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Rabiu OR, Dada-Adegbola H, Falade CO, Arinola OG, Odaibo AB, Ademowo OG. Serum cytokine profile of pregnant women with malaria, intestinal helminths and HIV infections in Ibadan, Nigeria. Parasitol Res 2022; 121:1983-1992. [PMID: 35522326 DOI: 10.1007/s00436-022-07531-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2021] [Accepted: 04/25/2022] [Indexed: 11/25/2022]
Abstract
Malaria, helminthiasis and HIV are widespread in developing countries taking a heavy toll on pregnant women. Due to similar environmental and human factors of transmission, they co-exist. The epidemiology and pathology of these diseases have been extensively studied but data on serum cytokine profile changes which is crucial in pregnancy is limited. The aim of this study was to evaluate the co-infections and their impact on peripheral blood cytokines. Blood and stool samples were collected from recruited 18-45-year-old pregnant women in different trimesters who were apparently healthy with no obvious complications in pregnancy. Pretested questionnaires were administered for personal and socio-demographic details. Malaria parasitemia in Giemsa-stained thick blood films was examined microscopically. Stool samples were screened for helminths using Kato-Katz method. Cytokine levels of TNF-α, IFN-γ, IL-1α, IL-2, IL-4, IL-6, IL-10, IL-12p70, IL-13 and IL-17 in 121 serum samples were determined using ELISA. Data were analysed using descriptive statistics and Mann-Whitney U test at α0.05. Relative to the single infections, there were significant reductions in IFN-γ and IL-13 in second and third trimesters respectively in those with Plasmodium and helminth co-infection. IFN-γ and IL-17 were elevated while IL-1α and IL-12p70 were reduced in co-infection of helminths and HIV. Co-infection of Plasmodium and HIV in second and third trimesters showed significant elevations in IL-1α, IL-10 and IL-17 while TNF-α, IL-4 and IL-12p70 were significantly reduced. HIV in pregnancy and its co-infection with Plasmodium resulted in significant distortions in the cytokine profile. However, helminth and its co-infection with Plasmodium or HIV produced less changes in the cytokine profile.
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Affiliation(s)
- Olawunmi R Rabiu
- Department of Zoology, University of Ibadan, Ibadan, Nigeria
- Institute for Advanced Medical Research and Training, College of Medicine, University of Ibadan, Ibadan, Nigeria
- Department of Biological Sciences, Mountain Top University, Prayer City, Ogun State, Nigeria
| | - Hannah Dada-Adegbola
- Department of Medical Microbiology and Parasitology, College of Medicine, University of Ibadan, Ibadan, Nigeria
| | - Catherine O Falade
- Institute for Advanced Medical Research and Training, College of Medicine, University of Ibadan, Ibadan, Nigeria
- Department of Pharmacology and Therapeutics, University of Ibadan, Ibadan, Nigeria
| | - Olatunbosun G Arinola
- Department of Immunology, College of Medicine, University of Ibadan, Ibadan, Nigeria
| | | | - Olusegun G Ademowo
- Institute for Advanced Medical Research and Training, College of Medicine, University of Ibadan, Ibadan, Nigeria.
- Department of Pharmacology and Therapeutics, University of Ibadan, Ibadan, Nigeria.
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Clark E, Serpa JA. Tropical Diseases in HIV. CURRENT TREATMENT OPTIONS IN INFECTIOUS DISEASES 2019. [DOI: 10.1007/s40506-019-00194-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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3
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Mabbott NA. The Influence of Parasite Infections on Host Immunity to Co-infection With Other Pathogens. Front Immunol 2018; 9:2579. [PMID: 30467504 PMCID: PMC6237250 DOI: 10.3389/fimmu.2018.02579] [Citation(s) in RCA: 71] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2018] [Accepted: 10/19/2018] [Indexed: 12/13/2022] Open
Abstract
Parasites have evolved a wide range of mechanisms that they use to evade or manipulate the host's immune response and establish infection. The majority of the in vivo studies that have investigated these host-parasite interactions have been undertaken in experimental animals, especially rodents, which were housed and maintained to a high microbiological status. However, in the field situation it is increasingly apparent that pathogen co-infections within the same host are a common occurrence. For example, chronic infection with pathogens including malarial parasites, soil-transmitted helminths, Mycobacterium tuberculosis and viruses such as HIV may affect a third of the human population of some developing countries. Increasing evidence shows that co-infection with these pathogens may alter susceptibility to other important pathogens, and/or influence vaccine efficacy through their effects on host immune responsiveness. Co-infection with certain pathogens may also hinder accurate disease diagnosis. This review summarizes our current understanding of how the host's immune response to infection with different types of parasites can influence susceptibility to infection with other pathogenic microorganisms. A greater understanding of how infectious disease susceptibility and pathogenesis can be influenced by parasite co-infections will enhance disease diagnosis and the design of novel vaccines or therapeutics to more effectively control the spread of infectious diseases.
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Affiliation(s)
- Neil A Mabbott
- The Roslin Institute & Royal (Dick) School of Veterinary Studies, University of Edinburgh, Edinburgh, United Kingdom
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Colombe S, Machemba R, Mtenga B, Lutonja P, Kalluvya SE, de Dood CJ, Hoekstra PT, van Dam GJ, Corstjens PLAM, Urassa M, Changalucha JM, Todd J, Downs JA. Impact of schistosome infection on long-term HIV/AIDS outcomes. PLoS Negl Trop Dis 2018; 12:e0006613. [PMID: 29965987 PMCID: PMC6044552 DOI: 10.1371/journal.pntd.0006613] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2018] [Revised: 07/13/2018] [Accepted: 06/15/2018] [Indexed: 01/31/2023] Open
Abstract
Background Africa bears the burden of approximately 70% of global HIV infections and 90% of global schistosome infections. We sought to investigate the impact of schistosome infection at the time of HIV-1 seroconversion on the speed of HIV-1 disease progression, as measured by the outcome CD4+ T-cell (CD4) counts <350 cells/μL and/or death. We hypothesized that people who had been infected with Schistosoma spp. at the time they acquired HIV-1 infection would have impaired antiviral immune response, thus leading them to progress twice as fast to a CD4 count less than 350 cells/μL or death than would people who had been free of schistosomes at time of HIV-1 seroconversion. Methods and principal findings We conducted a longitudinal study in Tanzania from 2006 to 2017 using stored blood spot samples, demographic surveillance and sero-survey data from the community, and a review of clinical charts. A competing risk analysis was performed to look at the difference in time to reaching CD4 counts < 350 cells/μL and/or death in HIV-1-infected people who were infected versus not infected with Schistosoma spp. at time of HIV-1 seroconversion. We found an 82% reduction in risk of reaching the outcome in seroconverters who had been infected with Schistosoma (subHazard Ratio = 0.18[0.068,0.50], p = 0.001) after adjusting for age, occupation, clinic attendance and time-dependent covariates. Conclusions Our study demonstrates that people with schistosome infection at the time of HIV-seroconversion develop adverse HIV outcomes more slowly than those without. The findings are contrary to our original hypothesis. Our current longitudinal findings suggest complex interactions between HIV-1 and schistosome co-infections that may be modulated over time. We urge new immunological studies to investigate the long-term impact of schistosome infection on HIV-1 viral load and CD4 counts as well as related immunologic pathways. Several studies had shown that people infected with schistosome parasites were at risk of getting HIV and that they may have higher HIV viral concentrations in their blood as well. The authors explored the impact of the parasite on HIV disease after infection, expecting that people co-infected with the parasite at time of HIV-infection would develop worse HIV outcomes than people who did not have the parasite. HIV seroconverters were identified among a large cohort tested regularly for HIV in northwest Tanzania and were followed-up in clinics to determine their CD4 + T-cells counts and mortality. The seroconverters’ stored blood samples were tested for infection with the parasite and outcomes were compared between seroconverters who were and were not infected with the parasites at the time that they became HIV-infected. The authors surprisingly found that people with the parasite experienced fewer negative outcomes of HIV than people who did not have the parasite. To the investigators’ knowledge, this is the first longitudinal study to find this result. Long-term immunological changes may explain this protective effect and more studies are recommended to explore this research question.
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Affiliation(s)
- Soledad Colombe
- Center for Global Health, Weill Cornell Medicine, New York, New York, United States of America
- * E-mail:
| | | | | | - Peter Lutonja
- National Institute of Medical Research, Mwanza, Tanzania
| | | | - Claudia J. de Dood
- Department of Molecular Cell Biology, Leiden University Medical Centre, Leiden, Netherlands
| | - Pytsje T. Hoekstra
- Department of Parasitology, Leiden University Medical Centre, Leiden, Netherlands
| | - Govert J. van Dam
- Department of Parasitology, Leiden University Medical Centre, Leiden, Netherlands
| | | | - Mark Urassa
- National Institute of Medical Research, Mwanza, Tanzania
| | | | - Jim Todd
- Department of Applied Biostatistics, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Jennifer A. Downs
- Center for Global Health, Weill Cornell Medicine, New York, New York, United States of America
- Department of Medicine, Bugando Medical Centre, Mwanza, Tanzania
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5
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Evans EE, Siedner MJ. Tropical Parasitic Infections in Individuals Infected with HIV. CURRENT TROPICAL MEDICINE REPORTS 2017; 4:268-280. [PMID: 33842194 PMCID: PMC8034600 DOI: 10.1007/s40475-017-0130-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
PURPOSE OF REVIEW Neglected tropical diseases share both geographic and socio-behavioral epidemiological risk factors with HIV infection. In this literature review, we describe interactions between parasitic diseases and HIV infection, with a focus on the impact of parasitic infections on HIV infection risk and disease progression, and the impact of HIV infection on clinical characteristics of tropical parasitic infections. We limit our review to tropical parasitic infections of the greatest public health burden, and exclude discussion of classic HIV-associated opportunistic infections that have been well reviewed elsewhere. RECENT FINDINGS Tropical parasitic infections, HIV-infection, and treatment with antiretroviral therapy alter host immunity, which can impact susceptibility, transmissibility, diagnosis, and severity of both HIV and parasitic infections. These relationships have a broad range of consequences, from putatively increasing susceptibility to HIV acquisition, as in the case of schistosomiasis, to decreasing risk of protozoal infections through pharmacokinetic interactions between antiretroviral therapy and antiparasitic agents, as in the case of malaria. However, despite this intimate interplay in pathophysiology and a broad overlap in epidemiology, there is a general paucity of data on the interactions between HIV and tropical parasitic infections, particularly in the era of widespread antiretroviral therapy availability. SUMMARY Additional data are needed to motivate clinical recommendations for detection and management of parasitic infections in HIV-infected individuals, and to consider the implications of and potential opportunity granted by HIV treatment programs on parasitic disease control.
