95 receptor was increased in aMCI and mAD. Granzyme B expression and cytokine production (TNFα, IFNγ) were increased in aMCI but not in mAD. CCL19- but not CCL21-dependent chemotaxis was decreased in aMCI and mAD, despite the fact that CCR7 expression was increased in aMCI. Our data suggest that the number of alterations observed in peripheral NK cells in aMCI represent an activation state compared to mAD patients and that may reflect an active immune response against a still to be defined aggression.

Background Clostridium difficile (CD) is the leading cause of health care–associated diarrhea and can result in asymptomatic carriage. Rates of asymptomatic CD colonization on hospital admission range from 1.4%-21%. The objective of this study was to evaluate host and bacterial factors associated with colonization on admission. Methods The Consortium de recherche quebecois sur le Clostridium difficile study provided data for analysis, including demographic information, known risk factors, and potential confounding factors, prospectively collected for 5,232 patients from 6 hospitals in Quebec and Ontario over 15 months from 2006-2007. Stool or rectal swabs were obtained for culture on admission. Pulsed-field gel electrophoresis was performed on the isolates. The presence of antibody against CD toxins A and B was measured. Results There were 212 (4.05%) patients colonized with CD on admission, and 5,020 patients were not colonized with CD. Multivariate logistic regression analysis showed that hospitalization within the last 12 months, use of corticosteroids, prior CD infection, and presence of antibody against toxin B were associated with colonization on admission. Of patients colonized on admission, 79.4% had non-NAP1, non-NAP2 strains. Conclusion There are identifiable risk factors among asymptomatic CD carriers that could serve in their detection and provide a basis for targeted screening.

Development of quick and reliable methods to investigate antibiotic susceptibility of bacteria is vital to prevent inappropriate and untargeted use of antibiotics and control the antibiotic resistance crisis. The authors have developed an innovative, low-cost and rapid approach to evaluate antibiotic susceptibility of bacteria by employing photoluminescence (PL) emission of photocorroding GaAs/AlGaAs quantum well (QW) biochips. The biochips were functionalized with self-assembled monolayers of biotinylated polyethylene glycol thiols, neutravidin and biotinylated antibodies to immobilize bacteria. The illumination of a QW biochip with the above bandgap radiation leads to formation of surface oxides and dissolution of a limited thickness GaAs cap material (≤10nm) that results in the appearance of a characteristic maximum in the PL plot collected over time. The position of the PL maximum depends on the photocorrosion rate which, in turn, depends on the electric charge immobilized on the surface of the GaAs/AlGaAs biochips. Bacteria captured on the surface of biochips retard the PL maximum, while growth of these bacteria further delays the PL maximum. For the bacteria affected by antibiotics a faster occurring PL maximum, compared with growing bacteria, is observed. By exposing bacteria to nutrient broth and penicillin or ciprofloxacin, the authors were able to distinguish in situ antibiotic-sensitive and resistant Escherichia coli bacteria within less than 3h, considerable more rapid than with culture-based methods. The PL emission of the heterostructures was monitored with an inexpensive reader. This rapid determination of bacterial sensitivity to different antibiotics could have clinical and research applications.

Background Efficient viral load testing is needed for hepatitis C (HCV) surveillance and diagnosis. HCV viral load testing using dried blood spots (DBSs), made with a single drop of finger-prick whole blood on filter paper, is a promising alternative to traditional serum- or plasma-based approaches. Methods We adapted the Abbott Molecular m2000 instrument for high-throughput HCV viremia testing using DBSs with simple specimen processing and applied these methods to estimate the national burden of infection in the Democratic Republic of the Congo (DRC). We tested DBSs collected during the 2013-2014 DRC Demographic and Health Survey, including 1309 adults ≥40 years of age. HCV-positive samples underwent targeted sequencing, genotyping, and phylogenetic analyses. Results This high-throughput screening approach reliably identified HCV RNA extracted from DBSs prepared using whole blood, with a 95% limit of detection of 1196 (95% confidence interval [CI], 866-2280) IU/mL for individual 6-mm punches and 494 (95% CI, 372-1228) IU/mL for larger 12-mm punches. Fifteen infections were identified among samples from the DRC Demographic and Health Survey; the weighted country-wide prevalence of HCV viremia was 0.9% (95% CI, 0.3%-1.6%) among adults ≥40 years of age and 0.7% (95% CI, .6%-.8%) among human immunodeficiency virus-infected subjects. All successfully genotyped cases were due to genotype 4 infection. Conclusions DBS-based HCV testing represents a useful tool for the diagnosis and surveillance of HCV viremia and can easily be incorporated into specimen referral systems. Among adults ≥40 years of age in the DRC, 100000-200000 may have active infection and be eligible for treatment.

Amyloid plaques, the hallmark of Alzheimer's disease (AD), contain fibrillar β-amyloid (Aβ) 1-40 and 1-42 peptides. Herpes simplex virus 1 (HSV-1) has been implicated as a risk factor for AD and found to co-localize within amyloid plaques. Aβ 1-40 and Aβ 1-42 display anti-bacterial, anti-yeast and anti-viral activities. Here, fibroblast, epithelial and neuronal cell lines were exposed to Aβ 1-40 or Aβ 1-42 and challenged with HSV-1. Quantitative analysis revealed that Aβ 1-40 and Aβ 1-42 inhibited HSV-1 replication when added 2 h prior to or concomitantly with virus challenge, but not when added 2 or 6 h after virus addition. In contrast, Aβ 1-40 and Aβ 1-42 did not prevent replication of the non-enveloped human adenovirus. In comparison, antimicrobial peptide LL-37 prevented HSV-1 infection independently of its sequence of addition. Our findings showed also that Aβ 1-40 and Aβ 1-42 acted directly on HSV-1 in a cell-free system and prevented viral entry into cells. The sequence homology between Aβ and a proximal transmembrane region of HSV-1 glycoprotein B suggested that Aβ interference with HSV-1 replication could involve its insertion into the HSV-1 envelope. Our data suggest that Aβ peptides represent a novel class of antimicrobial peptides that protect against neurotropic enveloped virus infections such as HSV-1. Overproduction of Aβ peptide to protect against latent herpes viruses and eventually against other infections, may contribute to amyloid plaque formation, and partially explain why brain infections play a pathogenic role in the progression of the sporadic form of AD.

