Seroprevalence and risk factors for Canine Leishmaniasis in Jordan: Evidence for an indoor paradox and breeding kennel amplification.

BACKGROUND

Canine leishmaniasis (CanL) is a zoonotic threat in the Mediterranean basin caused by Leishmania spp, but its epidemiology has not been characterized in Jordan. This study was conducted to determine the true seroprevalence and identify risk factors for exposure of dogs to Leishmania spp. across three major governorates of Jordan.

METHODS

A cross-sectional study involving 341 dogs (stray, pet, and breeding) from Amman, Irbid, and Zarqa was carried out. Serum samples were analyzed using a commercial indirect ELISA kit (Demeditec, Germany). True prevalence was estimated by Rogan-Gladen adjustment with sensitivity and specificity values of 95.6% and 98.0%, respectively. Risk factors were identified through univariate analysis with odds ratios (OR).

RESULTS

The overall apparent seroprevalence was 7.33% (25/341), which corresponds to a true prevalence of 5.70% (95% CI: 3.6%-8.1%). The seroprevalence varied significantly by region attaining an extraordinary level of 17.7% in Irbid (OR = 5.59 against Amman, p < 0.001). Breeding dogs have the highest infection rate so far recorded at 15% (OR = 2.92 compared to all other dog types combined (pet, stray, guard); p = 0.015). In another surprising finding, indoor-housed dogs demonstrated significantly different seroprevalence than outdoor-housed dogs (11.6% vs. 5.0%; OR = 2.49; p = 0.044). More than one-third of the seropositive were apparently healthy indicating that they constitute a silent reservoir.

CONCLUSION

In Jordan, leishmaniasis is endemic in domestic dog population. Mandatory serological screening of breeding kennels combined with indoor vector-control measures should be implemented urgently as part of a One Health strategy.