Simple Estimation of Incident HIV Infection Rates in Notification Cohorts Based on Window Periods of Algorithms for Evaluation of Line-Immunoassay Result Patterns

Background Tests for recent infections (TRIs) are important for HIV surveillance. We have shown that a patient's antibody pattern in a confirmatory line immunoassay (Inno-Lia) also yields information on time since infection. We have published algorithms which, with a certain sensitivity and specificity, distinguish between incident (< = 12 months) and older infection. In order to use these algorithms like other TRIs, i.e., based on their windows, we now determined their window periods. Methods We classified Inno-Lia results of 527 treatment-naïve patients with HIV-1 infection < = 12 months according to incidence by 25 algorithms. The time after which all infections were ruled older, i.e. the algorithm's window, was determined by linear regression of the proportion ruled incident in dependence of time since infection. Window-based incident infection rates (IIR) were determined utilizing the relationship ‘Prevalence = Incidence x Duration’ in four annual cohorts of HIV-1 notifications. Results were compared to performance-based IIR also derived from Inno-Lia results, but utilizing the relationship ‘incident = true incident + false incident’ and also to the IIR derived from the BED incidence assay. Results Window periods varied between 45.8 and 130.1 days and correlated well with the algorithms' diagnostic sensitivity (R2 = 0.962; P<0.0001). Among the 25 algorithms, the mean window-based IIR among the 748 notifications of 2005/06 was 0.457 compared to 0.453 obtained for performance-based IIR with a model not correcting for selection bias. Evaluation of BED results using a window of 153 days yielded an IIR of 0.669. Window-based IIR and performance-based IIR increased by 22.4% and respectively 30.6% in 2008, while 2009 and 2010 showed a return to baseline for both methods. Conclusions IIR estimations by window- and performance-based evaluations of Inno-Lia algorithm results were similar and can be used together to assess IIR changes between annual HIV notification cohorts.

Additive effects of HLA alleles and innate immune genes determine viral outcome in HCV infection

BACKGROUND Chronic HCV infection is a leading cause of liver-related morbidity globally. The innate and adaptive immune responses are thought to be important in determining viral outcomes. Polymorphisms associated with the IFNL3 (IL28B) gene are strongly associated with spontaneous clearance and treatment outcomes. OBJECTIVE This study investigates the importance of HLA genes in the context of genetic variation associated with the innate immune genes IFNL3 and KIR2DS3. DESIGN We assess the collective influence of HLA and innate immune genes on viral outcomes in an Irish cohort of women (n=319) who had been infected from a single source as well as a more heterogeneous cohort (Swiss Cohort, n=461). In the Irish cohort, a number of HLA alleles are associated with different outcomes, and the impact of IFNL3-linked polymorphisms is profound. RESULTS Logistic regression was performed on data from the Irish cohort, and indicates that the HLA-A*03 (OR 0.36 (0.15 to 0.89), p=0.027) -B*27 (OR 0.12 (0.03 to 0.45), p=<0.001), -DRB1*01:01 (OR 0.2 (0.07 to 0.61), p=0.005), -DRB1*04:01 (OR 0.31 (0.12 to 0.85, p=0.02) and the CC IFNL3 rs12979860 genotypes (OR 0.1 (0.04 to 0.23), p<0.001) are significantly associated with viral clearance. Furthermore, DQB1*02:01 (OR 4.2 (2.04 to 8.66), p=0.008), KIR2DS3 (OR 4.36 (1.62 to 11.74), p=0.004) and the rs12979860 IFNL3 'T' allele are associated with chronic infection. This study finds no interactive effect between IFNL3 and these Class I and II alleles in relation to viral clearance. There is a clear additive effect, however. Data from the Swiss cohort also confirms independent and additive effects of HLA Class I, II and IFNL3 genes in their prediction of viral outcome. CONCLUSIONS This data supports a critical role for the adaptive immune response in the control of HCV in concert with the innate immune response.

