Toxoplasmosis Prevention and Testing in Pregnancy,Survey of Obstetrician–Gynaecologists

Toxoplasmosis in pregnant women can lead to congenital disease with severe neurological and ocular complications in the foetus. In 2006, we surveyed US obstetrician–gynaecologists to determine their knowledge and practices about toxoplasmosis prevention and testing. Questionnaires were mailed (four mailings) to a random sample of 1200 of the 33 354 members of the American College of Obstetricians and Gynecologists (ACOG). Of the 1200 surveyed, 502 (42%) responded. The respondents were similar to all ACOG members by gender, region of the country and practice type (P > 0.5), and age (respondents were slightly younger, mean 46 years versus 47 years). To prevent toxoplasmosis, most respondents indicated that they counsel pregnant women about cat litter (99.6%), but fewer counselled about eating undercooked meat (77.6%), handling raw meat (67.4%), gardening (65.4%) or washing fruits and vegetables (34.2%). Many (73.2%) respondents were not aware that some Toxoplasma IgM tests have had a high false positive rate, and most (91.2%) had not heard of the avidity test, which can help determine the timing of Toxoplasma gondii infection in relation to pregnancy. There is a need for more education about T. gondii serological testing, particularly the Toxoplasma avidity test. US obstetrician–gynaecologists are providing beneficial counselling to their patients, but could provide more information about undercooked meat and soil risks.     

Paediatrician and Caregiver Awareness of Cryptosporidiosis and Giardiasis in Children: US Survey Responses

There appears to be no published information concerning the awareness and knowledge about diarrhoea caused by Cryptosporidium spp. or Giardia lamblia among US paediatricians and caregivers of young children. Two concurrent, separate surveys were conducted among paediatricians and caregivers (~1000 respondents in each survey) of children ages 1–12 years concerning their knowledge, perceptions and attitudes in the diagnosis and treatment of parasitic diarrhoea. Awareness of parasite‐induced diarrhoea was low for specific aspects among both paediatricians and caregivers. Educational efforts to improve awareness on the appropriate clinical presentation, management and treatment of cryptosporidiosis and giardiasis in children with persistent diarrhoea should be undertaken.     

Sushi in Pregnancy,Parasitic Diseases – Obstetrician Survey

Parasites from raw fish can lead to a wide range of clinical manifestations and can be challenging to treat in pregnancy as result of medication exposure of the foetus. We surveyed obstetrician‐gynecologists (ob‐gyns) in the U.S. to determine their knowledge about the consumption of raw fish during pregnancy. In March 2007, a questionnaire was mailed to members of the American College of Obstetricians and Gynecologists (ACOG) randomly selected to represent all members. Non‐responding physicians were sent two additional mailings. Of the 606 ACOG members surveyed, 305 (50%) responded. Most (82%) respondents indicated that eating raw fish is not safe during pregnancy. However, few (19%) knew that thorough freezing kills parasites in fish. Nearly all (94%) respondents thought that parasitic infections can be more challenging to treat in pregnancy. U.S. ob‐gyns believe that eating raw fish during pregnancy is not safe; most would benefit from information about how to prevent infection and about treatment.     

Genetic Characterization of Cryptosporidium spp. in Diarrhoeic Children from Four Provinces in South Africa

The diversity of Cryptosporidium at species, subtype family and subtype level in diarrhoeic children was investigated in four provinces in South Africa. A total of 442 stool samples from children <5 years of age were collected under a large rotavirus surveillance programme and analysed by Ziehl–Neelsen acid‐fast staining. Fifty‐four (12.2%) were positive for Cryptosporidium, of which 25 were genotyped by polymerase chain reaction (PCR)–restriction fragment length polymorphism (RFLP) and DNA sequence analyses of the 18S rRNA gene. The majority of genotyped specimens were identified as C. hominis (76%), and a high genetic diversity was found with five different C. hominis subtype families (Ia, Ib, Id, Ie and If). Cryptosporidium parvum was found in 20% of the isolates, and three subtype families were identified (IIc, IIe and IIb), with subtype family IIc being the most common. One specimen was identified as C. meleagridis of the subtype family IIId. These results are in accordance with findings from other developing countries and report for the first time the presence in South Africa of C. meleagridis, various subtypes of C. parvum and the subtype family Ie of C. hominis. The results suggest that C. hominis and anthroponotic C. parvum subtypes are the major cause of cryptosporidiosis in South Africa. Further molecular studies are needed to better understand the epidemiology and public health importance of Cryptosporidium in humans in South Africa.     

