Molecular detection of tick-borne pathogens in canine population and Rhipicephalus sanguineus (sensu lato) ticks from southern Metro Manila and Laguna, Philippines

Abstract

BackgroundThe tropical climate of the Philippines and the high population of dogs, particularly in cities, favors the life-cycle of the brown dog tick, Rhipicephalus sanguineus (sensu lato), a vector of several canine tick-borne pathogens (TBPs) including zoonotic Rickettsia spp. Suspected cases of infections are commonly encountered in veterinary clinics, but the specific TBPs are rarely identified. Furthermore, infection with Rickettsia is not being clinically examined in dogs. In this study, the occurrence of TBPs in blood and ticks collected from household and impounded dogs in highly populated areas of the Philippines, Metro Manila, and the nearby province of Laguna, was examined.ResultsA total of 248 blood samples and 157 tick samples were subjected to PCR. First, samples were screened using primers for Anaplasma/Ehrlichia spp. and Babesia/Hepatozoon spp. Those that turned positive were further subjected to species-specific PCR. Rickettsia spp. were also detected through a nested PCR. Of the 248 blood samples, 56 (22.6%) were positive for Anaplasma/Ehrlichia spp., while 19 (7.6%) were positive for Babesia/Hepatozoon spp. Species-specific PCR revealed that 61 (23.4%) had a single TBP, with Ehrlichia canis being detected in 39 (15.7%) dogs, while 14 (5.6%) dogs were positive for different combinations of two to four TBPs. Rickettsia infection was detected in 6 (2.4%) dogs. In tick samples, 8 (3.2%) were positive for Ehrlichia/Anaplasma spp., while only 1 (0.63%) was positive for Babesia/Hepatozoon spp. As in the blood samples, E. canis was the most detected, being found in 5 (2%) samples. No tick samples tested positive for Rickettsia spp.ConclusionEhrlichia canis is the most common TBP affecting dogs in the Philippines. Co-infection with TBPs is quite common, hence testing for multiple TBPs is necessary. Through nested PCR, Rickettsia infection was detected in dogs, and to the authors’ knowledge, this study provides the first molecular evidence of Rickettsia infection in dogs in the Philippines.

Molecular Detection of Rickettsia spp. and Coxiella burnetii in Cattle, Water Buffalo, and Rhipicephalus (Boophilus) microplus Ticks in Luzon Island of the Philippines

“…Recently, our group detected Rickettsia in dogs from Laguna, one of the provinces in this study, through the same nested PCR employed in this study. It was found that the amplicons were highly identical to R. japonica after sequence analysis [33].…”

“…Camer et al [31] demonstrated the presence of antibodies against the SFG and TG Rickettsia and C. burnetii in humans by indirect immunofluorescent antibody test (IFAT), whereas Cardona [32] used complement fixation for serological testing of C. burnetii in domestic ruminants and humans. Recently, a study from our group utilizing nested PCR provided evidence for the presence of Rickettsia in dogs in the Philippines [33]. Here, we investigate the presence of Rickettsia and C. burnetii in cattle and water buffalo, as well as R.…”

Molecular detection of tick-borne haemopathogens in shelter dogs and Rhipicephalus sanguineus (sensu lato) ticks from Peninsular Malaysia

“…Tick-borne diseases are a common problem worldwide and has increase in their importance due to the capability of causing critical illness as well as possibility of death in infected human and animals [1][2][3]. Tick-borne haemopathogens (TBH) were closely related to the companion animals which act as resevoir of the various pathogen but also a potential victim that could harm this cats and dogs [4].…”

Molecular detection of pathogens in ticks and fleas collected from companion dogs and cats in East and Southeast Asia

“…sanguineus s.l. This protozoan is commonly found in dogs in Thailand, Taiwan, China, Cambodia, Malaysia, Philippines and Vietnam [10, [17][18][19][23][24][25] and in cats in Thailand and Philippines [10,23]. Of the tick-borne anaplasmatacea bacteria, Anaplasma platys was found in dogs from Cambodia [18] and cats from Thailand [26].…”