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.

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.

A cross sectional examination of risky sexual behaviors among a population of drug users

This study is a secondary data analysis that assesses the relationship between risky sexual behaviors and sexually transmitted infections (STIs) among drug users. This study analyzes data collected from drug users in the Houston Metropolitan area during 2004 and through August 2005, by researchers with the DASH (Drugs, AIDS, STDs and Hepatitis) project at The University of Texas at Houston School of Public Health. Specifically, the sexually transmitted infections that will be of interest in this proposed study are Human Immunodeficiency Virus (HIV) and Hepatitis B Virus (HBV). Risky sexual behaviors that will be examined include lack of condom use, sexual orientation, trading sex for drugs, trading sex for money, and number of male and female sexual partners in the last 4 weeks. ^ Unadjusted, gender, sexual orientation, number of recent male and female sex partners, and a history of injection drug use were all found to be significant independent variables that increased the odds of STI status. When included in an overall model, these variables significantly increased the odds of STI status, including HBV infection, HIV infection, and HBV/HIV co-infection. History of injection drug use was significant for both HBV and HBV/HIV co-infection, whereas a gay sexual orientation was significant for both HIV and HBV/HIV co-infection. Additionally, having excessive female sex partners was significant for HIV infection. This significant association increases the need for implementation of stronger intervention programs tailored to suit this population's needs such as a combination of drug and sexually transmitted disease (STD) treatment. ^ The importance of these findings is that they establish the strength of associations between the previously mentioned risky sexual behaviors and STI status among drug users. This is crucial for assessing future risk of infection as well as for serving as a necessary component in intervention and treatment programs both for drug use and STIs. ^

Trends in incidences and risk factors for hepatocellular carcinoma and other liver events in HIV and hepatitis C virus co-infected individuals from 2001 to 2014: a multi-cohort study.

BACKGROUND  While liver-related deaths in HIV and hepatitis C virus (HCV) co-infected individuals have declined over the last decade, hepatocellular carcinoma (HCC) may have increased. We described the epidemiology of HCC and other liver events in a multi-cohort collaboration of HIV/HCV co-infected individuals. METHODS  We studied all HCV antibody-positive adults with HIV in the EuroSIDA Study, the Southern Alberta Clinic Cohort, the Canadian Co-infection Cohort, and the Swiss HIV Cohort Study from 2001 to 2014. We calculated the incidence of HCC and other liver events (defined as liver-related deaths or decompensations, excluding HCC) and used Poisson regression to estimate incidence rate ratios. RESULTS  Our study comprised 7,229 HIV/HCV co-infected individuals (68% male, 90% white). During follow-up, 72 cases of HCC and 375 other liver events occurred, yielding incidence rates of 1.6 (95% confidence interval (CI): 1.3, 2.0) and 8.6 (95% CI: 7.8, 9.5) cases per 1,000 person-years of follow-up, respectively. The rate of HCC increased 11% per calendar year (95% CI: 4%, 19%) and decreased 4% for other liver events (95% CI: 2%, 7%), but only the latter remained statistically significant after adjustment for potential confounders. High age, cirrhosis, and low current CD4 cell count were associated with a higher incidence of both HCC and other liver events. CONCLUSIONS  In HIV/HCV co-infected individuals, the crude incidence of HCC increased from 2001 to 2014, while other liver events declined. Individuals with cirrhosis or low current CD4 cell count are at highest risk of developing HCC or other liver events.

Co mo vivir una vida positiva.

In Spanish.

