Transmission of Leishmania infantum by Rhipicephalus sanguineus (Acari: Ixodidae) in Dogs.

BACKGROUND: Rhipicephalus sanguineus is the most widely distributed tick in the world, which is partly due to its biological flexibility and the global distribution of its major host, the domestic dog. In Mediterranean region it could be principal reservoir host for Leishmania infantum, usually transmitted by the phlebotomine sand flies. In this study, we evaluated the vector potential of R. sanguineus in transmitting L. infantum to uninfected dogs. METHODS: During 2014, five dogs with clinical manifestations of canine visceral leishmaniasis (CVL), high anti-Leishmania antibody titers and tick infestation, were selected from CVL endemic areas (Tehran and Alborz provinces). At least, twenty live ticks were removed from each infected dog. After morphological identification, the ticks were divided into two groups; ticks belonging to the first group were dissected for parasitological examinations and semi-nested PCR assay, and those of the second group were selected for the transmission of CVL caused by L. infantum to uninfected dogs. Following tick infestation, all uninfected dogs were kept for 9 months and examined monthly for clinical and serological tests. RESULTS: Nearly, 67% of ticks were infected by L. infantum using the semi-nested PCR. All other parasitological tests of ticks were negative. Clinical examinations and serological tests of the investigated dogs revealed negative results. Nested-PCR test results performed on splenic biopsy samples of dogs were also negative. CONCLUSION: L. infantum-positive R. sanguineus ticks were unable to transfer L. infantum from infected dogs to healthy ones. The detection of L. infantum DNA in ticks collected from naturally infected dogs by semi-nested PCR does not prove their vectorial competence.

Feline leishmaniosis due to Leishmania infantum in Northwest Iran: The role of cats in endemic areas of visceral leishmaniosis.

Visceral leishmaniosis caused by Leishmania infantum (L. infantum) is an important zoonotic disease endemic in the Mediterranean region. Domestic dogs and other wild canines are the main reservoir hosts for the parasite, while domestic cats (Felis catus) may be carriers of L. infantum, and play a role as secondary reservoirs for the parasite. In the present study, serological (DAT), parasitological (microscopic smears and culture) and molecular methods (nested PCR) were used to evaluate infection with L. infantum in 103 stray cats collected from villages of Meshkin Shahr district, located in Ardabil province which is a well-known endemic region of human and canine visceral leishmaniosis in Iran. Overall, 25 out of 103 cats (24.27%) displayed anti-Leishmania antibodies with different titers. Amastigote forms of the parasite were detected in microscopic smears of the spleen of a cat with high anti-Leishmania antibodies using DAT. L. infantum was identified on microscopic slides by nested PCR, and the results were confirmed by sequence analysis. Based on the high rate of seropositive cats in this study, we conclude that cats may have an important role in the maintenance of L. infantum in the endemic areas of zoonotic visceral leishmaniosis in Iran.

Feline Dirofilariosis Due to Dirofilaria immitis in Meshkin Shahr District, Northwestern Iran.

BACKGROUND: Dirofilaria immitis is a common nematode of the cardiovascular system, which infects carnivores all over the world. The infection is prevalent in dogs, but in cats and human is rare. Dirofilariosis is transmitted by mosquitoes. Cats are accidental hosts and are naturally resistant to the infection, compared to the dogs. Mild infection can cause severe illness in cats and may lead to death, so it is clinically important to diagnose the disease. METHODS: In the present study, 103 stray cats were collected from Meshkin Shahr district, Aradabil Province, northwestern Iran that is an endemic area for canine dirofilariosis. Blood samples were prepared from the saphenous vein of each cat and were examined for the presence of microfilariae by the modified Knott test. RESULTS: A 2 yr old male cat (0.97%) was microfilaremic. The cat was subjected to necropsy and 4 adult D. immitis (2 male and 2 female worms) were found in the right ventricle of the heart. PCR was then carried out and D. immitis was confirmed. CONCLUSION: Cats and other carnivores in Meshkin Shahr district are at risk of infection due to the high activity of vectors in this climate and it is important to follow up the infection in this area.

Lack of effects of intramuscular medetomidine on intraocular pressure in clinically normal cats.

