Genetic characterization and transmission cycles of Cryptosporidium species isolated from humans in New Zealand

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.     

Enteroparasitoses in the V Region, Chile. A study of rural school children from Santo Domingo, 1987]

The results of a new enteroparasitological survey carried out by the authors are analyzed with the aim of contributing to the knowledge of the situation of these infections in the V Region, Chile. In 1987 the children of five rural schools of Santo Domingo were studied by means of the modified Telemann method, the Ziehl-Neelsen stain and seried Graham test. The parasites more frequently found were: E. vermicularis (50.4%) and G. lamblia (10.8%). No E. histolytica was found in these children. The most frequent commensal was E. nana (21.9%). Cryptosporidium sp. presented a low frequency (0.9%), a figure that in these asymptomatic subjects is in accordance with that found in outpatients with chronic diarrhea in Valparaíso, V Region.     

Breast-Feeding Protects Infantile Diarrhea Caused by Intestinal Protozoan Infections

This study investigated the effect of breast-feeding in protection against protozoan infection in infants with persistent diarrhea. Infants were classified into 2 groups; 161 breast-fed infants and the same number of non-breast-fed infants. Microscopic examinations of stool were done for detection of parasites and measuring the intensity of infection. Moreover, serum levels of IgE and TNF-α were measured by ELISA. Cryptosporidium spp., Entamoeba histolytica/Entamoeba dispar, Giardia lamblia, and Blastocystis sp. were demonstrated in infants with persistent diarrhea. The percentage of protozoan infections was significantly lower in breast-fed infants than that in the non-breast-fed infants. The levels of IgE and TNF-α were significantly lower in the breast-fed group than in the non-breast-fed group. There were significant positive associations between the serum levels of IgE and TNF-α and the intensity of parasite infection in the breast-fed group. It is suggested that breast-feeding has an attenuating effect on the rate and intensity of parasite infection.     

Epidemiology and etiology of diarrhea in colony-born Macaca nemestrina

The epidemiology of diarrhea in colony-born M. nemestrina was studied in 205 neonates and infants in an Infant Primate Research Laboratory (IPRL), and in 248 neonates, juveniles and adolescents up to 4 years of age at a separate breeding and holding facility (Primate Field Station, PFS). Computerized medical records of individual animals over a 5-year period were analyzed to determine the incidence of diarrhea; age, duration and number of episodes; mortality and etiology. The incidence of diarrhea at the IPRL was highest in infants at less than 1 month of age (18.6 cases per 1000 animal days) and at 1-6 months olds (2.0 cases per 1000 animals days). Many infants had multiple episodes. All episodes were less than 10 days in duration. Mortality was low. At the PFS, the highest incidence occurred in infants at 6-12 months of age (1.36 cases per 1000 animal days). Multiple episodes were less common. Duration was variable. The infectious agents diagnosed at both facilities were Shigella, Campylobacter and Cryptosporidium. No pathogens were identified in many episodes. Shigella was more common at PFS than at the IPRL. Chronic diarrhea occurred in approximately 10% of animals at PFS. Intestinal amyloidosis and retroperitoneal fibromatosis were found in 13 animals with chronic diarrhea. Further studies are needed to determine the pathogenesis of chronic diarrhea, the etiologic significance of Campylobacter, and the causes of diarrhea when no pathogens are isolated.     

Cryptosporidiosis in patients with colorectal cancer

Parasitological examination of feces was carried out for 55 patients with diagnosed colorectal cancer before chemotherapy. Except for Cryptosporidium sp., no other intestinal parasites were found in the specimens; moreover, only the patients with watery diarrhea were Cryptosporidium sp.-positive by enzyme immunoassay. Prevalence of infection in the group of patients with diarrhea (23 persons) was 43.5%, whereas it was 18% for the entire group of patients under study. Coproantigens of this parasite were detected primarily in the patients with tumors located on the left side (in the sigmoid and descending colon).     