Characterizing the Role of Animal Exposures in Cryptosporidiosis and Shiga Toxin‐producing Escherichia coli Infections: South Dakota, 2012

Cryptosporidium spp. and Shiga toxin‐producing Escherichia coli strains (STEC) are important causes of human illness. Incidence rates of these illnesses are high in South Dakota compared to the USA as a whole. Direct animal contact has been identified as a possible route of exposure for these illnesses. Ruminant animals may carry STEC subclinically, while young ruminants are common sources of zoonotic strains of Cryptosporidium. South Dakota patients with either STEC or cryptosporidiosis during 2012 were interviewed regarding seven categories of animal exposure: (i) petting zoo/fair attendance, (ii) animal event/rodeo attendance, (iii) feed/pet store visits, (iv) farm visits, (v) employment or residence at a farm, (vi) residence with pets and (vii) visiting other households with pets. Of the 50 STEC cases, 78.0% reported animal exposure prior to illness onset, with 23.3% having lived or worked on a farm. Farm visitors in particular had high degrees of animal contact and infrequently practiced personal protective measures. Of the 115 cryptosporidiosis cases, 87.8% reported animal exposures, with 45.6% having lived or worked on a farm and 29.0% having visited a farm prior to illness. Cases with farm exposures reported a high degree of direct animal contact and inconsistent use of personal protective measures. Cryptosporidiosis patients were significantly more likely than STEC patients to have lived or worked on a farm prior to their illness and were older on average. Patients with these illnesses had high rates of animal contact prior to illness. Animal contact on farms emerged as an important exposure route. Educational messages about personal protective measures should be directed at these individuals.     

Pathology of cryptosporidiosis in raccoons: case series and retrospective analysis, 1990–2019

Cryptosporidiosis is an intestinal protozoal disease of public health importance caused by Cryptosporidium spp. Despite the high synanthropism of raccoons, studies describing the pathology of Cryptosporidium spp. infections in this species are lacking. Therefore, we characterized the pathology of cryptosporidiosis in 2 juvenile raccoons. In addition, we conducted a retrospective search of the database of the California Animal Health and Food Safety laboratory for 1990–2019 and found 6 additional cases of cryptosporidiosis in raccoons. Sequencing of cryptosporidia was performed in one autopsied raccoon, and PCR on formalin-fixed, paraffin-embedded tissues in archived cases. The Cryptosporidium skunk genotype (CSkG), a strain of zoonotic relevance, was detected in 6 of 8 cases (75%). Frequently, cryptosporidiosis was associated with enteritis, eosinophilic infiltrates, villus atrophy or blunting and/or fusion, and crypt abscesses or necrosis. In 7 of the 8 cases, there was confirmed concurrent coinfection with canine distemper virus; 1 case was coinfected with canine parvovirus. Although crypt necrosis is considered a classic lesion of canine parvoviral infection in mesocarnivores and not a hallmark of cryptosporidiosis, results suggest that canine distemper virus is capable of mimicking such lesions in combination with cryptosporidia and immunosuppression.     

Knowledge and prevention of tickborne diseases among Hispanic and non‐Hispanic residents of Maryland and Virginia