Higher plant diversity promotes higher diversity of fungal pathogens, while it decreases pathogen infection per plant

Fungal plant pathogens are common in natural communities where they affect plant physiology, plant survival, and biomass production. Conversely, pathogen transmission and infection may be regulated by plant community characteristics such as plant species diversity and functional composition that favor pathogen diversity through increases in host diversity while simultaneously reducing pathogen infection via increased variability in host density and spatial heterogeneity. Therefore, a comprehensive understanding of multi-host multi-pathogen interactions is of high significance in the context of biodiversity-ecosystem functioning. We investigated the relationship between plant diversity and aboveground obligate parasitic fungal pathogen (''pathogens'' hereafter) diversity and infection in grasslands of a long-term, large-scale, biodiversity experiment with varying plant species (1-60 species) and plant functional group diversity (1-4 groups). To estimate pathogen infection of the plant communities, we visually assessed pathogen-group presence (i.e., rusts, powdery mildews, downy mildews, smuts, and leaf-spot diseases) and overall infection levels (combining incidence and severity of each pathogen group) in 82 experimental plots on all aboveground organs of all plant species per plot during four surveys in 2006. Pathogen diversity, assessed as the cumulative number of pathogen groups on all plant species per plot, increased log-linearly with plant species diversity. However, pathogen incidence and severity, and hence overall infection, decreased with increasing plant species diversity. In addition, co-infection of plant individuals by two or more pathogen groups was less likely with increasing plant community diversity. We conclude that plant community diversity promotes pathogen-community diversity while at the same time reducing pathogen infection levels of plant individuals.

Use of early corticosteroid therapy on ICU admission in patients affected by severe pandemic (H1N1)v influenza A infection.

INTRODUCTION Early use of corticosteroids in patients affected by pandemic (H1N1)v influenza A infection, although relatively common, remains controversial. METHODS Prospective, observational, multicenter study from 23 June 2009 through 11 February 2010, reported in the European Society of Intensive Care Medicine (ESICM) H1N1 registry. RESULTS Two hundred twenty patients admitted to an intensive care unit (ICU) with completed outcome data were analyzed. Invasive mechanical ventilation was used in 155 (70.5%). Sixty-seven (30.5%) of the patients died in ICU and 75 (34.1%) whilst in hospital. One hundred twenty-six (57.3%) patients received corticosteroid therapy on admission to ICU. Patients who received corticosteroids were significantly older and were more likely to have coexisting asthma, chronic obstructive pulmonary disease (COPD), and chronic steroid use. These patients receiving corticosteroids had increased likelihood of developing hospital-acquired pneumonia (HAP) [26.2% versus 13.8%, p < 0.05; odds ratio (OR) 2.2, confidence interval (CI) 1.1-4.5]. Patients who received corticosteroids had significantly higher ICU mortality than patients who did not (46.0% versus 18.1%, p < 0.01; OR 3.8, CI 2.1-7.2). Cox regression analysis adjusted for severity and potential confounding factors identified that early use of corticosteroids was not significantly associated with mortality [hazard ratio (HR) 1.3, 95% CI 0.7-2.4, p = 0.4] but was still associated with an increased rate of HAP (OR 2.2, 95% CI 1.0-4.8, p < 0.05). When only patients developing acute respiratory distress syndrome (ARDS) were analyzed, similar results were observed. CONCLUSIONS Early use of corticosteroids in patients affected by pandemic (H1N1)v influenza A infection did not result in better outcomes and was associated with increased risk of superinfections.

Developmental oestrogen exposure differentially modulates IGF-I and TNF-α expression levels in immune organs of Yersinia ruckeri-challenged young adult rainbow trout (Oncorhynchus mykiss).

