Absence of Cryptosporidium hominis and dominance of zoonotic Cryptosporidium species in patients after Covid-19 restrictions in Auckland, New Zealand

Abstract Background Cryptosporidium is a leading cause of moderate to severe childhood diarrhea in resource-poor settings. Understanding the natural history of cryptosporidiosis and the correlates of protection are essential to develop effective and sustainable approaches to disease control and prevention. Methods Children (N = 497) were recruited at birth in semiurban slums in Vellore, India, and followed for 3 years with twice-weekly home visits. Stool samples were collected every 2 weeks and during diarrheal episodes were tested for Cryptosporidium species by polymerase chain reaction (PCR). Serum samples obtained every 6 months were evaluated for seroconversion, defined as a 4-fold increase in immunoglobulin G directed against Cryptosporidium gp15 and/or Cp23 antigens between consecutive sera. Results Of 410 children completing follow-up, 397 (97%) acquired cryptosporidiosis by 3 years of age. PCR identified 1053 episodes of cryptosporidiosis, with an overall incidence of 0.86 infections per child-year by stool and serology. The median age for the first infection was 9 (interquartile range, 4–17) months, indicating early exposure. Although infections were mainly asymptomatic (693 [66%]), Cryptosporidium was identified in 9.4% of diarrheal episodes. The proportion of reinfected children was high (81%) and there was clustering of asymptomatic and symptomatic infections (P < .0001 for both). Protection against infection increased with the order of infection but was only 69% after 4 infections. Cryptosporidium hominis (73.3%) was the predominant Cryptosporidium species, and there was no species-specific protection. Conclusions There is a high burden of endemic cryptosporidiosis in southern India. Clustering of infection is suggestive of host susceptibility. Multiple reinfections conferred some protection against subsequent infection.

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Genetic Characterization and Transmission Cycles of Cryptosporidium Species Isolated from Humans in New Zealand

Applied and Environmental Microbiology ◽

10.1128/aem.70.7.3973-3978.2004 ◽

2004 ◽

Vol 70 (7) ◽

pp. 3973-3978 ◽

Cited By ~ 71

Author(s):

James J. Learmonth ◽

George Ionas ◽

Kim A. Ebbett ◽

Errol S. Kwan

Keyword(s):

New Zealand ◽

Sequence Analysis ◽

Dna Sequence ◽

Dna Sequence Analysis ◽

Urban Region ◽

Cryptosporidium Hominis ◽

Genetic Characteristics ◽

Rural And Urban ◽

Close Relationship ◽

Transmission Cycles

ABSTRACT Little is known about the genetic characteristics, distribution, and transmission cycles of Cryptosporidium species that cause human disease in New Zealand. To address these questions, 423 fecal specimens containing Cryptosporidium oocysts and obtained from different regions were examined by the PCR-restriction fragment length polymorphism technique. Indeterminant results were resolved by DNA sequence analysis. Two regions supplied the majority of isolates: one rural and one urban. Overall, Cryptosporidium hominis accounted for 47% of the isolates, with the remaining 53% being the C. parvum bovine genotype. A difference, however, was observed between the Cryptosporidium species from rural and urban isolates, with C. hominis dominant in the urban region, whereas the C. parvum bovine genotype was prevalent in rural New Zealand. A shift in transmission cycles was detected between seasons, with an anthroponotic cycle in autumn and a zoonotic cycle in spring. A novel Cryptosporidium sp., which on DNA sequence analysis showed a close relationship with C. canis, was detected in two unrelated children from different regions, illustrating the genetic diversity within this genus.

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Draft Genome Assemblies of Two Cryptosporidium hominis Isolates from New Zealand

Microbiology Resource Announcements ◽

10.1128/mra.00363-21 ◽

2021 ◽

Vol 10 (26) ◽

Author(s):

M. A. Knox ◽

J. C. Garcia-R ◽

D. T. S. Hayman

Keyword(s):

New Zealand ◽

Gastrointestinal Disease ◽

Draft Genome ◽

Protozoan Parasite ◽

Clinical Isolates ◽

Whole Genome ◽

Genome Sequences ◽

Cryptosporidium Hominis ◽

Content Type ◽

Genome Assemblies

Cryptosporidium hominis is a protozoan parasite that causes gastrointestinal disease in humans worldwide. Here, we report on draft whole-genome sequences of two clinical isolates of C. hominis that were purified from patients with cryptosporidiosis in New Zealand.

