Prevalence of, and Factors Associated with Intestinal Parasites in Multinational Expatriate Workers in Al Ain City, United Arab Emirates: An Occupational Cross-Sectional Study

Genetic diversity of Cryptosporidium species from diarrhoeic ungulates in the United Arab Emirates

Cryptosporidiosis has previously been reported in animals, humans, and water sources in the United Arab Emirates (UAE). However, most reports were only to the genus level, or generically identified as cryptosporidiosis. We aimed to investigate the genetic diversity of Cryptosporidium species occurring in diarrhetic ungulates which were brought to the Central Veterinary Research Laboratory (CVRL) in Dubai. Using a combination of microscopic and molecular methods, we identified five species of Cryptosporidium occurring among ungulates in the UAE, namely C. parvum, C. hominis, C. xiaoi, C. meleagridis, and C. equi. Cryptosporidium parvum was the most prevalent species in our samples. Furthermore, we identified subtypes of C. parvum and C. hominis, which are involved in both human and animal cryptosporidiosis. This is also the first reported occurrence of Cryptosporidium spp. in the Arabian Tahr, to our knowledge. Since the animals examined were all in contact with humans, the possibility of zoonotic spread is possible. Our study correlates with previous reports in the region, building upon the identification of Cryptosporidium sp. However, there is a need to further investigate the endemic populations of Cryptosporidium, including more hosts, sampling asymptomatic animals, and location data.

Prevalence of intestinal parasites and comparison of detection techniques for soil-transmitted helminths among newly arrived expatriate labors in Jeddah, Saudi Arabia

Background

Diversity in clinical signs and symptoms are associated with soil transmitted diseases (STD), which are spread to humans by intestinal worms and transmitted in a variety of ways. There is a need for the present study, which aimed to investigate the prevalence of intestinal parasites and to compare between the common detection techniques for soil-transmitted helminths (STHs) among newly arrived expatriate labors in Jeddah, Saudi Arabia.

Methods

A total of 188 stool samples were analyzed by macroscopic examination, and microscopic examination using direct iodine smear and the formal ether sedimentation technique. Trichrome and modified Kinyoun's stains were used to confirm the morphology of any detected protozoa stages and oocyst of Cryptosporidium, respectively. A chromatographic immunoassay kit was used for Entamoeba histolytica, Giardia lamblia and Cryptosporidium. In addition, real-time PCR was employed only to identify various STHs.

Results

Out of 188, several types of parasites were detected in 35 samples (18.62%), of which some with multiple infections. Nine samples (4.79%) were positive for Entamoeba coli, seven samples (3.72%) for Trichuris trichiura, six samples (3.19%) for Necator americanus, four samples (2.13%) for Strongyloides stercoralis, four samples (2.13%) for Ascaris lumbricoides, four samples (2.13%) for E. histolytica, three samples (1.60%) for Blastocystis hominis and two samples (1.06%) for Ancylostoma duodenale. In comparison between laboratory techniques for STHs, real-time PCR was able to detect the DNA of 19 samples (10.1%) followed by Ritchie sedimentation technique (18, 9.6%), and direct smear (7, 3.7%) (p > 0.05).

Conclusion

The high rate of newly arrived foreign workers infected with intestinal parasites could lead to a risk to society. Continuous and regular surveys are needed to deal with the occurrence of intestinal parasitic infections including STHs. To improve the identification of these infections, we recommend a supporting infrastructure for the application of concentration methods and molecular assays.

Fate of Cryptosporidium and Giardia through conventional and compact drinking water treatment plants

Over the past three decades, a notable rise in the occurrence of enteric protozoan pathogens, especially Giardia and Cryptosporidium spp., in drinking water sources has been observed. This rise could be attributed not only to an actual increase in water contamination but also to improvements in detection methods. These waterborne pathogens have played a pivotal role in disease outbreaks and the overall escalation of disease rates in both developed and developing nations worldwide. Consequently, the control of waterborne diseases has become a vital component of public health policies and a primary objective of drinking water treatment plants (DWTPs). Limited studies applied real-time PCR (qPCR) and/or immunofluorescence assay (IFA) for monitoring Giardia and Cryptosporidium spp., particularly in developing countries like Egypt. Water samples from two conventional drinking water treatment plants and two compact units (CUs) were analyzed using both IFA and qPCR methods to detect Giardia and Cryptosporidium. Using qPCR and IFA, the conventional DWTPs showed complete removal of Giardia and Cryptosporidium, whereas Mansheyat Alqanater and Niklah CUs achieved only partial removal. Specifically, Cryptosporidium gene copies removal rates were 33.33% and 60% for Mansheyat Alqanater and Niklah CUs, respectively. Niklah CU also removed 50% of Giardia gene copies, but no Giardia gene copies were removed by Mansheyat Alqanater CU. Using IFA, both Mansheyat Alqanater and Niklah CUs showed a similar removal rate of 50% for Giardia cysts. Additionally, Niklah CU achieved a 50% removal of Cryptosporidium oocysts, whereas Mansheyat Alqanater CU did not show any removal of Cryptosporidium oocysts. Conventional DWTPs were more effective than CUs in removing enteric protozoa. The contamination of drinking water by enteric pathogenic protozoa remains a significant issue globally, leading to increased disease rates. Infectious disease surveillance in drinking water is an important epidemiological tool to monitor the health of a population.