Amyloid-β (Aβ) peptides generated by the amyloidogenic pathway of amyloid-β protein precursor processing contribute significantly to neurodegeneration characteristic of Alzheimer's disease (AD). The involvement of Aβ peptides in the etiology of AD remains a subject of debate. Data published in the last 6 years by three different groups have added a new twist by revealing that Aβ peptides could act as antimicrobial peptides (AMP) in in vitro assays against some common and clinically relevant microorganisms, inhibit replication of seasonal and pandemic strains of influenza A and HSV-1 virus. These observations are of significance with respect to the notion that pathogens may be important contributors to the development of AD, particularly in the case of herpes simplex virus (HSV) infection, which often resides in the same cerebral sites where AD arises. Here, we review the data that support the interpretation that Aβ peptides behave as AMP, with an emphasis on studies concerning HSV-1 and a putative molecular mechanism that suggests that interactions between Aβ peptides and the HSV-1 fusogenic protein gB lead to impairment of HSV-1 infectivity by preventing the virus from fusing with the plasma membrane. A number of avenues for future research are suggested.

Clostridium difficile infection is the leading cause of health care-associated diarrhea, and the bacterium can also be carried asymptomatically. The objective of this study was to identify host and bacterial factors associated with health care-associated acquisition of C. difficile infection and colonization.We conducted a 15-month prospective study in six Canadian hospitals in Quebec and Ontario. Demographic information, known risk factors, potential confounding factors, and weekly stool samples or rectal swabs were collected. Pulsed-field gel electrophoresis (PFGE) was performed on C. difficile isolates to determine the genotype. Levels of serum antibodies against C. difficile toxins A and B were measured.A total of 4143 patients were included in the study; 117 (2.8%) and 123 (3.0%) had health care-associated C. difficile infection and colonization, respectively. Older age and use of antibiotics and proton-pump inhibitors were significantly associated with health care-associated C. difficile infection. Hospitalization in the previous 2 months; use of chemotherapy, proton-pump inhibitors, and H(2) blockers; and antibodies against toxin B were associated with health care-associated C. difficile colonization. Among patients with health care-associated C. difficile infection and those with colonization, 62.7% and 36.1%, respectively, had the North American PFGE type 1 (NAP1) strain.In this study, health care-associated C. difficile infection and colonization were differentially associated with defined host and pathogen variables. The NAP1 strain was predominant among patients with C. difficile infection, whereas asymptomatic patients were more likely to be colonized with other strains. (Funded by the Consortium de Recherche sur le Clostridium difficile.).

Heterosexual transmission of hepatitis C virus (HCV) is uncommon, with few studies undertaken in Central Africa. To determine the frequency of inter-spouse HCV transmission, cross-sectional studies of elderly individuals in Ebolowa, Cameroon and Nola, Central African Republic, in which, respectively, 24 and 83 long-term couples had been identified, were examined further. Blood samples were tested for antibody to HCV. Anti-HCV positive samples were genotyped by phylogenetic analysis of a fragment of the NS5B gene. In Nola, 4 out of 9 (44.4%) wives of anti-HCV positive husbands and 1 out of 74 (1.4%) wives of anti-HCV negative husbands were anti-HCV positive (P

The performances of commercial enzyme-linked immunosorbent assays (ELISAs) in detecting herpes simplex virus type 2 (HSV-2) antibodies have been inconsistent for African and human immunodeficiency virus (HIV)-positive populations. We compared the performances of the HerpeSelect and Kalon glycoprotein G2 ELISAs for patients with genital ulcer disease in Ghana and the Central African Republic. Sera from 434 women were tested with the HerpeSelect assay, and a subsample ( n = 199) was tested by the Kalon assay. Ulcer swabs and cervicovaginal lavage samples were tested for HSV-2 DNA by PCR. HSV-2-seronegative women with detectable genital HSV-2 DNA were retested for HSV-2 antibodies 14 and 28 days later by the two ELISAs. A total of 346 (80%) women were positive by HerpeSelect at baseline, and 225 (54%) had detectable genital (lesional or cervicovaginal) HSV-2 DNA. Sixty-six (19%) HerpeSelect-positive samples had low-positive index values (1.1 to 3.5), and 58% of these samples had detectable genital HSV-2 DNA. Global agreement between the two serological assays was 86%. Concordance was high (99%) for sera that were negative by HerpeSelect or had high index values (>3.5). Defining infection detected by HSV-2 DNA PCR and/or Kalon assay as true infection, 71% of sera with low-positive index values were associated with true HSV-2 infection. Twenty-five women were identified as having nonprimary first-episode genital HSV-2 infection. Rates of HSV-2 seroconversion at day 14 were 77% (10/13 patients) by HerpeSelect assay and 23% (3/13 patients) by Kalon assay, with four additional seroconversions detected by Kalon assay at day 28. HIV serostatus did not influence assay performance. Low index values obtained with the HerpeSelect assay may correspond to true HSV-2 infection, in particular to nonprimary first episodes of genital HSV-2 infection, and need to be interpreted in the context of clinical history.

We studied the association between herpes simplex virus type-2 (HSV-2) and HIV-1 viralload in plasma, semen, cervico-vaginal secretions and genital ulcers. Forty-seven (68%) men and 57 (80%) women were HSV-2 antibody positive, of whom 12 (26%, 95% confidence interval [CI] 20, 32) and five (8%, 95% CI 4, 12), respectively, had HSV-2 genital shedding detected by polymerase chain reaction. The mean HIV-1 seminal and cervico-vaginal viral loads did not differ significantly according to the presence of HSV-2 shedding. Eleven men and 15 women presented with genital ulcers; all ulcers were due to HSV-2. Ten men and nine women were followed up over six days: the mean (95% CI) HIV-1 log viral load copies/mL in the genital ulcers at baseline and final visits were 2.5 (2.3, 2.7) and 3.1 (2.0, 4.2) for men and 3.0 (2.6, 3.4) and 2.7 (2.3, 3.1) for women. These findings do not support the hypothesis that HSV-2 increases the HIV-1 viral load in genital secretions.

Second-generation surveillance for HIV includes measures of high-risk behaviors among the general adult population and sex workers (SW). Questionnaires are prone to social desirability biases because individuals minimize the frequency of behaviors not expected from them. The objective was to determine whether the prostate-specific antigen (PSA) could be used as a biological marker of unprotected intercourse. We measured the presence of PSA in vaginal secretions of women who were (n = 508) or were not (n = 658) SW presenting with vaginal discharge in health facilities of Ghana Togo Guinea and Mali. The cutoff for a positive assay was determined as = 0.4 µg/L based on a subsample of 95 non-SW claiming abstinence for 3 months. A positive PSA assay was correlated with infections with Neisseria gonorrhoeae Chlamydia trachomatis and Mycoplasma genitalium. Among non-SW a positive PSA was more common among those with HIV but less frequent in those better educated. Among SW and non-SW women from Ghana were less likely to have a positive PSA and had a lower prevalence of sexually transmitted infections than those from elsewhere. PSA can be used as a biological marker of unprotected intercourse allowing interventions to target efforts on those at highest risk. (authors)

