Epidemiology of Cryptosporidiosis, New York City, New York, USA, 1995-20181.

Cryptosporidiosis is a parasitic diarrheal infection that is transmitted by the fecal-oral route. We assessed trends in incidence and demographic characteristics for the 3,984 cases diagnosed during 1995-2018 in New York City, New York, USA, and reported to the New York City Department of Health and Mental Hygiene. Reported cryptosporidiosis incidence decreased with HIV/AIDS treatment rollout in the mid-1990s, but the introduction of syndromic multiplex diagnostic panels in 2015 led to a major increase in incidence and to a shift in the demographic profile of reported patients. Incidence was highest among men 20-59 years of age, who consistently represented most (54%) reported patients. In addition, 30% of interviewed patients reported recent international travel. The burden of cryptosporidiosis in New York City is probably highest among men who have sex with men. Prevention messaging is warranted for men who have sex with men and their healthcare providers, as well as for international travelers.

Comparison of three cryptosporidiosis outbreaks in Western Australia: 2003, 2007 and 2011.

Cryptosporidium is a protozoan parasite that causes the diarrhoeal disease, cryptosporidiosis. Although many species have been identified, the majority of human disease worldwide is caused by two species; Cryptosporidium parvum and Cryptosporidium hominis. In Australia, data from the National Notifiable Diseases Surveillance System (NNDSS) show that cryptosporidiosis outbreaks occur every few years. To better understand the transmission, trends and nature of cryptosporidiosis outbreaks in Western Australia, epidemiological and genomic data from three cryptosporidiosis outbreaks in 2003, 2007 and 2011 were reviewed. The 2007 outbreak was the largest (n = 607) compared with the outbreaks in 2003 (n = 404) and 2011 (n = 355). All three outbreaks appeared to have occurred predominantly in the urban metropolitan area (Perth), which reported the highest number of case notifications; increases in case notifications were also observed in rural and remote areas. Children aged 0-4 years and non-Aboriginal people comprised the majority of notifications in all outbreaks. However, in the 2003 and 2007 outbreaks, a higher proportion of cases from Aboriginal people was observed in the remote areas. Molecular data were only available for the 2007 (n = 126) and 2011 (n = 42) outbreaks, with C. hominis the main species identified in both outbreaks. Subtyping at the glycoprotein 60 (gp60) locus identified subtype IbA10G2 in 46.3% and 89.5% of C. hominis isolates typed, respectively, in the 2007 and 2011 outbreaks, with the IdA15G1 subtype was identified in 33.3% of C. hominis isolates typed in the 2007 outbreak. The clustering of cases with the IdA15G1 subtype in the remote areas suggests the occurrence of a concurrent outbreak in remote areas during the 2007 outbreak, which primarily affected Aboriginal people. Both the C. hominis IbA10G2 and IdA15G1 subtypes have been implicated in cryptosporidiosis outbreaks worldwide; its occurrence indicates that the mode of transmission in both the 2007 and 2011 outbreaks was anthroponotic. To better understand the epidemiology, sources and transmission of cryptosporidiosis in Australia, genotyping data should routinely be incorporated into national surveillance programmes.

Differences in the occurrence and epidemiology of cryptosporidiosis in Aboriginal and non-Aboriginal people in Western Australia (2002-2012).

Cryptosporidiosis is a diarrhoeal illness caused by the protozoan parasite Cryptosporidium. In Australia, very little is known about the epidemiology of cryptosporidiosis in Aboriginal peoples. The present study analysed long-term cryptosporidiosis patterns across Western Australia (WA) (2001-2012), combined with genotyping and subtyping data at the 18S and glycoprotein 60 (gp60) loci respectively. Comparison of cryptosporidiosis notifications between Aboriginal and non-Aboriginal people in WA, revealed that notification rates among Aboriginal people were up to 50 times higher compared to non-Aboriginal people, highlighting the burden of the disease in this population. More than 90% of notifications were in Aboriginal children aged 00-04years, who had a notification rate 20.5 times higher than non-Aboriginal children in the same age group. Cryptosporidium hominis was the predominant species infecting both Aboriginal and non-Aboriginal people. However, Aboriginal people were mainly infected with the C. hominis IdA15G1 subtype, whereas non-Aboriginal people were predominantly infected with the IbA10G2 subtype. To control cryptosporidiosis in Aboriginal populations in Australia, effective health interventions/promotions need to be a priority for public health research and action.

