Epidemiological survey of cryptosporidiosis in Anhui Province China

AIM: To provide scientific evidence for prevention and controlling of cryptosporidiosis, the infection of Cryptosporidium parvum and its epidemiological characteristics were studied in some areas of Anhui Province. METHODS: The oocyst of Cryptosporidium parvum in 5421 fresh stool samples from eleven areas of Anhui Province was tested by auramine-phenol stain and improved anti-acid stain respectively. The specific antibody of IgG, IgM and T subsets of 41 patients with positive Cryptosporidium parvum in stools were detected by ELISA and biotin-streptavidin (BSA) respectively. RESULTS: The total infective rate of Cryptosporidium parvum was 1.33% (74/5421). Among them, the positive rates of oocyst in the areas of Huaibei (1.82%) and Fuyang (1.80%) were higher. The positive rates of oocyst in stools of infants, pupils, middle school students, college students, adults, patients with diarrhea, and those with immunodeficiency were 3.15%(28/889), 0.82% (9/1098), 0.82%(9/1092), 0.83%(8/969), 0.85% (9/1095), 2.88%(8/278) and 8.33%(3/36)% respectively. The positive rates of oocyst in infants and the patients with diarrhea and immunodeficiency were significantly higher than those in controls (P【0.01). The positive rate of oocyst in males was similar to that in females (P】0.05). The positive rate of oocyst in urban areas (1.13%) was significantly lower than those in rural areas (1.72%, P【0.01). The positive rates of specific IgG, IgM and IgG+IgM in sera of the patients with positive oocyst in stool were 63.4% (26/41), 17.1% (7/41), 19.5% (8/41) respectively. The number fractions of T subsets of CD(3)(+), CD(4)(+), CD(8)(+) and CD(4)(+)/CD(8)(+) of the patients were 0.66+/-0.07, 0.44+/-0.06, 0.28+/-0.04 and 1.58+/-0.32 respectively. The difference between the patients and the controls was significant (P【0.05). The main manifestations of the patients were subclinical infection, in forms of slight abdominal pain, mild diarrhea, and loose stool. CONCLUSION: There are two infection peaks in infection of Cryptosporidium parvum and its infection can be found more often in infants, patients with diarrhea or immunodeficiency, and in rural areas. Subclinical infection is the main manifestation and might be easily misdiagnosed. When the therapeutic effectiveness is low for diarrhea, the infection of Cryptosporidium parvum should be considered, concerning their age and immune function.

Crypto-Giardia antigen rapid test versus conventional modified Ziehl-Neelsen acid fast staining method for diagnosis of cryptosporidiosis

Objectove:To evaluate the validity of Crypto-Giardia antigen rapid test(CA-RT) in comparison with the conventional mollified Ziehl-Neelsen acid fast(MZN-AF) staining method for the diagnosis of cryptosporidiosis.Methods:Fifteen preserved stool samples from previously confirmed infections were used as positive controls and 40 stool samples from healthy people were used as negative control.A total of 85 stool samples were collected from suspected patients with cryptosporidiosis over 6 months during the period from January till June.2011.The stud) was conducted in the department of parasitology,central laboratory.Alnoor Specialist Hospital, Makkah.Saudi Arabia.All samples were subjected to CA-RT and conventional MZN-AF staining method.Validation parameters including sensitivity(SN).specificity(SP),accuracy index (AI).positive predictive value(PPV).and negative predictive value(NPV) were evaluated for both tests.Results:Out of 15[lositive controls,CA-RT detected 13(86.7%) while MZN-AF detected 11(73.3%) positive cases.However.CA-RT detected no positive case in 40 normal controls but MZN-AF detected 2(5%) as positive cases.Based on the results,the SN.SP.AI.PPV and NPV were high in CA-RT than MZN-AF staining method,ie..86.7%vs.73.3%.100%vs.95%.96.4%vs.89.1%. 100%vs.84.6%and 95.2%vs.90.5%.respectively.Out of a total of 85 suspected specimens.CART detected 7(8.2%) but MZN-AF detected 6(7.1%) cases as positive.Conclusions:CA-RT immunoassay is more valid and reliable than MZN-AF staining method.