Tickborne diseases (TBDs) such as Lyme disease (LD), babesiosis, ehrlichiosis and Rocky Mountain spotted fever cause substantial morbidity and even mortality in the USA. Data indicate that Hispanic populations may be at greater risk for occupational exposure to ticks and disseminated LD; however, information on knowledge and practices of Hispanic populations regarding TBDs is limited. We surveyed 153 Hispanic and 153 non‐Hispanic residents of Maryland and Virginia to assess awareness of TBDs, prevention practices and risk of tick encounters. Hispanic respondents were less likely than non‐Hispanics to report familiarity with LD symptoms (21% vs. 53%, p < 0.001) and correctly identify ticks as vectors of LD (40% vs. 85%, p < 0.001). Although there was no significant difference in overall proportion of respondents who routinely take one or more preventive measures to prevent tick bites (59% vs. 61%, p = 0.65), Hispanics were more likely to report showering after coming indoors (36% vs. 25%, p = 0.04) but less likely to conduct daily tick checks compared with non‐Hispanics (17% vs. 35%, p < 0.001). History of tick bite or finding a tick crawling on oneself or a household member in the past year did not significantly differ between Hispanics and non‐Hispanics (19% vs. 24%, p = 0.26). Notably, after controlling for Hispanic/non‐Hispanic ethnicity, primary language (English vs. Spanish) was a significant predictor of whether an individual had knowledge of LD symptoms, correctly identified ticks as vectors for LD and performed daily tick checks. These results provide guidance for future development of more targeted and effective TBD prevention education for both Hispanic and non‐Hispanic communities.     

Cryptosporidium Recovered from Musca domestica,Musca sorbens and Mango Juice Accessed by Synanthropic Flies in Bahirdar,Ethiopia

The study was conducted to determine the role of house flies, Musca domestica and Musca sorbens to carry Cryptosporidium species in natural environment and filth flies potential for contamination of food item they visited using acid‐fast stain technique. Cryptosporidium was identified from flies collected in dairy cow barns, butchery, market and defecating grounds. Musca domestica captured from dairy cow barns and M. sorbens from defecating ground were found carrying more oocyst of Cryptosporidium parvum. Oocyst load per fly for M. domestica and M. sorbens was 5.84 and 3.42, respectively. Flies’ population dynamics in each month had little relation to the monthly oocyst frequency, r = 0.06 and 0.02 for M. domestica and M. sorbens, respectively. Cryptosporidium species oocysts were isolated from frozen mango juice, which filth flies visited in dairy farm barn. Load of oocysts in the mango juice was dependent on time contact of flies with mango juice and more oocysts were recovered (P < 0.05) in mango juice samples accessed by filth flies for longer period. Role of filth flies to carry and deposit Cryptosporidium species oocyst for development of food‐borne cryptosporidiosis is signified.     

Cryptosporidium hominis Subtypes and Enterocytozoon bieneusi Genotypes in HIV‐Infected Persons in Ibadan,Nigeria

Cryptosporidium and Enterocytozoon are common opportunistic pathogens in HIV+ patients in developing countries, especially those do not have access to antiretroviral therapy. To determine the distribution of genotypes/subtypes of Cryptosporidium and Enterocytozoon bieneusi, faecal specimens were collected from 132 HIV+ persons attending a tertiary hospital in Ibadan, Nigeria. By polymerase chain reaction, eight and ten patients were identified as positive for Cryptosporidium spp. and E. bieneusi, respectively. Seven of the Cryptosporidium specimens were identified as C. hominis, while the remaining one as the new species C. viatorum recently identified in the United Kingdom. DNA sequencing of the 60‐kDa glycoprotein gene showed that the C. hominis belonged to three common subtype families: Ia (in three patients), Ib (in one patient) and Ie (in one patient). In contrast, DNA sequencing of the E. bieneusi internal transcribed spacer products showed the occurrence of genotypes associated with both humans (Peru 8 in one patient, Nig2 in two patients and a new genotype in one patient) and animals (D in one patient and Type IV in five patients). Low CD4+ cell count was identified as a risk factor for both cryptosporidiosis and microsporidiosis.     

Investigation of Cryptosporidium spp. and Giardia spp. in a Public Water‐Treatment System

The objective of this study was to investigate the occurrence of Cryptosporidium spp. and Giardia spp. in a public water‐treatment system and to relate the results to physical, chemical, bacteriological and climate parameters. From March to September 2006, 30 samples, 15 of raw water and 15 of treated water, were examined by membrane filtration and direct immunofluorescence (Merifluor). For each sample, a volume of 1000 l was collected. Of the raw‐water samples, 26.6% were positive for Cryptosporidium (mean concentration of 0.15 oocysts/l), and 6.66% were positive for Giardia (concentration of 0.2 cysts/l); 13.33% of the samples were positive for both (mean concentrations of 0.06 oocysts/l and 0.026 cysts/l respectively). All the samples of treated water were negative. There was no correlation (P < 0.05) between the presence of protozoans in the raw water and the parameters measured. The finding of Giardia and Cryptosporidium in raw water indicates that the water sources are contaminated. Considering that giardiasis is prevalent in the population and that Cryptosporidium has recognized zoonotic potential, long‐term monitoring at critical points of the system is necessary to guarantee that the water will not be a vehicle for transmission of these protozoans.     