Impact of Cryptosporidium spp. interaction with co-occurring microorganisms on moderate-to-severe diarrhea in the developing world

Diarrheal illness is responsible for over a quarter of all deaths in children under 5 years of age in sub-Saharan Africa and South Asia. Recent findings have identified the parasite Cryptosporidium as a contributor to enteric disease. We examined 9,348 cases and 13,128 controls from the Global Enteric Multicenter Study to assess whether Cryptosporidium interacted with co-occurring pathogens based on adjusted odds of moderate-to-severe diarrhea (MSD). Cryptosporidium was found to interact negatively with Shigella spp., with multiplicative interaction score of 0.16 (95% CI: 0.07 to 0.37, p-value=0.000), and an additive interaction score of -9.81 (95% CI: -13.61 to -6.01, p-value=0.000). Cryptosporidium also interacted negatively with Aeromonas spp., Adenovirus, Norovirus, and Astrovirus with marginal significance. Odds of MSD for Cryptosporidium co-infection with Shigella spp., Aeromonas spp., Adenovirus, Norovirus, or Astrovirus are lower than odds of MSD with either organism alone. This may reduce the efficacy of intervention strategies targeted at Cryptosporidium.

Thyroid function in multidrug-resistant tuberculosis patients with or without human immunodeficiency virus (HIV) infection before commencement of MDR-TB drug regimen.

Background: Mycobacterium tuberculosis and human immunodeficiency virus (HIV) are known to cause abnormal thyroid function. There is little information on whether HIV infection aggravates alteration of thyroid function in patients with MDRTB. Objectives: This study was carried out to determine if HIV co-infection alters serum levels of thyroid hormones (T3, T4) and thyroid stimulating hormone (TSH) in patients with MDR-TB patients and to find out the frequency of subclinical thyroid dysfunction before the commencement of MDR-TB therapy. Methods: This observational and cross-sectional study involved all the newly admitted patients in MDR-TB Referral Centre, University College Hospital, Ibadan, Nigeria between July 2010 and December 2014. Serum levels of thyroid stimulating hormone (TSH), free thyroxine (fT4) and free triiodothyronine (fT3) were determined using ELISA. Results: Enrolled were 115 patients with MDR-TB, out of which 22 (19.13%) had MDR-TB/HIV co-infection. Sick euthyroid syndrome (SES), subclinical hypothyroidism and subclinical hyperthyroidism were observed in 5 (4.35%), 9 (7.83%) and 2 (1.74%) patients respectively. The median level of TSH was insignificantly higher while the median levels of T3 and T4 were insignificantly lower in patients with MDR-TB/HIV co-infection compared with patients with MDRT-TB only. Conclusion: It could be concluded from this study that patients with MDR-TB/HIV co-infection have a similar thyroid function as patients having MDR-TB without HIV infection before commencement of MDR-TB drug regimen. Also, there is a possibility of subclinical thyroid dysfunction in patients with MDR-TB/HIV co-infection even, before the commencement of MDR-TB therapy.

Transcriptional analysis of PRRSV-infected porcine dendritic cell response to Streptococcus suis infection reveals up-regulation of inflammatory-related genes expression

The porcine reproductive and respiratory syndrome virus (PRRSV) is one of the most important swine pathogens and often serves as an entry door for other viral or bacterial pathogens, of which Streptococcus suis is one of the most common. Pre-infection with PRRSV leads to exacerbated disease caused by S. suis infection. Very few studies have assessed the immunological mechanisms underlying this higher susceptibility. Since antigen presenting cells play a major role in the initiation of the immune response, the in vitro transcriptional response of bone marrow-derived dendritic cells (BMDCs) and monocytes in the context of PRRSV and S. suis co-infection was investigated. BMDCs were found to be more permissive than monocytes to PRRSV infection; S. suis phagocytosis by PRRSV-infected BMDCs was found to be impaired, whereas no effect was found on bacterial intracellular survival. Transcription profile analysis, with a major focus on inflammatory genes, following S. suis infection, with and without pre-infection with PRRSV, was then performed. While PRRSV pre-infection had little effect on monocytes response to S. suis infection, a significant expression of several pro-inflammatory molecules was observed in BMDCs pre-infected with PRRSV after a subsequent infection with S. suis. While an additive effect could be observed for CCL4, CCL14, CCL20, and IL-15, a distinct synergistic up-regulatory effect was observed for IL-6, CCL5 and TNF-α after co-infection. This increased pro-inflammatory response by DCs could participate in the exacerbation of the disease observed during PRRSV and S. suis co-infection.