OBJECTIVES: This study aimed to determine the effects of intramuscular medetomidine on the results of tonometry in healthy cats. METHODS: Sixteen healthy cats were randomly divided into two groups of eight cats. The first group was sedated with intramuscular medetomidine alone (100 µg/kg) and the second group received only saline (0.5 ml/5 kg). Intraocular pressure (IOP) values were measured immediately before (T0) and after the injections at 15 mins (T15) and 25 mins (T25) in both groups. RESULTS: Sedation with medetomidine did not cause a statistically significant change in the mean IOP values. The pretreatment mean ± SD IOPs in the treatment and control groups were 16.2 ± 3.1 and 15.9 ± 4.0 mmHg, respectively. In the medetomidine group the mean ± SD IOPs at T15 and T25 were 16.1 ± 4.1 (P = 0.9) and 14.6 ± 2.2 (P = 0.1). CONCLUSIONS AND RELEVANCE: Based on this study in healthy cats, medetomidine may be a good choice as a sedative agent in uncooperative cats when IOP measurements are needed. Further investigations in cats with abnormal IOPs are warranted.

A survey of feline behavioral problems in Tehran.

Behavioral problems in cats have drawn more attention in recent years since they affect the cat-owner relationship. This study was designed to study the rate of cats with undesirable behaviors according to their owners. Frequency of behavioral problems in 167 cats attending Small Animal Hospital, Faculty of Veterinary Medicine, University of Tehran, was evaluated using a questionnaire. According to the results, 94.6% of owners reported that their cats have exhibited at least one undesirable behavior. Fearfulness, attention seeking, aggression towards other cats/people, scratching, and elimination problems were the most prevalent behavioral complaints reported by the owners; whereas obsessive behaviors were the least common behavioral complaints. In addition, data analysis suggested that age, breed, outdoor access, owner reaction towards the behavior and the cat's interaction with other cats/people might have been associated with the development of some behavioral problems in cats. Considerable rate of undesirable behaviors in domestic cats in Iran is important enough to highlight the significance of veterinary intervention.

Molecular and serological detection of Ehrlichia canis in naturally exposed dogs in Iran: an analysis on associated risk factors.

The general aim of this study, which was conducted for the first time in Iran, was to evaluate the seroprevalence and geographical distribution of Ehrlichia canis in a dog population in Iran, followed by molecular confirmation using PCR and sequencing. Blood samples were collected from 240 dogs in different areas of Alborz and Tehran Provinces and initially analyzed using the immunofluorescent antibody (IFA) test to detect anti-Ehrlichia canis IgG antibodies. Subsequently, nested PCR was performed based on a fragment of the 16S rRNA gene of E. canis on serologically positive samples. The results showed that 40/240 dogs (16.6%) presented anti-Ehrlichia canis IgG antibodies and that nine of the blood samples from the 40 seropositive dogs (22.5%) contained E. canis DNA, which was confirmed by sequencing. The seroprevalence of E. canis tended to be higher in purebred, one to three-year-old male dogs living in the Plain zone, in rural areas; however, this difference was not statistically significant.

Molecular and serological detection of Ehrlichia canis in naturally exposed dogs in Iran: an analysis on associated risk factors / Detecção molecular e sorológica de Ehrlichia canis em cães naturalmente expostos no Irã: uma análise dos fatores de risco associados

The general aim of this study, which was conducted for the first time in Iran, was to evaluate the seroprevalence and geographical distribution of Ehrlichia canis in a dog population in Iran, followed by molecular confirmation using PCR and sequencing. Blood samples were collected from 240 dogs in different areas of Alborz and Tehran Provinces and initially analyzed using the immunofluorescent antibody (IFA) test to detect anti-Ehrlichia canis IgG antibodies. Subsequently, nested PCR was performed based on a fragment of the 16S rRNA gene of E. canis on serologically positive samples. The results showed that 40/240 dogs (16.6%) presented anti-Ehrlichia canis IgG antibodies and that nine of the blood samples from the 40 seropositive dogs (22.5%) contained E. canis DNA, which was confirmed by sequencing. The seroprevalence of E. canis tended to be higher in purebred, one to three-year-old male dogs living in the Plain zone, in rural areas; however, this difference was not statistically significant.

O objetivo geral deste estudo, que foi feito pela primeira vez no Irã, foi avaliar a soroprevalência e distribuição geográfica de Ehrlichia canis em população de cães no Irã, seguida da confirmação molecular por meio de PCR seguida de sequenciamento. Amostras de sangue de 240 cães de diferentes áreas das Províncias de Alborz e Teerã foram coletadas e, inicialmente, analisadas pelo Reação de Imunofluorescência (IFA) para detecção de anticorpos IgG anti-Ehrlichia canis Subsequentemente, uma reação do tipo nested PCR baseada em um fragmento do gene 16S rRNA de E. canis foi realizada nas amostras sorologicamente positivas. Os resultados mostraram que 40/240 cães (16,6%) apresentaram anticorpos IgG anti- Ehrlichia canis e nove (22,5%) das amostras de sangue dos 40 cães soropositivos continham DNA de E. canis, confirmado por sequenciamento. A soroprevalência de E. canis, embora não estatisticamente significativa, mostrou uma tendência em se apresentar maior em cães machos com 1-3 anos, de raça pura, que vivem em zonas planas e áreas rurais.

