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Gargala G, Razakandrainibe R, Costa D, Leméteil D, Dumant Forest C. La cryptosporidiose, une cause de diarrhée aiguë : revue de la littérature et étude rétrospective des cas dans le département de pédiatrie du CHU de Rouen. Arch Pediatr 2017; 24:1344-1349. [DOI: 10.1016/j.arcped.2017.10.002] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2017] [Revised: 10/02/2017] [Accepted: 10/03/2017] [Indexed: 11/28/2022]
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Lin H, Yusin J. A protracted case of diarrhoea caused by Cryptosporidium in a non-immunocompromised patient. Allergol Immunopathol (Madr) 2014; 42:500-1. [PMID: 23791507 DOI: 10.1016/j.aller.2013.02.015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2013] [Accepted: 02/26/2013] [Indexed: 10/26/2022]
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Abstract
PURPOSE OF REVIEW The global significance of cryptosporidiosis is widespread and far-reaching. In this review, we present recent data about strain diversity and the burden of disease, along with developments in therapeutic and preventive strategies. RECENT FINDINGS Cryptosporidium is an emerging pathogen that disproportionately affects children in developing countries and immunocompromised individuals. Without a diagnostic tool amenable for use in developing countries, the burden of infection and its relationship to growth faltering, malnutrition, and diarrheal mortality remain underappreciated. Disease incidence is also increasing in industrialized countries largely as a result of outbreaks in recreational water facilities. Advances in molecular methods, including subtyping analysis, have yielded new insights into the epidemiology of cryptosporidiosis. However, without practical point-of-care diagnostics, an effective treatment for immunocompromised patients, and a promising vaccine candidate, the ability to reduce the burden of disease in the near future is limited. This is compounded by inadequate coverage with antiretroviral therapy in developing countries, the only current means of managing HIV-infected patients with cryptosporidiosis. SUMMARY Cryptosporidiosis is one of the most important diarrheal pathogens affecting people worldwide. Effective methods to control and treat cryptosporidiosis among high-risk groups present an ongoing problem in need of attention.
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Lima AA, Samie A, Guerrant RL. Cryptosporidiosis. TROPICAL INFECTIOUS DISEASES: PRINCIPLES, PATHOGENS AND PRACTICE 2011:633-640. [DOI: 10.1016/b978-0-7020-3935-5.00094-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/04/2025]
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Abstract
Food- and water-borne infections have afflicted mankind since the earliest days of human development and preceded the emergence of civilization. Despite current knowledge of microbial pathogenicity, modern methods of food production and rigorous industrial hygiene, these infections are still commonplace and exact significant health and economic tolls on human populations in all parts of the globe. This review uses data derived from new surveillance networks to survey the current epidemiology of bacterial, protozoan and viral pathogens transmitted by food and water. In addition, we will discuss clinical features of human disease caused by pathogens of current and emerging relevance.
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Egorov AI, Montuori Trimble LM, Ascolillo L, Ward HD, Levy DA, Morris RD, Naumova EN, Griffiths JK. Recent diarrhea is associated with elevated salivary IgG responses to Cryptosporidium in residents of an eastern Massachusetts community. Infection 2010; 38:117-23. [PMID: 20349105 DOI: 10.1007/s15010-009-9323-4] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2009] [Accepted: 12/16/2009] [Indexed: 11/24/2022]
Abstract
BACKGROUND Serological data suggest that Cryptosporidium infections are common but underreported. The invasiveness of blood sampling limits the application of serology in epidemiological surveillance. We pilot-tested a non-invasive salivary anti-Cryptosporidium antibody assay in a community survey involving children and adults. MATERIALS AND METHODS Families with children were recruited in a Massachusetts community in July; symptoms data were collected at 3 monthly follow-up mail surveys. One saliva sample per person (n = 349) was collected via mail, with the last survey in October. Samples were analyzed for IgG and IgA responses to a recombinant C. hominis gp15 sporozoite protein using a time-resolved fluorometric immunoassay. Log-transformed assay results were regressed on age using penalized B-splines to account for the strong age-dependence of antibody reactions. Positive responses were defined as fluorescence values above the upper 99% prediction limit. RESULTS Forty-seven (13.5%) individuals had diarrhea without concurrent respiratory symptoms during the 3-month-long follow-up; eight of them had these symptoms during the month prior to saliva sampling. Two individuals had positive IgG responses: an adult who had diarrhea during the prior month and a child who had episodes of diarrhea during each survey month (Fisher's exact test for an association between diarrhea and IgG response: p = 0.0005 for symptoms during the prior month and p = 0.02 for symptoms during the entire follow-up period). The child also had a positive IgA response, along with two asymptomatic individuals (an association between diarrhea and IgA was not significant). CONCLUSION These results suggest that the salivary IgG specific to Cryptosporidium antigens warrants further evaluation as a potential indicator of recent infections.
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Affiliation(s)
- A I Egorov
- National Center for Environmental Assessment, US Environmental Protection Agency, 26 W. Martin Luther King Drive, Mail Stop A110, Cincinnati, OH 45268, USA.