The prevalence of <Emphasis Type="Italic">Cryptosporidium</Emphasis> species in diarrhoeic lambs in Kars province and potential risk factors

This study was carried out to determine the prevalence of Cryptosporidium species in diarrhoeic lambs and investigate some risk factors in Kars province (Northeastern region of Anatolia) in Turkey. Four hundred faecal samples were taken from the rectums of clinically diarrhoeic and aged to 1-month-old lambs from 34 sheep farms in 20 villages in March-April 2007 and examined by using the modified acid-fast staining technique. The prevalence of Cryptosporidium species was found as 38.8% (155/400). Cryptosporidium oocysts were detected in 90.0% (18/20) of villages and in 76.5% (26/34) of the sheep farms. Infection rates were detected as: 44.4% (67/151) in 1-week-old lambs, 37.5% (39/104) in 2-week-old lambs, 40.0% (38/95) in 3-week-old lambs, and 22.0% (11/50) in 4-week-old lambs. Farms classified according to their zoohygienic conditions and fine, average and bad conditioned farms were contaminated with Cryptosporidium with the percentages of 14.7%, 20.6% and 41.2%, respectively. Clinical cryptosporidiosis was determined in 35.0% of the villages (7/20) and in 29.4% of the sheep farms (10/34), Cryptosporidium oocysts were found in 81.3% of the lambs (91/112) in these farms. Cryptosporidiosis may be a major epidemiological significance in lambs in Kars province, and suggests that naturally infected lambs may be reservoirs of Cryptosporidiosis infections for calves even for humans too.     

Pharmacokinetics of a low dose and FDA‐labeled dose of diclazuril administered orally as a pelleted topdressing in adult horses

The purpose of this study was to determine the pharmacokinetics of the FDA‐approved labeled dose of diclazuril and compare it to a low dose in plasma and CSF in adult horses. During each research period, six healthy adult horses received 0.5 mg/kg of 1.56% diclazuril pellets (Protazil^TM, Merck Animal Health) compared to the approved labeled dose of 1 mg/kg orally once in two separate phases. A dose of 0.5 mg/kg was calculated to each horse's weight. Blood was then collected immediately before diclazuril administration and then at regular intervals up to a 168 h. After the last blood collection following the single dose at hour 168, a once daily oral dose was administered for the next 10 days to ensure the drug's concentration reached steady‐state. To determine the CSF concentration at steady‐state, CSF samples were collected after the 9th oral dose. Blood was then collected after the 10th dose and then at regular intervals up to 168 h. A washout period of 4 weeks was allowed before repeating this protocol for the FDA‐labeled dose at 1 mg/kg. Plasma and CSF samples were analyzed by high‐pressure liquid chromatography. A one‐compartment pharmacokinetic model with first‐order oral absorption was fitted to the single administration data. Steady‐state pharmacokinetics was performed using noncompartmental analysis for steady‐state analysis. The mean (standard deviation) concentration of diclazuril in CSF following the low dose was 26 ng/mL (5 ng/mL), while CSF in the FDA‐labeled dose was 25 ng/mL (4 ng/mL), P = 0.3750. Substantial accumulation in plasma occurred at steady‐state after the 10th dose for both doses. The results of this study show that diclazuril pellets given at the approved label dose and a lower dose both produce similar plasma drug concentrations at steady‐state and attain plasma and CSF concentrations known to inhibit Sarcocystis neurona in cell culture.     

