The Evolution of Cystic Echinococcosis in Humans and Ruminants in Portugal—A One Health Approach

SIMPLE SUMMARY: Cystic echinococcosis, also known as hydatid disease, is a significant parasitic infection that affects animals and humans. In Portugal, there is limited information available about this disease despite its importance to public health. To better understand its impact, we collected data from ruminant slaughterhouses, human hospitalizations, and human-confirmed infection cases. Between 2008 and 2022, 298 cases of cystic echinococcosis were identified in ruminants slaughtered for human consumption from national farms in Portugal. Of these, 192 cases were in sheep, 95 in cattle, and 11 in goats. Among humans, the disease resulted in 582 hospitalizations, with an average stay of 11 days, and caused 13 deaths between 2008 and 2018. We found that each infected animal increased the likelihood of human hospitalization by 7%. Additionally, for every 100,000 person-years observed during the same period, there were approximately 0.528 hospitalizations. Living in the Alentejo region was associated with a 5.3-fold increase in hospitalization rates and an 8-fold higher risk of death from cystic echinococcosis. This collaborative One Health study provides valuable insights into the situation in Portugal and highlights the need for effective health control programs to prevent the spread of this neglected zoonosis. ABSTRACT: Cystic echinococcosis, also known as hydatid disease, is a significant parasitic zoonosis with public health implications, albeit often neglected. In Portugal, data on this zoonosis are scarce despite being a mandatory notifiable disease in both humans and animals. To assess the impact of cystic echinococcosis on both livestock and humans, we compiled data from slaughterhouse records of ruminants, human hospitalizations, and confirmed cases of human echinococcosis. Overall, a total of 298 cases of cystic echinococcosis were identified in ruminants slaughtered from national farms for human consumption in Portugal between 2008 and 2022, comprising 192 cases in ovines, 95 in bovines, and 11 in caprines. Echinococcosis led to 582 hospitalizations in Portuguese public hospitals, with an average hospital stay of 11 days (±15.66), and resulted in 13 deaths (2.23%) from 2008 to 2018. Each infected animal was associated with a 7% increase in the incidence rate of human hospitalization (p = 0.002, IRR = 1.070, 95% CI: 1.025–1.117). Additionally, for every 100,000 person-years observed between 2008 and 2018, the total number of hospitalizations was 0.528. Residence in the Alentejo region was associated with a 5.3-fold increase in the incidence rate of human hospitalizations and an 8-fold higher risk of death from echinococcosis.