Domestic dogs, Canis lupus, have been one of the longest companions of humans and have introduced their own menagerie of parasites and pathogens into this relationship. Here, we investigate the parasitic load of 212 domestic dogs with fleas (Siphonaptera) chewing lice (Phthiraptera), and ticks (Acarina) along a gradient from rural areas with near-natural forest cover to suburban areas in Northern Borneo (Sabah, Malaysia). We used a spatially-explicit hierarchical Bayesian model that allowed us to impute missing data and to consider spatial structure in modelling dog infestation probability and parasite density. We collected a total of 1,968 fleas of two species, Ctenocephalides orientis and Ctenocephalides felis felis, from 195 dogs (prevalence, 92 %). Flea density was higher on dogs residing in houses made of bamboo or corrugated metal (increase of 40 % from the average) compared to timber or stone/compound houses. Host-dependent and landscape-level environmental variables and spatial structure only had a weak explanatory power. We found adults of the invasive chewing louse Heterodoxus spiniger on 42 dogs (20 %). The effect of housing conditions was opposite to those for fleas; lice were only found on dogs residing in stone or timber houses. We found ticks of the species Rhipicephalus sanguineus as well as Haemaphysalis bispinosa gp., Haemaphysalis cornigera, Haemaphysalis koenigsbergi, and Haemaphysalis semermis on 36 dogs (17 %). The most common tick species was R. sanguineus, recorded from 23 dogs. Tick infestations were highest on dogs using both plantation and forest areas (282 % increase in overall tick density of dogs using all habitat types). The infestation probability of dogs with lice and ticks decreased with elevation, most infestations occurred below 800 m above sea level. However, the density of lice and ticks revealed no spatial structure; infestation probability of dogs with these two groups revealed considerable autocorrelation. Our study shows that environmental conditions on the house level appeared to be more influential on flea and lice density whereas tick density was also influenced by habitat use. Infestation of dogs with Haemaphysalis ticks identified an important link between dogs and forest wildlife for potential pathogen transmission.
The occurrence of canine hepatozoonosis in Thailand is primarily caused by Hepatozoon canis. Recently, the relationship of hematology and biochemistry with this disease has been studied, but knowledge regarding the relationship between the quantity of H. canis intracellular gamonts and the hematological profile has not yet been reported. The objective of this study was to investigate the clinical, hematological and biochemical profile of H. canis-positive dogs and the relationship of the number of H. canis gamonts, animal signalment, and hematological and biochemical values. A total of 185 H. canis-positive blood samples were examined, including buffy coat smears and comprehensive data. The number of gamonts was randomly counted from buffy coat smears samples (75/185). The dogs infected with H. canis presented to the animal hospital mostly for health status checks, anorexia, or accidents. Observations from the physical examination on the first day of registration included systemic abnormalities such as digestive, integument, respiratory, urogenital, etc. Most of the dogs showed clinical signs of systemic abnormality in more than one system. Our study shows that plasma proteins are correlated with the number of H. canis gamonts, using Spearman's rho correlation coefficient with significant difference (p <0.05). This finding could be applied to improve the diagnosis and treatment of canine hepatozoonosis.
A total of 764 adult dogs were examined for microfilariae and adult worms of D immitis and 197 (25-8 per cent) were found to be infected. Direct blood examinations revealed only 47-2 per cent of the infected dogs whereas the blood serum examination detected 57-8 per cent of them. These results showed that the absence of circulating microfilariae could not be relied upon to be an accurate indication of the absence of patent heartworm infection. The average number of heartworms per dog was 5-5 with a range of one to 50.
A gastrointestinal parasite survey of 411 stray and refuge dogs sampled from four geographical and climactically distinct locations in India revealed these animals to represent a significant source of environmental contamination for parasites that pose a zoonotic risk to the public. Hookworms were the most commonly identified parasite in dogs in Sikkim (71.3%), Mumbai (48.8%) and Delhi (39.1%). In Ladakh, which experiences harsh extremes in climate, a competitive advantage was observed for parasites such as Sarcocystis spp. (44.2%), Taenia hydatigena (30.3%) and Echinococcus granulosus (2.3%) that utilise intermediate hosts for the completion of their life cycle. PCR identified Ancylostoma ceylanicum and Ancylostoma caninum to occur sympatrically, either as single or mixed infections in Sikkim (Northeast) and Mumbai (West). In Delhi, A. caninum was the only species identified in dogs, probably owing to its ability to evade unfavourable climatic conditions by undergoing arrested development in host tissue. The expansion of the known distribution of A. ceylanicum to the west, as far as Mumbai, justifies the renewed interest in this emerging zoonosis and advocates for its surveillance in future human parasite surveys. Of interest was the absence of Trichuris vulpis in dogs, in support of previous canine surveys in India. This study advocates the continuation of birth control programmes in stray dogs that will undoubtedly have spill-over effects on reducing the levels of environmental contamination with parasite stages. In particular, owners of pet animals exposed to these environments must be extra vigilant in ensuring their animals are regularly dewormed and maintaining strict standards of household and personal hygiene.
