Huw V Smith

University of Melbourne, Melbourne, Victoria, Australia

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Publications (23)74.17 Total impact

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    ABSTRACT: Continuous exposure to low levels of Cryptosporidium oocysts is associated with production of protective antibodies. We investigated prevalence of antibodies against the 27-kDa Cryptosporidium oocyst antigen among blood donors in 2 areas of Scotland supplied by drinking water from different sources with different filtration standards: Glasgow (not filtered) and Dundee (filtered). During 2006-2009, seroprevalence and risk factor data were collected; this period includes 2007, when enhanced filtration was introduced to the Glasgow supply. A serologic response to the 27-kDa antigen was found for ≈75% of donors in the 2 cohorts combined. Mixed regression modeling indicated a 32% step-change reduction in seroprevalence of antibodies against Cryptosporidium among persons in the Glasgow area, which was associated with introduction of enhanced filtration treatment. Removal of Cryptosporidium oocysts from water reduces the risk for waterborne exposure, sporadic infections, and outbreaks. Paradoxically, however, oocyst removal might lower immunity and increase the risk for infection from other sources.
    Emerging Infectious Diseases 01/2014; 20(1):71-8. · 6.79 Impact Factor
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    ABSTRACT: Given the HIV epidemic in Malaysia, genetic information on opportunistic pathogens, such as Cryptosporidium and Giardia, in HIV/AIDS patients is pivotal to enhance our understanding of epidemiology, patient care, management and disease surveillance. In the present study, 122 faecal samples from HIV/AIDS patients were examined for the presence of Cryptosporidium oocysts and Giardia cysts using a conventional coproscopic approach. Such oocysts and cysts were detected in 22.1% and 5.7% of the 122 faecal samples, respectively. Genomic DNAs from selected samples were tested in a nested-PCR, targeting regions of the small subunit (SSU) of nuclear ribosomal RNA and the 60kDa glycoprotein (gp60) genes (for Cryptosporidium), and the triose-phosphate isomerase (tpi) gene (for Giardia), followed by direct sequencing. The sequencing of amplicons derived from SSU revealed that Cryptosporidium parvum was the most frequently detected species (64% of 25 samples tested), followed by C. hominis (24%), C. meleagridis (8%) and C. felis (4%). Sequencing of a region of gp60 identified C. parvum subgenotype IIdA15G2R1 and C. hominis subgenotypes IaA14R1, IbA10G2R2, IdA15R2, IeA11G2T3R1 and IfA11G1R2. Sequencing of amplicons derived from tpi revealed G. duodenalis assemblage A, which is of zoonotic importance. This is the first report of C. hominis, C. meleagridis and C. felis from Malaysian HIV/AIDS patients. Future work should focus on an extensive analysis of Cryptosporidium and Giardia in such patients as well as in domestic and wild animals, in order to improve the understanding of transmission patterns and dynamics in Malaysia. It would also be particularly interesting to establish the relationship among clinical manifestation, CD4 cell counts and genotypes/subgenotypes of Cryptosporidium and Giardia in HIV/AIDS patients. Such insights would assist in a better management of clinical disease in immuno-deficient patients as well as improved preventive and control strategies.
    Infection, genetics and evolution: journal of molecular epidemiology and evolutionary genetics in infectious diseases 03/2011; 11(5):968-74. · 3.22 Impact Factor
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    ABSTRACT: Cryptosporidium is an important genus of parasitic protozoa of humans and other vertebrates and is a major cause of intestinal disease globally. Unlike many common causes of infectious enteritis, there are no widely available, effective vaccine or drug-based intervention strategies for Cryptosporidium, and control is focused mainly on prevention. This approach is particularly deficient for infections of severely immunocompromised and/or suppressed, the elderly or malnourished people. However, cryptosporidiosis also presents a significant burden on immunocompetent individuals, and can, for example have lasting effects on the physical and mental development of children infected at an early age. In the last few decades, our understanding of Cryptosporidium has expanded significantly in numerous areas, including the parasite life-cycle, the processes of excystation, cellular invasion and reproduction, and the interplay between parasite and host. Nonetheless, despite extensive research, many aspects of the biology of Cryptosporidium remain unknown, and treatment and control are challenging. Here, we review the current state of knowledge of Cryptosporidium, with a focus on major advances arising from the recently completed genome sequences of the two species of greatest relevance in humans, namely Cryptosporidium hominis and Cryptosporidium parvum. In addition, we discuss the potential of next-generation sequencing technologies, new advances in in silico analyses and progress in in vitro culturing systems to bridge these gaps and to lead toward effective treatment and control of cryptosporidiosis.