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A Review of the Prevalence and Diagnostic Points of Cryptosporidium Species in Immunocompromised and Healthy Human Samples in Iran

Disease and Diagnosis ◽

10.34172/ddj.2021.30 ◽

2021 ◽

Vol 10 (4) ◽

pp. 169-176

Author(s):

Soudabeh Etemadi ◽

Omid Raiesi ◽

Muhammad I. Getso ◽

Vahid Raissi ◽

Hosnie Hoseini

Keyword(s):

Study Data ◽

Cryptosporidium Species ◽

Cryptosporidium Hominis ◽

Healthy Human ◽

Immune Systems ◽

Human Samples ◽

Iranian Studies ◽

The World ◽

Intestinal Pathogens ◽

Review Study

Cryptosporidium species are important intestinal pathogens with widespread distribution in humans and other hosts. Whereas the parasite causes acute and self-limiting gastroenteritis in people with healthy immune systems, many reports on this infection around the world are limited to people with defective or suppressed immune systems who suffer from a persistent and deadly infection. Using laboratory-serological and molecular methods for the detection of Cryptosporidium species in immunocompromised and healthy human samples, recent studies in Iran indicated that the prevalence of Cryptosporidium species in different samples varied between 0 to 14%. The samples in Iranian studies included human fecal and diarrheic samples from diarrheic children, patients with gastroenteritis, immunocompromised individuals, and people in contact with livestock. Furthermore, some species were reported based on molecular studies including Cryptosporidium parvum and Cryptosporidium hominis. Some studies have also reported Cryptosporidium meleagridis. In this review study, data were collected regarding the prevalence of cryptosporidiosis in high-risk individuals such as children and immunocompromised individuals. The results revealed that the higher prevalence of C. parvum in Iranian studies in the last 10 years may be attributed to the transmission of infection from animal sources.

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Magellanic Cloud Eclipsing Binaries: Primary Distance Indicators

Symposium - International Astronomical Union ◽

10.1017/s007418090011900x ◽

1999 ◽

Vol 190 ◽

pp. 563-566

Author(s):

J. D. Pritchard ◽

W. Tobin ◽

J. V. Clausen ◽

E. F. Guinan ◽

E. L. Fitzpatrick ◽

...

Keyword(s):

New Zealand ◽

Magellanic Cloud ◽

Eclipsing Binaries ◽

Fundamental Parameters ◽

Distance Indicators

Our collaboration involves groups in Denmark, the U.S.A. Spain and of course New Zealand. Combining ground-based and satellite (IUEandHST) observations we aim to determine accurate and precise stellar fundamental parameters for the components of Magellanic Cloud Eclipsing Binaries as well as the distances to these systems and hence the parent galaxies themselves. This poster presents our latest progress.

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Heat-Etching with a Bullivant Type II Simple Freeze-Cleave Device

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100067522 ◽

1970 ◽

Vol 28 ◽

pp. 106-107 ◽

Cited By ~ 1

Author(s):

Ronald S. Weinstein ◽

N. Scott McNutt

Keyword(s):

New Zealand ◽

General Hospital ◽

Massachusetts General Hospital ◽

Type I ◽

Type Ii ◽

Collaborative Effort ◽

Temperature And Pressure ◽

The University

The Type I simple cold block device was described by Bullivant and Ames in 1966 and represented the product of the first successful effort to simplify the equipment required to do sophisticated freeze-cleave techniques. Bullivant, Weinstein and Someda described the Type II device which is a modification of the Type I device and was developed as a collaborative effort at the Massachusetts General Hospital and the University of Auckland, New Zealand. The modifications reduced specimen contamination and provided controlled specimen warming for heat-etching of fracture faces. We have now tested the Mass. General Hospital version of the Type II device (called the “Type II-MGH device”) on a wide variety of biological specimens and have established temperature and pressure curves for routine heat-etching with the device.

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A Cytochemical Study of Glucose-6-Phosphatase (G-6-PASE) in Cells Participating in Atherogenesis of Rabbit Aorta

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100115924 ◽

1975 ◽

Vol 33 ◽

pp. 460-461

Author(s):

Sidney D. Kobernick ◽

Edna A. Elfont ◽

Neddra L. Brooks

Keyword(s):

Lipid Metabolism ◽

New Zealand ◽

Aortic Wall ◽

Rabbit Aorta ◽

Plaque Formation ◽

Metabolic Changes ◽

Atherosclerotic Plaques ◽

Cytochemical Study ◽

Cellular Alteration ◽

New Zealand White Rabbits

This cytochemical study was designed to investigate early metabolic changes in the aortic wall that might lead to or accompany development of atherosclerotic plaques in rabbits. The hypothesis that the primary cellular alteration leading to plaque formation might be due to changes in either carbohydrate or lipid metabolism led to histochemical studies that showed elevation of G-6-Pase in atherosclerotic plaques of rabbit aorta. This observation initiated the present investigation to determine how early in plaque formation and in which cells this change could be observed.Male New Zealand white rabbits of approximately 2000 kg consumed normal diets or diets containing 0.25 or 1.0 gm of cholesterol per day for 10, 50 and 90 days. Aortas were injected jin situ with glutaraldehyde fixative and dissected out. The plaques were identified, isolated, minced and fixed for not more than 10 minutes. Incubation and postfixation proceeded as described by Leskes and co-workers.

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