Prevalence, molecular species, and associated factors for Cryptosporidium infection among dairy-farm workers and HIV-positive individuals in central Ethiopia: a cross-sectional study

Human Immunodeficiency Virus (HIV) positive patients and dairy farm workers are at increased risk of contracting Cryptosporidium infection due to compromised immunity and occupational exposure. This study aimed to determine the prevalence of Cryptosporidium infection and identify associated factors and molecular species of the parasite in HIV positive patients and dairy farm workers in central Ethiopia. A cross-sectional study was conducted using a two-stage random sampling technique to select 300 study participants. Approximately 5 g of stool was collected aseptically from each participant, transported to the laboratory, and examined using the modified Ziehl–Neelsen staining, Nested Polymerase Chain Reaction, Restriction Fragment Length Polymorphism, and sequence analysis. A pretested questionnaire was employed to collect data on infection-associated factors. Data were analyzed with the SPSS software using the univariable and multivariable logistic regression, with a 95% confidence interval and a precision level of p < 0.05. The overall prevalence of Cryptosporidium was 9% (95% CI: 5.7–12.3). Among dairy farm workers prevalence was 10.8% (95% CI: 5.7–16.0), while HIV positive individuals had 7.8% (95% CI: 3.6–12.0). Cryptosporidium parvum (C. parvum) and Cryptosporidium hominis (C. hominis) were identified at proportions of 81.5% and 18.5%, respectively. Phylogenetic analysis confirmed that C. parvum isolates belonged to the bovine genotype family. Infection was significantly associated with low education level, presence of animals at home, frequent contact with animal excrement, and drinking untreated well or stream water (P < 0.05). HIV positive patients on antiretroviral therapy (ART) with Cluster of Differentiation 4 (CD4+) counts of 200–500 cells per microliter (cells/µL) were significantly less likely to be infected than those who were pre- ART or had CD4 + counts below 200 cells/µL. The predominance of bovine genotype C. parvum, its association with untreated well or stream water, and the higher risk among HIV-positive individuals with low CD4 + counts underscore the public health importance of the infection and the need for integrated “One Health” control strategies.