Global variation in force-of-infection trends for human Taenia solium taeniasis/cysticercosis

Prevalence of Cysticercosis in Pigs and Risk Assessment Among Occupationally Exposed Workers in Benue State, Nigeria

AIM

Cysticercosis is a key zoonotic disease burden, posing significant public health challenges. Neurocysticercosis, a sequela associated with the larval stage of Taenia solium, is a recognised cause of late-onset epilepsy in humans, thereby highlighting the need for robust epidemiological data. This study investigated the prevalence of cysticercosis in slaughtered pigs within Makurdi, Benue State, Nigeria, to contribute to understanding the disease's local epidemiology and associated risk factors.

METHODS

From January to August 2019, we examined pig carcasses at four abattoirs: Utyondo market, Wurukum abattoir, Modern market, and Railway abattoirs. Structured questionnaires were administered to butchers, pig farmers, and civil servants to gather information on disease knowledge. A total of 2,176 pig carcasses were examined.

RESULTS

Among the examined carcasses, 24 (1.1%) were infected. Of these, 18 (0.83%) were boars, and 6 (0.28%) were sows. The highest prevalence was observed in Utyondo market (2.75%), followed by Wurukum (0.77%) and Railway markets (0.65%). The diaphragm (odds ratio (OR) = 0.09; 95% confidence interval (CI): 0.01-0.70) and the tongue (OR = 0.18; 95% CI: 0.04-0.81) were less likely to be infected compared to the shoulder. Knowledge of cysticercosis was relatively high across all participants (71.72%, 95% CI: 61.77-80.31).

CONCLUSION

Our findings indicate the endemicity of porcine cysticercosis in Makurdi abattoirs. While knowledge of the disease seems relatively widespread among exposed populations, gaps exist in understanding transmission routes. A collaborative One Health approach involving studies on occupationally exposed individuals is recommended for a comprehensive understanding of the disease burden and to develop targeted control strategies.

Isolated intramuscular cysticercosis of the forearm masquerading as malignancy

A woman in her mid-20s presented to an Indian tertiary care hospital with pain in her left forearm. Extensive initial investigations led to a suspected diagnosis of a peripheral nerve sheath tumour; however, the pathological investigation of the excised tumour mass revealed it to be a case of isolated intramuscular cysticercosis in the forearm. Treatment for cysticercosis was commenced and the patient made a full recovery. Isolated intramuscular cysticercosis without the involvement of other organs is a rare presentation and has only been reported in a handful of case reports. We suggest that isolated intramuscular cysticercosis be considered a differential diagnosis in patients with isolated pain in their muscles and with no other symptoms, in patients with a presentation of solitary swelling and in patients at risk of parasitic infection. In addition, we emphasise the importance of histopathological examination due to the varied presentation of cysts.

Triplex ELISA for Assessing Durability of Taenia solium Seropositivity after Neurocysticercosis Cure

Neurocysticercosis prevalence estimates often are based on serosurveys. However, assessments of Taenia solium seropositivity durability in patients with various neurocysticercosis types are lacking. We optimized a triplex serologic ELISA by using synthetic GP50, T24H, and Ts18var3 antigens for T. solium. We used that assay to test sequential serologic responses over several years after neurocysticercosis cure in 46 patients, 9 each with parenchymal or ventricular neurocysticercosis and 28 with subarachnoid disease. Triplex results were concordant with 98% of positive and 100% of negative enzyme-linked immunoelectrotransfer blots. Eight years after neurocysticercosis cure, 11.1% of patients with parenchymal, 47.3% with subarachnoid, and 41.7% with ventricular disease were still seropositive. Median time to seroreversion after cure in this cohort in a T. solium nonendemic area was 2 years for parenchymal disease, 4 years for ventricular disease, and 8 years for subarachnoid disease. Our findings can inform epidemiologic models that rely on serosurveys to estimate disease burden.

Taenia solium taeniasis and Cysticercosis Prevalence and Control Practice in China

Taenia solium taeniasis/cysticercosis is an important global food-borne zoonosis transmitted between humans and pigs. In China, the prevalence of Theridion solium taeniasis/cysticercosis has been marked decline in recent decades based on the data revealed by both national surveys and field prevalence investigations. Health education and promotion, meat inspection, and chemotherapy are unquestionably the main control measures for diseases. It is worth noting that a variety of socio-ecological variables have been identified in the process of controlling T. solium taeniasis/cysticercosis. It has become difficult for pigs to come into direct or indirect contact with or consume human excreta as pig farming practices have been shifted from traditional backyard farms to large-scale commercial pig raising systems that are still in progress. The human toilet revolution in rural areas of China has ensured hygienic separation of human excreta from contact, and thereby preventing human excreta from polluting the soil, feeds, and water. These two important fundamental preventive measures are crucial to establishing an environmental restriction between humans and pigs cannot be overlooked for interrupting or limiting T. solium transmission. In this chapter, we reviewed the epidemiology, traditional measures, and ecological determinants that significantly contributed to the dramatic decline of taeniasis/cysticercosis in China.