A retrospective review of notified human cryptosporidiosis cases in the Waikato region of New Zealand, 2004 to 2011.

AIM: To retrospectively review notified human cryptosporidiosis cases in the Waikato region of New Zealand between 2004 and 2011 and to identify risk factors for human cryptosporidiosis infection. METHOD: Waikato cryptosporidiosis notification data for the period 1 January 2004 to 31 December 2011 were analysed to identify any trends in the rates and distribution of key variables. A comparison was made between urban and rural dwelling cases. RESULTS: Annual Waikato cryptosporidiosis notification rates were consistently higher than national rates. Analysis showed a seasonal peak centred around September with most cases having direct or indirect contact with cattle. Comparisons between urban and rural cases showed similar probable causes of infection and higher rates of infection in rural cases. CONCLUSION: Those who have contact with animals continue to be at risk of infection from Cryptosporidium. The data suggests that children who live on rural properties and have contact with animal faeces, either directly or via a contaminated drinking water supply, are at the highest risk of infection.

Childhood Cryptosporidium infection among aboriginal communities in Peninsular Malaysia.

Cryptosporidium is a coccidian parasite that is prevalent worldwide, some species of which cause morbidity in both immunocompromised and immunocompetent individuals. The prevalence and predictors of Cryptosporidium infection, and its effect on nutritional status, have recently been explored among 276 children (141 boys and 135 girls, aged 2-15 years) in aboriginal (Orang Asli) villages in the Malaysian state of Selangor. Faecal smears were examined by the modified Ziehl-Neelsen staining technique while socio-economic data were collected using a standardized questionnaire. Nutritional status was assessed by anthropometric measurements. Cryptosporidium infection, which was detected in 7.2% of the aboriginal children, was found to be significantly associated with low birthweight (≤2.5 kg), being part of a large household (with more than seven members) and prolonged breast feeding (>2 years). The output of a binary logistic regression confirmed that large household size was a significant predictor of Cryptosporidium infection (giving an odds ratio of 2.15, with a 95% confidence interval of 1.25-5.02). Cryptosporidium infection is clearly a public-health problem among the aboriginal children of Selangor, with person-to-person the most likely mode of transmission.

Prevalence of Cryptosporidium spp. in children with diarrhoea in the West Bank, Palestine.

This study was conducted to investigate the prevalence of Cryptosporidium spp. in children (n=760) with diarrhea aged 1 month to 13 years, living in urban areas (n=234), rural areas (n=394) and refugee camps (n=132). Samples were collected, stained by modified acid fast stain, and examined microscopically for oocysts. The overall prevalence was 11.6% (88/760). The prevalence was higher in refugee camps at 12.9% (17/132) and in rural areas at 12.2% (48/394) as compared to 9.8% (23/234) in urban areas. According to age, the prevalence in age group I (<5 years) was significantly high (P<0.05) at 14.4% (67/464) as compared to 7.7% (15/195) in age group II (5-10 years) and 5.9% (6/101) in age group III (10-15 years). Our findings indicate that the prevalence of Cryptosporidium spp. is high when compared to that in developed countries.

Analysis of serological responses to Cryptosporidium antigen among NHANES III participants.

PURPOSE: Sera from 1356 National Health and Nutrition Examination Survey (NHANES) III participants from seven primary sampling units were tested for serological responses to two Cryptosporidium antigen groups. Intensity of responses was compared by geographic area, age, sex, race/ethnicity, income, and hepatitis A seropositivity. METHODS: Cryptosporidium seropositivity for the 15/17-kDa and the 27-kDa antigen groups were defined by the intensity of the responses. Conditional and unconditional logistic regression was used to identify significant risk factors. RESULTS: Hispanics, blacks, and females had a higher seropositivity. Younger participants and those with higher income had a lower seropositivity. Being hepatitis A seropositive was strongly related to a weak serological response to the 27-kDa antigen group. Family size was unrelated to Cryptosporidium seropositivity. Significantly higher Cryptosporidium seropositivity was observed for three of the seven primary sampling units. CONCLUSIONS: This study found significant geographical differences in the occurrence and the intensity of serological response. Strong serological responses to the 15/17-kDa antigen occurred more commonly in blacks and Hispanics, individuals not having high incomes, and in older age groups.