The accuracy and usefulness of laboratory-developed real-time PCR procedures using a Light Cycler instrument (Roche Diagnostics) for detecting and quantifying human immunodeficiency virus type 1 (HIV-1) RNA and DNA as well as herpes simplex virus type 1 (HSV-1)/HSV-2 DNA in cervicovaginal secretions from women coinfected with HIV and HSV were evaluated. For HIV-1, the use of the NEC152 and NEC131 primer set and the NEC-LTR probe in the long terminal repeat gene allowed us to detect accurately the majority of HIV-1 subtypes of group M circulating in sub-Saharan Africa, including subtypes A, B, C, D, and G as well as circulating recombinant forms 02 and 11. The detection threshold of real-time PCR for HIV in cervicovaginal lavage samples was 5 copies per assay for both RNA and DNA; the intra- and interassay coefficients of variation of C T values were 1.30% and 0.69% (HIV-1 RNA) and 1.84% and 0.67% (HIV-1 DNA), respectively. Real-time PCR for HSV using primers and probe targeting the HSV DNA polymerase gene allowed both detection and quantification of HSV DNA and also differentiation between HSV-1 and HSV-2 genotypes. The detection threshold of real-time PCR for HSV was 5 copies per assay; the intra- and interassay coefficients of variation of C T values were 0.96% and 1.49%, respectively. Both manual and automated silica-based procedures were appropriate for combined extraction of HIV and HSV genomes from female genital secretions. Taken together, these findings indicate that real-time PCR may be used as a unique nucleic acid amplification procedure to detect and quantify HIV and HSV genomes in cervicovaginal secretions and thus to assess at reduced costs the genital shedding of both viruses in women included in intervention studies.

Summary Background Toxins A and B are the primary virulence factors of Clostridium difficile . Since 2002, an epidemic of C difficile -associated disease with increased morbidity and mortality has been present in Quebec province, Canada. We characterised the dominant strain of this epidemic to determine whether it produces higher amounts of toxins A and B than those produced by non-epidemic strains. Methods We obtained isolates from 124 patients from Centre Hospitalier Universitaire de Sherbrooke in Quebec. Additional isolates from the USA, Canada, and the UK were included to increase the genetic diversity of the toxinotypes tested. Isolate characterisation included toxinotyping, pulsed-field gel electrophoresis (PFGE), PCR ribotyping, detection of a binary toxin gene, and detection of deletions in a putative negative regulator for toxins A and B ( tcdC ). By use of an enzyme-linked immunoassay, we measured the in-vitro production of toxins A and B by epidemic strain and non-dominant strain isolates. Findings The epidemic strain was characterised as toxinotype III, North American PFGE type 1, and PCR-ribotype 027 (NAP1/027). This strain carried the binary toxin gene cdtB and an 18-bp deletion in tcdC . We isolated this strain from 72 patients with C difficile -associated disease (58 [67%] of 86 with health-care-associated disease; 14 [37%] of 38 with community-acquired disease). Peak median (IQR) toxin A and toxin B concentrations produced in vitro by NAP1/027 were 16 and 23 times higher, respectively, than those measured in isolates representing 12 different PFGE types, known as toxinotype 0 (toxin A, median 848 μg/L [IQR 504–1022] vs 54 μg/L [23–203]; toxin B, 180 μg/L [137–210] vs 8 μg/L [5–25]; p Interpretation The severity of C difficile -associated disease caused by NAP1/027 could result from hyperproduction of toxins A and B. Dissemination of this strain in North America and Europe could lead to important changes in the epidemiology of C difficile -associated disease.

OBJECTIVE: To delineate the population attributable fraction (PAF) of transactional sex in prevalent cases of HIV infection in the male adult population of Accra, Ghana. DESIGN AND METHODS: Cross-sectional study of clients who visited a sex worker (SW), of boyfriends of SW and of male personnel in prostitution venues. A questionnaire was administered and urine obtained for detection of anti-HIV antibodies. The PAF of prevalent HIV acquired from SW was calculated using a combination of data from this survey of clients, from on-going SW surveys, the national HIV surveillance system and the national census. RESULTS: HIV prevalence was 4.9% (8/162) among clients of mobile SW, 15.8% (53/335) among clients of home-based SW, 17.5% (10/57) among personnel and 32.1% (9/28) among boyfriends. A condom was used in 90% of intercourses, according to clients. Non-use of a condom was clustered in selected locations and independently associated with older age of client, frequency of intercourse with SW in the last year and current urethritis. Among the male population of Accra aged 15-59 years, 84% of prevalent cases of HIV were attributable to transactional sex. A sensitivity analysis showed that under various assumptions PAF varied between 47% and 100%. CONCLUSIONS: In Accra, approximately four-fifths of prevalent cases of HIV in adult males were acquired from SW. Comprehensive interventions providing education, condoms and treatment for sexually transmitted diseases for SW and their clients should be approached as other public health priorities and provided in all cities, large and small, of West Africa.

Objectives: (1) To assess the frequency of influenza and influenza-like illness (ILI) during pregnancy; (2) to explore the associated risk of adverse maternal and fetal outcomes. Methods: All women who delivered at the Sherbrooke University Hospital in the province of Quebec during the period of February 15 to April 30, 2002, were invited to complete a questionnaire. Medical records of participating women and of their infants were reviewed. Complement-fixing antibody titres against influenza A were measured in paired sera drawn during antenatal screening and at delivery. Results: The study participation rate was 96. 3%. Nine of 517 women stated that they had received the influenza vaccine during pregnancy, and only 3 of 47 women with a chronic pulmonary disease had been immunized. Overall, 464 ILI episodes were reported by 331 women, and a significant maternal complication occurred in 8 cases. ILI episodes resulted in medical consultations in 55.4% of cases, and in antibiotic prescriptions in 13.8% of cases. There was no indication of an increased frequency of adverse perinatal outcomes associated with ILI during pregnancy. Paired sera were available for 156 participants and seroconversion was observed in 6.6%. Conclusions: ILI during pregnancy was associated with health services utilization but complications were infrequent. More studies are needed to demonstrate the usefulness of routine vaccination of healthy pregnant women against influenza.