Etiology and Epidemiology of Diarrhea in Hospitalized Children from Low Income Country: A Matched Case-Control Study in Central African Republic

Background

In Sub-Saharan Africa, infectious diarrhea is a major cause of morbidity and mortality. A case-control study was conducted to identify the etiology of diarrhea and to describe its main epidemiologic risk factors among hospitalized children under five years old in Bangui, Central African Republic.

Methods

All consecutive children under five years old hospitalized for diarrhea in the Pediatric Complex of Bangui for whom a parent’s written consent was provided were included. Controls matched by age, sex and neighborhood of residence of each case were included. For both cases and controls, demographic, socio-economic and anthropometric data were recorded. Stool samples were collected to identify enteropathogens at enrollment. Clinical examination data and blood samples were collected only for cases.

Results

A total of 333 cases and 333 controls was recruited between December 2011 and November 2013. The mean age of cases was 12.9 months, and 56% were male. The mean delay between the onset of first symptoms and hospital admission was 3.7 days. Blood was detected in 5% of stool samples from cases. Cases were significantly more severely or moderately malnourished than controls. One of the sought-for pathogens was identified in 78% and 40% of cases and controls, respectively. Most attributable cases of hospitalized diarrhea were due to rotavirus, with an attributable fraction of 39%. Four other pathogens were associated with hospitalized diarrhea: Shigella/EIEC, Cryptosporidium parvum/hominis, astrovirus and norovirus with attributable fraction of 9%, 10%, 7% and 7% respectively. Giardia intestinalis was found in more controls than cases, with a protective fraction of 6%.

Conclusions

Rotavirus, norovirus, astrovirus, Shigella/EIEC, Cryptosporidium parvum/hominis were found to be positively associated with severe diarrhea: while Giardia intestinalis was found negatively associated. Most attributable episodes of severe diarrhea were associated with rotavirus, highlighting the urgent need to introduce the rotavirus vaccine within the CAR’s Expanded Program on Immunization. The development of new medicines, vaccines and rapid diagnostic tests that can be conducted at the bedside should be high priority for low-resource countries.     

Clinical and parasitologic aspects of cryptosporidiosis in nonhuman primates

Eighty-one cases of acute cryptosporidiosis were diagnosed among 157 (52%) infant primates, predominantly Macaca nemestrina, housed in the nursery unit of the Washington Regional Primate Research Center. The mean age at onset of oocyst passage was 38 +/- 25 days. The outbreak was confined to the nursery and no cases were detected among juvenile or adult primates housed in other rooms within the colony. All but one animal manifested symptoms of enteric infection, including severe diarrhea and dehydration. Infected animals excreted oocysts for a mean of 36 days (range 7-78 days). No reinfections occurred. Cryptosporidium was the second most common enteric pathogen detected in the population, after Campylobacter jejuni. The risk of infection was related to the length of time the animal was housed in the nursery and to social interaction with other monkeys. These findings are relevant to the understanding of the epidemiology of cryptosporidiosis among human infants and children in environments with close social interactions and minimal learned personal hygiene practices.     

口服补液盐治疗儿童急性腹泻轻中度脱水的疗效研究

目的:观察口服补液盐治疗儿童急性腹泻轻中度脱水的临床疗效。方法:选取我院儿科收治的63例急性腹泻伴轻中度脱水症状患儿,采取随机数表法分为两组,其中对照组32例患儿予标准口服补液盐,而治疗组31例患儿予补液盐溶液。对比治疗前后两组患儿血浆内Na+、K+、Cl-离子水平,临床症状恢复时间及改善情况。结果:治疗后,两组患儿的电解质水平均有所改善,治疗组患儿Na+、K+及Cl-水平均优于对照组,差异有统计学意义(P0.05);治疗组患儿口渴、头晕、乏力及腹痛症状的恢复时间均较对照组明显缩短,差异有统计学意义(P0.05)。治疗组临床总有效率明显优于对照组,差异具有统计学意义(P0.05)。结论:口服补液盐能明显改善儿童急性腹泻而致的轻中度脱水症状,减少静脉输液对患儿造成的负面影响,值得在临床上进行推广。     

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

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.     