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Affiliation(s)
| | - Mark J Siedner
- Massachusetts General Hospital
- Harvard Medical School
- Mbarara University of Science and Technology
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Weisman Z, Kalinkovich A, Stein M, Greenberg Z, Borkow G, Adlerstein D, Mahdi JA, Bentwich Z. Effects of Helminth Eradication on the Immune System. Pathog Immun 2017; 2:293-307. [PMID: 30993247 PMCID: PMC6423624 DOI: 10.20411/pai.v2i2.205] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Introduction: Helminth infection has a profound effect on the immune system. However, the precise nature of the immune changes that are elicited by helminth infection have not been sufficiently characterized. Furthermore, the reversibility of these changes after treatment has not been documented sufficiently. We studied the immune profiles of Ethiopian immigrants to Israel at baseline, that is on arrival and at one-year follow-up and compared individuals who received antihelminth treatment during the study period with those who missed the treatment. Methods: A longitudinal follow up study involving different groups of subjects was conducted. Baseline data was recorded from the newly arrived Ethiopian immigrants for a series of peripheral blood tests, including: IgE and Eosinophil levels, T-cell populations, T-cell receptor phenotypes, and cytokine measurement. These tests were all repeated after a 1-year interval. Results were compared between the newly arrived Ethiopian immigrants (NEW-Eth-Il), long term Ethiopian immigrants (LT-Eth-Il), and non Ethiopian Israeli controls (NON-Imm-Il). Results: Of the 184 individuals, 111 were NEW-Eth-Il, who had a high prevalence of helminth infection, the immunological changes were elevated IgE levels and eosinophil counts, decreased CD4/CD8 ratio, increased proportion of HLA-DR+CD3+, HLA-DR+CD4+ and HLA-DR+CD8+ cells, decreased proportion of CD45RA+CD4+ (naive) and CD28+CD8+ cells, increased proportion of CD45RO+CD4+ (memory) cells, and increased secretion of IL-4 and IL-5 (Th2 type cytokines). In the 42 LT-Eth-Il participants, who all had negative tests for helminth infection, we did not observe these immune changes and their immune profile did not differ markedly from that of the NON-Imm-Il controls. The follow-up immune profiles of 33 NEW-Eth-Il who received succesful antihelminth treatment, showed a significant normalization in the above-mentioned variables that was not observed in the 19 NEW-Eth-Il who missed and did not receive the antihelminth treatment. Conclusions: These findings demonstrate that helminth infection is associated with profound immune changes that are normalized within a short time after helminth eradication. They also strengthen the hypothesis that effective antihelminth interventions, in areas endemic for intestinal helminths, may have an impact on AIDS and tuberculosis epidemics.
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Affiliation(s)
- Ziva Weisman
- Kaplan Medical Center, Ben-Ari Institute of Clinical Immunology and AIDS Center, Rehovot, Israel
| | - Alexander Kalinkovich
- Hebrew University Hadassah Medical School, Jerusalem, Israel.,Public Health Laboratory, Ministry of Health, Jerusalem, Israel
| | - Miguel Stein
- Hebrew University Hadassah Medical School, Jerusalem, Israel
| | - Zalman Greenberg
- Hebrew University Hadassah Medical School, Jerusalem, Israel.,Public Health Laboratory, Ministry of Health, Jerusalem, Israel
| | - Gad Borkow
- Kaplan Medical Center, Ben-Ari Institute of Clinical Immunology and AIDS Center, Rehovot, Israel
| | - David Adlerstein
- Kaplan Medical Center, Ben-Ari Institute of Clinical Immunology and AIDS Center, Rehovot, Israel.,Department of Microbiology Immunology and Genetics, Center for Emerging and Tropical Diseases and AIDS, Ben Gurion University of the Negev, Beer Sheba, Israel
| | - Jemal Ali Mahdi
- Department of Microbiology, Immunology and Parasitology, College of Medicine and Health Sciences, University of Gondar, Gondar, Ethiopia.,Department of Microbiology Immunology and Genetics, Center for Emerging and Tropical Diseases and AIDS, Ben Gurion University of the Negev, Beer Sheba, Israel
| | - Zvi Bentwich
- Kaplan Medical Center, Ben-Ari Institute of Clinical Immunology and AIDS Center, Rehovot, Israel.,Department of Microbiology Immunology and Genetics, Center for Emerging and Tropical Diseases and AIDS, Ben Gurion University of the Negev, Beer Sheba, Israel
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7
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Morawski BM, Yunus M, Kerukadho E, Turyasingura G, Barbra L, Ojok AM, DiNardo AR, Sowinski S, Boulware DR, Mejia R. Hookworm infection is associated with decreased CD4+ T cell counts in HIV-infected adult Ugandans. PLoS Negl Trop Dis 2017; 11:e0005634. [PMID: 28542260 PMCID: PMC5462474 DOI: 10.1371/journal.pntd.0005634] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2016] [Revised: 06/07/2017] [Accepted: 05/10/2017] [Indexed: 01/02/2023] Open
Abstract
Most studies evaluating epidemiologic relationships between helminths and HIV have been conducted in the pre-ART era, and evidence of the impact of helminth infections on HIV disease progression remains conflicting. Less is known about helminth infection and clinical outcomes in HIV-infected adults receiving antiretroviral therapy (ART). We sampled HIV-infected adults for eight gastrointestinal parasites and correlated parasitic infection with demographic predictors, and clinical and immunologic outcomes. Contrasting with previous studies, we measured parasitic infection with a quantitative, highly sensitive and specific polymerase chain reaction (PCR) method. This cohort study enrolled HIV-infected Ugandans from August-September 2013 in Mbale, Uganda and collected stool and blood samples at enrollment. Real-time PCR quantified stool: Ascaris lumbricoides, Ancylostoma duodenale, Necator americanus, Strongyloides stercoralis, Trichuris trichiura, Cryptosporidium spp., Entamoeba histolytica, and Giardia intestinalis infection. Generalized linear models assessed relationships between parasitic infection and clinical or demographic data. 35% of participants (71/202) tested positive for ≥1 helminth, mainly N. americanus (55/199, 28%), and 4.5% (9/202) were infected with ≥2 stool parasites. Participants with hookworm infection had lower average CD4+ cell counts (-94 cells/mcL, 95%CI: -141, -48 cells/mcL; p<0.001) after adjustment for sex, CD4+ nadir at clinic entry, and time on ART. The high prevalence of parasitic infection and correlation with decreased CD4+ concentrations highlight the need to re-examine the effects of invasive helminth co-infection in rural, HIV-infected populations in the era of widely available ART. Elucidating the relationship between hookworm infection and immune recovery could provide opportunities for health optimization, e.g. integrated deworming, in these vulnerable populations.
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Affiliation(s)
- Bozena M. Morawski
- Division of Epidemiology and Community Health, School of Public Health, University of Minnesota, Minneapolis, MN, United States of America
- Division of Infectious Diseases and International Medicine, Department of Medicine, University of Minnesota, Minneapolis, MN, United States of America
| | - Miya Yunus
- The AIDS Support Organization, Kampala, Uganda
| | | | | | | | | | - Andrew R. DiNardo
- Division of Global and Immigrant Health, Department of Pediatrics, Baylor College of Medicine, Houston, TX, United States of America
| | - Stefanie Sowinski
- Infectious Diseases Institute, Makerere University, Kampala, Uganda
- The Gladstone Institute of Virology and Immunology, University of California, San Francisco, San Francisco, CA, United States of America
| | - David R. Boulware
- Division of Epidemiology and Community Health, School of Public Health, University of Minnesota, Minneapolis, MN, United States of America
- Division of Infectious Diseases and International Medicine, Department of Medicine, University of Minnesota, Minneapolis, MN, United States of America
| | - Rojelio Mejia
- Section of Tropical Medicine, Department of Pediatrics, National School of Tropical Medicine, Baylor College of Medicine, Houston, TX, United States of America
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9
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Dietze KK, Dittmer U, Koudaimi DK, Schimmer S, Reitz M, Breloer M, Hartmann W. Filariae-Retrovirus Co-infection in Mice is Associated with Suppressed Virus-Specific IgG Immune Response and Higher Viral Loads. PLoS Negl Trop Dis 2016; 10:e0005170. [PMID: 27923052 PMCID: PMC5140070 DOI: 10.1371/journal.pntd.0005170] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2016] [Accepted: 11/07/2016] [Indexed: 12/22/2022] Open
Abstract
Worldwide more than 2 billion people are infected with helminths, predominantly in developing countries. Co-infections with viruses such as human immunodeficiency virus (HIV) are common due to the geographical overlap of these pathogens. Helminth and viral infections induce antagonistic cytokine responses in their hosts. Helminths shift the immune system to a type 2-dominated immune response, while viral infections skew the cytokine response towards a type 1 immune response. Moreover, chronic helminth infections are often associated with a generalized suppression of the immune system leading to prolonged parasite survival, and also to a reduced defence against unrelated pathogens. To test whether helminths affect the outcome of a viral infection we set up a filarial/retrovirus co-infection model in C57BL/6 mice. Although Friend virus (FV) infection altered the L. sigmodontis-specific immunoglobulin response towards a type I associated IgG2 isotype in co-infected mice, control of L. sigmodontis infection was not affected by a FV-superinfection. However, reciprocal control of FV infection was clearly impaired by concurrent L. sigmodontis infection. Spleen weight as an indicator of pathology and viral loads in spleen, lymph nodes (LN) and bone marrow (BM) were increased in L. sigmodontis/FV-co-infected mice compared to only FV-infected mice. Numbers of FV-specific CD8+ T cells as well as cytokine production by CD4+ and CD8+ cells were alike in co-infected and FV-infected mice. Increased viral loads in co-infected mice were associated with reduced titres of neutralising FV-specific IgG2b and IgG2c antibodies. In summary our findings suggest that helminth infection interfered with the control of retroviral infection by dampening the virus-specific neutralising antibody response. The coincidental infection of a host with two different pathogens is widespread in low-income countries. Regions where helminth infections are endemic strongly overlap with areas where the incidence of viral infections such as HIV is high. HIV is a major public health issue causing more than 1 million deaths per year. To analyse the impact of a pre-existing helminth infection on a viral infection we established a helminth/retrovirus co-infection mouse model. Mice that were first infected with Litomosoides sigmodontis and subsequently with a murine retrovirus showed a more severe course of virus infection, i.e. exaggerated splenomegaly and higher viral loads. Since different lymphocytes such as B and T cells contribute to viral control we analysed the cellular and humoral immune response. While T cell responses were similar in co-infected and virus-infected mice, we observed reduced titres of virus-specific antibodies in co-infected mice. Our results suggest that helminth infection interfered with viral control by dampening the virus-specific antibody response. The viral infection itself altered the humoral immune response against L. sigmodontis without changing the worm burden. In summary, our data highlight the importance of deworming programs or vaccines against helminths in developing countries where the incidence of helminth/HIV co-infections is high.