Objectives: (1) To assess risk factors for urethral infections with Chlamydia trachomatis , Neisseria gonorrhoeae , and Trichomonas vaginalis among male clients of female sex workers (FSWs) in Benin; (2) to study the validity of LED testing of male urine samples compared to a highly sensitive gold standard (PCR) for the diagnosis of urethral infections with the organisms cited above. Methods: Male clients of FSWs (n=404) were recruited on site at prostitution venues in Cotonou, Benin, between 28 May and 18 August 1998. A urine sample was obtained from each participant just before he visited the FSW, and tested immediately using a leucocyte esterase dipstick (LED) test. It was then tested for HIV using the Calypte EIA with western blot confirmation, and for C trachomatis, N gonorrhoeae , and T vaginalis by PCR. After leaving the FSW’s room, participants were interviewed about demographics, sexual behaviour, STI history and current symptoms and signs, and were examined for urethral discharge, genital ulcers, and inguinal lymphadenopathies. Results: STI prevalences were: C trachomatis , 2.7%; N gonorrhoeae , 5.4%; either chlamydia or gonorrhoea 7.7%; T vaginalis 2.7%; HIV, 8.4%. Lack of condom use with FSWs and a history of STI were independently associated with C trachomatis and/or N gonorrhoeae infection. Over 80% of these infections were in asymptomatic subjects. The overall sensitivity, specificity, positive and negative predictive values of the LED test for detection of either C trachomatis or N gonorrhoeae were 48.4%, 94.9%, 44.1%, and 95.7%, respectively. In symptomatic participants (n=22), all these parameters were 100% while they were 47.4%, 94.7%, 37.5%, and 96.4% in asymptomatic men (n=304). Conclusions: Since most STIs are asymptomatic in this population, case finding programmes for gonorrhoea and chlamydia could be useful. The performance characteristics of the LED test in this study suggest that it could be useful to detect asymptomatic infection by either C trachomatis or N gonorrhoeae in high risk men.

The diagnostic performances of the clinical case definition of influenza virus infection based on the combination of fever and cough and of two rapid influenza diagnostic tests, the Directigen Flu A+B test (Directigen; BD Diagnostic Systems, Sparks, Md.) and the QuickVue influenza test (QuickVue; Quidel, San Diego, Calif.), were compared to those of viral culture and an in-house reverse transcription (RT)-PCR during the 2000-2001 flu season. Two hundred consecutive nasopharyngeal aspirates were analyzed from 192 patients, including 122 adults and 70 children. Viral culture identified influenza virus A in 16 samples and influenza virus B in 55 samples, whereas RT-PCR identified influenza virus A in 21 samples and influenza virus B in 64 samples. When RT-PCR was used as the reference standard, the likelihood ratios for a positive test were 40.0 for Directigen, 8.6 for QuickVue, and 1.4 for the combination of fever and cough, whereas the likelihood ratios for a negative test were 0.22, 0.16, and 0.48, respectively. Our study suggests that (i) the poor specificity (35 to 58%) and the poor positive predictive value (41 to 60%) of the clinical case definition of influenza preclude its use for prediction of influenza virus infections during epidemics, especially when infection control decision making in the hospital setting is considered; (ii) Directigen has a higher diagnostic yield than QuickVue but is associated with a larger number of invalid results; (iii) the sensitivities of the rapid diagnostic tests are significantly lower with samples from adults than with samples from children, with the rates of false-negative results reaching up to 29%; and (iv) RT-PCR detects more cases of influenza than viral culture, and this greater accuracy makes it a more useful reference standard.

Background: Syphilis remains a major cause of fetal loss and neonatal mortality in sub-Saharan Africa. Guinea-Bissau is the epicenter of the HIV-2 epidemic, and little is known about the impact of HIV-2 on pregnancy. Goal: To understand better the impact of maternal syphilis and HIV-2 on the outcomes of pregnancy in Bissau, Guinea-Bissau. Study Design: Using a case-control design, maternal syphilis and HIV-2 seropositive results were examined in relation to adverse outcomes of pregnancy. From June 1997 to April 1998, women presenting to the Simao Mendes hospital of Bissau for a delivery or a spontaneous abortion were invited to participate in the study, and 1341 women were enrolled. The 743 control subjects were women who had delivered a term neonate with a birthweight greater than 2500 g that survived the first 28 days of life. The cases were classified into five groups of mothers according to the outcome of pregnancy: stillbirths (n = 185), spontaneous abortions (n = 89), premature deliveries (n = 256), small-for-gestation-age babies (n = 55), and neonatal deaths (n = 13). Results: Among the control subjects, the prevalences of serologic syphilis and HIV infection were 3.9% and 7.9%, respectively. Positive syphilis serology results together with a rapid plasma reagin titer of 1:16 or more were associated with delivery of a stillborn (adjusted odds ratio [AOR], 6.05) and premature delivery (AOR, 2.98). In Bissau, the population-attributable risk fraction of syphilis was 7.2% (95% CI, 2.2-11.9%) for stillbirths and only 2.4% (95% CI, 0-5.8%) for premature deliveries. Spontaneous abortions, delivery of a small-for-gestation-age baby, and neonatal deaths were not associated with positive syphilis serology results. None of these pregnancy outcomes was significantly associated with HIV-2 infection. Conclusions: The effect of syphilis on the outcome of pregnancy in West Africa is similar to that reported from other parts of Africa. However, because the prevalence of positive syphilis serology results is relatively low, the impact of screening for syphilis on the outcome of pregnancy is likely to be relatively modest. The findings from this study confirm the absence of association between HIV-2 and an adverse pregnancy outcome.

An outbreak of Ebola virus disease (EVD) began in Guinea in December 2013, and by 21 November 2014, 15,531 cases had been identified with 5,429 associated deaths primarily in Guinea, Liberia, and Sierra Leone [1, 2]. Case fatality rates during the current outbreak are around 70 % among patients with known outcome [1]. As treatment options are limited and largely supportive, preventative measures are paramount in the control of this disease. Rapid and reliable diagnosis of EVD is critically important for patient management, infection prevention, and control measures, and optimization of use of healthcare resources. This article briefly reviews new developments in the diagnosis of EVD.

Background: Screening for cervical infection is difficult in developing countries. Screening strategies must be improved for high-risk women, such as female sex workers. Goal: To evaluate the sensitivity and specificity of screening algorithms for cervical infection pathogens among female sex workers in Accra, Ghana. Study Design: A cross-sectional study among female sex workers was conducted. Each woman underwent an interview and a clinical examination. Biologic samples were obtained for the diagnosis of HIV, syphilis, bacterial vaginosis, yeast infection, Trichomonas vaginalis, Neisseria gonorrhoeae, and Chlamydia trachomatis infection. Signs and symptoms associated with cervicitis agents were identified. Algorithms for the diagnosis of cervical infection were tested by computer simulations. Results: The following prevalences were observed: HIV, 76.6%; N gonorrhoeae, 33.7%; C trachomatis, 10.1%; candidiasis, 24.4%; T vaginalis, 31.4%; bacterial vaginosis, 2.3%; serologic syphilis, 4.6%; and genital ulcers on clinical examination, 10.6%. The best performance of algorithms were reached when using a combination of clinical signs and a search for gram-negative diplococci on cervical smears (sensitivity, 64.4%; specificity, 80.0%). Conclusions: In the algorithms, examination of Gram-stained genital smears in female sex workers without clinical signs of cervicitis improved sensitivity without altering specificity for the diagnosis of cervical infection.