Prevalence and associated risk factors of intestinal parasitic infections among children in pastoralist and agro-pastoralist communities in the Adadle woreda of the Somali Regional State of Ethiopia

BACKGROUND

Intestinal parasitic infections (IPIs) can cause illness, morbidity, and occasional mortality in children. Agro-pastoralist and pastoralist children in the Somali Regional State of Ethiopia (ESRS) are especially at risk for IPIs, as access to safe water, sanitation, and health services is lacking. Minimal data on the prevalence of IPIs and associated risk factors exists in this region.

METHODOLOGY

We assessed the prevalence of IPIs and associated risk factors during the wet season from May-June 2021 in 366 children aged 2 to 5 years in four agro-pastoralist and four pastoralist kebeles (wards) in Adadle woreda (district) of the Shebelle zone, ESRS. Household information, anthropometric measurements, and stool samples were obtained from included children. Parasites were identified microscopically using Kato-Katz and direct smear methods. Risk factors were assessed using general estimating equation models accounting for clustering.

PRINCIPAL FINDINGS

Overall prevalence of IPIs was 35%: 30.6% for single infections and 4.4% for poly-parasitic infections. Intestinal protozoan prevalence was 24.9%: 21.9% Giardia intestinalis, and 3.0% Entamoeba spp.. Intestinal helminth prevalence was 14.5%: 12.8% Ascaris lumbricoides, 1.4% hookworm (Ancylostoma duodenale /Necator americanus.), and 0.3% Hymenolepis nana. G. intestinalis infection was associated with drinking water sourced from the river (aOR 15.6, 95%CI 6.84, 35.4) and from collected rainwater (aOR 9.48, 95%CI 3.39, 26.5), with toilet sharing (aOR 2.93, 95%CI 1.36, 6.31) and with household ownership of cattle (1-5 cattle: aOR 1.65, 95%CI 1.13, 2.41; 6+ cattle: aOR 2.07, 95%CI 1.33, 3.21) and chickens (aOR 3.80, 95%CI 1.77, 8.17). A. lumbricoides infection was associated with children 36 to 47 months old (aOR 1.92, 95%CI 1.03, 3.58).

CONCLUSIONS/SIGNIFICANCE

Improving access to safe water, sanitation, and hygiene services in Adadle and employing a One Health approach would likely improve the health of children living in (agro-) pastoralist communities in Adadle and the ESRS; however, further studies are required.

The associated risk of Blastocystis infection in cancer: A case control study

Background

Blastocystis is an anaerobic intestinal protozoan. Nine Blastocystis subtypes (STs) were detected in humans. A subtype-dependent association between Blastocystis and different cancer types has been debated in many studies. Thus, this study aims to assess the possible association between Blastocystis infection and cancer, especially colorectal cancer (CRC). We also screened the presence of gut fungi and their association with Blastocystis.

Methods

We used a case-control design; cancer patients and cancer-free (CF) participants. The cancer group was further sub-group into CRC group and cancers outside the gastrointestinal tract (COGT) group. Macroscopic and microscopic examinations were performed to identify intestinal parasites in participants' stool samples. Molecular and phylogenetic analyses were conducted to identify and subtype Blastocystis. Furthermore, gut fungi were investigated molecularly.

Results

104 stool samples were collected and matched between CF (n=52) and cancer patients (n=52); CRC (n=15) and COGT (n=37). As anticipated, Blastocystis prevalence was significantly higher among CRC patients (60%, P=0.002) and insignificant in COGT patients (32.4%, P=0.161) compared to CF group (17.3%). The most common subtypes were ST2 among cancer group and ST3 in the CF group.

Conclusion

Cancer patients have a higher risk of Blastocystis infection compared to CF individuals (OR=2.98, P=0.022). Increased risk of Blastocystis infection was associated with CRC patients (OR=5.66, P=0.009). Nevertheless, further studies are required to understand the underlying mechanisms of Blastocystis and cancer association.

Improving Diagnosis of Intestinal Parasites Towards a Migrant-Friendly Health System

Purpose of Review

This study describes the results obtained by the World Health Organization (WHO) collaborating centre (CC) for the diagnosis of intestinal helminths and protozoa (WHO CC ITA-116) during the first 2 years of its activity on (i) the prevalence of intestinal parasites in migrants in southern Italy and (ii) the development and application of new diagnostic tools for intestinal helminths (e.g. FLOTAC, Mini-FLOTAC Kit 200 tests, Kubic FLOTAC microscope (KFM)).