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Affiliation(s)
- Kirsten Katrin Dietze
- Institute of Virology, University Hospital Essen, University of Duisburg-Essen, Essen, Germany
| | - Ulf Dittmer
- Institute of Virology, University Hospital Essen, University of Duisburg-Essen, Essen, Germany
| | - Daniel Karim Koudaimi
- Institute of Virology, University Hospital Essen, University of Duisburg-Essen, Essen, Germany
| | - Simone Schimmer
- Institute of Virology, University Hospital Essen, University of Duisburg-Essen, Essen, Germany
| | - Martina Reitz
- Bernhard Nocht Institute for Tropical Medicine, Hamburg, Germany
| | - Minka Breloer
- Bernhard Nocht Institute for Tropical Medicine, Hamburg, Germany
| | - Wiebke Hartmann
- Bernhard Nocht Institute for Tropical Medicine, Hamburg, Germany
- * E-mail:
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Blanquart F, Grabowski MK, Herbeck J, Nalugoda F, Serwadda D, Eller MA, Robb ML, Gray R, Kigozi G, Laeyendecker O, Lythgoe KA, Nakigozi G, Quinn TC, Reynolds SJ, Wawer MJ, Fraser C. A transmission-virulence evolutionary trade-off explains attenuation of HIV-1 in Uganda. eLife 2016; 5:e20492. [PMID: 27815945 PMCID: PMC5115872 DOI: 10.7554/elife.20492] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2016] [Accepted: 11/01/2016] [Indexed: 01/25/2023] Open
Abstract
Evolutionary theory hypothesizes that intermediate virulence maximizes pathogen fitness as a result of a trade-off between virulence and transmission, but empirical evidence remains scarce. We bridge this gap using data from a large and long-standing HIV-1 prospective cohort, in Uganda. We use an epidemiological-evolutionary model parameterised with this data to derive evolutionary predictions based on analysis and detailed individual-based simulations. We robustly predict stabilising selection towards a low level of virulence, and rapid attenuation of the virus. Accordingly, set-point viral load, the most common measure of virulence, has declined in the last 20 years. Our model also predicts that subtype A is slowly outcompeting subtype D, with both subtypes becoming less virulent, as observed in the data. Reduction of set-point viral loads should have resulted in a 20% reduction in incidence, and a three years extension of untreated asymptomatic infection, increasing opportunities for timely treatment of infected individuals.
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Affiliation(s)
- François Blanquart
- MRC Centre for Outbreak Analysis and Modelling, Imperial College London, London, United Kingdom
- Department of Infectious Disease Epidemiology, Imperial College London, London, United Kingdom
- School of Public Health, Imperial College London, London, United Kingdom
| | - Mary Kate Grabowski
- Department of Epidemiology, Johns Hopkins University, Baltimore, United States
- Bloomberg School of Public Health, Johns Hopkins University, Baltimore, United States
| | - Joshua Herbeck
- International Clinical Research Center, University of Washington, Seattle, United States
- Department of Global Health, University of Washington, Seattle, United States
| | | | - David Serwadda
- Rakai Health Sciences Program, Entebbe, Uganda
- School of Public Health, Makerere University, Kampala, Uganda
| | - Michael A Eller
- U.S. Military HIV Research Program, Walter Reed Army Institute of Research, Silver Spring, United States
- Henry M. Jackson Foundation for the Advancement of Military Medicine, Bethesda, United States
| | - Merlin L Robb
- U.S. Military HIV Research Program, Walter Reed Army Institute of Research, Silver Spring, United States
- Henry M. Jackson Foundation for the Advancement of Military Medicine, Bethesda, United States
| | - Ronald Gray
- Department of Epidemiology, Johns Hopkins University, Baltimore, United States
- Bloomberg School of Public Health, Johns Hopkins University, Baltimore, United States
- Rakai Health Sciences Program, Entebbe, Uganda
| | | | - Oliver Laeyendecker
- Laboratory of Immunoregulation, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, United States
- Division of Intramural Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, United States
| | - Katrina A Lythgoe
- MRC Centre for Outbreak Analysis and Modelling, Imperial College London, London, United Kingdom
- Department of Infectious Disease Epidemiology, Imperial College London, London, United Kingdom
- School of Public Health, Imperial College London, London, United Kingdom
- Department of Zoology, University of Oxford, Oxford, United Kingdom
| | | | - Thomas C Quinn
- Laboratory of Immunoregulation, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, United States
- Division of Intramural Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, United States
| | - Steven J Reynolds
- Laboratory of Immunoregulation, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, United States
- Division of Intramural Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, United States
| | - Maria J Wawer
- Department of Epidemiology, Johns Hopkins University, Baltimore, United States
- Bloomberg School of Public Health, Johns Hopkins University, Baltimore, United States
| | - Christophe Fraser
- MRC Centre for Outbreak Analysis and Modelling, Imperial College London, London, United Kingdom
- Department of Infectious Disease Epidemiology, Imperial College London, London, United Kingdom
- School of Public Health, Imperial College London, London, United Kingdom
- Big Data Institute, Li Ka Shing Centre for Health Information and Discovery, Nuffield Department of Medicine, University of Oxford, Oxford, United Kingdom
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11
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Abstract
BACKGROUND Helminth infections, such as soil-transmitted helminths, schistosomiasis, onchocerciasis, and lymphatic filariasis, are prevalent in many countries where human immunodeficiency virus (HIV) infection is also common. There is some evidence from observational studies that HIV and helminth co-infection may be associated with higher viral load and lower CD4+ cell counts. Treatment of helminth infections with antihelminthics (deworming drugs) may have benefits for people living with HIV beyond simply clearance of worm infections.This is an update of a Cochrane Review published in 2009 and we have expanded it to include outcomes of anaemia and adverse events. OBJECTIVES To evaluate the effects of deworming drugs (antihelminthic therapy) on markers of HIV disease progression, anaemia, and adverse events in children and adults. SEARCH METHODS In this review update, we searched online for published and unpublished studies in the Cochrane Library, MEDLINE, EMBASE, CENTRAL, the World Health Organization (WHO) International Clinical Trials Registry Platform (ICRTP), ClinicalTrials.gov, and the WHO Global Health Library up to 29 September 2015. We also searched databases listing conference abstracts, scanned reference lists of articles, and contacted the authors of included studies. SELECTION CRITERIA We searched for randomized controlled trials (RCTs) that compared antihelminthic drugs with placebo or no intervention in HIV-positive people. DATA COLLECTION AND ANALYSIS Two review authors independently extracted data and assessed trials for eligibility and risk of bias. The primary outcomes were changes in HIV viral load and CD4+ cell count, and secondary outcomes were anaemia, iron deficiency, adverse events, and mortality events. We compared the effects of deworming using mean differences, risk ratios (RR), and 95% confidence intervals (CIs). We assessed the quality of evidence using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach. MAIN RESULTS Eight trials met the inclusion criteria of this review, enrolling a total of 1612 participants. Three trials evaluated the effect of providing antihelminthics to all adults with HIV without knowledge of their helminth infection status, and five trials evaluated the effects of providing deworming drugs to HIV-positive individuals with confirmed helminth infections. Seven trials were conducted in sub-Saharan Africa and one in Thailand. Antihelminthics for people with unknown helminth infection statusProviding antihelminthics (albendazole and praziquantel together or separately) to HIV-positive adults with unknown helminth infection status may have a small suppressive effect on mean viral load at six weeks but the 95% CI includes the possibility of no effect (difference in mean change -0.14 log10 viral RNA/mL, 95% CI -0.35 to 0.07, P = 0.19; one trial, 166 participants, low quality evidence).Repeated dosing with deworming drugs over two years (albendazole every three months plus annual praziquantel), probably has little or no effect on mean viral load (difference in mean change 0.01 log10 viral RNA, 95% CI: -0.03 to -0.05; one trial, 917 participants, moderate quality evidence), and little or no effect on mean CD4+ count (difference in mean change 2.60 CD4+ cells/µL, 95% CI -10.15 to 15.35; P = 0.7; one trial, 917 participants, low quality evidence). Antihelminthics for people with confirmed helminth infectionsTreating confirmed helminth infections in HIV-positive adults may have a small suppressive effect on mean viral load at six to 12 weeks following deworming (difference in mean change -0.13 log10 viral RNA, 95% CI -0.26 to -0.00; P = 0.04; four trials, 445 participants, low quality evidence). However, this finding is strongly influenced by a single study of praziquantel treatment for schistosomiasis. There may also be a small favourable effect on mean CD4+ cell count at 12 weeks after deworming in HIV-positive populations with confirmed helminth infections (difference in mean change 37.86 CD4+ cells/µL, 95% CI 7.36 to 68.35; P = 0.01; three trials, 358 participants, low quality evidence). Adverse events and mortality There is no indication that antihelminthic drugs impart additional risks in HIV-positive populations. However, adverse events were not well reported (very low quality evidence) and trials were underpowered to evaluate effects on mortality (low quality evidence). AUTHORS' CONCLUSIONS There is low quality evidence that treating confirmed helminth infections in HIV-positive adults may have small, short-term favourable effects on markers of HIV disease progression. Further studies are required to confirm this finding. Current evidence suggests that deworming with antihelminthics is not harmful, and this is reassuring for the routine treatment of confirmed or suspected helminth infections in people living with HIV in co-endemic areas.Further long-term studies are required to make confident conclusions regarding the impact of presumptively deworming all HIV-positive individuals irrespective of helminth infection status, as the only long-term trial to date did not demonstrate an effect.
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Affiliation(s)
| | - Paul Burns
- University of WashingtonDepartment of Global HealthSeattleWashingtonUSA
| | - David Sinclair
- Liverpool School of Tropical MedicineDepartment of Clinical SciencesPembroke PlaceLiverpoolUKL3 5QA
| | - Judd L Walson
- University of WashingtonDepartments of Global Health, Medicine (Infectious Disease) and Pediatrics, EpidemiologyBox 359909325 Ninth AvenueSeattleWAUSA98104
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Adeleke OA, Yogeswaran P, Wright G. Intestinal helminth infections amongst HIV-infected adults in Mthatha General Hospital, South Africa. Afr J Prim Health Care Fam Med 2015; 7:910. [PMID: 26842519 PMCID: PMC4729221 DOI: 10.4102/phcfm.v7i1.910] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2015] [Revised: 10/28/2015] [Accepted: 09/27/2015] [Indexed: 01/16/2023] Open
Abstract
Background In South Africa, studies on the prevalence of intestinal helminth co-infection amongst HIV-infected patients as well as possible interactions between these two infections are limited. Aim To investigate the prevalence of intestinal helminth infestation amongst adults living with HIV or AIDS at Mthatha General Hospital. Setting Study participants were recruited at the outpatient department of Mthatha General Hospital, Mthatha, South Africa. Methods This cross-sectional study was conducted between October and December 2013 amongst consecutive consenting HIV-positive adult patients. Socio-demographic and clinical information were obtained using data collection forms and structured interviews. Stool samples were collected to investigate the presence of helminths whilst blood samples were obtained for the measurement of CD4+ T-cell count and viral load. Results Data were obtained on 231 participants, with a mean age of 34.9 years, a mean CD4 count of 348 cells/µL and a mean viral load of 4.8 log10 copies/mL. Intestinal helminth prevalence was 24.7%, with Ascaris Lumbricoides (42.1%) the most prevalent identified species. Statistically significant association was found between CD4 count of less than 200 cells/µL and helminth infection (p = 0.05). No statistically significant association was found between intestinal helminth infection and the mean CD4 count (p = 0.79) or the mean viral load (p = 0.98). Conclusion A high prevalence of intestinal helminth infections was observed amongst the study population. Therefore, screening and treatment of helminths should be considered as part of the management of HIV and AIDS in primary health care.