International audience; Pseudomonas aeruginosa and Staphylococcus aureus are the most prevalent pathogens in airway infections of cystic fibrosis (CF) patients. We studied how these pathogens coexist and interact with each other. Clinical isolates of both species were retrieved from adult CF patients. Culture supernatants from 63 P. aeruginosa isolates triggered a wide range of biofilm-stimulatory activities when added to the culture of a control S. aureus strain. The extent of biofilm formation by S. aureus was positively correlated to the levels of the 2-alkyl-4-(1H)-quinolones (AQs) Pseudomonas Quinolone Signal (PQS) and 2-heptyl-4-hydroxy quinoline N-oxide (HQNO) produced by the P. aeruginosa isolates. Supernatants from P. aeruginosa isogenic mutants deficient in PQS and HQNO production stimulated significantly less biofilm formation by S. aureus than that seen with the parental strain PA14. When studying co-isolated pairs of P. aeruginosa and S. aureus retrieved from patients showing both pathogens, P. aeruginosa supernatants stimulated less biofilm production by the S. aureus counterparts compared to that observed using the control S. aureus strain. Accordingly, some P. aeruginosa isolates produced low levels of exoproducts and also some of the clinical S. aureus isolates were not stimulated by their co-isolates or by PA14 despite adequate production of HQNO. This suggests that colonization of the CF lungs promotes some type of strain selection, or that co-existence requires specific adaptations by either or both pathogens. Results provide insights on bacterial interactions in CF.

Campylobacter infection is a leading cause of bacterial gastroenteritis worldwide, and most clinical cases appear as isolated, sporadic infections for which the source is rarely apparent. From July 2005 to December 2007 we conducted a prospective case-case study of sporadic, domestically-acquired Campylobacter enteritis in rural versus urban areas and a prevalence study of Campylobacter in animal and environmental sources in the Eastern Townships, Quebec. Isolates were typed using Multilocus Sequence Typing (MLST) to reinforce the case-case findings and to assign a source probability estimate for each human isolate. The risk of human campylobacteriosis was 1.89-fold higher in rural than urban areas. Unconditional multivariate logistic regression analysis identified two independent risk factors associated with human Campylobacter infections acquired in rural area: occupational exposure to animals (OR = 10.6, 95% CI: 1.2-91, p = 0.032), and household water coming from a private well (OR = 8.3, 95% CI: 3.4-20.4, p

OBJECTIVES--Methods to quantitate Chlamydia trachomatis have never been compared although it would be relevant to periodically evaluate the sensitivity of a detection system. We compared the sensitivity and reproducibility of culture, direct immunofluorescence and the polymerase chain reaction (PCR) to quantitate C trachomatis. METHODS--A competitive semiquantitative PCR procedure was developed. The number of inclusions in culture, particles by direct immunofluorescence and DNA copies by PCR were measured for 12 patient specimens. Variation was determined by measuring a sample 10 times for each method. RESULTS--Patient C trachomatis major outer membrane protein gene DNA was measured semiquantitatively by amplifying together with reference DNA. DNA molecules, particles and infectious units were quantitated in clinical samples with, on average, 595 DNA molecules and 87 immunofluorescent particles observed per inclusion-forming-unit. Similar coefficients of variation (47-52%) were observed for the 3 procedures. CONCLUSION--Competitive PCR and counting immunofluorescent particles provide reproducible and sensitive methods of quantitating C trachomatis.

Staphylococcus aureus small-colony variants (SCVs) are persistent pathogenic bacteria characterized by slow growth and, for many of these strains, an increased ability to form biofilms and to persist within host cells. The virulence-associated gene expression profile of SCVs clearly differs from that of prototypical strains and is often influenced by SigB rather than by the agr system. One objective of this work was to confirm the role of SigB in the control of the expression of virulence factors involved in biofilm formation and intracellular persistence of SCVs. This study shows that extracellular proteins are involved in the formation of biofilm by three SCV strains, which, additionally, have a low biofilm-dispersing activity. It was determined that SigB activity modulates biofilm formation by strain SCV CF07-S and is dominant over that of the agr system without being solely responsible for the repression of proteolytic activity. On the other hand, the expression of fnbA and the control of nuclease activity contributed to the SigB-dependent formation of biofilm of this SCV strain. SigB was also required for the replication of CF07-S within epithelial cells and may be involved in the colonization of lungs by SCVs in a mouse infection model. This study methodically investigated SigB activity and associated mechanisms in the various aspects of SCV pathogenesis. Results confirm that SigB activity importantly influences the production of virulence factors, biofilm formation and intracellular persistence for some clinical SCV strains.

Chlamydia trachomatis can be directly transmitted by sexual or perinatal contact and indirectly transmitted by flies or fomites. Whether distinct epidemiologic forces among human populations or biologic characteristics of the organism are responsible for the different routes of transmission is uncertain.To determine if ophthalmia neonatorum and trachoma are linked epidemiologically, 38 infants with ophthalmia and 277 children with trachoma were studied for evidence of C. trachomatis infection using culture, antigen and DNA detection tests. The study was performed in a trachoma endemic area of central Kenya.Of infants with ophthalmia neonatorum, 8% to 9% had microbiologic evidence of ocular C. trachomatis infection. Of the children with trachoma, 31% had evidence of chlamydial infection. Ninety-two percent of the 59 identified strains causing trachoma belonged to the classic trachoma serovars (A, B, Ba and C). Neither of the two chlamydial strains recovered from infants with ophthalmia was a trachoma serovar. Mothers rarely (3%) had cervical C. trachomatis infection.This study does not support a major role for perinatally transmitted C. trachomatis infection in trachoma epidemiology.Chlamydia trachomatis can be directly transmitted by sexual or perinatal contact and indirectly by flies or fomites. To determine if ophthalmia neonatorum and trachoma are linked epidemiologically, 38 infants with ophthalmia (mean age of 1.8 +or- 2.5 months) and 277 children with trachoma (3 months - 14 years old) were studied for evidence of C trachomatis infection using culture, antigen, and DNA detection tests. The study was performed in a trachoma endemic area in 2 rural health centers (Lare and Mutuwati) in the Meru District in central Kenya over a 2 1/2-year period between 1988-1991. 29 mothers of the 38 infants had tests for cervical C. trachomatis infection. 53 children with trachomatous inflammation (follicular) (TF) and 224 children with trachoma inflammation (intense) with or without TF were enrolled. Subjects were classified according to the World Health Organization trachoma grading scheme. 167 mothers of these 277 children were examined for evidence of cervical C trachomatis infection. Of infants with ophthalmia neonatorum, 8-9% had microbiologic evidence of ocular G trachomatis infection. Of the children with trachoma, 31% had evidence of chlamydial infection. 92% of the 59 identified strains causing trachoma belonged to the classic trachoma serovars (A, B, Ba and C). 3% of mothers had cervical C trachomatis infection. Among children with trachoma, 10% had positive ocular cultures for C. trachomatis, 24 had positive EIA tests, and 31% had positive PCR tests. Among infants with ophthalmia neonatorum, evidence of C. trachomatis infection was rare. 9% (2 of 22) had positive EIA tests, and 8% (2 of 26) had positive PCR tests. Among the mothers of children with trachoma, 3% had positive C. trachomatis cervical cultures and 2% had positive EIA tests. No mother of an infant with ophthalmia neonatorum had positive cervical tests for C. trachomatis. There was no evidence of a major role for perinatally transmitted C trachomatis infection in trachoma epidemiology.