    Advances in Parasitology 01/2011; 77:141-73. · 3.78 Impact Factor
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    ABSTRACT: A longitudinal study was conducted to determine the epidemiology of Cryptosporidium in 1,636 children in Nigeria. Oocyst prevalence ranged from 15.6% to 19.6% over one year. Cryptosporidium hominis (34), C. parvum (25), C. parvum/C. hominis (4), C. meleagridis (5), Cryptosporidium rabbit genotype (5), Cryptosporidium cervine genotype (3), and C. canis (1) were identified by polymerase chain reaction-restriction fragment length polymorphism analysis. Glycoprotein 60 subgenotyping showed that 28 amplifiable C. hominis isolates consisted of 12 subtypes that belonged to 5 subtype families (Ia, Ib, Id, Ie, and 1 novel subtype family, Ih) and 23 amplifiable C. parvum isolates consisted of 6 subtypes that belonged to 4 subtype families (IIa, IIc, Iii, and IIm). Three C. meleagridis isolates sub-genotyped by sequence analysis of the small subunit ribosomal RNA gene fragment were type 1. This study is the first one to genetically characterize Cryptosporidium species and subtypes in Nigeria and highlights the presence of a high Cryptosporidium diversity in this pediatric population.
    The American journal of tropical medicine and hygiene 04/2010; 82(4):608-13. · 2.53 Impact Factor
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    ABSTRACT: Cryptosporidiosis is a socioeconomically important, enteric disease caused by a group of protozoan parasites of the genus Cryptosporidium. The significant morbidity and mortality in animals and humans caused by this disease as well as its considerable impact on the water industry have made its prevention and control a global challenge, particularly given that there are presently no widespread, affordable or effective treatment or vaccination strategies. Although much is known about Cryptosporidium and the impact of cryptosporidiosis and other diarrhoeal diseases in developed countries, this is not the case for many developing countries in Africa, South America and Asia. In Southeast Asia, which represents an epicentre for emerging infectious diseases, cryptosporidiosis has been reported in countries, such as Cambodia, Indonesia, Laos, Malaysia, Myanmar, the Philippines, Singapore, Thailand and Vietnam. In most of these countries, the likely predisposing factors for cryptosporidiosis include rapid population growth and expanding urbanisation (which are often linked to inadequate municipal water supplies and poorly managed refuse disposal) as well as the tropical climate and the increasing prevalence of HIV/AIDS and other infectious diseases. Given the close proximity of these countries and the extent of migration within and among them, cryptosporidiosis can be difficult to control. National and regional surveillance is central to preventing and controlling cryptosporidiosis. To date, most studies of cryptosporidiosis in Southeast Asia have focus on estimating the prevalence of infection in humans and animals using conventional diagnostic techniques. Future investigations using reliable molecular tools should enable improved insights into the epidemiology, systematics and population genetics of Cryptosporidium in this region. An enhanced understanding of the transmission of cryptosporidial infections and the significance of environmental contamination will require a multidisciplinary approach, built on shared resources. Such an integrated approach would underpin stable and powerful partnerships in efforts to prevent and control this disease. The purpose of the present chapter is to review available data and information on cryptosporidiosis in Southeast Asia and to provide recommendations in the pursuit of a better understanding of Cryptosporidium in this region, in order to facilitate the development of effective multidisciplinary interventions to control cryptosporidiosis.
    Advances in Parasitology - ADVAN PARASITOL. 01/2010; 71:1-31.
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    ABSTRACT: Nine 50-l surface water samples from a Malaysian recreational lake were examined microscopically using an immunomagnetisable separation–immunofluorescent method. No Cryptosporidium oocysts were detected, but 77.8% of samples contained low numbers of Giardia cysts (range, 0.17–1.1 cysts/l), which were genetically characterised by SSU rRNA gene sequencing. Genotype analyses indicated the presence of Giardia duodenalis assemblage A suggesting potential risk to public health. The present study represents the first contribution to our knowledge of G. duodenalis assemblages in Malaysian recreational water.