Recent Findings

Almost 23.3% of migrants examined were positive for at least one intestinal parasite. Moreover, a significant correlation was found between the duration of stay in Italy and positivity for intestinal parasites. The results of the comparison between diagnostic techniques showed a perfect agreement between FLOTAC and Mini-FLOTAC Kit 200 tests whereas no statistically significant differences were found between the count of helminth eggs obtained by Mini-FLOTAC with optical microscope and KFM.

Summary

The results obtained by WHO CC ITA-116 during the first 2 years of its activity provide important information on innovations in parasitological diagnosis and add data to the parasitological scenario of migrants arriving in southern Italy, highlighting the importance of regular parasitological monitoring.

A review of the molecular epidemiology of Cryptosporidium spp. and Giardia duodenalis in the Middle East and North Africa (MENA) region

Cryptosporidium spp. and Giardia duodenalis are important protozoan parasites which are associated with diarrheal diseases in humans and animals worldwide. Relatively little is known about the molecular epidemiology of Cryptosporidium spp. and Giardia duodenalis in the Middle East Countries and North Africa (MENA region). Therefore, this review aimed to inspect published genotyping and subtyping studies on Cryptosporidium spp. and Giardia duodenalis in the MENA region. These studies indicate that both anthroponotic and zoonotic transmission of Cryptosporidium occurs with the predominance of zoonotic transmission in most countries. Seven Cryptosporidium species were identified in humans (C. parvum, C. hominis, Cryptosporidium meleagridis, C. felis, Cryptosporidium muris, C. canis and C. bovis), with C. parvum by far being the most prevalent species (reported in 95.4% of the retrieved studies). Among C. parvum gp60 subtype families, IIa and IId predominated, suggesting potential zoonotic transmission. However, in four MENA countries (Lebanon, Israel, Egypt and Tunisia), C. hominis was the predominant species with five subtype families reported including Ia, Ib, Id, If and Ie, all of which are usually anthroponotically transmitted between humans. In animals, the majority of studies were conducted mainly on livestock and poultry, 15 species were identified (C. parvum, C. hominis, C. muris, Cryptosporidium cuniculus, C. andersoni, C. bovis, C. meleagridis, C. baileyi, C. erinacei, C. ryanae, C. felis, C. suis, Cryptosporidium galli, C. xiaoi and C. ubiquitum) with C. parvum (IIa and IId subtypes) the dominant species in livestock and C. meleagridis and C. baileyi the dominant species in poultry. With G. duodenalis, five assemblages (A, B, C, E and F) were identified in humans and six (A, B, C, E, D and F) in animals in MENA countries with assemblages A and B commonly reported in humans, and assemblages A and E dominant in livestock. This review also identified a major knowledge gap in the lack of Cryptosporidium spp. and Giardia duodenalis typing studies in water and food sources in the MENA region. Of the few studies conducted on water sources (including drinking and tap water), ten Cryptosporidium species and four genotypes were identified, highlighting the potential role of water as the major route of Cryptosporidium spp. transmission in the region. In addition, three G. duodenalis assemblages (A, B and E) were detected in different water sources with AI, AII and BIV being the main sub-assemblages reported. More research is required in order to better understand the molecular diversity and transmission dynamics of Cryptsporidum spp. and Giardia duodenalis in humans, animals, water and food sources in MENA region.

Intestinal parasitic infection among foreign housemaids in northwestern Saudi Arabia: A cross-sectional study

Owing to Saudi Arabia's high-income economy many Saudi families hire foreign housemaids. However, since the housemaids are potential carriers of intestinal parasites, hiring them increases the risk of transmission to the Saudi community. In this context, this study aimed to evaluate the prevalence of intestinal parasitic infections in foreign housemaids in northwestern Saudi Arabia. Using direct wet mount and concentration by flotation, the stool samples of 169 housemaids were examined, and eleven parasite species, six helminths and five protozoans, were detected. The overall prevalence of intestinal parasitic infection was 20.11% (34/169). Twelve cases were infected with one intestinal helminth, 12 were infected with one intestinal protozoan, and 10 had polyparasitism. The most common intestinal parasites were Cryptosporidium spp. (n = 10), hookworms (n = 7), and T. Trichiura (n = 7). The findings highlight that intestinal parasites present an important public health concern for foreign housemaids in Saudi Arabia. More vigilance is thus required, and periodic follow-up should be exercised throughout foreign housemaids' stay in the country.

Cryptosporidium and Cryptosporidiosis: The Perspective from the Gulf Countries

The present review discusses the burden of cryptosporidiosis in the Gulf Cooperation Council (GCC), which is underreported and underestimated. It emphasizes that the Cryptosporidium parasite is infecting inhabitants and expatriates in the Gulf countries. Children under 5 years are a vulnerable group that is particularly affected by this parasitic disease and can act as carriers, who contribute to the epidemiology of the disease most probably via recreational swimming pools. Various risk factors for cryptosporidiosis in the GCC countries are present, including expatriates, predisposing populations to the infection. Water contamination, imported food, animal contact, and air transmission are also discussed in detail, to address their significant role as a source of infection and, thus, their impact on disease epidemiology in the Gulf countries' populations.