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Abossie A, Petros B. Deworming and the immune status of HIV positive pre-antiretroviral therapy individuals in Arba Minch, Chencha and Gidole hospitals, Southern Ethiopia. BMC Res Notes 2015; 8:483. [PMID: 26415705 PMCID: PMC4585997 DOI: 10.1186/s13104-015-1461-9] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2014] [Accepted: 09/21/2015] [Indexed: 11/25/2022] Open
Abstract
Background Helminths/HIV co-infections are very common in developing countries, especially in Africa. The effect of overlapping distribution of HIV and helminths becomes important because concomitant infection may exacerbate disease outcome of HIV infection. The study aimed at determining the effect of deworming on the immune status of helminth/HIV coinfected Pre-ART HIV patients attending three health institutions in Southern Ethiopia. Methods 97 HIV-positive Pre-ART individuals were observed into 2 groups on the basis of helminth co-infection and no infection. Out of these, 66 study participants were helminths/HIV co-infected and the remaining 31 study participants were helminths (−)/HIV (+) control. Helminth/HIV co-infected participants CD4+ T-cell count was done at baseline, after 15 weeks and 6 months after antihelminthics treatment. Data were analyzed using SPSS version 16. Results Ascaris lumbricoides was the highest prevalent soil transmitted helminths in Pre-ART individuals in this study. CD4+ T-cell count in the Ascaris lumricoides/HIV co-infected was significantly higher (P = 0.05) and (P < 0.05) after 15 weeks and 6 months post-antihelminthics treatment respectively. Also, after antihelminthic therapy, the CD4+ T-cell count significantly increased (P < 0.005) in all treated helminth infections. Conclusions The study showed that treatment of ascariasis had a significant effect on CD4+ T-cell count increase in the treated Pre-ART Ascaris lumbricoides/HIV co-infected individuals; whereas the same positive effect was not evident for other intestinal helminth parasites detected in the study. In conclusion, this finding on Ascaris lumbricoides-specific nature of immune interaction in helminth/HIV co-infection may partly explain the inconsistent reports on the role of intestinal helminths on progression of HIV infection to AIDS. Therefore, a well-designed longitudinal study on helminth species-specific HIV/helminth co-infection will be needed to fully establish the possible benefits of deworming in intestinal helminth/HIV co-infection.
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Affiliation(s)
- Ashenafi Abossie
- Medical Laboratory Technology Team, Arba Minch College of Health Sciences, P. O. Box 155, Arba Minch, Ethiopia. .,Department of Microbial, Cellular and Molecular Biology, College of Natural Sciences, Addis Ababa University, P.O. Box. 1176, Addis Ababa, Ethiopia.
| | - Beyene Petros
- Department of Microbial, Cellular and Molecular Biology, College of Natural Sciences, Addis Ababa University, P.O. Box. 1176, Addis Ababa, Ethiopia.
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Talaat KR, Babu S, Menon P, Kumarasamy N, Sharma J, Arumugam J, Dhakshinamurthy K, Srinivasan R, Poongulali S, Gu W, Fay MP, Swaminathan S, Nutman TB. Treatment of W. bancrofti (Wb) in HIV/Wb coinfections in South India. PLoS Negl Trop Dis 2015; 9:e0003622. [PMID: 25793933 PMCID: PMC4368731 DOI: 10.1371/journal.pntd.0003622] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2014] [Accepted: 02/13/2015] [Indexed: 11/30/2022] Open
Abstract
Background The disease course of human immunodeficiency virus (HIV) is often altered by existing or newly acquired coincident infections. Methodology/Principal Findings To assess the influence of pre-existing Wuchereria bancrofti infection on HIV progression, we performed a case-controlled treatment study of HIV positive individuals with (FIL+) or without (FIL-) W. bancrofti infection. Twenty-eight HIV+/FIL+ and 51 matched HIV+/FIL- subjects were treated with a single dose of diethylcarbamazine and albendazole (DEC/Alb) and followed for a year at regular intervals. Sixteen of the HIV+/FIL+ subjects (54%) and 28 of the HIV+/FIL- controls (57%) were on antiretroviral therapy (ART) during the study. Following treatment, no differences were noted in clinical outcomes between the 2 groups. There also was no significant difference between the groups in the HIV viral load at 12 months as a percentage of baseline viral load (HIV+/FIL+ group had on average 0.97 times the response of the HIV+/FIL- group, 95% CI 0.88, 1.07) between the groups. Furthermore, there were no significant differences found in either the change in viral load at 1, 3, or 6 months or in the change in CD4 count at 3, 6, or 12 months between the 2 groups. Conclusions/Significance We were unable to find a significant effect of W. bancrofti infection or its treatment on HIV clinical course or surrogate markers of HIV disease progression though we recognized that our study was limited by the smaller than predicted sample size and by the use of ART in half of the patients. Treatment of W. bancrofti coinfection in HIV positive subjects (as is usual in mass drug administration campaigns) did not represent an increased risk to the subjects, and should therefore be considered for PLWHA living in W. bancrofti endemic areas. Trial Registration ClinicalTrials.gov NCT00344279 In people living with HIV infection, simultaneous infections can adversely affect HIV disease. This has been seen with bacterial (tuberculosis), viral (cytomegalovirus), and parasitic infections (toxoplasmosis). Lymphatic filariasis is caused by a thin thread-like parasite that lives in the lymph vessels of infected people. It can cause significant disability. This infection is found in much of the same areas that high levels of HIV infection. We were interested in knowing if lymphatic filariasis changed the course of HIV infection in people with both diseases. In this study, the authors enrolled people in India who were living with HIV who either had or didn’t have filarial infection. All patients were treated for filariasis with 2 drugs, and then were followed for 1 year to see how their HIV disease progressed. No difference in HIV disease progression was found between the groups that did or did not have filariasis before treatment. The patients with HIV did well with the medicine for filariasis.
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Affiliation(s)
- Kawsar R. Talaat
- Laboratory of Parasitic Diseases, National Institute of Allergy and Infectious Disease, National Institutes of Health, Bethesda, Maryland, United States of America
- Department of International Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, United States of America
- * E-mail:
| | - Subash Babu
- Department of International Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, United States of America
| | - Pradeep Menon
- National Institute for Research in Tuberculosis (formerly Tuberculosis Research Centre), Indian Council of Medical Research, Chennai, India
| | | | | | | | - Kalaivani Dhakshinamurthy
- National Institute for Research in Tuberculosis (formerly Tuberculosis Research Centre), Indian Council of Medical Research, Chennai, India
| | - Ramalingam Srinivasan
- National Institute for Research in Tuberculosis (formerly Tuberculosis Research Centre), Indian Council of Medical Research, Chennai, India
| | | | - Wenjuan Gu
- Division of Clinical Research, National Institute of Allergy and Infectious Diseases, Bethesda, Maryland, United States of America
| | - Michael P. Fay
- Division of Clinical Research, National Institute of Allergy and Infectious Diseases, Bethesda, Maryland, United States of America
| | - Soumya Swaminathan
- National Institute for Research in Tuberculosis (formerly Tuberculosis Research Centre), Indian Council of Medical Research, Chennai, India
| | - Thomas B. Nutman
- Department of International Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, United States of America
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Lankowski AJ, Tsai AC, Kanyesigye M, Bwana M, Haberer JE, Wenger M, Martin JN, Bangsberg DR, Hunt PW, Siedner MJ. Empiric deworming and CD4 count recovery in HIV-infected Ugandans initiating antiretroviral therapy. PLoS Negl Trop Dis 2014; 8:e3036. [PMID: 25101890 PMCID: PMC4125278 DOI: 10.1371/journal.pntd.0003036] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2013] [Accepted: 06/09/2014] [Indexed: 12/19/2022] Open
Abstract
BACKGROUND There is conflicting evidence on the immunologic benefit of treating helminth co-infections ("deworming") in HIV-infected individuals. Several studies have documented reduced viral load and increased CD4 count in antiretroviral therapy (ART) naïve individuals after deworming. However, there are a lack of data on the effect of deworming therapy on CD4 count recovery among HIV-infected persons taking ART. METHODOLOGY/PRINCIPAL FINDINGS To estimate the association between empiric deworming therapy and CD4 count after ART initiation, we performed a retrospective observational study among HIV-infected adults on ART at a publicly operated HIV clinic in southwestern Uganda. Subjects were assigned as having received deworming if prescribed an anti-helminthic agent between 7 and 90 days before a CD4 test. To estimate the association between deworming and CD4 count, we fit multivariable regression models and analyzed predictors of CD4 count, using a time-by-interaction term with receipt or non-receipt of deworming. From 1998 to 2009, 5,379 subjects on ART attended 21,933 clinic visits at which a CD4 count was measured. Subjects received deworming prior to 668 (3%) visits. Overall, deworming was not associated with a significant difference in CD4 count in either the first year on ART (β = 42.8; 95% CI, -2.1 to 87.7) or after the first year of ART (β = -9.9; 95% CI, -24.1 to 4.4). However, in a sub-analysis by gender, during the first year of ART deworming was associated with a significantly greater rise in CD4 count (β = 63.0; 95% CI, 6.0 to 120.1) in females. CONCLUSIONS/SIGNIFICANCE Empiric deworming of HIV-infected individuals on ART conferred no significant generalized benefit on subsequent CD4 count recovery. A significant association was observed exclusively in females and during the initial year on ART. Our findings are consistent with recent studies that failed to demonstrate an immunologic advantage to empirically deworming ART-naïve individuals, but suggest that certain sub-populations may benefit.
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Affiliation(s)
- Alexander J. Lankowski
- Department of Internal Medicine, Hospital of the University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
- Department of Pediatrics, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania, United States of America
- Center for Global Health, Massachusetts General Hospital, Boston, Massachusetts, United States of America
- * E-mail:
| | - Alexander C. Tsai
- Center for Global Health, Massachusetts General Hospital, Boston, Massachusetts, United States of America
- Chester M. Pierce MD Division of Global Psychiatry, Department of Psychiatry, Massachusetts General Hospital, Boston, Massachusetts, United States of America
| | | | - Mwebesa Bwana
- Mbarara University of Science and Technology, Mbarara, Uganda
| | - Jessica E. Haberer
- Center for Global Health, Massachusetts General Hospital, Boston, Massachusetts, United States of America
| | - Megan Wenger
- University of California, San Francisco, San Francisco, California, United States of America
| | - Jeffrey N. Martin
- University of California, San Francisco, San Francisco, California, United States of America
| | - David R. Bangsberg
- Center for Global Health, Massachusetts General Hospital, Boston, Massachusetts, United States of America
- Mbarara University of Science and Technology, Mbarara, Uganda
- Ragon Institute of Massachusetts General Hospital, Massachusetts Institute of Technology, and Harvard Medical School, Boston, Massachusetts, United States of America
| | - Peter W. Hunt
- University of California, San Francisco, San Francisco, California, United States of America
| | - Mark J. Siedner
- Center for Global Health, Massachusetts General Hospital, Boston, Massachusetts, United States of America
- Division of Infectious Diseases, Department of Medicine, Massachusetts General Hospital, Boston, Massachusetts, United States of America
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Bustinduy A, King C, Scott J, Appleton S, Sousa-Figueiredo JC, Betson M, Stothard JR. HIV and schistosomiasis co-infection in African children. THE LANCET. INFECTIOUS DISEASES 2014; 14:640-9. [DOI: 10.1016/s1473-3099(14)70001-5] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Mulu A, Maier M, Liebert UG. Triple NF-kB binding sites and LTR sequence similarities in HIV-1C isolates irrespective of helminth co-infection. Parasit Vectors 2014; 7:204. [PMID: 24774967 PMCID: PMC4013539 DOI: 10.1186/1756-3305-7-204] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2014] [Accepted: 04/25/2014] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Helminth infections as well as structural alternations in the long-terminal repeat (LTR) regions of HIV-1 are known to contribute to elevated HIV RNA level and enhance HIV-1 diseases progression. However, the impact of helminths infections on the occurrences of triple NF-κB and genetic variability in LTR region of HIV-1C isolates is not known. We aimed to examine the presence of genetic variability in the LTR region of HIV-1C isolates during chronic HIV-helminth co-infection. METHODS HIV-1C infected Ethiopians with (n = 22) and without (n = 20) helminth infection were included. The LTR region of HIV was amplified and sequenced. Sequences were aligned with reference set from the Los Alamos HIV database. Phylogenetic analysis and frequency of polymorphic changes was performed by the neighbour-joining method using Geneious Basic software. RESULTS All LTR sequences from patients with or without of helminth co-infection clustered with HIV-1 subtype C with two distinct subclusters (C and C'). The enhancer element was found to have three copies of 10-base pair binding sites for NF-κBs which is an evidence for predominance of triple NF-κB sites (94%) in HIV-1C isolates irrespective of helminths co-infection and subclusters. Moreover, irrespective of helminth co-infection and C/C' subclusters high sequences similarity in LTR was observed. There was no significant difference in plasma HIV RNA level between HIV-1 C and C' subclusters. CONCLUSIONS Despite the small sample size, the predominance of triple NF-κB binding sites and high sequence similarities in LTR region irrespective of helminths infection suggest the natural occurrence of the three NF-κB binding sites in HIV-1C isolates without the influence of secondary infection. Thus, the higher HIV-1C viraemia in helminth co-infected individuals is more likely a result of immune activation rather than LTR sequence variation. Moreover, the lack of significant difference in plasma HIV RNA level between HIV-1 C and C' subcluster may show the lack of functional differences among the two groups.