Intensified aquaculture has strong impact on fish health by stress and infectious diseases and has stimulated the interest in the orchestration of cytokines and growth factors, particularly their influence by environmental factors, however, only scarce data are available on the GH/IGF-system, central physiological system for development and tissue shaping. Most recently, the capability of the host to cope with tissue damage has been postulated as critical for survival. Thus, the present study assessed the combined impacts of estrogens and bacterial infection on the insulin-like growth factors (IGF) and tumor-necrosis factor (TNF)-α. Juvenile rainbow trout were exposed to 2 different concentrations of 17β-estradiol (E2) and infected with Yersinia ruckeri. Gene expressions of IGF-I, IGF-II and TNF-α were measured in liver, head kidney and spleen and all 4 estrogen receptors (ERα1, ERα2, ERβ1 and ERβ2) known in rainbow trout were measured in liver. After 5 weeks of E2 treatment, hepatic up-regulation of ERα1 and ERα2, but down-regulation of ERß1 and ERß2 were observed in those groups receiving E2-enriched food. In liver, the results further indicate a suppressive effect of Yersinia-infection regardless of E2-treatment on day 3, but not of E2-treatment on IGF-I whilst TNF-α gene expression was not influenced by Yersinia-infection but was reduced after 5 weeks of E2-treatment. In spleen, the results show a stimulatory effect of Yersinia-infection, but not of E2-treatment on both, IGF-I and TNF-α gene expressions. In head kidney, E2 strongly suppressed both, IGF-I and TNF-α. To summarise, the treatment effects were tissue- and treatment-specific and point to a relevant role of IGF-I in infection.

Babesia spp. in European wild ruminant species: parasite diversity and risk factors for infection.

Babesia are tick-borne parasites that are increasingly considered as a threat to animal and public health. We aimed to assess the role of European free-ranging wild ruminants as maintenance mammalian hosts for Babesia species and to determine risk factors for infection. EDTA blood was collected from 222 roe deer (Capreolus c. capreolus), 231 red deer (Cervus e. elaphus), 267 Alpine chamois (Rupicapra r. rupicapra) and 264 Alpine ibex (Capra i. ibex) from all over Switzerland and analysed by PCR with pan-Babesia primers targeting the 18S rRNA gene, primers specific for B. capreoli and Babesia sp. EU1, and by sequencing. Babesia species, including B. divergens, B. capreoli, Babesia sp. EU1, Babesia sp. CH1 and B. motasi, were detected in 10.7% of all samples. Five individuals were co-infected with two Babesia species. Infection with specific Babesia varied widely between host species. Cervidae were significantly more infected with Babesia spp. than Caprinae. Babesia capreoli and Babesia sp. EU1 were mostly found in roe deer (prevalences 17.1% and 7.7%, respectively) and B. divergens and Babesia sp. CH1 only in red deer. Factors significantly associated with infection were low altitude and young age. Identification of Babesia sp. CH1 in red deer, co-infection with multiple Babesia species and infection of wild Caprinae with B. motasi and Babesia sp. EU1 are novel findings. We propose wild Caprinae as spillover or accidental hosts for Babesia species but wild Cervidae as mammalian reservoir hosts for B. capreoli, possibly Babesia sp. EU1 and Babesia sp. CH1, whereas their role regarding B. divergens is more elusive.

Molecular Epidemiology Issues of BVDV Infection in the Eastern Ukraine

Aim. This study was focused on (i) detection of specific BVDV-antibodies within selected cattle farms, (ii) identification of persistently infected (PI) animals and (iii) genetic typing of selected BVDV isolates. Methods. RNA extraction, real-time polymerase chain reaction, ELISA technique, sequencing. Results. Specific BVDV-antibodies were detected in 713 of 1,059 analyzed samples (67.3 per cent). This number is in agreement with findings in many cattle herds around the world. However, the number of positive samples differed in the herds. While 57 samples out of 283 (20.1 per cent) were identified in the first herd, 400 out of 475 (84.2 per cent) and 256 out of 301 (85 per cent) animals were positive in the second and third herd. High number of animals with BVDV RNA was detected in all herds. The real-time PCR assay detected BVDV RNA in 5 of 1068 samples analyzed (0.5 per cent). 4 positive samples out of 490 (0.8 per cent) and 1 out of 301 (0.33 per cent) were found in the second and third herd. The genetic materials of BVDV were not found in the first herd. Data on the number of PI animals were in accord with serological findings in the cattle herds involved in our study. The genetic typing of viral isolates revealed that only BVDV, Type 1 viruses were present. The hylogenetic analysis confirmed two BVDV-1 subtypes, namely b and f and revealed that all 4 viruses from the second farm were typed as BVDV-1b and all of them were absolutely identical in 5’-UTR, but virus from the third farm was typed as BVDV-1f. Conclusion. Our results indicated that the BVDV infection is widespread in cattle herds in the eastern Ukraine, that requires further research and development of new approaches to improve the current situation.

