Abstract
Background Leishmaniosis and other canine vector-borne diseases (CVBDs) pose a major risk for veterinary and public health globally, especially where humans and dogs live in close proximity. Although mosquito and tick vectors are abundant in Hong Kong, surveillance for CVBD has been limited.
Methods A serological and molecular survey of 158 healthy owned (n = 64) and free-roaming unowned (n = 94) dogs with outdoor access in Hong Kong was performed to determine CVBD prevalence. Point-of-care (POC) immunoassays were used to detect (i) antibodies to Leishmania spp., Ehrlichia spp., and Anaplasma spp., and (ii) Dirofilaria immitis and Angiostrongylus vasorum antigens, in canine sera. Conventional polymerase chain reaction (PCR) was also carried out to detect the molecular prevalence of all five pathogens as well as Hepatazoon canis, Babesia gibsoni, and Trypanosoma evansi. In addition, for Leishmania spp. detection, an immunofluorescence antibody test (IFAT) was performed on all serum samples, followed by real-time PCR of seropositive samples to detect Leishmania spp. DNA. The agreement between tests was assessed by Cohen’s kappa test, and logistic regression analysis was applied to identify risk factors.
Results Overall, 45.6% of dogs tested positive on molecular and/or serological tests for at least one pathogen, with the highest prevalence recorded for Dirofilaria spp. (20.9%), followed by B. gibsoni (15.2%), Leishmania spp. (11.4%), Anaplasma spp. (7.6%), H. canis (4.4%), Ehrlichia spp. (3.8%), and A. vasorum (0.6%). No T. evansi DNA was detected. Co-infections or co-pathogen exposure occurred in 16.5% of samples. Of the 33 Dirofilaria spp.-positive dogs, two were identified by sequencing as Dirofilaria asiatica, and the remaining 31 were D. immitis. No significant risk factors for infection or exposure were identified.
Conclusions This is the first epidemiological survey of Leishmania spp. infection in dogs from Hong Kong, highlighting the need for surveillance of competent vectors and further investigation of disease status in dog populations to confirm whether this pathogen is endemic. Given the high prevalence of CVBD, especially of D. immitis, preventive and control measures are advocated in order to mitigate risks to canine health and zoonotic infection.
© The Author(s) 2025.
Methods A serological and molecular survey of 158 healthy owned (n = 64) and free-roaming unowned (n = 94) dogs with outdoor access in Hong Kong was performed to determine CVBD prevalence. Point-of-care (POC) immunoassays were used to detect (i) antibodies to Leishmania spp., Ehrlichia spp., and Anaplasma spp., and (ii) Dirofilaria immitis and Angiostrongylus vasorum antigens, in canine sera. Conventional polymerase chain reaction (PCR) was also carried out to detect the molecular prevalence of all five pathogens as well as Hepatazoon canis, Babesia gibsoni, and Trypanosoma evansi. In addition, for Leishmania spp. detection, an immunofluorescence antibody test (IFAT) was performed on all serum samples, followed by real-time PCR of seropositive samples to detect Leishmania spp. DNA. The agreement between tests was assessed by Cohen’s kappa test, and logistic regression analysis was applied to identify risk factors.
Results Overall, 45.6% of dogs tested positive on molecular and/or serological tests for at least one pathogen, with the highest prevalence recorded for Dirofilaria spp. (20.9%), followed by B. gibsoni (15.2%), Leishmania spp. (11.4%), Anaplasma spp. (7.6%), H. canis (4.4%), Ehrlichia spp. (3.8%), and A. vasorum (0.6%). No T. evansi DNA was detected. Co-infections or co-pathogen exposure occurred in 16.5% of samples. Of the 33 Dirofilaria spp.-positive dogs, two were identified by sequencing as Dirofilaria asiatica, and the remaining 31 were D. immitis. No significant risk factors for infection or exposure were identified.
Conclusions This is the first epidemiological survey of Leishmania spp. infection in dogs from Hong Kong, highlighting the need for surveillance of competent vectors and further investigation of disease status in dog populations to confirm whether this pathogen is endemic. Given the high prevalence of CVBD, especially of D. immitis, preventive and control measures are advocated in order to mitigate risks to canine health and zoonotic infection.
© The Author(s) 2025.
| Original language | English |
|---|---|
| Article number | 289 |
| Number of pages | 10 |
| Journal | Parasites & Vectors |
| Volume | 18 |
| Online published | 20 Jul 2025 |
| DOIs | |
| Publication status | Published - 2025 |
Bibliographical note
Information for this record is provided by the author(s) concerned.Funding
This study was partially funded by a grant from City University of Hong Kong SGP-9380113 awarded to VB. IDEXX Laboratories and Boehringer Ingelheim Animal Health partially supported the research activities of TM. DO was partially supported by EU funding within the Next Generation EU-MUR PNRR Extended Partnership initiative on Emerging Infectious Diseases (Project no. PE00000007, INF-ACT). Frederic Beugnet is an employee of Boehringer Ingelheim Animal Health.
Research Keywords
- Anaplasma spp.
- Babesia gibsoni
- Canine vector-borne diseases
- Dirofilaria spp.
- Dirofilaria asiatica
- Ehrlichia canis
- Hepatozoon canis
- Hong Kong
- Leishmania spp.
- Trypanosoma evansi
Publisher's Copyright Statement
- This full text is made available under CC-BY 4.0. https://creativecommons.org/licenses/by/4.0/