Background Oral vancomycin (125 mg qid) is recommended as treatment of severe Clostridium difficile infection (CDI). Higher doses (250 or 500 mg qid) are sometimes recommended for patients with very severe CDI, without supporting clinical evidence. We wished to determine to what extent faecal levels of vancomycin vary according to diarrhoea severity and dosage, and whether it is rational to administer high-dose vancomycin to selected patients. Methods We recruited hospitalized adults suspected to have CDI for whom oral vancomycin (125, 250 or 500 mg qid) had been initiated. Faeces were collected up to 3 times/day and levels were measured with the AxSYM fluorescence polarization immunoassay. Results Fifteen patients (9 with confirmed CDI) were treated with oral vancomycin. Patients with ≥4 stools daily presented lower faecal vancomycin levels than those with a lower frequency. Higher doses of oral vancomycin (250 mg or 500 mg qid) led to consistently higher faecal levels (> 2000 mg/L), which were 3 orders of magnitude higher than the MIC90 of vancomycin against C. difficile. One patient receiving 125 mg qid had levels below 50 mg/L during the first day of treatment. Conclusions Faecal levels of vancomycin are proportional to the dosage administered and, even in patients with increased stool frequency, much higher than the MIC90. Patients given the standard 125 mg qid dosage might have low faecal levels during the first day of treatment. A loading dose of 250 mg or 500 mg qid during the first 24-48 hours followed by the standard dosage should be evaluated in larger studies, since it might be less disruptive to the colonic flora and save unnecessary costs.

International audience; BACKGROUND: The simultaneous emergence of human immunodeficiency virus (HIV)-1 group M and HIV-2 into human populations, circa 1921-1940, is attributed to urbanization and changes in sexual behavior. We hypothesized that the initial dissemination of HIV-1, before sexual transmission predominated, was facilitated by the administration, via reusable syringes and needles, of parenteral drugs against tropical diseases. As proxies for highly lethal HIV-1, we investigated risk factors for hepatitis C virus (HCV) and human T cell lymphotropic virus 1 (HTLV-1) infections, blood-borne viruses compatible with prolonged survival, in an area known in 1936-1950 as the most virulent focus of African trypanosomiasis. METHODS: Cross-sectional survey of individuals 55 years and older in Mbimou land and Nola, Central African Republic. Dried blood spots were used for HCV and HTLV-1 serologic testing and nucleic acid detection. Adjusted odds ratios (ORs) and 95% confidence intervals (CIs) were measured by logistic regression. RESULTS: The only risk factor for HCV genotype 4 infection was treatment of trypanosomiasis before 1951 (OR, 3.13; 95% CI, 1.38-7.09). HTLV-1 infection was associated with having received 2 injections of pentamidine for trypanosomiasis chemoprophylaxis (adjusted OR, 2.03; 95% CI, 1.01-4.06) and with transfusions (adjusted OR, 2.82; 95% CI, 1.04-7.67). From historical data, we predicted that 59% of Mbimous 65 years and older would report treatment for trypanosomiasis before 1951; only 11% did so. CONCLUSIONS: Treatment of trypanosomiasis before 1951 may have caused iatrogenic HCV transmission. Population-wide half-yearly intramuscular pentamidine for trypanosomiasis chemoprophylaxis in 1947-1953 may have caused iatrogenic HTLV-1 transmission. These and other interventions against tropical diseases could have iatrogenically transmitted SIV(cpz), jump-starting the HIV-1 epidemic. The excess mortality among patients with trypanosomiasis treated before 1951 supports this hypothesis.

The molecular epidemiology of hepatitis C virus (HCV) in the Central African Republic (CAR) is poorly documented. Thus, we conducted phylogenetic analyses of NS5B gene sequences from 58 HCV-infected inhabitants of a remote area of south-west CAR, which indicated that 48 (82.8 %) were infected with genotype 4 (HCV-4), five (8.6 %) with genotype 2 and five (8.6 %) with genotype 1. HCV-4 strains were highly heterogeneous, containing previously described subtypes 4k (48 %), 4c (27 %), 4r (4 %), 4f (4 %) and unclassified subtypes (17 %). To estimate the epidemic history of these HCV-4 strains, an evolutionary analysis using the coalescent approach was used. The estimated date of the most recent common ancestor of the CAR HCV-4 strains was 1539 (95 % confidence intervals, 1317–1697). They exhibited a rapid, exponential spread from 1935 to 1965, simultaneously with what was recently reported in neighbouring Cameroon and Gabon. The hypothesis of a massive iatrogenic transmission during interventions for the control of endemic tropical diseases is discussed.

BACKGROUND: Little is known about the impact of episodic treatment of herpes on human immunodeficiency virus type 1 (HIV-1). METHODS: Women from Ghana and the Central African Republic who had genital ulcers were enrolled in a randomized double-blind placebo-controlled trial of acyclovir plus antibacterials and were monitored for 28 days. Ulcer etiologies and detection of lesional HIV-1 RNA were determined by polymerase chain reaction (PCR). Cervicovaginal HIV-1 RNA and herpes simplex virus type 2 (HSV-2) DNA and plasma HIV-1 RNA were quantitated by real-time PCR. Primary analyses included 118 HIV-1-infected women with HSV-2 ulcers (54 of whom were given acyclovir and 64 of whom were given placebo). RESULTS: Acyclovir had little impact on (1) detection of cervicovaginal HIV-1 RNA (risk ratio [RR] 0.96; 95% confidence interval [CI] 0.8-1.2) at day 7 of treatment (2) the mean cervicovaginal HIV-1 RNA load (-0.06 log(10) copies/mL; 95% CI -0.4 to 0.3 log(10) copies/mL) at day 7 of treatment or (3) the plasma HIV-1 RNA load (+0.09 log(10) copies/mL; 95% CI -0.1 to 0.3 log(10) copies/mL) at day 14 of treatment. At day 7 women receiving acyclovir were less likely to have detectable lesional HIV-1 RNA (RR 0.70; 95% CI 0.4-1.2) or cervicovaginal HSV-2 DNA (RR 0.69; 95% CI 0.4-1.3) had a lower quantity of HSV-2 DNA (-0.99 log(10) copies/mL; 95% CI -1.8 to -0.2 log(10) copies/mL) and were more likely to have a healed ulcer (RR 1.26; 95% CI 0.9-1.9). CONCLUSION: Episodic therapy for herpes reduced the quantity of cervicovaginal HSV-2 DNA and slightly improved ulcer healing but it did not decrease genital and plasma HIV-1 RNA loads. TRIAL REGISTRATION: ClinicalTrials.gov identifier NCT00158483 .