Serum folate, cobalamin, homocysteine and methylmalonic acid concentrations in pigs with acute, chronic or subclinical Lawsonia intracellularis infection.

Lawsonia intracellularis is the causative agent of porcine proliferative enteropathy. The clinical presentation can be acute (i.e. proliferative hemorrhagic enteropathy, PHE), chronic (i.e. porcine intestinal adenomatosis, PIA) or subclinical. In humans with chronic enteropathies, low serum folate (vitamin B(9)) and cobalamin (vitamin B(12)) concentrations have been associated with increased serum concentrations of homocysteine and methylmalonic acid (MMA), which reflect the availability of both vitamins at the cellular level. The aim of this study was to evaluate serum folate, cobalamin, homocysteine and MMA concentrations in serum samples from pigs with PHE, PIA or subclinical L. intracellularis infection, and in negative controls. Serum folate, cobalamin, homocysteine and MMA concentrations differed significantly among pigs in the PHE, PIA, subclinical and negative control groups. Serum folate concentrations in the PHE and PIA groups were lower than in the subclinical and negative control groups, while serum cobalamin concentrations were lower in the PIA group than in other groups. Serum concentrations of homocysteine were higher in the PHE, PIA and subclinical groups than in the negative control group. Serum concentrations of MMA were higher in the subclinical and PIA groups than in the control group. These data suggest that pigs infected with L. intracellularis have altered serum cobalamin, folate, homocysteine and MMA concentrations.

Deletion of Fibrinogen-like Protein 2 (FGL-2), a Novel CD4+ CD25+ Treg Effector Molecule, Leads to Improved Control of Echinococcus multilocularis Infection in Mice.

BACKGROUND The growth potential of the tumor-like Echinococcus multilocularis metacestode (causing alveolar echinococcosis, AE) is directly linked to the nature/function of the periparasitic host immune-mediated processes. We previously showed that Fibrinogen-like-protein 2 (FGL2), a novel CD4+CD25+ Treg effector molecule, was over-expressed in the liver of mice experimentally infected with E. multilocularis. However, little is known about its contribution to the control of this chronic helminth infection. METHODS/FINDINGS Key parameters for infection outcome in E. multilocularis-infected fgl2-/- (AE-fgl2-/-) and wild type (AE-WT) mice at 1 and 4 month(s) post-infection were (i) parasite load (i. e. wet weight of parasitic metacestode tissue), and (ii) parasite cell proliferation as assessed by determining E. multilocularis 14-3-3 gene expression levels. Serum FGL2 levels were measured by ELISA. Spleen cells cultured with ConA for 48h or with E. multilocularis Vesicle Fluid (VF) for 96h were analyzed ex-vivo and in-vitro. In addition, spleen cells from non-infected WT mice were cultured with rFGL2/anti-FGL2 or rIL-17A/anti-IL-17A for further functional studies. For Treg-immune-suppression-assays, purified CD4+CD25+ Treg suspensions were incubated with CD4+ effector T cells in the presence of ConA and irradiated spleen cells as APCs. Flow cytometry and qRT-PCR were used to assess Treg, Th17-, Th1-, Th2-type immune responses and maturation of dendritic cells. We showed that AE-fgl2-/- mice exhibited (as compared to AE-WT-animals) (a) a significantly lower parasite load with reduced proliferation activity, (b) an increased T cell proliferative response to ConA, (c) reduced Treg numbers and function, and (d) a persistent capacity of Th1 polarization and DC maturation. CONCLUSIONS FGL2 appears as one of the key players in immune regulatory processes favoring metacestode survival by promoting Treg cell activity and IL-17A production that contributes to FGL2-regulation. Prospectively, targeting FGL2 could be an option to develop an immunotherapy against AE and other chronic parasitic diseases.