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Kaushik K, Khurana S, Wanchu A, Malla N. Serum immunoglobulin G, M and A response to Cryptosporidium parvum in Cryptosporidium-HIV co-infected patients. BMC Infect Dis 2009; 9:179. [PMID: 19922628 PMCID: PMC2784774 DOI: 10.1186/1471-2334-9-179] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2008] [Accepted: 11/18/2009] [Indexed: 11/18/2022] Open
Abstract
Background Cryptosporidium parvum, the protozoan parasite, causes a significant enteric disease in immunocompromised hosts such as HIV patients. The present study was aimed to compare serum IgG, IgM and IgA responses to crude soluble antigen of C. parvum in HIV seropositive and seronegative patients co-infected with Cryptosporidium and to correlate the responses with symptomatology. Methods Cryptosporidium parvum specific serum antibody (IgG, IgM and IgA) responses were assessed by ELISA in 11 HIV seropositive Cryptosporidium positive (Group I), 20 HIV seropositive Cryptosporidium negative (Group II), 10 HIV seronegative Cryptosporidium positive (Group III), 20 HIV seronegative Cryptosporidium negative healthy individuals (Group IV) and 25 patients with other parasitic diseases (Group V). Results A positive IgG and IgA antibody response was observed in significantly higher number of Cryptosporidium infected individuals (Gp I and III) compared to Cryptosporidium un-infected individuals (Gp II, IV and V) irrespective of HIV/immune status. Sensitivity of IgG ELISA in our study was found to be higher as compared to IgM and IgA ELISA. The number of patients with positive IgG, IgM and IgA response was not significantly different in HIV seropositive Cryptosporidium positive patients with diarrhoea when compared to patients without diarrhoea and in patients with CD4 counts <200 when compared to patients with CD4 counts >200 cells/μl. Conclusion The study showed specific serum IgG and IgA production in patients infected with Cryptosporidium, both HIV seropositive and seronegative as compared to uninfected subjects suggesting induction of Cryptosporidium specific humoral immune response in infected subjects. However, there was no difference in number of patients with positive response in HIV seropositive or seronegative groups indicating that HIV status may not be playing significant role in modulation of Cryptosporidium specific antibody responses. The number of patients with positive IgG, IgM and IgA response was not significantly different in patients with or without history of diarrhoea thereby indicating that Cryptosporidium specific antibody responses may not be necessarily associated with protection from symptomatology.
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Affiliation(s)
- Kirti Kaushik
- Department of Parasitology, Postgraduate Institute of Medical Education and Research, Chandigarh-160 012, India.
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Lee JK, Han ET, Huh S, Park WY, Yu JR. A hospital-based serological survey of cryptosporidiosis in the Republic of Korea. THE KOREAN JOURNAL OF PARASITOLOGY 2009; 47:219-25. [PMID: 19724694 DOI: 10.3347/kjp.2009.47.3.219] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/01/2009] [Revised: 06/22/2009] [Accepted: 06/25/2009] [Indexed: 11/23/2022]
Abstract
The seroprevalence of cryptosporidiosis was examined using patients' sera collected from hospitals located in 4 different areas of the Republic of Korea. ELISA was used to measure antibody titers against Cryptosporidium parvum antigens from a total of 2,394 serum samples, which were collected randomly from patients in local hospitals; 1) Chungbuk National University Hospital, 2) Konkuk University Hospital, 3) local hospitals in Chuncheon, Gangwon-do (province), 4) Jeonnam National University Hospital, from 2002 through 2003. Of the 2,394 samples assayed, 34%, 26%, and 56% were positive for C. parvum-specific IgG, IgM, and IgA antibodies, respectively. Positive IgG titers were most common in sera from Jeonnam National University Hospital, Gwangju, Jeollanam-do, and positive IgM titers were most common in sera from Chungbuk National University Hospital, Cheongju, Chuncheongbuk-do. The seropositivity was positively correlated with age for both the IgG and IgA antibodies but was negatively correlated with age for the IgM antibodies. Western blotting revealed that 92%, 83%, and 77% of sera positive for IgG, IgM, and IgA ELISA reacted with 27-kDa antigens, respectively. These results suggested that infection with Cryptosporidium in hospital patients occurs more commonly than previously reported in the Republic of Korea.
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Affiliation(s)
- Jong-Kyu Lee
- Department of Environmental and Tropical Medicine, Konkuk University School of Medicine, Seoul, Korea
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Nascimento WRCD, Cavalcanti IMF, Irmão JI, Rocha FJS. [Presence of Cryptosporidium spp in children with acute diarrhea in a public daycare center in Recife, State of Pernambuco]. Rev Soc Bras Med Trop 2009; 42:175-8. [PMID: 19448937 DOI: 10.1590/s0037-86822009000200016] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2008] [Accepted: 03/20/2009] [Indexed: 11/22/2022] Open
Abstract
The objective of the present study was to analyze the frequency of oocysts of Cryptosporidium spp in fecal samples from children aged one to fourteen years at a public daycare center located in a needy community in the city of Recife, Pernambuco. The investigation was carried out between June 28, 2006, and April 3, 2007, and involved 182 children. Among the samples analyzed, 59 (32.4%) were positive regarding the presence of oocysts of Cryptosporidium spp, and the age group most affected was between three and five years (54.2%). The high frequency of samples positive for Cryptosporidium spp obtained in this study confirms that daycare centers are an environment that favors such occurrences, because of the direct contact between children or between children and staff. The most important infection route for Cryptosporidium spp is person-to-person transmission, which is well illustrated in daycare centers. Immaturity, deficiencies of the immune system and inadequate hygiene habits are factors that also contribute towards this type of infection.