Breast-feeding, diarrhoea and sanitation as components of infant and child health: a study of large scale survey data from Ghana and Nigeria

Using Demographic and Health Survey datasets from Ghana and Nigeria, this study examined whether the protective effects of breast-feeding are greatest where the poorest sanitation conditions prevail. It was found that mixed-fed infants aged between 0 and 11 months tend to have a higher risk of diarrhoea than fully breast-fed children, while the risk of diarrhoea among weaned infants is twice that of mixed-fed infants. The probit regression models employed in the analysis were used to predict the probability of diarrhoea associated with each breast-feeding pattern for both 'poor' and 'good' sanitation areas. It was found that the risk of diarrhoea among mixed-fed infants in the poor sanitation areas tends to be high while the same risk among fully breast-fed infants tends to be minimal. In essence, the health risks of mixed feeding are real, particularly for infants aged less than 7 months, and are even worse for those weaned before 6 months of age.     

凝结芽孢杆菌活菌片预防小儿肺炎继发性腹泻疗效观察

目的观察和评价凝结芽孢杆菌活菌片（商品名：爽舒宝）与抗菌药联用预防小儿肺炎继发性腹泻的临床疗效。方法将164例肺炎患儿随机分为预防组和对照组,预防组84例,对照组80例,两组均给予抗菌药及对症支持治疗。其中预防组在治疗的同时序贯（间隔2～3h）应用凝结芽孢杆菌活菌片,出现腹泻继续服用;对照组单用抗菌药,出现腹泻用凝结芽孢杆菌活菌片治疗。对两组继发性腹泻的发生率、腹泻持续天数、肺炎治疗的总疗程、腹痛和肠鸣音异常等症状和体征进行统计分析。结果预防组继发腹泻10例,发生率11．9％,对照组继发腹泻41例,发生率51．3％,两组相比差异具有统计学意义（P〈0．01）;预防组腹泻持续时间和治疗疗程显著短于对照组（P〈0．05）;预防组患儿腹痛、肠鸣音异常和脱水等症状和体征发生率均少于对照组（P〈0．05）。结论凝结芽孢杆菌活菌片与抗菌药序贯应用治疗肺炎,能显著降低继发性腹泻的发生率,缩短疗程,值得临床推广。     

Cryptosporidiosis in the V Region Chile. III. Study of malnourished patients, 1985-1987

Frequency of infection by Cryptosporidium sp. in 1,039 faecal smears stained by Ziehl-Neelsen, obtained from undernourished patients of a Nutritional Recovery Center and an ambulatory undernourished center from the Fifth Region, Chile, were studied. All underwent a coproparasitological examination by the modified Telemann method. Thirty eight (3.7%) patients infected by the parasite were detected, with an overall frequency of 8.5% among patients of the Nutritional Recovery Center and 1.9% among the ambulatory patients; this difference was statistically significant. The highest percentage of positive results were detected among the younger milk feeding infants. Also the percentage of difference among these and the older milk feeding infants (3.7%) was statistically significant. Association of Cryptosporidium sp. and Giardia lamblia was observed in 6 ambulatory patients (2.3%).     

Breast-feeding promotion in Manitoba. Committee on Breast-feeding,Manitoba Pediatric Society.

During the International Year of the Child the Manitoba Pediatric Society undertook professional and public education activities to promote breast-feeding in that province. The objective was a 100% increase in the proportion of mothers who breast-fed their infants for 2 months or longer. Surveys conducted before and after the campaign showed no significant increase in the rate of breast-feeding either at the time of hospital discharge or 2 months later. The infants of Winnipeg residents were more likely to be breast-fed than those of women living on Indian reservations or in any other part of the province (termed "rural"). The rate of bottle-feeding was significantly greater among infants of young unmarried mothers. Future programs to promote breast-feeding should be longer and more intensive, should be directed to the young, to rural residents and to Indian women, and should focus on social and emotional factors as well as nutrition and health benefits.     

Enteric bifidobacteria: isolation from human infants and challenge studies in mice.