    Parasitology Research 12/2009; 106(1):289-291. · 2.85 Impact Factor
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    ABSTRACT: The ubiquity and importance of Giardia and Cryptosporidium as pathogens are reflected in the increasing number of publications concerning these organisms, but they are not the only reason why researchers are increasingly turning their attention to studying Giardia and Cryptosporidium. As new tools and databases become available, it is now possible to investigate fundamental issues related to their biology and relationship with their hosts. In this article, we highlight recent advances in research and outline questions arising that need to be addressed as a way of focusing the attention of the research and health communities and encouraging further dialogue and collaboration.
    Trends in Parasitology 10/2009; 25(9):410-6. · 5.51 Impact Factor
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    ABSTRACT: We used a combined microscopy-molecular approach to determine the occurrence and identities of waterborne Giardia sp. cysts isolated from 18 separate, 10l grab samples collected from a Malaysian zoo. Microscopy revealed that 17 of 18 samples were Giardia cyst positive with concentrations ranging from 1 to 120 cysts/l. Nine (52.9%) of the 17 cyst positive samples produced amplicons of which 7 (77.8%) could be sequenced. Giardia duodenalis assemblage A (6 of 7) and assemblage B (1 of 7), both infectious to humans, were identified at all sampling sites at the zoo. The presence of human infectious cysts raises public health issues, and their occurrence, abundance and sources should be investigated further. In this zoo setting, our data highlight the importance of incorporating environmental sampling (monitoring) in addition to routine faecal examinations to determine veterinary and public health risks, and water monitoring should be considered for inclusion as a separate element in hazard analysis, as it often has a historical (accumulative) connotation.
    Environmental Research 09/2009; 109(7):857-9. · 3.24 Impact Factor
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    Huw V Smith, Rosely A B Nichols
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    ABSTRACT: Water and food are major environmental transmission routes for Cryptosporidium, but our ability to identify the spectrum of oocyst contributions in current performance-based methods is limited. Determining risks in water and foodstuffs, and the importance of zoonotic transmission, requires the use of molecular methods, which add value to performance-based morphologic methods. Multi-locus approaches increase the accuracy of identification, as many signatures detected in water originate from species/genotypes that are not infectious to humans. Method optimisation is necessary for detecting small numbers of oocysts in environmental samples consistently, and further work is required to (i) optimise IMS recovery efficiency, (ii) quality assure performance-based methods, (iii) maximise DNA extraction and purification, (iv) adopt standardised and validated loci and primers, (v) determine the species and subspecies range in samples containing mixtures, and standardising storage and transport matrices for validating genetic loci, primer sets and DNA sequences.
    Experimental Parasitology 07/2009; 124(1):61-79. · 2.15 Impact Factor
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    ABSTRACT: We describe an outbreak of cryptosporidiosis in Stone curlews kept in a mixed-species rearing unit in Dubai. Cryptosporidium was the predominant intestinal pathogen detected, although microbiological investigations revealed a concurrent Salmonella infantis infection in two of the 29 Stone curlew chicks that died. Nineteen of 29 birds had catarrhal enteritis associated with histopathological findings of numerous Cryptosporidium developmental stages at the mucosal surface. Catarrhal enteritis was present without associated Cryptosporidium oocysts in five cases. Histology of the intestine, faecal examination by direct microscopy and antigenic detection by immunochromatography revealed the presence of Cryptosporidium spp. associated with catarrhal enteritis in intestinal sections and faeces. Clinical and histopathological outcomes of infection were severe, including disruption of intestinal epithelial integrity, the presence of numerous endogenous Cryptosporidium stages in intestinal epithelia and the excretion of large numbers of sporulated oocysts. The application of polymerase chain reaction and restriction fragment length polymorphism techniques at two 18S rRNA and one Cryptosporidium oocyst wall protein gene locus confirmed the presence of Cryptosporidium parvum DNA in faecal samples.
    Avian Pathology 11/2008; 37(5):521-6. · 1.73 Impact Factor
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    ABSTRACT: We genotyped 297 Scottish C. parvum samples using micro- and minisatellites. Treated as a single population, the population structure was epidemic. When regional populations were analysed, there was evidence of sub-population structure variations. This was dependent upon excluding sub-groups exhibiting significant genetic distance from the main population, implying genetic sub-structuring. We tested the hypothesis that these sub-groups originated outside the UK and demonstrated that one sub-group clustered with Peruvian samples. A geographically comprehensive panel of isolates would fully confirm this result. These data indicate limited sub-structuring within a small geographical area, but substantial sub-structuring over larger geographical distances. Host movement influences parasite diversity and population structure, evidenced by strong correlation (r(2) = 0.9686) between cattle movements and parasite diversity. Thus, the population structure of C. parvum is complex, with sub-populations differing in structure and being influenced by host movements, including the introduction of novel multilocus genotypes from geographically distinct regions.