The influence of HIV, HCV and inhibitors on the quality of life and behavior of the disease in patients with haemophilia: An observational study

Inhibitors are the main complication in the treatment of haemophilia. A high percentage of adult patients were infected in past decades by HIV and HCV through factor concentrates. This study compared the quality of life of patients with hemophilia (QoL) and illness behavior in adult patients with haemophilia according to the development of inhibitors and HIV or HCV co-infection. This is an observational clinical study. 69 adult patients with haemophilia participated. We used A36 Hemophilia-QoL and IBQ questionnaires to measure the QoL and illness behavior, respectively. The dependent variables were type and severity of haemophilia, type of treatment, development of inhibitors, HIV and HCV infection, or both. We observed significant differences in the perception of QoL and illness behavior in patients according to the development of inhibitor and coinfection with HIV-HCV. We obtained four groups: the first and second group, which comprise 67% of the sample, exhibit behavior patterns indicating good adaptation to the disease and good QoL. The other two groups, which comprise 33% of the sample show behavior that is not well adapted to the disease, and poor quality of life. The development of inhibitors itself does not influence the quality of life and illness behavior in patients with haemophilia. Patients infected with HIV or HCV do not have a worse illness behavior compared to those uninfected. The development of inhibitors and HIV-HCV co-infection has a negative impact on quality of life and illness behavior in patients with haemophilia.

Transcriptional analysis of PRRSV-infected porcine dendritic cell response to Streptococcus suis infection reveals up-regulation of inflammatory-related genes expression

The porcine reproductive and respiratory syndrome virus (PRRSV) is one of the most important swine pathogens and often serves as an entry door for other viral or bacterial pathogens, of which Streptococcus suis is one of the most common. Pre-infection with PRRSV leads to exacerbated disease caused by S. suis infection. Very few studies have assessed the immunological mechanisms underlying this higher susceptibility. Since antigen presenting cells play a major role in the initiation of the immune response, the in vitro transcriptional response of bone marrow-derived dendritic cells (BMDCs) and monocytes in the context of PRRSV and S. suis co-infection was investigated. BMDCs were found to be more permissive than monocytes to PRRSV infection; S. suis phagocytosis by PRRSV-infected BMDCs was found to be impaired, whereas no effect was found on bacterial intracellular survival. Transcription profile analysis, with a major focus on inflammatory genes, following S. suis infection, with and without pre-infection with PRRSV, was then performed. While PRRSV pre-infection had little effect on monocytes response to S. suis infection, a significant expression of several pro-inflammatory molecules was observed in BMDCs pre-infected with PRRSV after a subsequent infection with S. suis. While an additive effect could be observed for CCL4, CCL14, CCL20, and IL-15, a distinct synergistic up-regulatory effect was observed for IL-6, CCL5 and TNF-α after co-infection. This increased pro-inflammatory response by DCs could participate in the exacerbation of the disease observed during PRRSV and S. suis co-infection.

Evaluación del desempeño de pruebas diagnósticas de tuberculosis en pacientes VIH positivo en dos hospitales públicos de Bogotá