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Ochoa TJ, White AC. CRYPTOSPORIDIOSIS. FEIGIN AND CHERRY'S TEXTBOOK OF PEDIATRIC INFECTIOUS DISEASES 2009:2869-2880. [DOI: 10.1016/b978-1-4160-4044-6.50233-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/04/2025]
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Tan KSW. New insights on classification, identification, and clinical relevance of Blastocystis spp. Clin Microbiol Rev 2008; 21:639-65. [PMID: 18854485 PMCID: PMC2570156 DOI: 10.1128/cmr.00022-08] [Citation(s) in RCA: 476] [Impact Index Per Article: 28.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
SUMMARY Blastocystis is an unusual enteric protozoan parasite of humans and many animals. It has a worldwide distribution and is often the most commonly isolated organism in parasitological surveys. The parasite has been described since the early 1900s, but only in the last decade or so have there been significant advances in our understanding of Blastocystis biology. However, the pleomorphic nature of the parasite and the lack of standardization in techniques have led to confusion and, in some cases, misinterpretation of data. This has hindered laboratory diagnosis and efforts to understand its mode of reproduction, life cycle, prevalence, and pathogenesis. Accumulating epidemiological, in vivo, and in vitro data strongly suggest that Blastocystis is a pathogen. Many genotypes exist in nature, and recent observations indicate that humans are, in reality, hosts to numerous zoonotic genotypes. Such genetic diversity has led to a suggestion that previously conflicting observations on the pathogenesis of Blastocystis are due to pathogenic and nonpathogenic genotypes. Recent epidemiological, animal infection, and in vitro host-Blastocystis interaction studies suggest that this may indeed be the case. This review focuses on such recent advances and also provides updates on laboratory and clinical aspects of Blastocystis spp.
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Affiliation(s)
- Kevin S W Tan
- Department of Microbiology, Laboratory of Molecular and Cellular Parasitology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Republic of Singapore.
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Teixeira MCA, Barreto ML, Melo C, Silva LR, Moraes LRS, Alcântara-Neves NM. A serological study of Cryptosporidium transmission in a periurban area of a Brazilian Northeastern city. Trop Med Int Health 2007; 12:1096-104. [PMID: 17714433 DOI: 10.1111/j.1365-3156.2007.01892.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
OBJECTIVES To study the prevalence of Cryptosporidium infection by measuring the levels of anti-Cryptosporidium IgG antibodies among people inhabiting three neighbourhoods of a periurban area of Salvador, Northeast of Brazil; and to investigate the effects of environmental sanitation measures, hygienic habits and household water supply, storage and handling on the frequency of these antibodies in sera of the studied population. METHODS Cryptosporidium inter-household transmission was studied by comparing the frequency of anti-Cryptosporidium IgG antibodies among people inhabiting areas with or without different environmental sanitation measures and intra-household transmission by comparing the presence of these antibodies in families with or without cases of diarrhoea, associated with the presence of Cryptosporidium oocysts in their stools. Children or family members with diarrhoeal episodes were evaluated parasitologically for Cryptosporidium infection by testing stool specimens with the Ritchie-modified formol-ether concentration and the acid-fast staining methods. All groups were serologically evaluated for parasite exposure by an indirect enzyme-linked immunosorbent assay. RESULTS A statistically significant difference was detected in the prevalence of Cryptosporidium infection between area 1 which had no environmental sanitation measures and area 3 which had improved environmental sanitation measures (P = 0.044). Most of the hygienic habits investigated did not correlate with the presence of anti-Cryptosporidium antibody in sera of the population studied. However, positive associations were found between both poor household water supply (OD = 0.17; 90% CI = 0.09-0.32; P = 0.0001) and drinking unboiled/unfiltered water (OD = 0.40; 90% CI = 0.24-0.67; P = 0.0002) with high levels of anti-Cryptosporidium antibodies in sera. CONCLUSIONS These data suggest that although uncorrected household water supply, storage and handling play an important role on Cryptosporidium transmission in periurban areas of developing country cities, like Salvador, Brazil, inadequate environmental conditions may also contribute to the spread of this parasite.
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Affiliation(s)
- M C A Teixeira
- Faculdade de Farmácia, Universidade Federal da Bahia, Bahia, Brazil.
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Boulter-Bitzer JI, Lee H, Trevors JT. Molecular targets for detection and immunotherapy in Cryptosporidium parvum. Biotechnol Adv 2006; 25:13-44. [PMID: 17055210 DOI: 10.1016/j.biotechadv.2006.08.003] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2006] [Revised: 08/14/2006] [Accepted: 08/22/2006] [Indexed: 11/21/2022]
Abstract
Cryptosporidium parvum is an obligate protozoan parasite responsible for the diarrheal illness cryptosporidiosis in humans and animals. Although C. parvum is particularly pathogenic in immunocompromised hosts, the molecular mechanisms by which C. parvum invades the host epithelial cells are not well understood. Characterization of molecular-based antigenic targets of C. parvum is required to improve the specificity of detection, viability assessments, and immunotherapy (treatment). A number of zoite surface (glyco)proteins are known to be expressed during, and believed to be involved in, invasion and infection of host epithelial cells. In the absence of protective treatments for this illness, antibodies targeted against these zoite surface (glyco)proteins offers a rational approach to therapy. Monoclonal, polyclonal and recombinant antibodies represent useful immunotherapeutic means of combating infection, especially when highly immunogenic C. parvum antigens are utilized as targets. Interruption of life cycle stages of this parasite via antibodies that target critical surface-exposed proteins can potentially decrease the severity of disease symptoms and subsequent re-infection of host tissues. In addition, development of vaccines to this parasite based on the same antigens may be a valuable means of preventing infection. This paper describes many of the zoite surface glycoproteins potentially involved in infection, as well as summarizes many of the immunotherapeutic studies completed to date. The identification and characterization of antibodies that bind to C. parvum-specific cell surface antigens of the oocyst and sporozoite will allow researchers to fully realize the potential of molecular-based immunotherapy to this parasite.