Prevalence and genetic characterization of Giardia spp. and Cryptosporidium spp. in dogs in Iqaluit,Nunavut, Canada

There are few epidemiologic studies on the role of dogs in zoonotic parasitic transmission in the Circumpolar North. The objectives of this study were to: (a) estimate the faecal prevalence of Giardia spp. and Cryptosporidium spp. in dogs; (b) investigate potential associations between the type of dog population and the faecal presence of Giardia spp. and Cryptosporidium spp.; and (c) describe the molecular characteristics of Giardia spp. and Cryptosporidium spp. in dogs in Iqaluit, Nunavut. We conducted two cross‐sectional studies in July and September 2016. In July, the team collected daily faecal samples for 3 days from each of 20 sled dogs. In September, the team collected three faecal samples from each of 59 sled dogs, 111 samples from shelter dogs and 104 from community dogs. We analysed faecal samples for the presence of Giardia spp. and Cryptosporidium spp. using rapid immunoassay and flotation techniques. Polymerase chain reaction (PCR) and sequencing of target genes were performed on positive faecal samples. Overall, the faecal prevalence of at least one of the target parasites, when one faecal sample was chosen at random for all dogs, was 8.16% (CI: 5.52–11.92), and for Giardia spp. and Cryptosporidium spp., prevalence was 4.42% (CI: 2.58–7.49) and 6.12% (CI: 3.88–9.53), respectively. The odds of faecal Giardia spp. in sled dogs were significantly higher than those in shelter and community dogs (OR 10.19 [CI: 1.16–89.35]). Sequence analysis revealed that 6 faecal samples were Giardia intestinalis, zoonotic assemblage B (n = 2) and species‐specific assemblages D (n = 3) and E (n = 1), and five faecal samples were Cryptosporidium canis. Giardia intestinalis is zoonotic; however, Cryptosporidium canis is rare in humans and, when present, usually occurs in immunosuppressed individuals. Dogs may be a potential source of zoonotic Giardia intestinalis assemblage B infections in residents in Iqaluit, Nunavut, Canada; however, the direction of transmission is unclear.     

Investigation of the Role of Companion Animals in the Zoonotic Transmission of Cryptosporidiosis

Companion animals owned by human patients with cryptosporidiosis (cases) and those animals owned by the wider human population (controls), were studied to determine whether Cryptosporidium was more likely to be excreted by case animals than controls. A total of 280 recently voided faecal samples (114 case animals and 166 control animals) were collected and tested by immunomagnetic separation and immunofluorescent microscopy. A multivariable model was also created to identify pet characteristics, contacts and management factors associated with Cryptosporidium infection in animals, using information collected by a standardized questionnaire. The model was designed to take into account the clustering of samples at the owner level and whether the sampled animal was a case or control.     

A study of neonatal cryptosporidosis of foals in New Zealand

Abstract

AIM: To assess the occurrence of Cryptosporidium oocysts in faecal specimens from foals, and investigate an outbreak of neonatal cryptosporidiosis in foals revealed in the course of the study.

METHODS: Faecal specimens from foals received by a diagnostic veterinary laboratory in New Zealand between 2006 and 2007 were submitted to Massey University and tested microscopically for the presence of Cryptosporidium oocysts. The Cryptosporidium isolates in the oocyst-positive specimens were genetically identified to species level. In addition, specimen submission data from the participating laboratory for 2005–2007 were examined. In the course of the study, the identification of one Cryptosporidium-positive specimen triggered an on-farm investigation.

RESULTS: Twelve faecal specimens submitted by the participating laboratory between 2006 and 2007 were tested further, and three were positive for C. parvum. Specimen submission records indicated a total of 67 faecal specimens were tested for Cryptosporidium by the participating laboratory between 2005 and 2007; 12 (18%) were positive. The on-farm investigation on a broodmare farm revealed a high incidence of neonatal diarrhoea in foals; C. parvum was the only enteropathogen found in the faeces of 4/4 affected foals examined. The diarrhoea in all those foals was self-limiting, manifesting during the second week of life, resembling foal heat diarrhoea, and accompanied by a short but intense period of shedding oocysts.

CONCLUSIONS AND CLINICAL RELEVANCE: The fact that Cryptosporidium parasites were identified in 18% of faecal specimens from foals analysed for this agent in 2005–2007 by the participating laboratory indicated that infection with this agent in foals is not uncommon.

Collectively, the results of this and previous studies performed in New Zealand indicate C. parvum is a cause of diarrhoea in newborn foals, potentially accounting for a proportion of cases empirically diagnosed as foal heat diarrhoea. It is therefore advisable to take precautions when handling diarrhoeic foals, until this potentially zoonotic agent is ruled out in the laboratory.     