Echinococcus granulosus infection dynamics in livestock of Greece

An epidemiological and molecular survey on the occurrence of Echinococcus hydatid cysts in livestock was conducted in Greece. In total 898 sheep, 483 goats, 38 buffaloes, 273 wild boars and 15 deer were examined and 30.2% (6.45% cyst fertility), 7.86% (3.2% cyst fertility), 42% (7.9% cyst fertility), 1.1% (0% cyst fertility), 0% of them were found infected, respectively. Infection rate in different geographical regions varied between 26.1 and 53.8% (cyst fertility 2.04 and 34.6%) in sheep, 7.33 and 13.3% (cyst fertility 0 and 3.2%) in goats. Genotyping, based on cox1 and nad1 analyses, demonstrated the predominance of E. granulosus s.s. (G1 genotype). The presence of one single genotype-complex within a relatively large spectrum of intermediate host species in Greece indicates the presence of a dominant transmission dog-sheep cycle involving additional host species which may act as disease reservoir for human infections.

Comparison of the diagnostic significance of clinical, radiographic and ultrasonographic results after an experimental aerosol infection of pigs with Actinobacillus pleuropneumoniae

Scoring schemes for clinical, ultrasonographic and radiographic findings in pigs were developed based upon a standardized animal model for Actinobacillus pleuropneumoniae infection.The results of these methods were compared to each other as well as with the corresponding pathomorphological findings during necropsy. Altogether 69 pigs of different breeding lines (Hampshire, Pietrain and German Landrace were examined. Positive correlations were found between the results of all three methods as well as with the necropsy scores (p <0.0001). Different pathomorphological findings were detected either by radiographic or by ultrasonographic examination dependent upon the type of lung tissue alterations: Alterations of the pleura as well as sequestration of lung tissue on the lung surface could be clearly identified during the ultrasonographic examination while deep tissue alterations with no contact to the lung surface could be detected reliably by radiographic examination. Both methods complement each other, and the application of a combined ultrasonographic and radiographic examination of the thorax allows a comprehensive inspection of the lung condition. Particularly during the acute phase of the disease the extent of lung tissue damage can be estimated more precisely than by clinical examination alone.

HIV and human herpesvirus 8 co-infection across the globe: Systematic review and meta-analysis.

HIV-infection is an important risk factor for developing Kaposi sarcoma (KS), but it is unclear whether HIV-positive persons are also at increased risk of co-infection with human herpesvirus 8 (HHV-8), the infectious cause of KS. We systematically searched literature up to December 2012 and included studies reporting HHV-8 seroprevalence for HIV-positive and HIV-negative persons. We used random-effects meta-analysis to combine odds ratios (ORs) of the association between HIV and HHV-8 seropositivity and conducted random-effects meta-regression to identify sources of heterogeneity. We included 93 studies with 58,357 participants from 32 countries in sub-Saharan Africa, North and South America, Europe, Asia, and Australia. Overall, HIV-positive persons were more likely to be HHV-8 seropositive than HIV-negative persons (OR 1.99, 95% confidence interval [CI] 1.70-2.34) with considerable heterogeneity among studies (I(2) 84%). The association was strongest in men who have sex with men (MSM, OR 3.95, 95% CI 2.92-5.35), patients with hemophilia (OR 3.11, 95% CI 1.19-8.11), and children (OR 2.45, 95% CI 1.58-3.81), but weaker in heterosexuals who engage in low-risk (OR 1.42, 95% CI 1.16-1.74) or high-risk sexual behavior (OR 1.66, 95% CI 1.27-2.17), persons who inject drugs (OR 1.66, 95% CI 1.28-2.14), and pregnant women (OR 1.68, 95% CI 1.15-2.47), p value for interaction <0.001. In conclusion, HIV-infection was associated with an increased HHV-8 seroprevalence in all population groups examined. A better understanding of HHV-8 transmission in different age and behavioral groups is needed to develop strategies to prevent HHV-8 transmission.