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HASIN T, DAGAN R, BOUTBOUL G, DERAZNE E, ATIAS O, COHEN D. Socioeconomic correlates of antibody levels to enteric pathogens among Israeli adolescents. Epidemiol Infect 2006; 135:118-25. [PMID: 16740193 PMCID: PMC2870538 DOI: 10.1017/s0950268806006455] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/22/2006] [Indexed: 11/07/2022] Open
Abstract
We examined the association between socioeconomic status and the level of serum antibodies to selected faeco-orally transmitted pathogens among Israeli adolescents. Random samples of eighty volunteers aged 12-15 years from high (HSL), medium (MSL) and low (LSL) standard of living towns were included in the study. Serum samples were examined by radioimmunoassay for HAV and by in-house-developed ELISA systems for IgA and IgG antibody levels against Shigella sonnei, S. flexneri, E. coli O157:H7 lipopolysacchride and Cryptosporidium parvum antigens. Seropositivity to HAV was highest (98.8%) in the LSL towns and lowest (25%) in the HSL towns, showing a statistically significant linear trend. Antibody levels to the other enteropathogens had gender variation, with higher titres in females. Significantly lower titres in the HSL towns were found for: IgA anti-S. sonnei in females (P<0.001); IgG anti-S. sonnei in females (P=0.024) and males (P=0.033); IgG anti-S. flexneri in females (P=0.016). Inverse linear association with socioeconomic status was found for IgA anti-C. parvum in females (P<0.001); IgA anti-E. coli O157:H7 in females (P<0.001) and males (P=0.024). A statistically significant association between HAV seropositivity and higher titres of IgA anti-S. sonnei and E. coli O157:H7 was shown. In conclusion, exposure to enteropathogens transmitted via the faecal-oral route in communities of lower socioeconomic status is reflected in a higher prevalence of lifelong lasting antibodies to HAV, and higher levels of antibodies to bacterial and protozoan enteropathogens. Among females, the levels of specific serum antibodies are higher and more strongly associated with low socioeconomic status.
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Affiliation(s)
- T. HASIN
- Medical Department, Hadassah Mt Scopus University Hospital, Jerusalem, Israel
- Medical Corps, Israel Defense Force, Military Post 02149
| | - R. DAGAN
- Pediatric Infectious Diseases Unit, Soroka University Medical Center and the Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer-Sheva, Israel
| | - G. BOUTBOUL
- Medical Corps, Israel Defense Force, Military Post 02149
- Department of Epidemiology and Preventive Medicine, Sackler Faculty of Medicine, Tel-Aviv University, Israel
| | - E. DERAZNE
- Medical Corps, Israel Defense Force, Military Post 02149
| | - O. ATIAS
- Pediatric Infectious Diseases Unit, Soroka University Medical Center and the Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer-Sheva, Israel
- Department of Pediatrics, Soroka University Medical Center and the Faculty of Health Sciences, Ben Gurion University of the Negev, Beer-Sheva, Israel
| | - D. COHEN
- Department of Epidemiology and Preventive Medicine, Sackler Faculty of Medicine, Tel-Aviv University, Israel
- Author for correspondence: Professor D. Cohen, Department of Epidemiology and Preventive Medicine, Sackler Faculty of Medicine, Tel-Aviv University, Ramat Aviv, Tel Aviv, 69978, Israel. ()
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Abstract
Cryptosporidium and Giardia are two of the most commonly occurring enteric protozoans. They are responsible for diarrheal diseases that may lead to nutritional deficiencies and significant morbidity and mortality, especially among children in developing countries and patients who have immune defects. Both are difficult to diagnose with microscopic techniques. This article provides an updated review of the epidemiology, pathogenesis, clinical manifestations, and treatment of Cryptosporidium and Giardia.
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Affiliation(s)
- David B Huang
- Division of Infectious Diseases, Department of Medicine, Baylor College of Medicine, One Baylor Plaza, 535EE, Houston, TX 77030, USA
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Roy SL, DeLong SM, Stenzel SA, Shiferaw B, Roberts JM, Khalakdina A, Marcus R, Segler SD, Shah DD, Thomas S, Vugia DJ, Zansky SM, Dietz V, Beach MJ. Risk factors for sporadic cryptosporidiosis among immunocompetent persons in the United States from 1999 to 2001. J Clin Microbiol 2004; 42:2944-51. [PMID: 15243043 PMCID: PMC446318 DOI: 10.1128/jcm.42.7.2944-2951.2004] [Citation(s) in RCA: 118] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2003] [Revised: 02/01/2004] [Accepted: 03/28/2004] [Indexed: 11/20/2022] Open
Abstract
Many studies have evaluated the role of Cryptosporidium spp. in outbreaks of enteric illness, but few studies have evaluated sporadic cryptosporidiosis in the United States. To assess the risk factors for sporadic cryptosporidiosis among immunocompetent persons, a matched case-control study was conducted in seven sites of the Foodborne Diseases Active Surveillance Network (FoodNet) involving 282 persons with laboratory-identified cryptosporidiosis and 490 age-matched and geographically matched controls. Risk factors included international travel (odds ratio [OR] = 7.7; 95% confidence interval [95% CI] = 2.7 to 22.0), contact with cattle (OR = 3.5; 95% CI = 1.8 to 6.8), contact with persons >2 to 11 years of age with diarrhea (OR = 3.0; 95% CI = 1.5 to 6.2), and freshwater swimming (OR = 1.9; 95% CI = 1.049 to 3.5). Eating raw vegetables was protective (OR = 0.5; 95% CI = 0.3 to 0.7). This study underscores the need for ongoing public health education to prevent cryptosporidiosis, particularly among travelers, animal handlers, child caregivers, and swimmers, and the need for further assessment of the role of raw vegetables in cryptosporidiosis.