    Infection Genetics and Evolution 04/2008; 8(2):121-9. · 2.77 Impact Factor
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    ABSTRACT: Previous evidence has suggested an association between consumption of unfiltered water from Loch Lomond, Scotland, and cryptosporidiosis. Before November 1999, this water had been only microstrained and disinfected with chlorine; however, since that time, physical treatment of the water (coagulation, rapid gravity filtration) has been added. To determine risk factors, including drinking water, for cryptosporidiosis, we analyzed data on laboratory-confirmed cases of cryptosporidiosis collected from 1997 through 2003. We identified an association between the incidence of cryptosporidiosis and unfiltered drinking water supplied to the home. The association supports the view that adding a filtration system to minimally treated water can substantially reduce the number of confirmed cryptosporidiosis cases.
    Emerging infectious diseases 02/2008; 14(1):115-20. · 5.99 Impact Factor
  • Huw V. Smith, Rosely A. B. Nichols
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    ABSTRACT: Seven species of the intracellular, protozoan parasite, Cryptosporidium, cause diarrhea in humans. Cryptosporidium completes its life cycle in individual hosts, and its infectious dose is small (ID50 = 9-1042 oocysts). Its virulence and pathogenicity are poorly understood. The drug of choice for immunocompetent individuals is nitazoxanide and modifications of treatment regimens may also increase its usefulness for immunocompromised individuals. Immune reconstitution using highly active antiretroviral therapy and secondary prophylaxis should be considered in HIV-infected individuals. Transmission to humans can occur via any mechanism by which material contaminated with feces containing infectious oocysts from infected human beings or non-human hosts can be swallowed by a susceptible host. Biotic reservoirs include all potential hosts of human-infectious Cryptosporidium species, while abiotic reservoirs include all vehicles that contain sufficient infectious oocysts to cause human infection, the most commonly recognized being food and water. Both foodborne and waterborne outbreaks have been documented. In three out of the six foodborne outbreaks documented, contaminated foodstuffs were implicated as the vehicles of transmission, but in another two, foodhandlers, rather than indigenous contamination of foodstuff, were implicated in disease transmission. Increased global sourcing and rapid transport of soft fruit, salad vegetables, and seafood can enhance both the likelihood of oocyst contamination and oocyst survival. Standardized methods for detecting oocysts on foods must be maximized as there is no method to augment parasite numbers prior to detection. Oocyst contamination of food can be on the surface of, or in, the food matrix and products at greatest risk of transmitting infection include those that receive no, or minimal, heat treatment after they become contaminated. Heating at ≥64.2 for 2 min and exposure to UV light ablates Cryptosporidium parvum infectivity for neonatal mice, while drying/desiccation for 4 h or exposure to 0.03% H2O2 for ≥2 h ablates oocyst viability. Disinfectants and other treatment processes used in the food industry may be detrimental to oocyst survival or lethal, but further research in this important area is required. Both foodborne and waterborne outbreaks have been documented. In three out of the six foodborne outbreaks documented, contaminated foodstuffs were implicated as the vehicles of transmission, but in another two, foodhandlers, rather than indigenous contamination of foodstuff, were implicated in disease transmission. Increased global sourcing and rapid transport of soft fruit, salad vegetables, and seafood can enhance both the likelihood of oocyst contamination and oocyst survival. Standardized methods for detecting oocysts on foods must be maximized as there is no method to augment parasite numbers prior to detection. Oocyst contamination of food can be on the surface of, or in, the food matrix and products at greatest risk of transmitting infection include those that receive no, or minimal, heat treatment after they become contaminated. Heating at ≥64.2 for 2 min and exposure to UV light ablates Cryptosporidium parvum infectivity for neonatal mice, while drying/desiccation for 4 h or exposure to 0.03% H2O2 for ≥2 h ablates oocyst viability. Disinfectants and other treatment processes used in the food industry may be detrimental to oocyst survival or lethal, but further research in this important area is required.