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Affiliation(s)
- Andargachew Mulu
- Institute of Virology, Leipzig University, Johannisallee 30, Leipzig 04103, Germany.
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Mulu A, Maier M, Liebert UG. Deworming of intestinal helminths reduces HIV-1 subtype C viremia in chronically co-infected individuals. Int J Infect Dis 2013; 17:e897-901. [DOI: 10.1016/j.ijid.2013.03.022] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2013] [Revised: 03/22/2013] [Accepted: 03/25/2013] [Indexed: 11/29/2022] Open
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Abstract
Chronic infections with persistent pathogens such as helminths, mycobacteria, Plasmodium, and hepatitis viruses affect more than a third of the human population and are associated with increased susceptibility to other pathogens as well as reduced vaccine efficacy. Although these observations suggest an impact of chronic infections in modulating immunity to unrelated antigens, little is known regarding the underlying mechanisms. Here, we summarize evidence of the most prevalent infections affecting immunity to unrelated pathogens and vaccines, and discuss potential mechanisms of how different bystander chronic infections might impact immune responses. We suggest that bystander chronic infections affect different stages of host responses and may impact transmission and recognition of other pathogens, innate immune responses, priming and differentiation of adaptive effector responses, as well as the development and maintenance of immunological memory. Further understanding of the immunological effects of coinfection should provide opportunities to enhance vaccine efficacy and control of infectious diseases.
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Mazigo HD, Nuwaha F, Wilson S, Kinung'hi SM, Morona D, Waihenya R, Heukelbach J, Dunne DW. Epidemiology and interactions of Human Immunodeficiency Virus - 1 and Schistosoma mansoni in sub-Saharan Africa. Infect Dis Poverty 2013; 2:2. [PMID: 23849678 PMCID: PMC3707091 DOI: 10.1186/2049-9957-2-2] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2012] [Accepted: 01/17/2013] [Indexed: 11/28/2022] Open
Abstract
Human Immunodeficiency Virus-1/AIDS and Schistosoma mansoni are widespread in sub-Saharan Africa and co-infection occurs commonly. Since the early 1990s, it has been suggested that the two infections may interact and potentiate the effects of each other within co-infected human hosts. Indeed, S. mansoni infection has been suggested to be a risk factor for HIV transmission and progression in Africa. If so, it would follow that mass deworming could have beneficial effects on HIV-1 transmission dynamics. The epidemiology of HIV in African countries is changing, shifting from urban to rural areas where the prevalence of Schistosoma mansoni is high and public health services are deficient. On the other side, the consequent pathogenesis of HIV-1/S. mansoni co-infection remains unknown. Here we give an account of the epidemiology of HIV-1 and S. mansoni, discuss co-infection and possible biological causal relationships between the two infections, and the potential impact of praziquantel treatment on HIV-1 viral loads, CD4+ counts and CD4+/CD8+ ratio. Our review of the available literature indicates that there is evidence to support the hypothesis that S. mansoni infections can influence the replication of the HIV-1, cell-to-cell transmission, as well as increase HIV progression as measured by reduced CD4+ T lymphocytes counts. If so, then deworming of HIV positive individuals living in endemic areas may impact on HIV-1 viral loads and CD4+ T lymphocyte counts.
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Affiliation(s)
- Humphrey D Mazigo
- Department of Medical Parasitology and Entomology, School of Medicine, Catholic University of Health and Allied Sciences, P.O. Box 1464, Mwanza, Tanzania
- Department of Environmental Health and Communicable Disease Control, School of Public Health, College of Health Sciences, Makerere University, P.O. Box 7072, Kampala, Uganda
- National Institute for Medical Research, Mwanza Research Centre, P.O. Box 1462, Mwanza, Tanzania
- Department of Pathology, University of Cambridge, Tennis Court Road, Cambridge, CB2 1QP, UK
| | - Fred Nuwaha
- Department of Environmental Health and Communicable Disease Control, School of Public Health, College of Health Sciences, Makerere University, P.O. Box 7072, Kampala, Uganda
| | - Shona Wilson
- Department of Pathology, University of Cambridge, Tennis Court Road, Cambridge, CB2 1QP, UK
| | - Safari M Kinung'hi
- National Institute for Medical Research, Mwanza Research Centre, P.O. Box 1462, Mwanza, Tanzania
| | - Domenica Morona
- Department of Medical Parasitology and Entomology, School of Medicine, Catholic University of Health and Allied Sciences, P.O. Box 1464, Mwanza, Tanzania
| | - Rebecca Waihenya
- Department of Zoology, Faculty of Science, Jomo Kenyatta University of Agriculture and Technology, P.O. Box 62,000, 00200, Nairobi, Kenya
| | - Jorg Heukelbach
- Department of Community Health, School of Medicine, Federal University of Ceará, Ceará, Brazil
| | - David W Dunne
- Department of Pathology, University of Cambridge, Tennis Court Road, Cambridge, CB2 1QP, UK
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Downs JA, van Dam GJ, Changalucha JM, Corstjens PLAM, Peck RN, de Dood CJ, Bang H, Andreasen A, Kalluvya SE, van Lieshout L, Johnson WD, Fitzgerald DW. Association of Schistosomiasis and HIV infection in Tanzania. Am J Trop Med Hyg 2012; 87:868-73. [PMID: 23033399 DOI: 10.4269/ajtmh.2012.12-0395] [Citation(s) in RCA: 85] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
Animal and human studies suggest that Schistosoma mansoni infection may increase risk of human immunodeficiency virus (HIV) acquisition. Therefore, we tested 345 reproductive age women in rural Tanzanian villages near Lake Victoria, where S. mansoni is hyperendemic, for sexually transmitted infections (STIs) and schistosomiasis by circulating anodic antigen (CAA) serum assay. Over one-half (54%) had an active schistosome infection; 6% were HIV-seropositive. By univariate analysis, only schistosome infection predicted HIV infection (odds ratio [OR] = 3.9, 95% confidence interval = [1.3-12.0], P = 0.015) and remained significant using multivariate analysis to control for age, STIs, and distance from the lake (OR = 6.2 [1.7-22.9], P = 0.006). HIV prevalence was higher among women with more intense schistosome infections (P = 0.005), and the median schistosome intensity was higher in HIV-infected than -uninfected women (400 versus 15 pg CAA/mL, P = 0.01). This finding suggests that S. mansoni infection may be a modifiable HIV risk factor that places millions of people worldwide at increased risk of HIV acquisition.
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Affiliation(s)
- Jennifer A Downs
- Department of Medicine, Weill Cornell Medical College, New York, NY, USA.
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Mkhize-Kwitshana ZL, Mabaso MH. Can deworming delay immunosuppression in HIV? THE LANCET. INFECTIOUS DISEASES 2012; 12:899-900. [PMID: 22971324 DOI: 10.1016/s1473-3099(12)70231-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Abstract
PURPOSE OF REVIEW Helminths and HIV-1 use multiple mechanisms to avoid or deviate immune responses, and these mechanisms may interact with important consequences for the epidemiology of each infection. In this review, we summarize recent immunological and epidemiological advances in the understanding of HIV-1-helminth co-infections. RECENT FINDINGS Considering the extent of geographical overlap of these chronic infections, there has been so far surprisingly limited and inconsistent evidence of important interactive effects, either from epidemiological studies examining associations between helminth infection indicators and HIV disease parameters, or from studies that have dissected the immune mechanisms triggered by each pathogen in isolation and investigated their interaction. Systematic reviews have found inconsistent evidence for a beneficial effect of anthelmintic treatment of helminth-HIV-1 co-infected individuals on viral load or CD4 cell counts. It is not certain that co-infection with HIV-1 and helminths will always be more detrimental to the host than either single infection alone, or that intervening against co-infections will have only beneficial effects. SUMMARY A consensus on the implications of co-infection on de-worming and vaccination policies has not yet emerged. Well powered randomized trials in HIV-1-infected individuals with defined helminth infections are required to determine the benefits of anthelmintic interventions.
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Examining the relationship between urogenital schistosomiasis and HIV infection. PLoS Negl Trop Dis 2011; 5:e1396. [PMID: 22163056 PMCID: PMC3232194 DOI: 10.1371/journal.pntd.0001396] [Citation(s) in RCA: 131] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2011] [Accepted: 09/23/2011] [Indexed: 11/29/2022] Open
Abstract
Background Urogenital schistosomiasis, caused by infection with Schistosoma haematobium, is widespread and causes substantial morbidity on the African continent. The infection has been suggested as an unrecognized risk factor for incident HIV infection. Current guidelines recommend preventive chemotherapy, using praziquantel as a public health tool, to avert morbidity due to schistosomiasis. In individuals of reproductive age, urogenital schistosomiasis remains highly prevalent and, likely, underdiagnosed. This comprehensive literature review was undertaken to examine the evidence for a cause-effect relationship between urogenital schistosomiasis and HIV/AIDS. The review aims to support discussions of urogenital schistosomiasis as a neglected yet urgent public health challenge. Methodology/Principal Findings We conducted a systematic search of the literature including online databases, clinical guidelines, and current medical textbooks. We describe plausible local and systemic mechanisms by which Schistosoma haematobium infection could increase the risk of HIV acquisition in both women and men. We also detail the effects of S. haematobium infection on the progression and transmissibility of HIV in co-infected individuals. We briefly summarize available evidence on the immunomodulatory effects of chronic schistosomiasis and the implications this might have for populations at high risk of both schistosomiasis and HIV. Conclusions/Significance Studies support the hypothesis that urogenital schistosomiasis in women and men constitutes a significant risk factor for HIV acquisition due both to local genital tract and global immunological effects. In those who become HIV-infected, schistosomal co-infection may accelerate HIV disease progression and facilitate viral transmission to sexual partners. Establishing effective prevention strategies using praziquantel, including better definition of treatment age, duration, and frequency of treatment for urogenital schistosomiasis, is an important public health priority. Our findings call attention to this pressing yet neglected public health issue and the potential added benefit of scaling up coverage of schistosomal treatment for populations in whom HIV infection is prevalent. Urogenital schistosomiasis is a parasitic infection caused by a worm, Schistosoma haematobium, which lives in the bloodstream of infected individuals. It affects at least 112 million people, mostly in sub-Saharan Africa, and has been suggested to be a risk factor for becoming infected with HIV. We reviewed publications in order to examine whether it seems likely that this parasitic infection could be a risk factor for HIV. Evidence from many types of studies supports the hypothesis that urogenital schistosomiasis does increase a person's risk of becoming infected with HIV. Studies also suggest that individuals who have both urogenital schistosomiasis and HIV have a more aggressive HIV infection and can more easily transmit HIV to their sexual partners. Praziquantel is an oral, nontoxic, inexpensive medication that is safe in pregnancy and is recommended for treatment of schistosomiasis. In areas where both infections co-exist, regular administration of praziquantel both to young girls and to sexually-active women may be an important approach to reducing HIV transmission. Our findings support the importance of making praziquantel more available to people who live in areas of the world where both urogenital schistosomiasis and HIV infection are widespread.