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Affiliation(s)
- Sharon L Roy
- Division of Parasitic Diseases, National Center for Infectious Diseases, Centers for Disease Control and Prevention, 1600 Clifton Rd., Mailstop E52, Atlanta, GA 30333, USA.
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Abstract
Cryptosporidium was first recognized in humans in 1976 and came to prominence in the 1980s and 1990s as a cause of severe diarrheal illness in patients with AIDS. Its hardy, chlorine-resistant oocysts, tiny size, low infectious dose, fully infectious development when shed and zoonotic potential make it a threat in drinking and recreational water, contaminated food, day care centers, hospitals, and in persons with exposure to animals or unsanitary conditions, with potentially huge, long-term impact in malnourished children, as reviewed herein.
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Affiliation(s)
- Rebecca A Dillingham
- Division of Geographic and International Medicine, University of Virginia School of Medicine, Health Sciences Center, P.O. Box 801379, Charlottesville, VA 22908-1379, USA
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Robin G, Fraser D, Orr N, Sela T, Slepon R, Ambar R, Dagan R, Le Blancq S, Deckelbaum RJ, Cohen D. Cryptosporidium infection in Bedouin infants assessed by prospective evaluation of anticryptosporidial antibodies and stool examination. Am J Epidemiol 2001; 153:194-201. [PMID: 11159166 DOI: 10.1093/aje/153.2.194] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
An enzyme-linked immunosorbent assay system using oocyst lysate as antigen was used to detect serum- specific antibody responses to Cryptosporidium parvum between 1989 and 1994 in consecutive sera obtained at birth, and at the age of 6, 12, and 23 months, from 52 infants living in a Bedouin town located in the south of Israel. The serologic tests revealed high levels of immunoglobulin G anti-Cryptosporidium at birth that dropped significantly by the age of 6 months and then rose continuously to a geometric mean titer of 481 at age 23 months. The serum immunoglobulin M Cryptosporidium antibodies rose continuously from nearly undetectable levels at birth to a geometric mean titer of 471 (157-fold increase) at age 23 months. All the subjects already showed at 6 months a significant rise in immunoglobulin M. A significant rise in immunoglobulin A titers was detected in 48% and 91% of subjects at 6 and 23 months, respectively. By monthly surveillance, microscopy using the modified Ziehl-Neelsen method and confirmed by indirect immunofluorescence assay detected Cryptosporidium antigens in only 11% at age 6 months and 48% at age 23 months. The extent of exposure to Cryptosporidium immediately after birth as detected by serology is much higher than that predicted by frequent prospective assessment of stool samples.
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Affiliation(s)
- G Robin
- Army Health Branch Research Unit, Medical Corps, Israel Defense Force
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Casemore DP. Human Cryptosporidiosis: Clinical Aspects, Epidemiology and Control. J R Coll Physicians Edinb 2000. [DOI: 10.1177/147827150003000403] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Affiliation(s)
- D. P. Casemore
- Centre for Research into Environment and Health, Denbighshire
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Frost FJ, Fea E, Gilli G, Biorci F, Muller TM, Craun GF, Calderon RL. Serological evidence of Cryptosporidium infections in southern Europe. Eur J Epidemiol 2000; 16:385-90. [PMID: 10959948 DOI: 10.1023/a:1007654226975] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Although cryptosporidiosis outbreaks have been frequently reported in the United States, Canada and the United Kingdom, few outbreaks have been reported on the European continent. The reasons for this are unclear. To ascertain whether a European population has been previously exposed to Cryptosporidium, we conducted a survey of 100 resident blood donors in a northern Italian city for IgG serological response to two oocyst antigen groups. A serological response to the 15/17-kDa antigen group was detected in 83% of blood donors and response to the 27-kDa antigen group in 62%. Donors who traveled outside of Italy during the prior 12 months were less likely to have had a response to the 15/17-kDa antigen group (p < 0.04) and to have a less intense response (p < 0.05). Older age was predictive of a more intense response to each antigen group (p < 0.01). The fraction of Italian blood donors with a serological response to either antigen group was higher than in four United States blood donor populations, with differences more pronounced for response to the 15/17-kDa antigen group (p < 0.01). A lower fraction of Italian donors had a serological response to either antigen group than persons tested at the time of a cryptosporidiosis outbreak in the United States or blood donors tested six months after that outbreak (p < 0.05). Since the presence of serological responses to these antigen groups predicts a reduced risk of cryptosporidiosis, the high prevalence of serological responses in these Italian blood donors may explain the infrequent occurrences of clinically detectable cryptosporidiosis in this city.