    11/2007: pages 233-276;
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    ABSTRACT: Cryptosporidium parvum and Cryptosporidium hominis isolates from sporadic, drinking water-associated, and intrafamilial human cases together with C. parvum isolates from sporadic cases in livestock were collected in the United Kingdom between 1995 and 1999. The isolates were characterized by analysis of three microsatellite markers (ML1, GP15, and MS5) using PCR amplification. Within C. hominis, four alleles were detected within the GP15 and MS5 loci, and a single type was detected with ML1. C. parvum was more polymorphic; 12 alleles were detected with GP15, 6 were detected with MS5, and 3 were detected with ML1. Multilocus analysis of polymorphisms within the three microsatellite loci was combined with those reported previously for an extrachromosomal small double-stranded RNA. Forty multilocus types were detected within these two species: 9 were detected in C. hominis, and 31 were detected in C. parvum. In C. hominis, heterogeneity was almost exclusively found in samples from sporadic cases. Similarity analysis identified three main groups within C. parvum, and the group that predominated in human infection was also found in livestock. Multilocus types of C. parvum previously identified only in humans were not detected in livestock. Isolates of both C. hominis and C. parvum from separate waterborne outbreaks were genetically homogeneous, suggesting preferential or point source transmission of certain types of these two species of parasites.
    Journal of Clinical Microbiology 11/2007; 45(10):3286-94. · 4.07 Impact Factor
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    ABSTRACT: We developed and validated a PCR-based method for identifying Cryptosporidium species and/or genotypes present on oocyst-positive microscope slides. The method involves removing coverslips and oocysts from previously examined slides followed by DNA extraction. We tested four loci, the 18S rRNA gene (N18SDIAG and N18SXIAO), the Cryptosporidium oocyst wall protein (COWP) gene (STN-COWP), and the dihydrofolate reductase (dhfr) gene (by multiplex allele-specific PCR), for amplifying DNA from low densities of Cryptosporidium parvum oocysts experimentally seeded onto microscope slides. The N18SDIAG locus performed consistently better than the other three tested. Purified oocysts from humans infected with C. felis, C. hominis, and C. parvum and commercially purchased C. muris were used to determine the sensitivities of three loci (N18SDIAG, STN-COWP, and N18SXIAO) to detect low oocyst densities. The N18SDIAG primers provided the greatest number of positive results, followed by the N18SXIAO primers and then the STN-COWP primers. Some oocyst-positive slides failed to generate a PCR product at any of the loci tested, but the limit of sensitivity is not entirely based on oocyst number. Sixteen of 33 environmental water monitoring Cryptosporidium slides tested (oocyst numbers ranging from 1 to 130) contained mixed Cryptosporidium species. The species/genotypes most commonly found were C. muris or C. andersoni, C. hominis or C. parvum, and C. meleagridis or Cryptosporidium sp. cervine, ferret, and mouse genotypes. Oocysts on one slide contained Cryptosporidium muskrat genotype II DNA.
    Applied and Environmental Microbiology 09/2006; 72(8):5428-35. · 3.95 Impact Factor
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    ABSTRACT: We describe a rapid method for extracting and concentrating Cryptosporidium oocysts from human faecal samples with subsequent DNA preparation for mainstream PCR applications. This method consists of extracting faecal lipids using a modified water-ether treatment and releasing DNA from semi-purified oocysts by freeze thawing in lysis buffer. Following immunomagnetisable separation (IMS), recovery rates of 29.5%, 43.2% and 49.8% were obtained from oocyst-negative solid, semi-solid and liquid faeces, respectively, seeded with 100 +/- 2 C. parvum oocysts, which were enumerated by flow cytometry. A retrospective analysis was conducted on 92 positive human faecal samples including 78 oocyst-positive cases from 2 UK cryptosporidiosis outbreaks (outbreak A = 34 samples, outbreak B = 44 samples) and 14 oocyst-positive, sporadic cases. We used primers targeting the Cryptosporidium oocyst wall protein gene (COWP; STN-COWP), the 18S rRNA (direct PCR) and the dihydrofolate reductase gene (dhfr, MAS-PCR) fragments to evaluate extracted DNA by PCR. PCR inhibitors were present in 20 samples when template was co-amplified with the 18S rRNA gene primers and an internal control. Template dilution (1/5) in polyvinylpyrrolidone (10 mg ml(-1), pH 8.0) transformed four PCR-negative samples to PCR-positive and increased amplicon intensity in previously positive samples. Eighteen of 20 PCR-negative samples produced visible amplicons when Taq polymerase concentration in the STN-COWP PCR was increased from 2.5 to 5 U. The STN-COWP PCR assay amplified 90 of 92 samples (97.8%) and the MAS-PCR assay amplified 70 of 92 samples (76.1%) tested. In the absence of inhibitors, DNA equivalent to 3 C. parvum oocysts was amplified.