Cryptosporidiosis-an overview

Apicomplexan protozoan parasites of the genus Cryptosporidium infect the gastrointestinal tract and lungs of a wide variety of animals, including humans. The majority of human infections are due to either Cryptosporidium hominis （C. hominis） and/or Cryptosporidium parvum （C. parvum）. The parasite has a complex life cycle that includes both asexual and sexual stages. While there are invasive free living stages, proliferation and differentiation take place within a unique parasitrophorous vacuole under the host cell brush border but outside the host cell cytoplasm. Infection is spread by environmentally resistant spores that primarily contaminate drinking water and occasionally food sources, which may cause significant outbreaks of diarrhea that generally lasts less than 2 w in immunocompetent individuals. In immunodeficient or immunosuppressed individuals, diarrhea may be copious and can result in significant morbidity and mortality, particularly in AIDS patients. Although diagnosis is relatively simple, effective drug treatment, particulary for infections in immunodeficient patients, has not been uniformly successful. This overview summarizes the species known to infect humans, aspects of the parasite life cycle, sources of infection, the pathophysiology of cryptosporidiosis, the immune response to infection, diagnosis, treatment and some aspects of cryptosporidiosis in China.

Disseminated cryptosporidiosis:Case report and literature review

Cryptosporidiosis,better known as an intestinal disease may disseminate to infect other sites including the respiratory tract. Little information however is available on respiratory cryptosporidiosis that may largely be due to lower frequency of respiratory cryptosporidiosis. Respiratory cryptosporidiosis has been majorly reported in immunocompromised individuals and children. Here we report a case of respiratory and intestinal cryptosporidiosis in a fifteen months old child with CD8+ deficiency. The patient in spite of treatment with Nitazoxanide and Azithromycin followed by Intravenous immunoglobulin and Bovine colostrum had a fatal outcome. The Cryptosporidium spp. isolate was subjected to molecular characterization. The Cryptosporidium spp. was identified both in stool specimen and Endotracheal aspirate(ETA). The blood sample was negative for Cryptosporidium spp. The Cryptosporidium spp. isolate from stool as well as ETA was identified as Cryptosporidium hominis(C. hominis) using Multiplex Allele Specific Polymerase Chain Reaction assay and was subtyped as Ia A23G1R1 subtype using gp60 gene polymerase chain reaction assay followed by sequencing.

Current status and challenges in drug discovery against the globally important zoonotic cryptosporidiosis

The zoonotic cryptosporidiosis is globally distributed,one of the major diarrheal diseases in humans and animals.Cryptosporidium oocysts are also one of the major environmental concerns,making it a pathogen that fits well into the One Health concept.Despite its importance,fully effective drugs are not yet available.Anti-cryptosporidial drug discovery has historically faced many unusual challenges attributed to unique parasite biology and technical burdens.While significant progresses have been made recently,anti-cryptosporidial drug discovery still faces a major obstacle:identification of systemic drugs that can be absorbed by patients experiencing watery diarrhea and effectively pass through electron-dense(ED)band at the parasite-host cell interface to act on the epicellular parasite.There may be a need to develop an in vitro assay to effectively screen hits/leads for their capability to cross ED band.In the meantime,non-systemic drugs with strong mucoadhesive properties for extended gastrointestinal exposure may represent another direction in developing anti-cryptosporidial therapeutics.For developing both systemic and non-systemic drugs,a non-ruminant animal model exhibiting diarrheal symptoms suitable for routine evaluation of drug absorption and anti-cryptosporidial efficacy may be very helpful.