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Affiliation(s)
- F J Frost
- The Lovelace Clinic Foundation, Albuquerque, New Mexico 87108, USA.
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23
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Hunter PR. Community study of infectious intestinal disease in England. Study underestimated morbidity due to specific pathogens. BMJ (CLINICAL RESEARCH ED.) 1999; 319:258-9. [PMID: 10417107 PMCID: PMC1116348 DOI: 10.1136/bmj.319.7204.258a] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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24
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Nelson SP, Lin PL, Miller J, Katz BZ, Gonzalez-Crussi F. Cryptosporidia enterocolitis in an immunocompetent infant treated with paromomycin. Clin Pediatr (Phila) 1999; 38:367-9. [PMID: 10378096 DOI: 10.1177/000992289903800609] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Affiliation(s)
- S P Nelson
- Department of Pediatrics, Children's Memorial Medical Center, Northwestern University, Chicago, Illinois, USA
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25
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McReynolds CA, Lappin MR, Ungar B, McReynolds LM, Bruns C, Spilker MM, Thrall MA, Reif JS. Regional seroprevalence of Cryptosporidium parvum-specific IgG of cats in the United States. Vet Parasitol 1999; 80:187-95. [PMID: 9950343 DOI: 10.1016/s0304-4017(98)00219-2] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
The objective of this study was to determine the regional prevalence of Cryptosporidium parvum-specific IgG in the sera of cats in the United States. The continental United States was partitioned into eight regional areas. Serum samples from 75 cats from each region were assayed for C. parvum-specific IgG using an indirect enzyme-linked immunosorbent assay (ELISA). Age, sex, breed, and indoor/outdoor status were examined as possible risk factors for developing a positive C. parvum-specific IgG antibody titer. The presence of gastro-intestinal signs and Toxoplasma gondii-specific IgG in the serum were also evaluated for association with C. parvum seropositivity. Of the 600 samples assayed, 50 (8.3%) were positive for C. parvum-specific IgG. Regional seroprevalence ranged from 1.3% in the mid-Atlantic states to 14.7% in the south-eastern states. The oldest group of cats (>10 years) had the highest seroprevalence (15.3%). The prevalence of C. parvum-specific IgG was higher among male (10.1%) than among female cats (6.9%), although, the difference was not statistically significant (p = 0.17). Seropositivity was not associated with pure-bred status. C. parvum-specific IgG antibodies was detected most frequently in T. gondii-specific IgG seropositive cats, outdoor cats, and cats with gastro-intestinal signs. These results suggest that cats in the United States are commonly exposed to C. parvum.
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Affiliation(s)
- C A McReynolds
- Department of Clinical Sciences, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins 80523, USA.
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26
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Okhuysen PC, Chappell CL, Sterling CR, Jakubowski W, DuPont HL. Susceptibility and serologic response of healthy adults to reinfection with Cryptosporidium parvum. Infect Immun 1998; 66:441-3. [PMID: 9453592 PMCID: PMC107924 DOI: 10.1128/iai.66.2.441-443.1998] [Citation(s) in RCA: 140] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Healthy adults are susceptible to infection with small numbers of Cryptosporidium parvum oocysts, resulting in self-limited infection. We investigated if infection of humans with C. parvum is protective 1 year after primary exposure. At 1 year after a primary challenge with 30 to 10(6) oocysts, 19 healthy immunocompetent adults were rechallenged with 500 oocysts and monitored for the development of infection and/or illness. Oocyst excretion was quantitated by direct immunofluorescence with a C. parvum-specific monoclonal antibody, and anti-C. parvum antibodies in serum were detected by an enzyme-linked immunosorbent assay. Fewer subjects shed oocysts after the second exposure (3 of 19; 16%) than after the first exposure (12 of 19; 63%) (P < 0.005). Although the rates of diarrhea were comparable after each of the two exposures, the clinical severity as determined by the mean number of unformed stools passed was lower after reexposure (11.25 versus 8.62; P < 0.05). The number of anti-Cryptosporidium immunoglobulin G and A seroconversions increased after secondary exposure. However, the C. parvum serum antibody response did not correlate with the presence or absence of infection.
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Affiliation(s)
- P C Okhuysen
- Division of Infectious Diseases, The University of Texas Medical School and Center for Infectious Diseases, Houston 77030, USA.
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27
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Russell TS, Lynch J, Ottolini MG. Eradication of Cryptosporidium in a child undergoing maintenance chemotherapy for leukemia using high dose azithromycin therapy. J Pediatr Hematol Oncol 1998; 20:83-5. [PMID: 9482419 DOI: 10.1097/00043426-199801000-00014] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
PURPOSE To describe a case of severe diarrhea caused by Cryptosporidium in a patient undergoing maintenance chemotherapy. Important aspects of disease caused by Cryptosporidium, including diagnosis and treatment, are also reviewed. METHODS AND RESULTS A 4-year-old boy with acute lymphoblastic anemia in remission had a prolonged course of diarrhea and wasting. C. parvum was identified in the gastrointestinal tract by biopsy and in the stool using modified acid fast staining. Improvement in the stool consistency was noted after 3 days of therapy with azithromycin, and, after 14 days of therapy, Cryptosporidium oocysts could no longer be identified in the stool. CONCLUSIONS C. parvum should be considered in all immunocompromised patients with severe or prolonged diarrhea, especially if there is no blood or leukocytes in the stool. Because Cryptosporidium is not always tested for in a routine ova and parasite examination, the lab should be notified if it is in the differential diagnosis. Azithromycin therapy may prove beneficial in the treatment of intestinal Cryptosporidium in immunocompromised individuals.