La tuberculosis TB es una de las principales causas de muerte en el mundo en individuos con infección por VIH. En Colombia esta coinfección soporta una carga importante en la población general convirtiéndose en un problema de salud pública. En estos pacientes las pruebas diagnósticas tienen sensibilidad inferior y la enfermedad evoluciona con mayor frecuencia hacia formas diseminadas y rápidamente progresivas y su diagnóstico oportuno representa un reto en Salud. El objetivo de este proyecto es evaluar el desempeño de las pruebas diagnósticas convencionales y moleculares, para la detección de TB latente y activa pacientes con VIH, en dos hospitales públicos de Bogotá. Para TB latente se evaluó la concordancia entre las pruebas QuantiFERON-TB (QTF) y Tuberculina (PPD), sugiriendo superioridad del QTF sobre la PPD. Se evaluaron tres pruebas diagnósticas por su sensibilidad y especificidad, baciloscopia (BK), GenoType®MTBDR plus (Genotype) y PCR IS6110 teniendo como estándar de oro el cultivo. Los resultados de sensibilidad (S) y especificidad (E) de cada prueba con una prevalencia del 19,4 % de TB pulmonar y extrapulmonar en los pacientes que participaron del estudio fue: BK S: 64% E: 99,1%; Genotype S: 77,8% E: 94,5%; PCRIS6110 S: 73% E: 95,5%, de la misma forma se determinaron los valores predictivos positivos y negativos (VPP y VPN) BK: 88,9% y 94,8%, Genotype S: 77,8% E: 94,5%; PCRIS6110 S: 90% y 95,7%. Se concluyó bajo análisis de curva ROC que las pruebas muestran un rendimiento diagnóstico similar por separado en el diagnóstico de TB en pacientes con VIH, aumentando su rendimiento diagnostico cuando se combinan

Epidemiological studies on toxoplasma gondii infection in a one health perspective

The objective of the present Ph.D. thesis was to investigate with a One Health approach the epidemiological patterns of T. gondii infection in Italy, to better understand the transmission dynamics of the parasite, following different research lines. The results of a retrospective analysis in animals and human showed the widespread distribution of T. gondii in the study area, with specific antibodies found in various animal species and human populations, indicating its constant presence across diverse environments. The environment plays a significant role in T. gondii's epidemiology. Migratory aquatic birds, rodents, wolves, and wild boars were investigated as sentinels of their spread, highlighting the potential transmission across geographic areas and infection risks for wildlife in natural settings. The study also provided insights into seroprevalence in wolves. Dogs, subjected to serological investigations exhibited risk factors for T. gondii infection, such as cohabitation with cats, coprophagy behaviours, and continuous outdoor. Correlation between serological evidence of exposure to T. gondii and pathological anxiety in large-size dogs was observed, and the consumption of raw meat was associated with a higher risk of infection in these animals. Results of the investigations conducted in this thesis, demonstrate the dynamic nature of T. gondii infection in cattle, characterized by new infections and declining antibody levels over the production cycle. The study also describes a co-infection between T. gondii and Sarcocystis hominis in bovine eosinophilic myositis. In the final part of the Thesis, a comprehensive genotyping of T. gondii in Italy reveals the predominance of Type II strains, particularly in cases of ovine abortion and fatal toxoplasmosis among captive Lemur catta. This approach enhances our understanding of the parasite's genetic diversity and transmission patterns, vital for effective management of its impact on human and animal health in Italy.

Molecular detection of Hepatozoon canis and Babesia canis vogeli in domestic dogs from Cuiabá, Brazil

The objective of this study was to report for the first time infection by Hepatozoon spp. and Babesia spp. in 10 dogs from the city of Cuiabá, State of Mato Grosso, central-western Brazil. A pair of primers that amplifies a 574 bp fragment of the 18S rRNA of Hepatozoon spp., and a pair of primers that amplifies a 551 bp fragment of the gene 18S rRNA for Babesia spp. were used. Six dogs were positive for Babesia spp., and 9 were positive for Hepatozoon spp. Co-infection of Babesia spp. and Hepatozoon spp. was seen in 5 dogs. Sequenced samples revealed 100% identity with B. canis vogeli, and H. canis. This is the first molecular detection of H. canis in domestic dogs from Cuiabá. Additionally, it is described for the first time the presence of B. canis vogeli circulating among dogs in Cuiabá.