Evaluation of a Novel Herbal Immunomodulator Drug (IMOD) in Treatment of Experimental Canine Visceral leishmaniasis.

Toxicity and drug resistance against pentavalent antimonials, medications of choice in treatment of leishmaniasis for more than 5 decades, have become important subjects globally. This study was a randomized, open labeled trial that was designed to determine efficacy and safety of IMOD as a novel herbal immunomodulator drug for treatment of canine visceral leishmaniasis (CVL). Twenty healthy mongrel dogs were infected with Iranian strain of L. Infantum amastigotes and randomly divided to 5 groups with four animals for each included on: I: negative control (non-infected) II: Glucantime® III: Glucantime® plus IMOD (immune-chemotherapy) IV: IMOD and V: positive control (non-treated). Physical examination, hematological, biochemical, serological, parasitological, pathological and imaging evaluations were performed pre-/post- interventions every month for 3 months. Comparing with control groups (I&V), immune-chemotherapy group (Glucantime® plus IMOD) showed significantly higher efficacy in resolving the clinical signs and hematobiochemistry factors. Based on our results, using IMOD in combination with meglumine antimoniate (Glucantime®) has significantly improved CVL than the latter drug alone. So, it seems this new herbal medicine is useful as adjuvant therapy for canine visceral leishmaniasis.

Assessment of the Effects of a Novel Herbal Immunomodulator Drug (IMOD) on Cytokine Profiles in Experimental Canine Visceral Leishmaniasis: a Preliminary Survey.

BACKGROUND: Cytokines play a fundamental role in the regulation of immune responses in remission and/or relapsing of leishmaniasis. Therefore, immunotherapy for the treatment of canine visceral leishmaniasis (CVL) has represented a principle approach in control of the infection. The present research aimed to evaluating the immunotherapeutic potential of a novel herbal immunomodulator drug (IMOD) on CVL. METHODS: Twelve mongrel dogs were intravenously infected with Iranian strain of L. infantum and randomly divided into three groups; 1: negative control (non-infected), 2: immunotherapy with IMOD and 3: positive control (non-treated). Cell proliferation and Th1-/Th2-type cytokines were measured in peripheral blood mononuclear cell (PBMC) by cell proliferation kit I (MTT) and enzyme-linked immunospot (ELISpot) assays, respectively. RESULTS: At the 60 days follow-up assessment, no adverse effects were observed in treated interventional group. Cellular proliferation assay indicated that PBMCs of IMOD group had higher stimulation index (SI) than positive control group (p < 0.05). Enhancement of CD4+T cells such as IL-2, IL-4 & IL-10 were detected in negative control group due to in vitro IMOD stimulation 30 days post-treatment. In accordance to decreasing trends of Th1 & Th2 cytokines in positive control group, the mean number of IFN-γ IL-2, IL-4 and IL-10 spot forming cells (SFCs) down regulated for IMOD group during the study. CONCLUSION: These data indicate that IMOD had immunomodulatory potential but is not sufficient for total parasitic cure due to balance of Th1/Th2 cytokines. This is a preliminary study and we propose to undertake a series of experiments to evaluate the CVL due to in vitro modulatory effects of IMOD.

Seroepidemiologic Survey of Canine Visceral Leishmaniasis in Tehran and Alborz Provinces of Iran.

BACKGROUND: A two year seroepidemiological study was designed to find out the seroprevalence and risk factors of canine visceral leishmaniasis (CVL) among stray and owned dogs in Tehran and Alborz Provinces of Iran. METHODS: Blood samples of 602 dogs living in 11 counties of Tehran and Alborz Provinces were taken by venipuncture in 2008-2010. After separation of blood sera, anti-leishmanial antibodies were detected by direct agglutination test (DAT). RESULTS: Overall, of the 408 and 194 serum samples collected randomly from dogs in 11 localities in Tehran and Alborz Provinces, 18/408 (4.41%) and 12/194 (6.18%) respectively were found positive. Among the localities, Shemiran in Tehran Province and Karaj In Alborz Province had the highest prevalence rates. No statistically significant differences were found between sex and living place but there was significant difference between living status (owned or stray) and CVL infection of dogs in Alborz Province (P= 0.018). The highest seroprevalence (7.5%) was found in dogs aged 3 to 5 years old. Only 20% of the seropositive dogs were symptomatic. CONCLUSION: Concerning possible human infections in Tehran and Alborz Provinces, both symptomatic and asymptomatic seropositive dogs should be considered as a risk.