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Affiliation(s)
- T S Russell
- Department of Pediatric Infectious Diseases, Uniformed Services University of the Health Sciences, Bethesda, Maryland 20814, USA
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28
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Petry F. Epidemiological study of Cryptosporidium parvum antibodies [corrected] in sera of persons from Germany. Infection 1998; 26:7-10. [PMID: 9505172 DOI: 10.1007/bf02768744] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
In a seroprevalence study including 495 sera from persons of all age-groups, the presence of anti-Cryptosporidium parvum antibodies was evaluated in an enzyme immunoassay. Despite the fact that C. parvum is only found in approximately 2% of patients with diarrhea in Germany, specific antibodies could be detected in 15.4% of all samples. This figure indicates that a substantial proportion of the German population has been confronted with this parasite and it raises the question of whether C. parvum is a potential health risk to the general population.
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Affiliation(s)
- F Petry
- Institut für Medizinische Mikrobiologie und Hygiene, Johannes-Gutenberg-Universität Mainz, Germany
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29
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Abstract
Cryptosporidium has become the most important contaminant found in drinking water and is associated with a high risk of waterborne disease particularly for the immunocompromised. There have been 12 documented waterborne outbreaks in North America since 1985; in two of these (Milwaukee and Las Vegas) mortality rates in the immunocompromised ranged from 52% to 68%. The immunofluorescence antibody assay (IFA) using epifluorescence microscopy has been used to examine the occurrence of Cryptosporidium in sewage (1 to 120 oocysts/liter), filtered secondary treated wastewater (0.01 to 0.13 oocysts/liter), surface waters (0.001 to 107 oocysts/liter), groundwater (0.004 to 0.922 oocysts/liter) and treated drinking water (0.001 to 0.72 oocysts/liter). New rules are being developed (Information Collection Rule and Enhanced Surface Water Treatment Rule) to obtain more occurrence data for drinking water systems for use with new risk assessment models. Public health officials should consider a communication program to physicians treating the immunocompromised, nursing homes, develop a plan to evaluate cases of cryptosporidiosis in the community, and contribute to the development of public policies that limit contamination of source waters, improve water treatment, and protect public health.
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Affiliation(s)
- J B Rose
- Department of Marine Sciences, University of South Florida, St. Petersburg 33701, USA.
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Kurtis JD, Ramirez BL, Wiest PM, Dong KL, El-Meanawy A, Petzke MM, Johnson JH, Edmison J, Maier RA, Olds GR. Identification and molecular cloning of a 67-kilodalton protein in Schistosoma japonicum homologous to a family of actin-binding proteins. Infect Immun 1997; 65:344-7. [PMID: 8975937 PMCID: PMC174601 DOI: 10.1128/iai.65.1.344-347.1997] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
A monoclonal antibody to Schistosoma japonicum which conferred significant protection against cercarial challenge in mice was produced. The predicted translation product of the cDNA corresponding to the antigen recognized by this antibody was homologous to a newly identified family of actin-binding proteins. The expressed protein bound polymerized actin and was recognized by serum from patients infected with S. japonicum.
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Affiliation(s)
- J D Kurtis
- International Health Institute, Brown University, Providence, Rhode Island, USA
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31
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Braz LM, Amato Neto V, Ferrari CI, Palhares MC, Amato VS, Santos MT, Marques HH, Vallada M, Nakanishi LS, Andrade Júnior HF. Human cryptosporidiosis: detection of specific antibodies in the serum by an indirect immunofluorescence. Rev Saude Publica 1996; 30:395-402. [PMID: 9269088 DOI: 10.1590/s0034-89101996000500001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Cryptosporidium sp., a coccidian parasite usually found in the faeces of cattle, has been recently implicated as an agent of human intestinal disease, mainly in immunocompromised patients. In the study realized, by an indirect immunofluorescence technique, specific immunoglobulins (IgG and IgM) have been demonstrated in human serum against Cryptosporidium oocysts. Purified oocysts were used as antigens in the indirect immunofluorescence assay. After analyzing this test in sera from selected groups of patients, the frequency of both specific IgG and IgM of immunocompetent children who were excreting oocysts in their faeces was 62% and in children with negative excretion of oocytes was 20% and 40%, respectively. In adults infected with the human immunodeficiency virus (HIV) and who were excreting Cryptosporidium in their stools, the frequency was 57% for IgG but only 2% for IgM. Twenty three percent of immunocompromised adults with not determined excretion of oocysts in their stools had anti-Cryptosporidium IgG in their sera. Children infected with human immunodeficiency virus had no IgM and only 14% had IgG detectable in their sera. The indirect immunofluorescence assay, when used with other parasitological techniques appears to be useful for retrospective population studies and for diagnosis of acute infection. The humoral immune response of HIV positive patients to this protozoan agent needs clarification.
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Affiliation(s)
- L M Braz
- Instituto de Medicina Tropical da Universidade de São Paulo, Brasil.