To estimate the current prevalence of gastrointestinal (GI) parasites in dogs and cats, a total of 105 fresh faecal samples were collected from rural areas in Peninsular Malaysia. Each faecal sample was examined for the presence of GI parasites by microscopic examination after formalin-ether concentration technique and for protozoa, trichrome and Ziehl-Neelsen staining were employed. The overall prevalence of GI parasitic infection was 88.6% (95% CI = 82.5-94.7) in which 88.3% of dogs and 89.3% of cats were infected with at least one parasites species, respectively. There were 14 different GI parasites species (nematodes, cestodes and protozoa) detected, including Ancylostoma spp. (62.9%), Toxocara spp. (32.4%), Trichuris vulpis (21.0%), Spirometra spp. (9.5%), Toxascaris leonina (5.7%), Dipylidium caninum (4.8%), Ascaris spp. (2.9%), Hymenolepis diminuta (1.0%) and others. General prevalence of GI parasites showed a significant difference between helminth (84.4%) and protozoa (34.3%) infections. Monoparasitism (38.1%) was less frequent than polyparasitism (46.7%). As several of these GI parasites are recognized as zoonotic agents, the results of this investigation revealed that local populations may be exposed to a broad spectrum of zoonotic agents by means of environmental contamination with dogs and cats faeces and this information should be used to mitigate public health risks. Prevention and control measures have to be taken in order to reduce the prevalence rates especially in socioeconomically disadvantaged communities where animals live in close proximity to people, poor levels of hygiene and overcrowding together with a lack in veterinary attention and zoonotic awareness.
Human filariasis caused by Brugia malayi is still a public health problem in many countries of Asia including India, Indonesia, Malaysia and Thailand. The World Health Organization (WHO) has targeted to eliminate filariasis by the year 2020 by Mass annual single dose Diethylcarbamazine Administration (MDA). Results of the MDA programme after the first phase was less satisfactory than expected. Malayan filariasis caused by B. malayi is endemic in the south of Thailand where domestic cat serves as the major reservoir host. There is no report about the occurrence of B. malayi in dogs. The present work was carried out to find out the incidence of microfilariasis in dogs and also to detect the presence of human filarial infection in dogs, if any. One hundred dogs above 6 months of age presented to the veterinary college Hospital, Mannuthy, Kerala, with clinical signs suggestive of microfilariasis - fever, anorexia, conjunctivitis, limb and scrotal oedema - were screened for microfilariae by wet film examination. Positive cases were subjected to Giemsa staining, histochemical staining and molecular techniques. Results of the study showed that 80% of dogs had microfilariasis; out of which 20% had sheathed microfilaria. Giemsa and histochemical staining character, PCR and sequencing confirmed it as B. malayi. High prevalence of B. malayi in dogs in this study emphasized the possible role of dogs in transmission of human filariasis.
The presence of rabies in dogs has been well recognized in areas of Malaysia close to the Thai border but it has rarely ever been reported in Terengganu which is a state on the East Coast of Malaysia. From November 1995 to June 1996 six different rabid stray dogs were found to have been involved in dog bite attacks on 9 members of the public. We report these cases to highlight that rabid dog bites may occur even in areas where the disease is thought to be rate. Medical and veterinary staff must keep the possibility of the risk of rabies in mind when faced with patients who have been bitten by dogs.
Between January 1987 and February 1990 Babesia infections were detected in 320 dogs in Germany by means of microscopical and/or serological methods. It was found, that 316 dogs were infected with Babesia canis and 4 animals with Babesia gibsoni. Of the Babesia-canis-positive dogs 184 were abroad up to 4 months before diagnosis, mainly in France, Spain and Italy, but also in Hungary, Greece, Jugoslavia, Portugal, Morocco, Togo, Pakistan, Sri Lanka, Malaysia, Turkey, Romania, Austria and the Netherlands. For further 36 dogs the possible place of infection for Babesia canis could not be clarified geographically. 5 dogs each were simultaneously infested with Rhipicephalus sanguineus and Dermacentor reticulatus, respectively. The four dogs infected with Babesia gibsoni were previously in Sri Lanka (2), Brazil (1) or Algeria/Kenya (1). In 88 dogs from the Offenburg/Lahr/Freiburg area, which were not abroad, infections with Babesia canis were diagnosed from January to June as well as from September to December, however, most cases occurring in April and May. Of these dogs approximately 20% were found to be infested with Dermacentor reticulatus. These ticks were also collected on the vegetation in the Offenburg area. Therefore, an endemic focus of Babesia canis can be deduced in the area of Offenburg/Lahr/Freiburg and Dermacentor reticulatus as vector also in Germany.