An observational study on the current distribution of visceral leishmaniasis in different geographical zones of Iran and implication to health policy.

Visceral leishmaniasis is one of the most important parasitic diseases that is endemic in some parts of Iran. This study aimed to determine current distribution of visceral leishmaniasis in four distinct geographical zones of Iran. A cross-sectional study was conducted using direct agglutination test (DAT) on 9396 and 2559 serum samples collected from humans and domestic dogs, respectively during the period of 2007 through 2009. Altogether, 403 (4.3%) out of 9396 human serum samples collected from 4 distinct geographical locations showed anti-Leishmania antibodies with titers ≥ 1:3200. Physical examinations performed on 142 sero-positive cases with anti-Leishmania antibodies at titers of 1: 3200 to 1:102400 among whom fever (94.4%), paleness (67.6%) and hepato-splenomegaly (42.2%) were the predominant clinical signs and symptoms. The highest sero-prevalence rate (1.55%) was found in children ≤ 5 years old. Out of 2559 serum samples collected from domestic dogs, 212 (8.3%) were DAT positive (≥ 1:320). Leishmania infantum is the principal causative agent of the disease was isolated from both infected humans and dogs in Iran. Our findings indicate that Mediterranean visceral leishmaniasis with different distribution occurs in different geographical locations of Iran.

Effect of acepromazine or xylazine on tear production as measured by Schirmer tear test in normal cats.

OBJECTIVE: To evaluate the effect of acepromazine or xylazine on Schirmer tear test 1 results in clinically normal cats. ANIMALS: Sixteen healthy cross-breed cats. PROCEDURE: The animals were randomly divided into two groups of eight cats each. The first group was sedated with acepromazine alone (0.2 mg/kg) and the second group received only xylazine (2 mg/kg). All cats had Schirmer tear test (STT) readings taken prior to sedation and at 15 and 25 min postsedation. RESULTS: Sedation with acepromazine or xylazine in cats with normal pre-sedation STT 1 values caused a statistically significant decrease in mean values of tear production in both groups. In acepromazine group the mean +/- SEM STT at T(15) and T(25) were 4.31 +/- 0.98 (P < 0.001) and 5.18 +/- 1.07 (P = 0.002). The post-treatment mean +/- SEM values in xylazine group were 2.18 +/- 0.97 (P < 0.001) and 2.62 +/- 1.17 (P = 0.001) at 15 and 25 min respectively. Comparison between T(15) and T(25) in acepromazine group (P = 0.49) and xylazine group (P = 0.56) revealed no significant differences. CONCLUSION: These observations indicate that both acepromazine or xylazine significantly reduced tear production in clinically normal cats. In cats, clinicians should measure STT values prior to utilizing acepromazine or xylazine as sedatives in order to accurately assess the results. Moreover, sterile ocular lubricant or tear replacement should be used as a corneal protectant during sedation with these drugs.

Leptospira wolffii, a potential new pathogenic Leptospira species detected in human, sheep and dog.

Leptospirosis is the most common zoonotic disease, which is transmitted to humans through contaminated water or direct exposure to the urine of infected animals. In this study, the presence and prevalence of Leptospira species in the infected samples of human (n=369) and sheep (n=75) sera and also dogs' urine (n=150), collected from four provinces of Iran, were investigated by using nested-PCR/RFLP assay followed by sequencing analysis. Nested-PCR assay detected that 98/369 (26.5%) human, 13/75 (17.33%) of sheep's sera and 33/150 (22%) dogs' urine samples were positive for Leptospira DNA. RFLP assay detected that all positive cases had either pathogenic or intermediate Leptospira species. By sequence analysis, Leptospira interrogans was the most prevalent species among the examined samples of human (53/82, 64.6%) and sheep (11/13, 84.6%). However, in dog samples, Leptospira wolffii (27/29, 93.1%) was detected for the first time and was the dominant species. The presence of L. wolffii with 100% identity in clinical human samples and animals suspected with Leptospira may provide evidence for circulation of L. wolffii and its role in transmission cycle within human and animal hosts. In addition, this species can be potentially pathogenic to human and probably animal hosts. A large epidemiology survey would be needed to define the presence and the prevalence of this species in global endemic regions.