Understanding the origin and nature of hepatitis C virus (HCV) genetic diversity is critical for improving treatment and vaccine design, and such diversity is the sole source of information about the virus' epidemic history prior to its identification 20 years ago. In this paper, we study the molecular epidemiology of HCV genotype 2 in its region of endemic origin, west and central Africa. Our analysis includes 56 new and highly diverse HCV isolates sampled from infected individuals in Guinea-Bissau. By combining phylogenetic, geographical and epidemiological information, we find a previously unappreciated geographical structure in the diversity of HCV genotype 2, pointing to a history of eastwards spatial spread from the west African coast to Cameroon that took place over several centuries. Molecular clock analysis dates the common ancestor of HCV in Guinea-Bissau to 1470 (1414-1582). The phylogenetic position of isolates from Madagascar and Martinique suggests a role for the historical slave trade in the global dissemination of HCV and of the epidemic subtypes 2a and 2c. Coalescent-based estimates of epidemic growth indicate a rapid 20th-century spread of HCV genotype 2 in Cameroon that is absent in Guinea-Bissau. We discuss this contrast in the context of possible parenteral HCV exposure during public-health campaigns undertaken during the colonial era.

OBJECTIVE: To describe the epidemiology of HIV among core groups in Togo. METHODS: We enumerated sex workers (SWs) and conducted cross-sectional surveys of SWs and their clients in 2003 in Lome and in 2005 in the whole country. RESULTS: Sex work was concentrated in Lome which comprised 15% of the population but 52% of the 5397 SWs enumerated in Togo in 2005 and 68% of the estimated 101376 men who had bought sex in the year before the 2005 survey. HIV prevalence among SWs was highest in Lome (45.4% in 2005) and progressively decreased from south to north. A similar geographical pattern was seen for clients (8.3% were HIV infected in Lome in 2005) and had already been reported for pregnant women. In Lome the population attributable fraction of prevalent cases of HIV acquired during transactional sex was estimated at 32%; in the rest of the country this was only 2%. CONCLUSIONS: This is the first study quantifying sex work at a national level in Africa. Variations in HIV prevalence within Togo with a north-south gradient among SWs their clients and pregnant women may to a large extent reflect the concentration of the sex trade within Lome. Prostitution played only a modest a role in HIV dynamics outside Lome.

Molecular strain typing is essential for deciphering the epidemiology of Campylobacter jejuni infections. We applied two different methods, multilocus sequence typing (MLST) and analysis of the flaA short variable repeat (SVR), to 289 isolates (163 human, 56 chicken, 34 raw milk, and 36 environmental water isolates) collected in the province of Québec, Canada, over 3 years; in addition, the analysis included the pulsed-field gel electrophoresis (PFGE) typing results for a subset of 131 isolates studied previously. MLST defined 96 sequence types (STs) and 20 clonal complexes (CCs), including 49 STs (73 isolates, 25%) and 39 alleles not previously documented in an international database. The frequency of new STs was significantly higher among water isolates than among isolates from other sources (18/36 [50%] and 55/253 [22%], respectively; P < 0.001). Nine of the 10 most prevalent CCs included isolates from humans and at least one other source; five CCs comprised exclusively or mostly human and chicken isolates. However, water and milk were the predominant nonhuman sources among the remaining CCs, suggesting that sporadic C. jejuni infections in humans may frequently arise from sources other than chickens. All three typing systems were discriminatory (discriminatory index > 0.9). Among 131 isolates analyzed by PFGE, each of the 20 types represented by two or more isolates corresponded to a single CC. In contrast, among the 14 most prevalent types detected by analysis of the flaA SVR (5 to 27 isolates each), 8 (57%) included isolates that represented multiple different CCs. The basis for these discordant results was uncertain. Antimicrobial resistance was randomly distributed among the CCs and appeared to be more closely related to the source of an isolate than its genotype. Although MLST is labor-intensive and expensive, it remains the single best method for the genotyping of C. jejuni isolates and deciphering the epidemiologic relationships among isolates.

In 1957, Chlamydia trachomatis (non-genital serovars A, B, Ba and C) was recognized as the aetiological agent of trachoma.1 C trachomatis genital serovars D to K cause ophthalmia neonatorum and conjunctivitis in older children and adults. Trachoma remains endemic in many countries of sub-Saharan Africa, the Middle East and other areas of the developing world.2 Nucleic acid amplification testing (NAAT) represented a major advance in the diagnosis of C trachomatis infection among patients with trachoma, cell culture being rarely available in endemic countries. Even using this most sensitive technology, however, one fifth of patients with severe trachoma and up to one half of those with milder infections do not have …

The combination of high sexually transmitted infection (STI) prevalence and low HIV prevalence has been described as the Indian Ocean paradox. To investigate current epidemiology of HIV and STI in the Comoros, we conducted cross-sectional surveys of a representative sample of the adult population, and convenience samples of female sex workers and male STI patients. Only one (0.025%) of 3990 community participants was HIV-infected, while 142 (3.6%) had treponemal antibodies. Treponemal antibodies were not associated with past genital ulcers, number of sexual partners or adverse outcomes of pregnancies; their prevalence did not increase with age and there was no concordance within couples. Thus, most individuals with treponemal antibodies were probably infected during childhood with a non-venereal treponematosis. Only 1/70 (1.4%) and 0/83 sex workers sampled in 2004 and 2005 were HIV-infected. The Comoros have been protected by their insular status, male circumcision and paucity of syphilis. HIV control should focus on sex workers.

OBJECTIVE:: To investigate correlates of herpes simplex virus type 2 (HSV-2) DNA and HIV-1 RNA among women with genital ulcer disease (GUD). DESIGN:: Baseline data from a randomized placebo-controlled trial of episodic herpes treatment in Ghana and the Central African Republic. METHODS:: GUD aetiology was determined by polymerase chain reaction (PCR) from a lesional swab. Real-time PCR was used to quantify HIV-1 RNA, and HSV-2 DNA in cervicovaginal lavages (CVL) and HIV-1 RNA in plasma. Genital infection was defined as the presence of virus in the lesion or CVL. RESULTS:: Of 441 women enrolled, 79.0% were HSV-2 seropositive, 46.6% were HIV-1 seropositive, and 50.0% had an HSV-2 ulcer. Among 180 HSV-2/HIV-1 co-infected women, cervicovaginal HIV-1 RNA was detected more frequently in women with HSV-2 ulcers (67.9%) or cervicovaginal HSV-2 DNA only (72.3%) compared with women without genital HSV-2 infection (42.4%) (P = 0.004). Women with genital HSV-2 infection had higher median cervicovaginal HIV-1-RNA loads (3.14 log10 copies/mL versus 2.10 log10 copies/mL; P = 0.003), higher plasma HIV-1-RNA loads (median 5.10 versus 4.65 log10 copies/mL; P = 0.07), and lower median CD4 cell counts) (198 versus 409 cells/mm, P = 0.03). Cervicovaginal HIV-1 RNA and HSV-2 DNA were significantly correlated after adjusting for plasma HIV-1 RNA and CD4 cell counts (P < 0.001) and a 10-fold increase in cervicovaginal HSV-2 DNA was associated with a 1.7-fold increase in plasma HIV-1 RNA (P = 0.003). CONCLUSION:: Genital HSV-2 infection is associated with increased cervicovaginal and plasma HIV-1 RNA among co-infected women with genital ulcers, independently of the level of immunodeficiency, highlighting the close interaction between these two viruses and the role of HSV-2 as a co-factor for the sexual transmission of HIV-1.