Bifidobacteria from breast-fed infants, formula-fed infants, or premature babies fed by parenteral methods were isolated and identified. The persistence of these microorganisms in the gastrointestinal tract of mice, after oral administration, was studied to determine the optimal dose and frequency of translocation to the liver and spleen. The rate of isolation among infants varied between 19 and 82% depending on the origin of the samples, with the highest values seen in breast-fed babies. The predominant species found in all cases was Bifidobacterium adolescentis. The optimal dose for oral administration of bifidobacteria to mice was 10(7) cells per day per animal for up to 2, 5, or 7 days. These bacteria remained up to 5 days postfeeding, even if feeding was interrupted. The results of bacterial translocation assays showed differences for the different strains and doses tested.     

Prevalence of Cryptosporidium sp. infection in diarrheic and non-diarrheic humans in Iran

For evaluation of the prevalence of Cryptosporidium sp. infection in diarrheic and non-diarrheic humans in Iran, fecal specimens from diarrheic (n = 129) and non-diarrheic humans (n = 271) were collected and examined for the presence of Cryptosporidium sp. oocysts. The presence of Cryptosporidium sp. oocysts was determined by Ziehl- Neelsen acid-fast staining. Humans were grouped according to their age as follows: younger than 15, 16-25, 26-35, 36-50, and over 51 years. The results showed that the overall prevalence of infection in all 400 samples was 10.8%, but the prevalence (25.6%) in diarrheic humans was higher than that (3.7%) in non-diarrheic humans. Oocysts of Cryptosporidium sp. were detected in the feces of 21.4%, 9.3%, 8.8%, 6.7% and 5.7% of different age groups, respectively. The intensity of oocysts was significantly higher in diarrheic humans than in non-diarrheic ones. There was a significant association between Cryptosporidium sp. infection and occurrence of diarrhea (P < 0.05). The results indicate that Cryptosporidium sp. infection is prevalent in diarrheic humans in Iran.     

Intestinal parasites infections in hospitalized AIDS patients in Kinshasa, Democratic Republic of Congo

To determine the prevalence and the species spectrum of intestinal parasites (IP) involved in hospitalized AIDS patients, a prospective observational and cross-sectional study was carried out in the four main hospitals in Kinshasa, Democratic Republic of the Congo. From November 2006 through September 2007, a single stool sample was collected from 175 hospitalized AIDS patients older than 15 years. Parasites were detected by light microscopy, including Ziehl-Neelsen, Fungi-Fluor, modified trichrome stains, and by immunofluorescence antibody tests and PCR for species diagnosis of microsporidia. At baseline, 19 patients (10.8%) were under antiretroviral therapy and 156 (89.2%) were eligible for ART. The main diagnosis for justifying hospitalization was intestinal infection associated with diarrhea in 87 out of 175 (49.7%). 47 out of 175 (26.9%) were found to harbor an IP, and 27 out of 175 (15.4%) were infected with at least one opportunistic IP (OIP). Prevalence rate for OIP were 9.7%, 5.1%, 1.7% and 0.6% for Cryptosporidium sp., Enterocytozoon bieneusi, Isospora belli and Encephalitozoon intestinalis respectively. Considering patients with diarrhea only, prevalence rate were 12.6%, 4.6%, 3.4% and 1.1% respectively. The other IP observed were Entamoeba histolytica/Entamoeba dispar in nine cases (5.1%), Ascoris lumbricoides in seven cases (4.0%), Giardia intestinalis in three cases (1.7%), hookworm in two cases (1.1%) and Trichiuris trichiura, Enterobius vermicularis, Schistosoma mansoni in one patient each (0.6%). No significant relationship was established between any individual IP and diarrhea. These results underline the importance of OIP in symptomatic AIDS patients regardless of diarrhea at the time of the hospitalisation, and showed that routine microscopic examination using stains designed for Cryptosporidium spp. or the microsporidia should be considered due to the absence of clinical markers.     