    Journal of Microbiological Methods 07/2006; 65(3):512-24. · 2.16 Impact Factor
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    ABSTRACT: Cryptosporidiosis and giardiasis are major public health concerns. The role of water and food in the epidemiology of these diseases is now well recognized. Molecular techniques are available to determine the species and genotypes of Cryptosporidium and Giardia and to distinguish human from non-human pathogens. Validated methods to determine the species, genotype and subgenotype that are present in heterologous mixtures should be applied to environmental samples to enable the monitoring and characterization of infection sources, disease tracking and the establishment of causative links to both waterborne and foodborne outbreaks. Meaningful interpretation of population structures and occurrence-prevalence baselines can be performed only by analysing a well-planned set of samples from all possible sources taken regularly over time, rather than focusing on outbreak investigations. For food, this includes such analyses in the country of origin.
    Trends in Parasitology 05/2006; 22(4):160-7. · 5.51 Impact Factor
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    ABSTRACT: Molecular biology has provided insights into the taxonomy and epidemiology of Cryptosporidium and Giardia, which are major causes of protozoal diarrhoea in humans worldwide. For both genera, previously unrecognized differences in disease, symptomatology, zoonotic potential, risk factors and environmental contamination have been identified using molecular tools that are appropriate for species, genotype and subtype analysis. In this article, to improve understanding of the epidemiology of cryptosporidiosis and giardiasis, we consider specific requirements for the development of more-effective molecular identification and genotyping systems that should be applicable to both clinical and environmental samples.
    Trends in Parasitology 10/2005; 21(9):430-7. · 5.51 Impact Factor
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    ABSTRACT: Cryptosporidium parvum excystation and host cell invasion have been characterized in some detail ultrastructurally. However, until recently, the biochemical and molecular basis of host-parasite interactions and parasite- and host-specific molecules involved in excystation, motility and host cell invasion have been poorly understood. This article describes our understanding of Cryptosporidium excystation and the events leading to host cell invasion, and draws from information available about these processes in other apicomplexans. Many questions remain but, once the specific mechanisms are identified, they could prove to be novel targets for drug delivery.
    Trends in Parasitology 04/2005; 21(3):133-42. · 5.51 Impact Factor
  • Huw V Smith, Gerard D Corcoran
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    ABSTRACT: There is a history of inadequate treatments for cryptosporidiosis and a lack of understanding of the species that cause human disease. Against this background, we review the efficacy of antiparasitic agents, particularly nitazoxanide, which has led to increased treatment options, the potential for immunotherapy, and consider the role of highly active antiretroviral therapy in reducing the incidence of this opportunistic infection. Nitazoxanide is effective for cryptosporidiosis in immunocompetent and probably immunocompromised patients (with an alteration in the duration of treatment or the dosing regimen). HIV-infected patients on highly active antiretroviral therapy have a dramatically lower incidence of cryptosporidiosis, attributable to the effects of intestinal immune reconstitution as well as the effect on the CD4 cell count. Protease inhibitors have a direct inhibitory effect on Cryptosporidium infection, suggesting a further reason for the reduction in the incidence of cryptosporidiosis and implying a further possible therapeutic modality. Cryptosporidiosis remains a significant public health threat. Risk avoidance guidance could be viewed in the more relative terms of risk management depending on the degree of immunosuppression. Of established efficacy in immunocompetent patients, nitazoxanide is also useful for immunocompromised patients. Better prevention and treatment options mean that, in the immunocompromised, this disease is now less common. Immune reconstitution is the key to prevention. Further database mining of the Cryptosporidium genome will assist in the discovery of new genes, biochemical pathways and protective antigens that can be targeted to develop novel therapies for cryptosporidiosis.
    Current Opinion in Infectious Diseases 01/2005; 17(6):557-64. · 5.03 Impact Factor

Publication Stats

622 Citations
74.17 Total Impact Points

Institutions

  • 2011
    • University of Melbourne
      • Veterinary Science Library
      Melbourne, Victoria, Australia
  • 2009
    • University of Malaya
      • Department of Parasitology
      Kuala Lumpur, Kuala Lumpur, Malaysia
  • 2005–2009
    • The Bracton Centre, Oxleas NHS Trust
      Дартфорде, England, United Kingdom
    • Istituto Superiore di Sanità
      • Department of Infectious, Parasitic and Immune-mediated Diseases
      Roma, Latium, Italy