Real-Time PCR in HIV/Trypanosoma cruzi Coinfection with and without Chagas Disease Reactivation: Association with HIV Viral Load and CD4(+) Level

Background: Reactivation of chronic Chagas disease, which occurs in approximately 20% of patients coinfected with HIV/Trypanosoma cruzi (T. cruzi), is commonly characterized by severe meningoencephalitis and myocarditis. The use of quantitative molecular tests to monitor Chagas disease reactivation was analyzed. Methodology: Polymerase chain reaction (PCR) of kDNA sequences, competitive (C-) PCR and real-time quantitative (q) PCR were compared with blood cultures and xenodiagnosis in samples from 91 patients (57 patients with chronic Chagas disease and 34 with HIV/T. cruzi coinfection), of whom 5 had reactivation of Chagas disease and 29 did not. Principal Findings: qRT-PCR showed significant differences between groups; the highest parasitemia was observed in patients infected with HIV/T. cruzi with Chagas disease reactivation (median 1428.90 T. cruzi/mL), followed by patients with HIV/T. cruzi infection without reactivation (median 1.57 T. cruzi/mL) and patients with Chagas disease without HIV (median 0.00 T. cruzi/mL). Spearman's correlation coefficient showed that xenodiagnosis was correlated with blood culture, C-PCR and qRT-PCR. A stronger Spearman correlation index was found between C-PCR and qRT-PCR, the number of parasites and the HIV viral load, expressed as the number of CD4(+) cells or the CD4(+)/CD8(+) ratio. Conclusions: qRT-PCR distinguished the groups of HIV/T. cruzi coinfected patients with and without reactivation. Therefore, this new method of qRT-PCR is proposed as a tool for prospective studies to analyze the importance of parasitemia (persistent and/or increased) as a criterion for recommending pre-emptive therapy in patients with chronic Chagas disease with HIV infection or immunosuppression. As seen in this study, an increase in HIV viral load and decreases in the number of CD4(+) cells/mm(3) and the CD4(+)/CD8(+) ratio were identified as cofactors for increased parasitemia that can be used to target the introduction of early, pre-emptive therapy.

Cost-effectiveness analysis of PCR for the rapid diagnosis of pulmonary tuberculosis

Background: Tuberculosis is one of the most prominent health problems in the world, causing 1.75 million deaths each year. Rapid clinical diagnosis is important in patients who have comorbidities such as Human Immunodeficiency Virus (HIV) infection. Direct microscopy has low sensitivity and culture takes 3 to 6 weeks [1-3]. Therefore, new tools for TB diagnosis are necessary, especially in health settings with a high prevalence of HIV/TB co-infection. Methods: In a public reference TB/HIV hospital in Brazil, we compared the cost-effectiveness of diagnostic strategies for diagnosis of pulmonary TB: Acid fast bacilli smear microscopy by Ziehl-Neelsen staining (AFB smear) plus culture and AFB smear plus colorimetric test (PCR dot-blot). From May 2003 to May 2004, sputum was collected consecutively from PTB suspects attending the Parthenon Reference Hospital. Sputum samples were examined by AFB smear, culture, and PCR dot-blot. The gold standard was a positive culture combined with the definition of clinical PTB. Cost analysis included health services and patient costs. Results: The AFB smear plus PCR dot-blot require the lowest laboratory investment for equipment (US$ 20,000). The total screening costs are 3.8 times for AFB smear plus culture versus for AFB smear plus PCR dot blot costs (US$ 5,635,760 versus US$ 1,498, 660). Costs per correctly diagnosed case were US$ 50,773 and US$ 13,749 for AFB smear plus culture and AFB smear plus PCR dot-blot, respectively. AFB smear plus PCR dot-blot was more cost-effective than AFB smear plus culture, when the cost of treating all correctly diagnosed cases was considered. The cost of returning patients, which are not treated due to a negative result, to the health service, was higher in AFB smear plus culture than for AFB smear plus PCR dot-blot, US$ 374,778,045 and US$ 110,849,055, respectively. Conclusion: AFB smear associated with PCR dot-blot associated has the potential to be a cost-effective tool in the fight against PTB for patients attended in the TB/HIV reference hospital.