Incidence of infection by intestinal parasites among school children in Santiago, Chile, 1988-1989

In December 1988-February 1989 period, a survey on enteroparasitic infections in children (mean age 8.7 years; males 54.4% and females 45.6%) from five schools located in Santiago, Chile, was undertaken. To each of these individuals, three samples were obtained in order to perform in them the following examinations: co-proparasitological study, modified Ziehl-Neelsen staining for detecting Cryptosporidium sp. and cellulose adhesive test for Enterobius vermicularis. Parasitic elements were found in the following percentages: Blastocystis hominis 51.8, Enterobius vermicularis 39.9, Giardia lamblia 32.1, Entamoeba histolytica 7.8, Hymenolepis nana 2.1 and Ascaris lumbricoides 0.4, Cryptosporidium sp. were not observed. The present study would be demonstrating that enteroparasites maintain their endemic condition among school children from Santiago, including B. hominis which had not been searched previously.     

Evaluating the Impact of Breastfeeding on Rotavirus Antigenemia and Disease Severity in Indian Children

Objectives

To evaluate the contribution of breastfeeding to Rotavirus (RV)-induced antigenemia and/or RNAemia and disease severity in Indian children (<2 yrs age).

Methods

Paired stool and serum samples were collected from (a) hospitalized infants with diarrhea (n = 145) and (b) healthy control infants without diarrhea (n = 28). Stool RV-antigen was screened in both groups by commercial rapid-test and enzyme immunoassay. The disease severity was scored and real-time-PCR was used for viral-load estimation. Serum was evaluated for RV-antigenemia by EIA and RV-RNAemia by RT-PCR. Data was stratified by age-group and breastfeeding status and compared.

Results

Presence of RV-antigenemia and RV-RNAemia was positively related with presence of RV in stool. Disease severity and stool viral-load was significantly associated with RV-antigenemia[(r = 0.74; CI:0.66 to 0.84; P<0.0001,R² = 0.59) and (r = -0.55; CI:-0.68 to -0.39; P<0.0001,R² = 0.31) respectively], but not with RV-RNAemia. There was significant reduction in RV-antigenemiarate in the breast-fed group compared to non-breastfed infants, especially in 0–6 month age group (P<0.001). Non-breastfed infants were at risk for RV-antigenemia with severe disease manifestations in form of high Vesikari scores correlating with high fever, more vomiting episodes and dehydration.

Conclusion

RV-antigenemia was common in nonbreastfed children with severe RV-diarrhea and correlated with stool RV-load and disease severity.     

Cryptosporidium sp. and Giardia sp. infections in mountain gorillas (Gorilla gorilla beringei) of the Bwindi Impenetrable National Park, Uganda

For conservation purposes and because of growing ecotourism, some mountain gorilla (Gorilla gorilla beringei) populations have been habituated to humans. Fecal specimens (n = 100) of nonhabituated and human-habituated gorillas (5 populations; 6 age classes) were tested for Cryptosporidium sp. oocysts and Giardia sp. cysts by conventional staining and immunofluorescent antibody (IFA). Cryptosporidium sp. infections (prevalence 11%) were not restricted to very young gorillas but were observed in 3-yr-old to >12-yr-old gorillas; most of the infections (73%) occurred in human-habituated gorillas. The prevalence of Giardia sp. infections was 2%; 1 nonhabituated gorilla was concomitantly infected. Oocysts of Cryptosporidium sp. in the gorilla stools were morphologically, morphometrically, and immunologically undistinguishable from a bovine isolate of Cryptosporidium parvum oocysts. Mean concentration of Cryptosporidium sp. oocysts and Giardia sp. cysts in gorilla stools was 9.39x10(4)/g, and 2.49x10(4)/g, respectively. There was no apparent relationship between oocyst concentration and gorilla age, sex, or habituation status. Most Cryptosporidium sp. infections found in gorillas with closest proximity to people may be a result of the habituation process and ecotourism. This study constitutes the first report of Cryptosporidium sp. infections in the family Pongidae, in the free-ranging great apes, and in the species of gorilla.