Burden and Epidemiology of Human Intestinal Giardia duodenalis Infection in Colombia: A Systematic Review

The Influence of the Protozoan Giardia lamblia on the Modulation of the Immune System and Alterations in Host Glucose and Lipid Metabolism

Giardia lamblia, the cause of giardiasis, significantly impacts patients with metabolic disorders related to insulin resistance (IR). Both giardiasis and metabolic disorders share elements such as chronic inflammation and intestinal dysbiosis, which substantially affect the metabolic and cytokine profiles of patients. This review discusses the mechanisms of virulence of G. lamblia, its influence on the immune system, and its association with metabolic disorders. The review aims to show how G. lamblia invasion acts on the immune system and the glucose and lipid metabolism. Key findings reveal that G. lamblia infection, by disrupting intestinal permeability, alters microbiota composition and immune responses, potentially impairing metabolic status. Future research should focus on elucidating the specific mechanisms by which G. lamblia influences the metabolism, exploring the long-term consequences of chronic infection, and developing targeted therapeutic strategies that include both parasitic and metabolic aspects. These insights underscore the need for a multidisciplinary approach to the treatment of giardiasis in patients with metabolic disorders.

Gastrointestinal parasites of owned cats in three districts of Central Ethiopia: Prevalence and risk factors

This present, cross-sectional study investigated gastrointestinal parasites in owned cats was carried out across Bishoftu, Dukem, and Addis Ababa city and towns in Central Ethiopia from February 2022 to April 2023. The primary objectives were to estimate the prevalence and assess the risk factors associated with these parasites. A total of 213 faecal samples were collected and processed using flotation and McMaster techniques. An overall prevalence of 34.7% (74/213) of gastrointestinal parasites was recorded in the examined cats. The cats harboured nematode (14.6%), cestode (12.7%), and protozoan (5.6%) parasites in single (32.9%) and mixed (1.9%) species. Specifically, Toxocara cati, Dipylidium caninum, Taenia spp., Giardia spp., and Physaloptera spp. were the more frequently identified parasites, with prevalences of 9.4%, 8.9%, 3.8%, 2.8%, and 2.8%, respectively. Statistically significant differences (P < 0.05) were observed in the prevalence of gastrointestinal parasites among cats of different sexes, ages, and feeding conditions. Thus, higher prevalence rates were observed in females (49.1%, OR = 2.3), young cats (70%, OR = 4.7), and those consuming uncooked food (40.5%, OR = 3.6). Faecal consistency also showed a statistically significant association (P < 0.05) with the presence of gastrointestinal parasites. However, no significant differences were noted in the prevalence among cats of different housing conditions, seasons, or agro-ecological zones. Cats sharing shelter with families had the highest prevalence of gastrointestinal parasites (52.2%). In conclusion, this study uncovered a notably high occurrence of gastrointestinal parasites in cats in the surveyed regions, emphasizing the imperative of adopting a One Health strategy to address the zoonotic parasites found in cats, which pose significant public health risks.

Food and Drinking Water as Sources of Pathogenic Protozoans: An Update

This narrative review was aimed at collecting updated knowledge on the risk factors, illnesses caused, and measures for the prevention of protozoan infections transmitted by food and drinking water. Reports screened dated from 2019 to the present and regarded global prevalence in food handlers, occurrence in food and drinking water, impact on human health, and recently reported outbreaks and cases of severe infections attributable to the dietary route. Cryptosporidium spp., Cyclospora cayetanensis, Entamoeba histolytica, and Cystoisospora belli were the protozoans most frequently involved in recently reported waterborne and foodborne outbreaks and cases. Blastocystis hominis was reported to be the most widespread intestinal protozoan in humans, and two case reports indicated its pathogenic potential. Dientamoeba fragilis, Endolimax nana, and Pentatrichomonas hominis are also frequent but still require further investigation on their ability to cause illness. A progressive improvement in surveillance of protozoan infections and infection sources took place in developed countries where the implementation of reporting systems and the application of molecular diagnostic methods led to an enhanced capacity to identify epidemiological links and improve the prevention of foodborne and waterborne protozoan infections.