Effect of Egyptian propolis on cryptosporidiosis in immunosuppressed rats with special emphasis on oocysts shedding,leukogram,protein profile and ileum histopathology

Objective:To investigate the activity of Egyptian propolis extracts(ethanol and water)on cryptosporidiosis in experimentally infected dexamethasone-immunosuppressed rats.Methods:A total of 180 male rats(190-220)g BWt were randomly divided into 9 equal groups(G1-G9).Groups of rats were kept as(G1):normal control,(G2-G9):immunosuppressed with dexamethasone and(G3-G9):infected with Cryptosporidium oocysts.Rats from(G4to G9)were given orally ethanol and water extract of propolis(at a dose of 50 mg/kg BWt)and nitazoxanide(standard anti-cryptosporidial drug at a dose of 100 mg/kg BWt)to infected rats with different regimes.Faecal pellets were collected from all groups to monitor oocysts shedding from the 2nd to the 15th day post infection.At the end of the experiment,blood was collected from all groups for determination of leukogram and serum proteins.Ileum specimens were also examined histopathologically.Results:The highest reduction of oocysts shedding in faecal samples was 88%in rats prophylactically treated with propolis ethanol extract at the 4th dpi,and in rats prophylactically treated with water extract of propolis,was91%at the 6th dpi.There was a marked increase in neutrophils count and α_2-andβ-globulins levels in infected rats treated with both extracts,while a significant decrease was detected in lymphocytes compared to the infected non treated group.β-globulin level markedly increased in the rats administered nitazoxanide.Histopathological changes were observed in the ileum of rats infected with Cryptosporidium.Conclusions:Egyptian propolis extracts have an activity on cryptosporidiosis in rats.Moreover,propolis modulated the immunity in dexamethasone-immunosuppressed rats.

Hepatic portal venous gas due to cryptosporidiosis in a patient with acquired immunodefi ciency syndrome

Although the presence of hepatic portal venous gas (HPVG) on computed tomography (CT) is typically an ominous finding, HPVG may sometimes be less catastrophic. The clinical significance of HPVG is variable, and it depends primarily on the underlying pathol ogy. We report a case of a patient with acquired immunodeficiency syndrome (AIDS) who was found to have HPVG on CT as a presumed result of gastrointestinal cryp tosporidiosis, an association that, to our knowledge, has not been reported. This case illustrates another cause of HPVG that should be considered in patients with AIDS.

Prevalence of cryptosporidiosis in animals in Iran: A systematic review and meta-analysis

Objective:To review the prevalence of cryptosporidiosis among animal population of Iran.Methods:Data were systematically gathered from 1 January 2000 to 1 January 2020 in the Islamic Republic of Iran from the following electronic databases:Pub Med,Springer,Google Scholar,Science Direct,Scopus,Web of Science,Magiran,and Scientific Information Database(SID).According to the preferred reporting items for systematic reviews and meta-analyses(PRISMA)and inclusion criteria,88 eligible studies were obtained.Results:The pooled prevalence of cryptosporidiosis using random and fixed effects model according to heterogeneity among animals was as follows:rodents 18.8%(95%CI 12.6%-25.0%),camels 17.1%(95%CI 8.6%-25.7%),cattle 16.8%(95%CI 13.4%-20.1%),goats 14.1%(95%CI 5.2%-23.0%),horses 12.2%(95%CI 8.3%-16.2%),birds 10.5%(95%CI 7.6%-13.4%),sheep 9.9%(95%CI 2.4%-4.9%),cats 8.8%(95%CI 4.8%-12.8%)and dogs 3.7%(95%CI 7.0%-12.8%).Conclusions:Cryptosporidiosis has been reported and present in a wide range of animals in Iran over the years and has a high prevalence in most of these species.