This study compares the occurrence of antimicrobial resistance to erythromycin, ciprofloxacin, and tetracycline among 384 Campylobacter jejuni isolates from humans (245), fresh whole retail chickens (56), raw milk (33), and environmental water (41) collected between 2000 and 2003 in Quebec, Canada. Resistance to ciprofloxacin was significantly more frequent in human isolates acquired abroad than in those acquired locally (50 versus 5.9%; P < 0.001); ciprofloxacin resistance was almost absent in water, chicken, and raw milk isolates. In contrast, resistance to erythromycin was significantly more common in chicken than in locally acquired human isolates (16 versus 3.0%, respectively; P < 0.001); no erythromycin resistance was found among water, raw milk, and human isolates acquired abroad. Resistance to tetracycline was significantly more common in chicken and human isolates acquired locally (58.9 and 45.8%, respectively) than in raw milk and water isolates (9.1 and 7.3%, respectively, P < 0.001). Tetracycline resistance was also observed in 44.4% of human isolates acquired abroad. No human isolate was resistant to both ciprofloxacin and erythromycin, but one chicken isolate was resistant to all three antimicrobial agents. Our results suggest that from 2000 to 2003 in Quebec, antimicrobial resistance remained stable among locally acquired C. jejuni human clinical isolates and might even have decreased. However, the high erythromycin resistance rate observed among chicken isolates is concerning because of the risk of transmission of such isolates to humans. Additional studies are needed to monitor trends in antimicrobial resistance among food, environment, and human C. jejuni isolates as well as antibiotic use in animals.

Clinical and subclinical genital herpes simplex virus type 2 (HSV-2) reactivations have been associated with increases in human immunodeficiency virus (HIV)-1 genital shedding. Whether HSV-2 shedding contributes to the selection of specific genital HIV-1 variants remains unknown. We evaluated the genetic diversity of genital and blood HIV-1 RNA and DNA in 14 HIV-1/HSV-2-co-infected women, including seven with HSV-2 genital reactivation, and seven without as controls. HIV-1 DNA and HIV-1 RNA env V1–V3 sequences in paired blood and genital samples were compared. The HSV-2 selection pressure on HIV was estimated according to the number of synonymous substitutions (dS), the number of non-synonymous substitutions (dN) and the dS/dN ratio within HIV quasi-species. HIV-1 RNA levels in cervicovaginal secretions were higher in women with HSV-2 replication than in controls (p0.02). Plasma HIV-1 RNA and genital HIV-1 RNA and DNA were genetically compartmentalized. No differences in dS, dN and the dS/dN ratio were observed between the study groups for either genital HIV-1 RNA or plasma HIV-1 RNA. In contrast, dS and dN in genital HIV-1 DNA were significantly higher in patients with HSV-2 genital reactivation (p

OBJECTIVE: To evaluate whether single-dose treatments are as effective as standard therapy in the syndromic management of vaginal discharge. METHODS: A randomized controlled effectiveness trial compared single-dose tinidazole plus fluconazole (TF) with treatment for 7 days with metronidazole plus 3 days of treatment with vaginal clotrimazole (MC) among 1570 women presenting with vaginal discharge at primary health care institutions in Ghana, Guinea, Mali and Togo. Participants were randomly allocated to one of the two treatments by research nurses or physicians using precoded envelopes. Effectiveness was assessed by symptomatic response on day 14. CLINICAL IDENTIFIER ClinicalTrials.gov NCT00313131. FINDINGS: The two treatment regimens had similar effectiveness: complete resolution was seen in 66% (TF) and 64% (MC) and partial resolution in 33% (TF) and 34% (MC) of participants (P = 0.26). Effectiveness was similar among subgroups with vulvovaginal candidiasis, Trichomonas vaginalis vaginitis or bacterial vaginosis. The two treatment regimens had a similar effectiveness among human immunodeficiency virus (HIV)-infected (TF: n = 76, 71% complete resolution, 28% partial; MC: n = 83, 72% complete resolution, 25% partial, P = 0.76) and HIV-uninfected women (TF: n = 517, 68% complete, 32% partial; MC: n = 466, 65% complete, 33% partial, P = 0.20). Cervical infections with Neisseria gonorrhoeae, Chlamydia trachomatis and Mycoplasma genitalium were uncommon among women not involved in sex work, were associated with bacterial vaginosis or T. vaginalis vaginitis, and did not alter response to treatment with agents active against vaginal infections. Four-fifths of women not relieved by a single dose of TF had a favourable response when MC was administered as second-line treatment. CONCLUSION: Single-dose TF is as effective as multiple-dose MC in the syndromic management of vaginal discharge, even among women with HIV-infection. Given its low price and easier adherence, TF should be considered as a first-line treatment for vaginal discharge syndrome.

Objectives: To identify the contribution of Mycoplasma genitalium to the aetiology of cervicitis in sub-Saharan Africa and its relative importance in the overall burden of sexually transmitted infections among female sex workers (FSW). Methods: The study population consisted of FSW recruited in Ghana and Benin during the initial visit of a randomised controlled trial. A questionnaire was administered, a pelvic examination carried out, and cervical samples obtained for detection of M genitalium, Neisseria gonorrhoeae, Chlamydia trachomatis, and Trichomonas vaginalis. Clinical signs potentially indicating cervicitis were cervical discharge, pus on the cervical swab, bleeding after sampling, and inflammatory cervix. Results: Among 826 FSW, 26.3% were infected with M genitalium. N gonorrhoeae was strongly and independently associated with each of the four signs of cervicitis (adjusted odds ratios (AOR): 4.1 to 6.0). The AOR for C trachomatis were intermediate (1.3–4.1) and the AOR for M genitalium were lower (between 1.6 and 1.8) but statistically significant (p⩽0.05) for each sign. Conclusions:M genitalium is weakly associated with signs of cervicitis in west African FSW but is highly prevalent.