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Linking global HIV/AIDS treatments with national programs for the control and elimination of the neglected tropical diseases. PLoS Negl Trop Dis 2011; 5:e1022. [PMID: 21814582 PMCID: PMC3144180 DOI: 10.1371/journal.pntd.0001022] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
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Ezenwa VO, Jolles AE. From host immunity to pathogen invasion: the effects of helminth coinfection on the dynamics of microparasites. Integr Comp Biol 2011; 51:540-51. [PMID: 21727178 DOI: 10.1093/icb/icr058] [Citation(s) in RCA: 109] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Concurrent infections with multiple parasites are ubiquitous in nature. Coinfecting parasites can interact with one another in a variety of ways, including through the host's immune system via mechanisms such as immune trade-offs and immunosuppression. These within-host immune processes mediating interactions among parasites have been described in detail, but how they scale up to determine disease dynamic patterns at the population level is only beginning to be explored. In this review, we use helminth-microparasite coinfection as a model for examining how within-host immunological effects may influence the ecological outcome of microparasitic diseases, with a specific focus on disease invasion. The current literature on coinfection between helminths and major microparasitic diseases includes many studies documenting the effects of helminths on individual host responses to microparasites. In many cases, the observed host responses map directly onto parameters relevant for quantifying disease dynamics; however, there have been few attempts at integrating data on individual-level effects into theoretical models to extrapolate from the individual to the population level. Moreover, there is considerable variability in the particular combination of disease parameters affected by helminths across different microparasite systems. We develop a conceptual framework identifying some potential sources of such variability: Pathogen persistence and severity, and resource availability to hosts. We also generate testable hypotheses regarding diseases and the environmental contexts when the effects of helminths on microparasite dynamics should be most pronounced. Finally, we use a case study of helminth and mycobacterial coinfection in the African buffalo to illustrate both progress and challenges in understanding the population-level consequences of within-host immunological interactions, and conclude with suggestions for future research that will help improve our understanding of the effects of coinfection on dynamics of infectious diseases.
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Affiliation(s)
- Vanessa O Ezenwa
- Odum School of Ecology, University of Georgia, Athens, GA 30602, USA.
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Species-specific treatment effects of helminth/HIV-1 co-infection: a systematic review and meta-analysis. Parasitology 2011; 138:1546-58. [PMID: 21729353 DOI: 10.1017/s0031182011000357] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
In sub-Saharan Africa, over 22 million people are estimated to be co-infected with both helminths and HIV-1. Several studies have suggested that de-worming individuals with HIV-1 may delay HIV-1 disease progression, and that the benefit of de-worming may vary by individual helminth species. We conducted a systematic review and meta-analysis of the published literature to determine the effect of treatment of individual helminth infections on markers of HIV-1 progression (CD4 count and HIV viral load). There was a trend towards an association between treatment for Schistosoma mansoni and a decrease in HIV viral load (Weighted mean difference (WMD)=-0·10; 95% Confidence interval (CI): -0·24, 0·03), although this association was not seen for Ascaris lumbricoides, hookworm or Trichuris trichiura. Treatment of A. lumbricoides, S. mansoni, hookworm or T. trichiura was not associated with a change in CD4 count. While pooled data from randomized trials suggested clinical benefit of de-worming for individual helminth species, these effects decreased when observational data were included in the pooled analysis. While further trials are needed to confirm the role of anthelmintic treatment in HIV-1 co-infected individuals, providing anthelmintics to individuals with HIV-1 may be a safe, inexpensive and practical intervention to slow progression of HIV-1.
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Hawley DM, Altizer SM. Disease ecology meets ecological immunology: understanding the links between organismal immunity and infection dynamics in natural populations. Funct Ecol 2011. [DOI: 10.1111/j.1365-2435.2010.01753.x] [Citation(s) in RCA: 259] [Impact Index Per Article: 19.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Affiliation(s)
- Dana M. Hawley
- Department of Biology, Virginia Tech, Blacksburg, Virginia 24061, USA
| | - Sonia M. Altizer
- Odum School of Ecology, University of Georgia, Athens, Georgia 30602, USA
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Modjarrad K, Vermund SH. Effect of treating co-infections on HIV-1 viral load: a systematic review. THE LANCET. INFECTIOUS DISEASES 2010; 10:455-63. [PMID: 20610327 DOI: 10.1016/s1473-3099(10)70093-1] [Citation(s) in RCA: 136] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Co-infections contribute to HIV-related pathogenesis and often increase viral load in HIV-infected people. We did a systematic review to assess the effect of treating key co-infections on plasma HIV-1-RNA concentrations in low-income countries. We identified 18 eligible studies for review: two on tuberculosis, two on malaria, six on helminths, and eight on sexually transmitted infections, excluding untreatable or non-pathogenic infections. Standardised mean plasma viral load decreased after the treatment of co-infecting pathogens in all 18 studies. The standardised mean HIV viral-load difference ranged from -0.04 log(10) copies per mL (95% CI -0.24 to 0.16) after syphilis treatment to -3.47 log(10) copies per mL (95% CI -3.78 to -3.16) after tuberculosis treatment. Of 14 studies with variance data available, 12 reported significant HIV viral-load differences before and after treatment. Although many of the viral-load reductions were 1.0 log(10) copies per mL or less, even small changes in plasma HIV-RNA concentrations have been shown to slow HIV progression and could translate into population-level benefits in lowering HIV transmission risk.
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Affiliation(s)
- Kayvon Modjarrad
- Department of Medicine, Vanderbilt University School of Medicine, Medical Center, 2525 West End Avenue, Nashville, TN, USA.
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Cassol E, Cassetta L, Alfano M, Poli G. Macrophage polarization and HIV-1 infection. J Leukoc Biol 2009; 87:599-608. [PMID: 20042468 DOI: 10.1189/jlb.1009673] [Citation(s) in RCA: 120] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Affiliation(s)
- Edana Cassol
- AIDS Immunopathogenesis Unit, Division of Immunology, Transplantation and Infectious Diseases, San Raffaele Scientific Institute, Milan, Italy
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Walson JL, Herrin BR, John-Stewart G. Deworming helminth co-infected individuals for delaying HIV disease progression. Cochrane Database Syst Rev 2009:CD006419. [PMID: 19588389 PMCID: PMC2871762 DOI: 10.1002/14651858.cd006419.pub3] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
BACKGROUND The HIV-1 pandemic has disproportionately affected individuals in resource-constrained settings where other infectious diseases, such as helminth infections, also are highly prevalent. There are biologically plausible reasons for possible effects of helminth infection in HIV-1-infected individuals, and findings from multiple studies suggest that helminth infection may adversely affect HIV-1 progression. Since initial publication of this review (Walson 2007), additional data from randomized controlled trials (RCTs) has become available. We sought to evaluate all currently available evidence to determine if treatment of helminth infection in HIV-1 co-infected individuals impacts HIV-1 progression. OBJECTIVES To determine if treating helminth infection in individuals with HIV-1 can reduce the progression of HIV-1 as determined by changes in CD4 count, viral load, or clinical disease progression. SEARCH STRATEGY In this 2008 update, we searched online for published and unpublished studies in The Cochrane Library, MEDLINE, EMBASE, CENTRAL, and AIDSEARCH. We also searched databases listing conference abstracts, scanned reference lists of articles, and contacted authors of included studies. SELECTION CRITERIA We searched for RCTs and quasi-RCTs that compared HIV-1 progression as measured by changes in CD4 count, viral load, or clinical disease progression in HIV-1 infected individuals receiving anti-helminthic therapy. DATA COLLECTION AND ANALYSIS Data regarding changes in CD4 count, HIV-1 RNA levels, and/or clinical staging after treatment of helminth co-infection were extracted from identified studies. MAIN RESULTS Of 7,019 abstracts identified (6,384 from original searches plus 635 from updated searches), 17 abstracts were identified as meeting criteria for potential inclusion (15 from previous review plus an additional two RCTs). After restricting inclusion to RCTs, a total of three studies were eligible for inclusion in this updated review.All three trials showed individual beneficial effects of helminth eradication on markers of HIV-1 disease progression (HIV-1 RNA and/or CD4 counts). When data from these trials were pooled, the analysis demonstrated significant benefit of deworming on both plasma HIV-1 RNA and CD4 counts. AUTHORS' CONCLUSIONS To date, three RCTs have evaluated the effects of deworming on markers of HIV-1 disease progression in helminth and HIV-1 co-infected individuals. All trials demonstrate benefit in attenuating or reducing plasma viral load and/or increasing CD4 counts. When taken together, there is evidence of benefit for deworming HIV-1 co-infected adults. Given that these studies evaluated different helminth species and different interventions, further trials are warranted to evaluate species-specific effects and to document long-term clinical outcomes following deworming.
