The role of beetles in expanding of spread of parasitic infection with Hymenolepis nana

Abstract

Hymenolepis nana, commonly known as the dwarf tapeworm, is a significant zoonotic parasite with a cosmopolitan distribution. This study aimed to investigate the prevalence of H. nana infection in human populations and the role of stored-product beetles, specifically Tribolium confusum, as intermediate hosts within food substrates like flour and rice. A total of 75 human stool samples were collected and examined using the Petri dish method and Ziehl-Neelsen staining. Simultaneously, 200 food samples (100 flour and 100 rice) were analyzed for beetle infestation. Statistical analysis was performed using the Chi-Square test at a probability level of (p≤0.05).  The overall infection rate of H. nana was 24% (18/75 cases). While females showed a slightly higher infection rate (25.5%) compared to males (21.8%), the difference was not statistically significant. However, age was a critical factor; children under 10 years exhibited the highest prevalence (40%), which decreased significantly with age, reaching 17.6% in individuals over 40. Infection was strongly associated with gastrointestinal distress (p≤0.05), with abdominal pain (33.3%) and diarrhea (30%) being the most common symptoms. Notably, 8% of positive cases were asymptomatic. A highly significant difference was found in beetle infestation between food types. Flour recorded a dominant infestation rate of 70% and a prevalence of 93.88% (2,071 beetles), whereas rice showed only a 5% infestation rate and 6.12% prevalence (135 beetles).