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Brandonisio O, Marangi A, Panaro MA, Marzio R, Natalicchio MI, Zizzadoro P, De Santis U. Prevalence of Cryptosporidium in children with enteritis in southern Italy. Eur J Epidemiol 1996; 12:187-90. [PMID: 8817198 DOI: 10.1007/bf00145505] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Cryptosporidium parvum is a protozoan which causes self-limiting diarrhea in immunocompetent subjects, and severe life-threatening disease in immunocompromised patients. Cryptosporidiosis is more common in developing countries and in infants. In this paper we have evaluated the prevalence of C. parvum in 368 hospitalized children with enteritis, of whom 359 were immunocompetent and 9 HIV-infected. Stool specimens were concentrated by sedimentation and stained with a modified Ziehl-Neelsen method. Cryptosporidium parvum oocysts were found in 7 (1.90%) out of 368 subjects. Six of these were immunocompetent (with an infection rate in this population of 1.67%) and 1 HIV-infected, asymptomatic except for diarrhea. In all children symptoms of enteritis and oocyst excretion cleared within 10 days. These results indicate that the prevalence of C. parvum as a causative agent of diarrheal illness in hospitalized immunocompetent children is rather low in our region (Apulia, South Italy).
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Affiliation(s)
- O Brandonisio
- Istituto di Microbiologia Medica, Università di Bari, Italy
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Abstract
Cryptosporidium parvum is a protozoan which can cause severe debilitating disease in immunocompromised individuals. Animal models have shown that cellular immunity is the most important factor against the development of the disease. Individuals with a humoral immune deficiency are also at risk. In HIV-infected patients there is a clear relationship between disease severity and CD4 cell counts. Insight into the pathogenesis and development of new agents is hampered by the lack of an in vitro culture system. Prevention is of the utmost importance due to the difficulties of therapy and the severity of clinical disease which can develop. Oocysts are highly resistant to commonly used disinfectants. In HIV-infected patients with cryptosporidiosis, antiretroviral therapy should be instituted or modified. Moreover, non-specific therapy with antidiarrhoeal agents should also be instituted. If no effect is seen, therapy with paromomycin 500 mg 4 times daily for 2-3 weeks should be initiated, followed by maintenance therapy with 500 mg twice daily to prevent relapse.
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Affiliation(s)
- I M Hoepelman
- Department of Medicine, Eijkman Winkler Laboratory for Medical Microbiology, University Hospital, Utrecht, The Netherlands
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Kuhls TL, Orlicek SL, Mosier DA, Crawford DL, Abrams VL, Greenfield RA. Enteral human serum immunoglobulin treatment of cryptosporidiosis in mice with severe combined immunodeficiency. Infect Immun 1995; 63:3582-6. [PMID: 7642294 PMCID: PMC173497 DOI: 10.1128/iai.63.9.3582-3586.1995] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
The anti-cryptosporidial immunoglobulin G antibodies in two commercially available human serum immunoglobulin (HSIG) products were quantified and characterized. The mean level of Cryptosporidium parvum-specific immunoglobulin G in HSIG was eightfold higher than the antibody level found in the sera of three immunocompetent individuals convalescing from cryptosporidiosis. However, HSIG products displayed no reactivity to cryptosporidial antigens in immunoblot analyses, while convalescent-phase sera demonstrated characteristic banding patterns. When HSIG was given to newborn severe combined immunodeficiency (scid) mice before and shortly after experimental infection, a decreased intensity of infection was observed in the intestines of the mice compared with that of control mice. However, there was no difference in mortality or histopathologic findings in the intestines of HSIG-treated and control mice when treatment was not started until 22 days of age. These results indicate that HSIG may be beneficial when given prophylactically; however, HSIG cannot eradicate cryptosporidia from mucosal surfaces in an established infection.
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Affiliation(s)
- T L Kuhls
- Department of Pediatrics, University of Oklahoma Health Sciences Center, Oklahoma City 73104, USA
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35
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DuPont HL, Chappell CL, Sterling CR, Okhuysen PC, Rose JB, Jakubowski W. The infectivity of Cryptosporidium parvum in healthy volunteers. N Engl J Med 1995; 332:855-9. [PMID: 7870140 DOI: 10.1056/nejm199503303321304] [Citation(s) in RCA: 500] [Impact Index Per Article: 16.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
BACKGROUND Small numbers of Cryptosporidium parvum oocysts can contaminate even treated drinking water, and ingestion of oocysts can cause diarrheal disease in normal as well as immunocompromised hosts. Since the number of organisms necessary to cause infection in humans is unknown, we performed a study to determine the infective dose of the parasite in healthy adults. METHODS After providing informed consent, 29 healthy volunteers without evidence of previous C. parvum infection, as determined by the absence of anti-cryptosporidium-specific antibodies, were given a single dose of 30 to 1 million C. parvum oocysts obtained from a calf. They were then monitored for oocyst excretion and clinical illness for eight weeks. Household contacts were monitored for secondary spread. RESULTS Of the 16 subjects who received an intended dose of 300 or more oocysts, 14 (88 percent) became infected. After a dose of 30 oocysts, one of five subjects (20 percent) became infected, whereas at a dose of 1000 or more oocysts, seven of seven became infected. The median infective dose, calculated by linear regression, was 132 oocysts. Of the 18 subjects who excreted oocysts after the challenge dose, 11 had enteric symptoms and 7 (39 percent) had clinical cryptosporidiosis, consisting of diarrhea plus at least one other enteric symptom. All recovered, and there were no secondary cases of diarrhea among household contacts. CONCLUSIONS In healthy adults with no serologic evidence of past infection with C. parvum, a low dose of C. parvum oocysts is sufficient to cause infection.
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Affiliation(s)
- H L DuPont
- University of Texas Medical School, Houston
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