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Affiliation(s)
- Judd L Walson
- Departments of Global Health, Medicine (Infectious Disease), and Pediatrics, University of Washington, Seattle, WA, USA
| | - Bradley R Herrin
- School of Medicine, University of Washington, Seattle, Washington, USA
| | - Grace John-Stewart
- Allergy and Infectious Diseases, University of Washington, Seattle, Washington, USA
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Woodburn PW, Muhangi L, Hillier S, Ndibazza J, Namujju PB, Kizza M, Ameke C, Omoding NE, Booth M, Elliott AM. Risk factors for helminth, malaria, and HIV infection in pregnancy in Entebbe, Uganda. PLoS Negl Trop Dis 2009; 3:e473. [PMID: 19564904 PMCID: PMC2696595 DOI: 10.1371/journal.pntd.0000473] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2008] [Accepted: 06/01/2009] [Indexed: 01/31/2023] Open
Abstract
Background Infections during pregnancy may have serious consequences for both mother and baby. Assessment of risk factors for infections informs planning of interventions and analysis of the impact of infections on health outcomes. Objectives To describe risk factors for helminths, malaria and HIV in pregnant Ugandan women before intervention in a trial of de-worming in pregnancy. Methods The trial recruited 2,507 pregnant women between April 2003 and November 2005. Participants were interviewed and blood and stool samples obtained; location of residence at enrolment was mapped. Demographic, socioeconomic, behavioral and other risk factors were modelled using logistic regression. Results There was a high prevalence of helminth, malaria and HIV infection, as previously reported. All helminths and malaria parasitemia were more common in younger women, and education was protective against every infection. Place of birth and/or tribe affected all helminths in a pattern consistent with the geographical distribution of helminth infections in Uganda. Four different geohelminths (hookworm, Trichuris, Ascaris and Trichostrongylus) showed a downwards trend in prevalence during the enrolment period. There was a negative association between hookworm and HIV, and between hookworm and low CD4 count among HIV-positive women. Locally, high prevalence of schistosomiasis and HIV occurred in lakeshore communities. Conclusions Interventions for helminths, malaria and HIV need to target young women both in and out of school. Antenatal interventions for malaria and HIV infection must continue to be promoted. Women originating from a high risk area for a helminth infection remain at high risk after migration to a lower-risk area, and vice versa, but overall, geohelminths seem to be becoming less common in this population. High risk populations, such as fishing communities, require directed effort against schistosomiasis and HIV infection. Infections in pregnancy can cause miscarriage, stillbirth, maternal mortality, and low birth weight and have other long-term complications for mother and baby, although the full impact of many infections, particularly worm infections, is not yet fully understood. There is a high burden of infectious disease in many developing countries. In this analysis, we identified which factors put pregnant women in Entebbe, Uganda, at particular risk for worm infections, malaria, HIV, and, where possible, rarer infections including syphilis. The women in this study, and their children, will be followed up to determine the long-term effects of exposure of the fetus to these maternal infections on health during childhood. The findings of this baseline analysis will help in the interpretation of the long-term outcomes. The findings also highlight which groups are most at risk of each infection, and this may help in targeting interventions to prevent, treat, or mitigate the impact of infections in pregnancy.
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Impact of small reductions in plasma HIV RNA levels on the risk of heterosexual transmission and disease progression. AIDS 2008; 22:2179-85. [PMID: 18832881 DOI: 10.1097/qad.0b013e328312c756] [Citation(s) in RCA: 95] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
OBJECTIVE To estimate the impact of small changes in plasma levels of HIV-1 RNA on the risk of heterosexual transmission or disease progression to an AIDS-defining event or death. DESIGN AND METHODS We systematically reviewed the published literature for studies that evaluated small viral load changes among antiretroviral-therapy-naive, adult populations. We modeled relative risk estimates for viral transmission and disease progression according to 0.3, 0.5, and 1.0 log10 increments of HIV load. RESULTS We calculated that the likelihood of transmitting HIV by heterosexual contact increased, on average, by 20% and that the annual risk of progression to an AIDS-defining illness or related death increased by 25% with every 0.3 log10 increment in HIV RNA. A 0.5 log10 increment in HIV RNA was associated with 40% greater risk of heterosexual transmission and 44% increased risk of progression to AIDS or death. A 1.0 log10 increment in HIV RNA was associated with 100% greater risk of heterosexual transmission and 113% increased risk of progression to AIDS or death. CONCLUSION Antiretroviral therapy continues to be unavailable or not-yet-indicated for 72% of the world's HIV-infected persons. Mounting evidence that treatment of coinfections may reduce HIV viral load, even modestly, suggests the priority of improved adjunctive care for HIV-infected persons even without antiretroviral therapy, both to slow disease progression and to reduce infectiousness.
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Talaat KR, Kumarasamy N, Swaminathan S, Gopinath R, Nutman TB. Filarial/human immunodeficiency virus coinfection in urban southern India. Am J Trop Med Hyg 2008; 79:558-560. [PMID: 18840744 PMCID: PMC2596056] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/26/2023] Open
Abstract
The disease course of human immunodeficiency virus (HIV) is often altered by existing or newly acquired coinfections. Treatment or prevention of these concomitant infections often improves the quality and duration of life of HIV-infected persons. The impact of helminth infections on infections with HIV is less clear. However, HIV is frequently most problematic in areas where helminth infections are common. In advance of the widespread distribution of drugs for elimination of lymphatic filariasis, we assessed the prevalence of active Wuchereria bancrofti infection among HIV-positive patients in Chennai, India at two time points separated by four years. We found that the overall prevalence of W. bancrofti infections among HIV-positive persons was 5-9.5%, and there were no quantitative differences in circulating filarial antigen levels between HIV-positive and HIV-negative filarial-infected patients.
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Affiliation(s)
- Kawsar R Talaat
- Laboratory of Parasitic Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland 20892, USA.
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Albendazole treatment of HIV-1 and helminth co-infection: a randomized, double-blind, placebo-controlled trial. AIDS 2008; 22:1601-9. [PMID: 18670219 DOI: 10.1097/qad.0b013e32830a502e] [Citation(s) in RCA: 85] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
OBJECTIVE Several co-infections have been shown to impact the progression of HIV-1 infection. We sought to determine if treatment of helminth co-infection in HIV-1-infected adults impacted markers of HIV-1 disease progression. DESIGN To date, there have been no randomized trials to examine the effects of soil-transmitted helminth eradication on markers of HIV-1 progression. METHODS A randomized, double-blind, placebo-controlled trial of albendazole (400 mg daily for 3 days) in antiretroviral-naive HIV-1-infected adults (CD4 cell count >200 cells/microl) with soil-transmitted helminth infection was conducted at 10 sites in Kenya (ClinicalTrials.gov NCT00130910). CD4 and plasma HIV-1 RNA levels at 12 weeks following randomization were compared in the trial arms using linear regression, adjusting for baseline values. RESULTS Of 1551 HIV-1-infected individuals screened for helminth infection, 299 were helminth infected. Two hundred and thirty-four adults were enrolled and underwent randomization and 208 individuals were included in intent-to-treat analyses. Mean CD4 cell count was 557 cells/microl and mean plasma viral load was 4.75 log10 copies/ml at enrollment. Albendazole therapy resulted in significantly higher CD4 cell counts among individuals with Ascaris lumbricoides infection after 12 weeks of follow-up (+109 cells/microl; 95% confidence interval +38.9 to +179.0, P = 0.003) and a trend for 0.54 log10 lower HIV-1 RNA levels (P = 0.09). These effects were not seen with treatment of other species of soil-transmitted helminths. CONCLUSION Treatment of A. lumbricoides with albendazole in HIV-1-coinfected adults resulted in significantly increased CD4 cell counts during 3-month follow-up. Given the high prevalence of A. lumbricoides infection worldwide, deworming may be an important potential strategy to delay HIV-1 progression.
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Borkow G, Bentwich Z. Chronic parasite infections cause immune changes that could affect successful vaccination. Trends Parasitol 2008; 24:243-5. [DOI: 10.1016/j.pt.2008.02.009] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2007] [Revised: 02/25/2008] [Accepted: 02/25/2008] [Indexed: 10/22/2022]
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Walson JL, John-Stewart G. Treatment of helminth co-infection in HIV-1 infected individuals in resource-limited settings. Cochrane Database Syst Rev 2008:CD006419. [PMID: 18254104 PMCID: PMC3372409 DOI: 10.1002/14651858.cd006419.pub2] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
BACKGROUND The HIV-1 pandemic has disproportionately affected individuals in resource-constrained settings. These areas often also have high prevalence of other infectious diseases, such as helminth infections. It is important to determine if helminth infection affects the progression of HIV-1 in these co-infected individuals. There are biologically plausible reasons for possible effects of helminth infection in HIV-1 infected individuals and findings from some observational studies suggest that helminth infection may adversely affect HIV-1 progression. We sought to evaluate the available evidence from published and unpublished studies to determine if treatment of helminth infection in HIV-1 co-infected individuals impacts HIV-1 progression. OBJECTIVES Our objective was to determine if treating helminth infection in individuals with HIV-1 can reduce the progression of HIV-1 as determined by changes in CD4 count, viral load, or clinical disease progression (including mortality). SEARCH STRATEGY We searched online for published and unpublished studies in The Cochrane Library (Issue 3, 2006), MEDLINE (November 2006), EMBASE (November 2006), CENTRAL (July 2006), AIDSEARCH (August 2006). We also searched databases listing conference abstracts, scanned reference lists of articles, and contacted authors of included studies. SELECTION CRITERIA We searched for randomized and quasi-randomized controlled trials that compared HIV-1 progression as measured by changes in CD4 count, viral load, or clinical disease progression in HIV-1 infected individuals receiving anti-helminth therapy. Observational studies with relevant data were also included. DATA COLLECTION AND ANALYSIS Data regarding changes in CD4 count, HIV-1 RNA levels, clinical staging and/or mortality after treatment of helminth co-infection were extracted from the reports of the studies. MAIN RESULTS Of 6,384 abstracts identified, 15 met criteria for potential inclusion, of which five were eligible for inclusion. In the single randomized controlled trial (RCT) identified, HIV-1 and schistosomiasis co-infected individuals receiving treatment for schistosomiasis had a significantly lower change in plasma HIV-1 RNA over three months (-0.001 log10 copies/mL) compared to those receiving no treatment (+0.21 log10 copies/mL), (p=0.03). Four observational studies met inclusion criteria and all of these suggested a possible beneficial effect of helminth eradication on plasma HIV-1 RNA levels when compared to plasma HIV-1 RNA changes prior to helminth treatment or to helminth-uninfected or persistently helminth-infected individuals. Follow-up duration in these studies ranged from three to six months. The reported magnitude of effect on HIV-1 RNA was variable, ranging from 0.07-1.05 log10 copies/mL. None of the included studies showed a significant benefit of helminth treatment on CD4 decline, clinical staging, or mortality. AUTHORS' CONCLUSIONS There are insufficient data available to determine the potential benefit of helminth eradication in HIV-1 and helminth co-infected adults. Data from a single RCT and multiple observational studies suggest possible benefit in reducing plasma viral load. The impact of de-worming on markers of HIV-1 progression should be addressed in larger randomized studies evaluating species-specific effects and with a sufficient duration of follow-up to document potential differences on clinical outcomes and CD4 decline.
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Affiliation(s)
- J L Walson
- University of Washington, Allergy and Infectious Diseases, Box 359909, University of Washington, 325 Ninth Avenue, Seattle, WA 98104, USA.
