Cystic Echinococcosis: An Impact Assessment of Prevention Programs in Endemic Developing Countries in Africa, Central Asia, and South America

Table 4

Appraisal summary of Article Meeting Inclusion Criteria [6].

Population:	Rio Negro province (Northern Patagonia), Argentina: (i) Province area: 120,013 km^2; (ii) Population density: 0.88 inhabitants/km^2; (iii) Dogs living on livestock (sheep and goat) farms; (iv) School Children (6-14 years old) associated with 13 program areas (hospitals) and 80 Primary Health Care Centers (PHCCs)
Sample size:	(i) 1790 canine fecel samples; (ii) 34,515 school children (6-14 years old)
Program outputs:	Definitive hosts (dogs); (i) Praziquantel (PZQ) de-wormer (5 mg/kg four times a year). Administered by 65 rural health assistants (tablets smeared in liver pate) or dog owners; Intermediate hosts; (i) Livestock: vaccination (EG95) from 2006; (ii) Children: ultrasound (US) screening by trained general physicians. All cases surveyed to identify potential exposure sites (e.g., relationship to livestock). Case follow-ups within hospitals; (iii) Community surveys conducted by veterinarians, doctors, and surgical services; (iv) Sanitary education: 65 rural health assistants
Study design:	Randomized prospective cross-sectional study
Program outcomes and/or impact:	CE prevalence in three sampling periods (2003–2005, 2009–2010, 2017–2018): Dogs: (i) Positive CoproELISA samples confirmed by Western blot (WB) (2003–2005; 2009–2010) and PCR (2017-2018); (ii) Samples collected using sterile methods and stored at −40 °C until processing; (iii) Veterinarians () provided technical and scientific support; Children: (i) US screening across 13 public hospitals and 80 primary health centers; (ii) Temporal-spatial heat mapping (QGIS 3.4.6) of human cases in areas with highest proportion of CE positive dogs
Main findings:	Prevalence in dogs (definitive host): (i) Canine positive fecel samples by CoproELISA: 32.0% (2003-2005), 32.9% (2009-2010), and 15.6% (2017-2018). Between 2003-2018, 16.4% decrease in prevalence; (ii) Subsequent confirmation tests (WB and PCR) over three testing periods: 14.7% (95% CI, 10.7–19.5), 12.1% (95% CI, 8.1–16.2), and 7.4% (95% CI, 4–7–11.9). A 7.3% prevalence decrease detected from positive canine fecel samples; (iii) Prevalence differences between the first (2003-2005) and third (2017-2018) period statistically significant (, ), based upon Chi-squared linear (EPIDAT 3.1) trend analysis. Not significant between periods one-two or two-three; Prevalence in children (6-14years) (intermediate host): (i) In periods 2003–2008, 2009–2016, and 2017–2018: 0.4% (95% CI, 0.3–0.6), 0.2% (95% CI, 0.1–0.3), and 0.1% (95% CI, 0.05–0.3), respectively, calculated. Between 2003-2018: 0.3% decrease, with 95 asymptomatic cases diagnosed with hepatic CE; (ii) Statistically significant differences: first (2003-2008) and second period (2009-2016) (, ); not second-third (, ); (iii) Highest livestock farm prevalence: Andean and Pre-Andean regions (program areas of Ñorquinco, Comallo, and Pilcaniyeu); the central plateau of the province (Ingeniero Jacobacci, Los Menucos, and Maquincha); and in the east (Valcheta and Ramos Mexia); Barriers (limited access to diagnostic, treatment, and prevention services): (i) Harsh or remote climatic terrain limited access or delivery of resources; (ii) Infrastructure constraints: poorly structured roads limited frequent and safe travel; (iii) Poor sanitation: little knowledge about sanitary practices. Minimal sanitation infrastructure to dispose of infected offal; (iv) Distance between rural hospitals and primary health centers (normally >80/100 km); (v) Missed PZQ administration, causing reinfection in dogs; (vi) Urbanization: increasing rural to urban transmission from dogs to children, due to increasing domestic slaughter of small ruminants in cities
Limitations:	(i) No clearly defined research question; (ii) Information bias: temperature fecel samples collected not reported. Hotter summers and freezing winters can decrease CE egg lifespan, compared to ideal temperatures in Autumn or Spring; (iii) Result reliability: CoproELISA tests confirmed by two different methods: WB in first two study periods and PCR in the last; (iv) Limited sensitivity of US in detecting pulmonary cysts; (v) Sample size calculation: prevalence treated as a single independent proportion for each sample population (dogs and children). Comparing two independent proportions may be more suitable, as the two populations were treated as interdependent; (vi) Few details about community survey method (e.g., verbal, written, and electronic) or question type (open, closed, and MCQ); (vii) CoproELISA results not instantaneous. Thus, control measures may be delayed; Confounding variables; (i) Did not distinguish between owned and stray dogs; (ii) Non-standardized PZQ administration: owner and rural health workers; (iii) Researchers not blinded to de-worming administration method (e.g., if farmers or rural health workers de-wormed dogs); (iv) List “sanitary education” as a program output, but do not measure behavioral outcomes