Molecular Prevalence and Subtypes Distribution of Blastocystis spp. in Humans of Latin America: A Systematic Review

Blastocystis spp. are among the few enteric parasites with a prevalence that can reach up to approximately 80% in communities of developing countries. This systematic review updates and summarizes available literature on the molecular prevalence and subtype distribution of Blastocystis spp. in Latin American people. This work follows the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. The literature revised covers from 1 January 2015 to 6 October 2023 in seven different scientific databases, and the material was selected through inclusion and exclusion criteria. According to data found in the 36 selected articles, the prevalence of Blastocystis spp. in Latin America ranged between 5.8% (Bolivian rural communities) and 94.0% (Colombian general public). Generally, genomic DNA was extracted from approximately 200 mg fecal sediments using commercial kits, such as the QIAamp Stool Mini Kit (QIAGEN, Hilden, Germany) or the Norgen Stool DNA Isolation Kit (Norgen Biotek Corporation, Thorold, ON, Canada). Subtype-specific primers (such as the couple of primers BhRDr-RD5) developed from unique sequences of the SSU rRNA gene were applied to Blastocystis subtyping. Ten specific subtypes (STs) were found as well as various mixed infections, and the most circulating Blastocystis STs were in the order ST3, ST1, ST2, and ST4. The most recent data about Blastocystis spp. molecular epidemiology and the STs in communities of Latin America are limited to studies from specific countries. Novel scientific data from the other countries are required to obtain a complete picture and truly understand the distribution and prevalence of Blastocystis spp. and the STs.

Endoparasites in domestic cats (Felis catus) in the semi-arid region of Northeast Brazil

The aim of this study was to evaluate the prevalence of endoparasites in domestic cats (Felis catus) in the city of Sousa, state of Paraíba, Northeast Brazil. A total of 207 samples of fresh feces were randomly collected from domestic and semi-domiciled cats. The samples were analyzed by simple centrifugation and centrifuge-flotation in sucrose solution for the diagnosis of helminth eggs and enteric protozoan oocysts and cysts. Epidemiological information was obtained to determine risk factors related to infections. Among the samples collected, 81.6% (169/207; 95% CI: 77.4-83.8) were positive for at least one parasite genus. Ancylostoma spp. was the most prevalent, at 67.1% (139/207), followed by Taenia spp. at 28.5% (59/207), and Spirometra spp. and Platynosomum sp., both at 17.3% (36/207). The variables associated with helminth infection were a historic lack of deworming (Odds ratio = 12.25) and the presence of dry fur (Odds ratio = 2.15). No risk factors were observed for enteric protozoa infection. This study demonstrated a high prevalence of endoparasites in domestic cats in the city of Sousa, state of Paraíba, and associated risk factors, thus establishing an overview of the main helminths and protozoa that affect cats in this region.

Change in the incidence of intestinal diseases caused by parasitic protozoa in the Mexican population during the period (2015-2019) and its association with environmental and socioeconomic risk factors

Diarrheal diseases are one of the main health problems worldwide, especially in developing countries with poor health systems, high rates of poverty, and poor nutrition. The main causative agents of diarrheal disease are bacteria, viruses, and parasites; among the latter, the intestinal protozoa Giardia and Entamoeba stand out. In the present work, a observational analysis of the national surveillance data of amebiasis, giardiasis, and other protozoan intestinal infections was carried out. The data issued by the Directorate General of Epidemiology was analyzed to establish its relationship with geography, socioeconomic, and environmental conditions in Mexico during the 2015-2019 period. New cases of amebiasis decreased by 25.03% between 2015 and 2019, while giardiasis and other protozoan intestinal infections remained constant; in all cases, incidence was higher in females than in males, and children under 5 years of age were the most affected. The contribution of environmental conditions (seasonality, temperature, and humidity) and socioeconomic factors in the number of protozoan intestinal infection cases was assessed by a multivariable regression model using a backward selection procedure. Peaks in cases were observed in spring and summer, which are characterized by warm and humid climates. Additionally, states with high humidity and annual average temperature contribute to a notably higher incidence of these parasites, especially annual average temperature, as demonstrated through multivariable linear regression models. Moreover, the majority of these states have the largest population living in poverty with inadequate measures for the distribution, dispensing, and sanitation of water. These data are essential to incidence rate monitoring and focus efforts on eliminating risk factors and improving health programs in Mexico.