Filarial infections in 447 cats and 68 dogs from six endemic areas of human filariasis in Peninsular Malaysia were studied as part of the study on the zoonotic transmission of subperiodic Brugia malayi infection. 20.6% of cats and 57.4% of dogs had filarial infections. Cats were infected with subperiodic B. malayi, B. pahangi, Dirofilaria repens and D. immitis. Dogs were infected with B. pahangi and D. immitis. 6.9% of the cats had subperiodic B. malayi infection. The zoonotic implications of these infections and their impact on the filariasis control programme in Peninsular Malaysia were discussed.
This study was conducted to investigate the low prevalence of Dirofilaria immitis in dogs in Johor Bahru as reported by veterinary practitioners, using wet blood mount, Knott's Concentration Test and two heartworm antigen test kits (IDEXX Canine SNAP® 4Dx and RapiGEN®). This study also compared the two test kits used and determined the microfilaria species. Blood were collected from 100 owned dogs and 50 stray dogs in Johor Bahru via cephalic venipuncture. A thick blood smear was done and examined for samples that were positive for microfilaria species identification. The overall prevalence of D. immitis in dogs in Johor Bahru was 1.33% (2/150) and the microfilaria identified was D. immitis. The prevalence of heartworm in owned and stray dogs in this study was 1% and 2% respectively. With only one false negative result from RapiGEN® test kit, comparing the sensitivity between the two test kits could not be achieved. The low prevalence of D. immitis found in this study confirmed anecdotal evidence that prevalence of dirofilariasis is indeed low in Johor Bahru. Additionally, we speculate that dirofilariasis in dogs might be considered as an indicator of vector availability.
The Indirect Fluorescent Antibody Test (IFAT) and thin blood smears were conducted to establish the prevalence of Ehrlichia canis infection in dogs presented for treatment by pet owners at five private and one government veterinary clinic. Results showed that 15% of the dogs were positive for the parasite via IFAT, but none using blood smears. However, infected dogs did not show severe clinical symptoms of canine monocytic ehrlichiosis (CME).
Working dogs are canine animals that have been trained to assist human beings in carrying out various tasks. They help in guarding property, performing rescues, assisting the visually impaired or physically handicapped, searching for drugs, explosives, and others. Leptospirosis is one of the most widespread zoonotic diseases in the world and a commonly occurring disease of the tropics and subtropics. In Malaysia, all working dogs are normally vaccinated with serovars, Pomona, Icterohaemorrhagiae, Canicola, and Grippotyphosa based on protocols recommended from other countries. The duration of immunity in vaccinated dogs for Leptospira can last up to 13 months; however, there is no full crossprotection between the different serovars. Five representative canine units from different government agencies in Malaysia (n = 96 dogs) were recruited in this study. For detection, the microscopic agglutination test was performed by incubating the serum from dogs with various serovars of leptospires, namely, Icterohaemorrhagiae, Canicola, Pomona, Grippotyphosa, Australis, Bataviae, Javanica, Tarassovi, Hebdomadis, Lai, and Pyrogenes. The plasma obtained was used for polymerase chain reaction (PCR) analysis, for the detection of 16S rRNA, and lipL 32 genes of Leptospira. Out of the 96 dogs sampled, only 3 dogs were positive toward serovars, Australis, Bataviae, and Javanica, based on the cutoff point at 1:80. The seroprevalence of canine leptospirosis in this population was 3.1% (n = 3/96). However, all 96 blood samples of working dogs tested negative for both pathogenic and nonpathogenic Leptospira genes. The results revealed that, by vaccination alone, working dogs were not fully protected against leptospirosis and could pose a risk to dog handlers. A preventative and control protocol for leptospirosis is warranted, and its implementation should be monitored and improved accordingly from time to time, in order to maintain a healthy condition in both working dogs and their handlers.
This study determined the potential risk factors that may contribute to seropositivity among dogs and dog handlers from working dog and dog shelter institutions. Data was collected from dogs (n = 266) and dog handlers (n = 161) using a standardised guided questionnaire. Serum obtained from the dogs and dog handlers was tested using the microscopic agglutination test (MAT). A logistic regression analysis was used to predict leptospiral seropositivity of dogs and dog handlers based on potential risk factors. A total of 22.2% of dogs and 21.7% of dog handlers were seropositive. The significant predictors for the dogs' seropositivity were presence of rats (OR = 4.61 (95% CI: 1.05, 20.33), p = 0.043) and shared common area (OR = 5.12 (95% CI: 1.94, 13.46), p = 0.001) within the organisation. Significant predictor for dog handler seropositivity was contact time with the dogs of more than six hours/day (OR = 3.28 (95% CI: 1.28, 8.40), p = 0.013) after controlling for the effect of other risk factors such as small mammal contact, rat infestation at home, flooding at housing area (within three months) and urban locality. The exposure to various disease sources identified poses risk to dogs and dog handlers. Risk could be reduced with adequate application of protection at work while handling dogs and thus limiting contact with these sources and reducing exposure to infection.