Prevalence of Cryptosporidium species isolated from HIV/AIDS patients in southwest of Iran

This study aimed to determine the prevalence and species of Cryptosporidium among HIV/AIDS patients in southwest of Iran. Two hundred fifty faecal samples from HIV patients were examined for the presence of Cryptosporidium oocysts using a conventional coproscopic approach. Such oocysts were detected in 18 (7.2%) out of 250 faecal samples. Genomic DNAs from 250 samples were then subjected to a nested-PCR-RFLP technique targeting different loci of 18S rRNA gene for species identification. Out of 250 samples, 27 (10.8%) were positive for different Cryptosporidium spp; Restriction patterns resulting from the digestion of the nested amplicon with restriction endonucleases VspI and SspI showed that C. parvum (70.38%) was the most prevalent species, followed by C. hominis (25.92%) and C. meleagridis (3.7%), respectively. The mean CD4+ T-cell count was 215 cells/μL. There was a strong association between cryptosporidiosis and CD4+ T-cell count (P = 0.000) with the highest prevalence recorded among patients with CD4+ T-cell count < 200 cells/μL. This confirms that there is a low opportunity for this parasite to get established as the patients CD4+ T-cell count increases. Also HIV infection increased the risk of having Cryptosporidium. Our epidemiological findings are useful for any preventive intervention to control disease diffusion.     

Pharmacokinetics of oral chlortetracycline in nonpregnant adult ewes

The objectives of this study were to determine plasma concentrations and pharmacokinetic parameters of feed‐grade chlortetracycline (CTC) in sheep after oral administration of 80 or 500 mg/head daily, divided into two equal doses given at 12‐h intervals for 8 days. These are the approved, and commonly used but unapproved, feed additive doses, respectively, in the United States for the prevention of ovine infectious abortion. Blood samples were collected just prior to dosing at 0, 12, 24, 72, 96, and 192 h, as well as 4, 8, 12, 24, and 36 h after the last dose, and noncompartmental pharmacokinetic analysis was performed to estimate elimination half‐life and area under the plasma concentration–time curve (AUC). Mean observed maximum CTC concentrations (C_max) were 20.0 ng/mL (80 mg dose) and 101 ng/mL (500 mg dose). Mean apparent elimination half‐life was 18 h (80 mg dose) and 20 h (500 mg dose). Although published data do not exist to estimate plasma CTC concentrations necessary for the prevention of ovine infectious abortion, concentrations reached in our study suggest that either the FDA‐approved and FDA‐unapproved dosages are not high enough or that the pharmacodynamic parameter relating preventive dose to pathogen minimum inhibitory concentrations is yet to be determined.     

Prevalence and Pathogenicity of Cryptosporidium suis in Pre‐ and Post‐weaned Pigs

A total of 4338 faecal samples, 135 of sows, 3368 of pre‐weaned and 835 of post‐weaned piglets from eight farms in South Bohemia, Czech Republic were collected and examined for Cryptosporidium infection. No sow, but 5.7% pre‐weaned and 24.1% post‐weaned piglets were positive for Cryptosporidium infection. No relationship was found between diarrhoea and Cryptosporidium infection in any of the different age groups (pre‐ and post‐weaned piglets). Four piglets, which were sporadically shedding cryptosporidia in faeces, were necropsied. Neither clinical signs of diarrhoea nor macroscopical changes were found. Histologically, a moderate infection of cryptosporidia was detected in the glandular epithelium along the large intestine, with predisposition to the ansa centralis of the colon. No inflammatory response in the lamina propria was observed. Cryptosporidia were also commonly found in the glandular epithelium of submucosal lymphoglandular complexes in the colon. Cryptosporidium isolates from all farms were identified as Cryptosporidium suis using molecular markers (SSU rRNA). All of the C. suis strains obtained were larger [6.2 (6.0–6.8) × 5.5 (5.3–5.7) μm] than any isolate described so far [4.6 (4.4–4.9) × 4.2 (4.0–4.3) μm] and did not appear to be infective for neonatal BALB/c mice.