Analysis of the spatial distribution of cryptosporidiosis in AIDS patients in San Francisco using density equalizing map projections (DEMP).

Environmental transmission of cryptosporidiosis has occurred repeatedly in defined spatial areas during outbreaks of disease attributed, for example, to drinking water contamination. Little work has been done to investigate the possibility of cryptosporidiosis infection in defined spatial areas in non-outbreak (i.e., endemic) settings. This study applies a novel approach to the investigation of the spatial distribution of cryptosporidiosis in AIDS patients in San Francisco. Density equalizing map projection (DEMP) maps were created for nine race/ethnicity-age groups of AIDS patients based on census tract of residence. Additionally, census tracts with a "high density" of cryptosporidiosis cases were identified by applying smoothing techniques to the DEMP maps, and included as a covariate in multivariate Poisson regression analyses of other known risk factors for cryptosporidios. These analyses suggest: (1) cases of cryptosporidiosis among Black and Hispanic AIDS patients, but not among Whites, show a statistically significant non-random spatial distribution (p < 0.05) even after adjustment for the underlying spatial distribution of AIDS patients for these demographic groups, and (2) the risk of residence in these high density census tracts, adjusted for other known risk factors, was not statistically significant (relative risk = 1.27, 95% confidence interval 0.15, 10.53). These results do not support an independent effect of spatial distribution on the transmission of cryptosporidiosis among AIDS patients.

Cryptosporidium infection in Bedouin infants assessed by prospective evaluation of anticryptosporidial antibodies and stool examination.

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.

Race/ethnicity and other risk of factors associated with cryptosporidiosis as an initial AIDS-defining condition in California, 1980-99.

To study whether African-Americans are less likely than whites to present with cryptosporidiosis as an AIDS-defining condition (ADC), a case-control study was conducted using a large, population-based surveillance registry of AIDS patients in California. Data from January 1980 through June 1999 were analysed using risk factor stratification and multivariate logistic regression to evaluate confounding by other risk factors such as gender, injection drug use (IDU), CD4 counts, age and sexual orientation. Cases included 1373 subjects with cryptosporidiosis as an ADC and controls included 97,419 subjects with other ADC. The results indicate a significantly lower risk for presentation with cryptosporidiosis as an ADC among African-Americans compared with whites (OR vs. whites = 0.5, 95% CI 0.4, 0.7). Additionally, there is evidence that heterosexuals are less likely than homosexual/bisexual males to present with cryptosporidiosis (OR = 0.5, 95% CI 0.4, 0.7). Our analyses also suggest a decreasing risk with increasing age. The possibility that there may be biologic factors or differential lifetime exposures that account for the difference between the racial/ethnic groups merits further investigation.

Cryptosporidiosis in black South African children.

The incidence of cryptosporidiosis in young children was determined by staining of faecal specimens with a modified Kinyoun stain. Seventeen of 92 (18,4%) children with diarrhoea and 1 of 29 (3.4%) controls excreted Cryptosporidium oocysts, suggesting that this was an important enteric pathogen in these children.

Do regional variations in prevalence of cryptosporidiosis occur? The central Ohio experience.

We screened 2,780 consecutive stool specimens submitted for routine ova and parasite examination to assess the prevalence of cryptosporidiosis in a pediatric patient population in central Ohio. The stools were prepared by formalin-ethyl acetate concentration followed by cold Kinyoun acid-fast stain of the sediment. In addition, 912 consecutive intestinal biopsies were monitored for the presence of the parasite. Cryptosporidium oocysts were found in only 0.3 per cent of stool specimens (seven specimens from three patients) and in none of the intestinal biopsies. Due to this low prevalence of cryptosporidiosis, we conclude that routine screening of stool specimens for Cryptosporidium sp. is unnecessary in our patient population. Screening should be targeted to immune compromised patients and patients with persistent diarrhea and no apparent etiology. Our study also supports the concept that there are geographic variations in the prevalence of cryptosporidiosis.