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Walson JL, John-Stewart G. Treatment of helminth co-infection in individuals with HIV-1: A systematic review of the literature. PLoS Negl Trop Dis 2007; 1:e102. [PMID: 18160978 PMCID: PMC2154389 DOI: 10.1371/journal.pntd.0000102] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2007] [Accepted: 09/11/2007] [Indexed: 11/18/2022] Open
Abstract
Background and Objectives The HIV-1 pandemic has disproportionately affected individuals in resource-constrained settings. It is important to determine if other prevalent infections affect the progression of HIV-1 in co-infected individuals in these settings. Some observational studies suggest that helminth infection may adversely affect HIV-1 progression. We sought to evaluate existing evidence on whether treatment of helminth infection impacts HIV-1 progression. Review Methods This review was conducted using the HIV/AIDS Cochrane Review Group (CRG) search strategy and guidelines. Published and unpublished studies were obtained from The Cochrane Library (Issue 3, 2006), MEDLINE (November 2006), EMBASE (November 2006), CENTRAL (July 2006), and AIDSEARCH (August 2006). Databases listing conference abstracts and scanned reference lists were searched, and authors of included studies were contacted. Data regarding changes in CD4 count, HIV-1 RNA levels, clinical staging and/or mortality were extracted and compared between helminth-treated and helminth-untreated or helminth-uninfected individuals. Results Of 6,384 abstracts identified, 15 met criteria for potential inclusion, of which 5 were eligible for inclusion. In the single randomized controlled trial (RCT) identified, HIV-1 and schistosomiasis co-infected individuals receiving treatment for schistosomiasis had a significantly lower change in plasma HIV-1 RNA over three months (−0.001 log10 copies/mL) compared to those receiving no treatment (+0.21 log10 copies/mL), (p = 0.03). Four observational studies met inclusion criteria, and all of these suggested a possible beneficial effect of helminth eradication on plasma HIV-1 RNA levels when compared to plasma HIV-1 RNA changes prior to helminth treatment or to helminth-uninfected or persistently helminth-infected individuals. The follow-up duration in these studies ranged from three to six months. The reported magnitude of effect on HIV-1 RNA was variable, ranging from 0.07–1.05 log10 copies/mL. None of the included studies showed a significant benefit of helminth treatment on CD4 decline, clinical staging, or mortality. Conclusion There are insufficient data available to determine the potential benefit of helminth eradication in HIV-1 and helminth co-infected adults. Data from a single RCT and multiple observational studies suggest possible benefit in reducing plasma viral load. The impact of de-worming on markers of HIV-1 progression should be addressed in larger randomized studies evaluating species-specific effects and with a sufficient duration of follow-up to document potential differences on clinical outcomes and CD4 decline. Many people living in areas of the world most affected by the HIV/AIDS pandemic are also exposed to other common infections. Parasitic infections with helminths (intestinal worms) are common in Africa and affect over half of the population in some areas. There are plausible biological reasons why treating helminth infections in people with HIV may slow down the progression of HIV to AIDS. Thus, treating people with HIV for helminths in areas with a high prevalence of both HIV and helminth infections may be a feasible strategy to help people with HIV delay progression of their disease or initiation of antiretroviral therapy. After a comprehensive review of the available literature, we conclude that there is not enough evidence to determine whether treating helminth infections in people with HIV is beneficial.
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Affiliation(s)
- Judd L Walson
- Department of Medicine, University of Washington, Seattle, Washington, USA.
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Fauci AS. Pathogenesis of HIV Disease: Opportunities for New Prevention Interventions. Clin Infect Dis 2007; 45 Suppl 4:S206-12. [DOI: 10.1086/522540] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
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Secor WE, Sundstrom JB. Below the belt: new insights into potential complications of HIV-1/schistosome coinfections. Curr Opin Infect Dis 2007; 20:519-23. [PMID: 17762787 DOI: 10.1097/qco.0b013e3282e9ac03] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
PURPOSE OF REVIEW Areas of the world with high endemnicity for helminth parasites overlap with those regions that have a seemingly disproportionate prevalence of HIV/AIDS. This has fueled speculation that potential pathological interactions between these infectious agents may accelerate disease progression. The proximity of many helminth infections to gastrointestinal mucosal sites combined with the recent discovery that acute HIV-1 infection causes early and massive depletion of CD4+ T cells in the gut furthers the potential pathological significance of co-infection. In this review, the 'gut wrenching' consequences of schistosome infection on HIV disease progression that may ensue during coinfection are considered. RECENT FINDINGS Massive depletion of CD4+ T cells in the gut during acute HIV-1 infection suggests that in addition to the administration of highly active antiretroviral therapy, limiting viral infection of susceptible cells in the gut after initial exposure may offer the best opportunity for slowing disease progression. In addition to memory T cells, mast cells, which are present in the intestinal lamina propria and upregulated in the gut during schistosome infection, have been recently described as an inducible reservoir of persistent HIV-1 infection. SUMMARY Schistosome infections create immune environments that may accelerate HIV disease progression. Their impact on highly active antiretroviral therapy should be considered.
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Affiliation(s)
- W Evan Secor
- Division of Parasitic Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia 30341-3724, USA.
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Mayer KH, Karp CL, Auwaerter PG, Mayer KH. Coinfection with HIV and Tropical Infectious Diseases. II. Helminthic, Fungal, Bacterial, and Viral Pathogens. Clin Infect Dis 2007; 45:1214-20. [DOI: 10.1086/522180] [Citation(s) in RCA: 66] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2007] [Accepted: 07/07/2007] [Indexed: 01/19/2023] Open
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Elias D, Britton S, Kassu A, Akuffo H. Chronic helminth infections may negatively influence immunity against tuberculosis and other diseases of public health importance. Expert Rev Anti Infect Ther 2007; 5:475-84. [PMID: 17547511 DOI: 10.1586/14787210.5.3.475] [Citation(s) in RCA: 65] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Tuberculosis (TB) has once again become a major public health threat owing to the combined effects of deteriorating socioeconomic situations and the emergence of the HIV/AIDS pandemic. The only vaccine available against TB, although effective in reducing the burden of childhood TB, shows enormous variability in its efficacy against pulmonary TB, which is the most common form of the disease in adults. Most areas of high TB incidence and poor TB vaccine efficacy have a high prevalence of intestinal helminth infections. Such infections have been shown to cause a range of immunomodulation characterized by enhanced T helper 2-type cytokine profile, high immunoglobulin E levels and upregulated regulatory T-cell activity, as well as chronic immune activation. An altered background immune profile could have adverse effects on the outcome of subsequent infections and vaccinations. In support of this hypothesis, studies conducted in animals and humans living in worm-endemic areas have shown that helminths impair resistance against a number of infections of major public health importance, including TB, malaria and HIV/AIDS. Understanding such interactions could assist in the design of vaccines against these diseases.
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Affiliation(s)
- Daniel Elias
- ACE Biosciences, Unsbjergvej 2A, 5220 Odense SOE, Denmark.
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van Riet E, Hartgers FC, Yazdanbakhsh M. Chronic helminth infections induce immunomodulation: consequences and mechanisms. Immunobiology 2007; 212:475-90. [PMID: 17544832 DOI: 10.1016/j.imbio.2007.03.009] [Citation(s) in RCA: 265] [Impact Index Per Article: 15.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2007] [Accepted: 03/01/2007] [Indexed: 12/19/2022]
Abstract
Worldwide, more than a billion people are infected with helminths. These worm infections generally do not lead to mortality, however, they are chronic in nature and can lead to considerable morbidity. Immunologically these infections are interesting; chronic helminth infections are characterized by skewing towards a T helper 2 type response as well as regulatory responses. The regulatory network is associated with chronic helminth infections and is thought to prevent strong immune responses against parasitic worms, allowing their long-term survival and restricting pathology. This regulatory network is thought to also temper responses to non-helminth antigens, like allergens or self-antigens, possibly leading to lower prevalence of allergies and autoimmune diseases in subjects that are chronically infected with helminths. This raises the interesting idea that helminths may bear molecules that have potential therapeutic action against allergies and possibly other inflammatory diseases. However, on the other side of the coin, this would predict that helminth infected subjects might not respond strongly to third party antigens like vaccines. This is an important issue, since most vaccines that are being developed against diseases such as HIV, tuberculosis or malaria will be introduced in areas where helminth infections are highly prevalent. Moreover, these vaccines are proving difficult to develop and are often weak, thus any confounder that would affect their efficacy needs to be taken into consideration. Helminth derived molecules have been identified that induce T helper 2 and regulatory responses via modulation of dendritic cells and some appear to do so via Toll like receptor (TLR) signaling. New insights into these pathways could be useful to antagonize suppression and hence boost vaccine efficacy or to optimize suppression induced by helminth derived molecules and control inflammatory diseases.
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Affiliation(s)
- Elly van Riet
- Department of Parasitology, Leiden University Medical Centre, Leiden, The Netherlands.
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Ayash-Rashkovsky M, Chenine AL, Steele LN, Lee SJ, Song R, Ong H, Rasmussen RA, Hofmann-Lehmann R, Else JG, Augostini P, McClure HM, Secor WE, Ruprecht RM. Coinfection with Schistosoma mansoni reactivates viremia in rhesus macaques with chronic simian-human immunodeficiency virus clade C infection. Infect Immun 2007; 75:1751-6. [PMID: 17283092 PMCID: PMC1865689 DOI: 10.1128/iai.01703-06] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
We tested the hypothesis that helminth parasite coinfection would intensify viremia and accelerate disease progression in monkeys chronically infected with an R5 simian-human immunodeficiency virus (SHIV) encoding a human immunodeficiency virus type 1 (HIV-1) clade C envelope. Fifteen rhesus monkeys with stable SHIV-1157ip infection were enrolled into a prospective, randomized trial. These seropositive animals had undetectable viral RNA and no signs of immunodeficiency. Seven animals served as virus-only controls; eight animals were exposed to Schistosoma mansoni cercariae. From week 5 after parasite exposure onward, coinfected animals shed eggs in their feces, developed eosinophilia, and had significantly higher mRNA expression of the T-helper type 2 cytokine interleukin-4 (P = 0.001) than animals without schistosomiasis. Compared to virus-only controls, viral replication was significantly increased in coinfected monkeys (P = 0.012), and the percentage of their CD4(+) CD29(+) memory cells decreased over time (P = 0.05). Thus, S. mansoni coinfection significantly increased viral replication and induced T-cell subset alterations in monkeys with chronic SHIV clade C infection.
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Abstract
This paper discusses the most important parasites that inhabit the human small intestine. Beginning with the protozoa and proceeding through the various species of cestodes, nematodes, and trematodes that inhabit the human small bowel, the most important organisms are presented. Possible future developments are discussed along with pathophysiology and treatment in this phylogenic approach. Zoonotic illnesses, those diseases that by their rarity are of little import, and diseases without significant clinical or social implications are beyond the scope of this article and are not discussed.
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Affiliation(s)
- Theodore W Schafer
- Division of Gastroenterology, Naval Medical Center, 620 John Paul Jones Cir., Portsmouth, VA 23708, USA.
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Abstract
In many regions of the world, both schistosomiasis and HIV/AIDS are endemic, resulting in patients harbouring co-infections. Because interaction with host CD4(+) T cells is a characteristic of schistosome as well as HIV-1 infections, bi-directional disease effects may be sufficiently different from sequelae caused by either infectious agent alone to warrant alteration of public health approaches in areas of co-endemnicity. Studies published over the past decade provide useful insights into interactions between schistosomiasis and infection with HIV-1, and overall support the hypothesis that special emphasis on treatment of schistosomiasis in populations with elevated prevalence or risk of HIV-1 infection is justified.
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Affiliation(s)
- W E Secor
- Division of Parasitic Diseases, Centers for Disease Control and Prevention, Public Health Service, Department of Health and Human Services, Atlanta, Georgia, USA.
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Abstract
We have previously suggested that helminth infections play a major role in the pathogenesis of HIV-1 infection in Africa and other developing areas, due to their profound effects on the host immune system, which make those infected more susceptible to HIV-1 infection and less able to cope with it. Chronic immune activation with a dominant Th2 profile, and anergy, are the hallmarks of chronic helminth infection, and may therefore account for most of these effects. In the present review, we summarize the studies that have addressed these issues and argue that despite some conflicting results, the cumulative immunological and epidemiological evidence is in favour of deworming as a preventive and possible therapeutic measure vis-à-vis HIV-1 infection. We suggest that it should be at least tested on a wider and larger scale than has been done until now, because of its immense potential impact on the still raging AIDS epidemic in developing countries.
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Affiliation(s)
- G Borkow
- Cupron Inc., Beth-Shemesh, Israel
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