HIV testing and burden of HIV infection in black cancer patients in Johannesburg, South Africa: a cross-sectional study.

BACKGROUND HIV infection is a known risk factor for cancer but little is known about HIV testing patterns and the burden of HIV infection in cancer patients. We did a cross-sectional analysis to identify predictors of prior HIV testing and to quantify the burden of HIV in black cancer patients in Johannesburg, South Africa. METHODS The Johannesburg Cancer Case-control Study (JCCCS) recruits newly-diagnosed black cancer patients attending public referral hospitals for oncology and radiation therapy in Johannesburg . All adult cancer patients enrolled into the JCCCS from November 2004 to December 2009 and interviewed on previous HIV testing were included in the analysis. Patients were independently tested for HIV-1 using a single ELISA test . The prevalence of prior HIV testing, of HIV infection and of undiagnosed HIV infection was calculated. Multivariate logistic regression models were fitted to identify factors associated with prior HIV testing. RESULTS A total of 5436 cancer patients were tested for HIV of whom 1833[33.7% (95% CI=32.5-35.0)] were HIV-positive. Three-quarters of patients (4092 patients) had ever been tested for HIV. The total prevalence of undiagnosed HIV infection was 11.5% (10.7-12.4) with 34% (32.0-36.3) of the 1833 patients who tested HIV-positive unaware of their infection. Men >49 years [OR 0.49(0.39-0.63)] and those residing in rural areas [OR 0.61(0.39-0.97)] were less likely to have been previously tested for HIV. Men with at least a secondary education [OR 1.79(1.11-2.90)] and those interviewed in recent years [OR 4.13(2.62 - 6.52)] were likely to have prior testing. Women >49 years [OR 0.33(0.27-0.41)] were less likely to have been previously tested for HIV. In women, having children <5 years [OR 2.59(2.04-3.29)], hormonal contraceptive use [OR 1.33(1.09-1.62)], having at least a secondary education [OR:2.08(1.45-2.97)] and recent year of interview [OR 6.04(4.45-8.2)] were independently associated with previous HIV testing. CONCLUSIONS In a study of newly diagnosed black cancer patients in Johannesburg, over a third of HIV-positive patients were unaware of their HIV status. In South Africa black cancer patients should be targeted for opt-out HIV testing.

Mutation of the ER retention receptor KDELR1 leads to cell-intrinsic lymphopenia and a failure to control chronic viral infection

Endoplasmic reticulum (ER)-resident proteins are continually retrieved from the Golgi and returned to the ER by Lys-Asp-Glu-Leu (KDEL) receptors, which bind to an eponymous tetrapeptide motif at their substrate's C terminus. Mice and humans possess three paralogous KDEL receptors, but little is known about their functional redundancy, or if their mutation can be physiologically tolerated. Here, we present a recessive mouse missense allele of the prototypical mammalian KDEL receptor, KDEL ER protein retention receptor 1 (KDELR1). Kdelr1 homozygous mutants were mildly lymphopenic, as were mice with a CRISPR/Cas9-engineered frameshift allele. Lymphopenia was cell intrinsic and, in the case of T cells, was associated with reduced expression of the T-cell receptor (TCR) and increased expression of CD44, and could be partially corrected by an MHC class I-restricted TCR transgene. Antiviral immunity was also compromised, with Kdelr1 mutant mice unable to clear an otherwise self-limiting viral infection. These data reveal a nonredundant cellular function for KDELR1, upon which lymphocytes distinctly depend.