Cryptosporidiosis threat under climate change in China:prediction and validation of habitat suitability and outbreak risk for human-derived Cryptosporidium based on ecological niche models

Background Cryptosporidiosis is a zoonotic intestinal infectious disease caused by Cryptosporidium spp.,and its transmission is highly influenced by climate factors.In the present study,the potential spatial distribution of Cryptosporidium in China was predicted based on ecological niche models for cryptosporidiosis epidemic risk warning and prevention and control.Methods The applicability of existing Cryptosporidium presence points in ENM analysis was investigated based on data from monitoring sites in 2011–2019.Cryptosporidium occurrence data for China and neighboring countries were extracted and used to construct the ENMs,namely Maxent,Bioclim,Domain,and Garp.Models were evaluated based on Receiver Operating Characteristic curve,Kappa,and True Skill Statistic coefficients.The best model was constructed using Cryptosporidium data and climate variables during 1986‒2010,and used to analyze the effects of climate factors on Cryptosporidium distribution.The climate variables for the period 2011‒2100 were projected to the simulation results to predict the ecological adaptability and potential distribution of Cryptosporidium in future in China.Results The Maxent model(AUC=0.95,maximum Kappa=0.91,maximum TSS=1.00)fit better than the other three models and was thus considered the best ENM for predicting Cryptosporidium habitat suitability.The major suitable habitats for human-derived Cryptosporidium in China were located in some high-population density areas,especially in the middle and lower reaches of the Yangtze River,the lower reaches of the Yellow River,and the Huai and the Pearl River Basins(cloglog value of habitat suitability>0.9).Under future climate change,non-suitable habitats for Cryptosporidium will shrink,while highly suitable habitats will expand significantly(χ^(2)=76.641,P<0.01;χ^(2)=86.836,P<0.01),and the main changes will likely be concentrated in the northeastern,southwestern,and northwestern regions.Conclusions The Maxent model is applicable in prediction of Cryptosporidium habitat suitability and can achieve excellent simulation results.These results suggest a current high risk of transmission and significant pressure for cryptosporidiosis prevention and control in China.Against a future climate change background,Cryptosporidium may gain more suitable habitats within China.Constructing a national surveillance network could facilitate further elucidation of the epidemiological trends and transmission patterns of cryptosporidiosis,and mitigate the associated epidemic and outbreak risks.

PRELIMINARY STUDY ON CRYPTOSPORIDIOSIS OF CALVES IN SUBURBAN DISTRICT OF BEIJING

Cryptosporidiosis, azoonosis caused by Cryptosporidium spp., is a newly recognized coccidial protozoan infection, which olden induces protracted watery diarrhea and malnutrition in a wide range of vertebrates and man. Its distribution is worldwide. The situation of this infection in China is, however, practically unknown. This note deals with a preliminary survey of Cryptosporidiosis in calves in suburban district of Beijing.

Pathomorphologic Study of Parasitic Enteritis Caused by Acute Canine Distemper

[Objective]The aim was to survey relationship between acute canine distemper and parasitic enteritis from pathology. [Method]Twelve cases of acute canine distemper with diarrhea were researched as per immunohistochemistry,Haematoxylin Eosin,and PAS staining kit. [Result] Of the twelve diseased dogs （ with diarrhea） ,six were detected caused by coccidium and two were detected by cryptosporidium. Coccidian protozoa is mainly in epithelial cells of jejunum and ileum,and some can be found in cut-off intestinal epithelial cells and in mucus formed by destroyed intesti- nal villus. The most common shapes of coccidian protozoa are trophozoite and schizont. The former is mainly within or among epithelial cells; nucle- us is in center and stained by hematoxylin; protoplasm is in ＂ fined mesh＂ shape. The latter,round or oval,contains much glycogenosome in de- generated intestinal epithelial cells. On the other hand,cryptosporidium is mainly in striated borders of intestinal epithelial cells and intestinal gland cells,leading to destruction of villus and cut-off of cells. Through detection on monoclonal antibody of nucleocapsid proteins of anti-canine distemper virus,it was found that epithelial cells in intestinal mucosa,glandular cells in recesses,lymphocytes and macrophage infittrated in lamina propria and dendritic cells in aggregated nodule were all with positive reactions. [Conclusion]Parasitic diarrhea caused by acute canine distemper occurs when resistance of intestinal mucosa caused by canine distemper virus begins to decline.