Immitis Infection Research Articles

Chemoprophylaxis of Dirofilaria immitis (Leidy 1856) infection at a high challenge environment.

BackgroundThe frequency of canine heartworm infection in the state of Rio de Janeiro, Brazil was high before chemoprophylactic treatment was available, with one of the highest rates of infection (52.5 %) found among dogs living on the eastern shore of the state. Following the launch of a chemoprophylactic product, the rate of infection gradually decreased, and new infections were rarely reported. After 2005, outbreaks reported at the eastern shore as well as for new infections in other areas of high infection frequency were considered to possibly be related to reduced efficacy of macrocyclic lactones. Therefore, this study aimed to evaluate the efficacy of topical heartworm preventatives from different drug families at the high challenge area of the state of Rio de Janeiro.MethodsA total of 46 dogs, including animals negative for Dirofilaria immitis microfilariae and antigen (Snap 4 Dx, IDEXX Laboratories, USA) at the initial screening were randomly allocated to two monthly treatment groups. Dogs in one group received topical moxidectin + imidacloprid and dogs in the other group received topical selamectin for eight consecutive months. Blood samples were obtained for microfilariae and antigen detection until the eleventh month after the first treatment. Dogs becoming microfilaremic or antigenemic on or before day 180 were considered to be infected prior to the first dose and were excluded from the study.ResultsA total of 29 dogs completed the study, including 14 treated with moxidectin + imidacloprid and 15 treated with selamectin. No dogs treated with moxidectin + imidacloprid (0/14) became infected during the treatment period, whereas four dogs of the selamectin group (4/15) became infected.ConclusionTopical moxidectin + imidacloprid is 100 % effective in preventing D. immitis infections in dogs living in a high challenge natural environment.

Detection of Dirofilaria immitis DNA in host serum by nested PCR.

The heartworm Dirofilaria immitis is the causative agent of dirofilariasis in dogs. Studies have shown that parasite-derived cell-free DNA (cfDNA) can be detected in host blood and may be a promising diagnostic marker for parasitic infections. Thus, our aim was to detect D. immitis-derived cfDNA in host serum by nested PCR. Sera were collected from 12 dogs with natural D. immitis infections; eight were microfilaria (mf)-positive, and the remaining four were mf-negative. Culture fluids derived from single-sex adult D. immitis worms (mf-producing females and males) were also tested for cfDNA. All mf-positive sera were positive by nested PCR, whereas no amplification products were detected in mf-negative sera. The culture fluid of mf-producing females was positive by nested PCR but that of males was negative. All products amplified by nested PCR were sequenced to confirm that the amplicons were those of D. immitis. These results indicate that D. immitis DNA circulates freely in dog serum, except in mf-negative dogs. Additionally, D. immitis cfDNA may primarily be derived from the mf, and adult worms appeared to be minor contributors of cfDNA concentrations in serum; however, the contribution of D. immitis cfDNA derived from larvae of other developmental stages is unclear. An evaluation of the kinetics of D. immitis cfDNA in host serum throughout the parasite life cycle could facilitate the development of early molecular diagnostic techniques. To the best of our knowledge, this is the first report of the detection of mitochondrial DNA from a filarial parasite in host serum.

Cold subcutaneous abscesses as the first manifestation of Coccidioides immitis infection in an immunocompromised host

Cold subcutaneous abscesses as the first manifestation of Coccidioides immitis infection in an immunocompromised host

Transient Glomerular Dysfunction in Dogs Caused by Dirofilaria immitis Infection

The present study aimed to examine two glomerular markers (urinary albumin, uALB; urinary C-reactive protein, uCRP) in healthy dogs and in dogs infected with Dirofilaria immitis, and to identify some possible changes in these markers after therapy with ivermectin and doxycycline. Twenty dogs with D. immitis infection positive by both the Knott method and SNAP 4Dx (IDEXX, USA) test were included in the research, as well as twelve clinically healthy dogs of similar age which served as controls. Glomerular biomarkers (meаn, SD) increased significantly in dogs with heartworm disease (uAlB/Creatinine, Cr mg/g: 527.57±312.54; uCRP/Cr mg/g: 0.520±0.624), compared to control dogs (uAlB/Cr mg/g: 94.44±56.50; uCRP/Cr mg/g: below detection limit). Six months after the initial examination and the simultaneous treatment, all glomerular markers were considerably decreased and did not differ from those in healthy animals. In conclusion, the observed changes in glomerular biomarkers clearly indicated the transient nature of glomerular dysfunction caused by the heartworm infection in dogs, which may be of clinical relevance.

Serological investigation of Leishmania infantum, Dirofilaria immitis and Angiostrongylus vasorum in dogs from southern Portugal.

BackgroundLeishmaniosis, dirofilariosis and angiostrongylosis are parasitic diseases of established importance in dogs worldwide. The aim of the present report was to determine all together levels of infection with or exposure to Leishmania infantum, Dirofilaria immitis and Angiostrongylus vasorum in dogs from the Algarve region, in southern Portugal.FindingsSerum samples were obtained from a total of 170 apparently healthy dogs. Antibodies to L. infantum were detected by the direct agglutination test; and antigens of D. immitis and of A. vasorum by an enzyme-linked immunosorbent assay and an immunochromatography test, respectively. Antibodies to L. infantum were found in 18.2% (31/170) of dogs, while D. immitis antigen was detected in 9.4% (16/170). None of 120 dogs tested out of the 170 under investigation had evidence of infection with A. vasorum. D. immitis infection was more prevalent in dogs aged 84–204 months than in those younger than 12 months. Three dogs were positive to both L. infantum and D. immitis.ConclusionsDogs living in southern Portugal are at risk of leishmaniosis and dirofilariosis. This scenario should make the veterinary community, local dog owners and also tourists from non-endemic countries coming on vacation with their pets aware of the need of effective prophylactic measures, in order to protect animals and public health.

Moxidectin steady state prior to inoculation protects cats from subsequent, repeated infection with Dirofilaria immitis.

BackgroundInfection of cats with Dirofilaria immitis causes seroconversion on antibody tests and pulmonary pathology, often without subsequent development of adult heartworms. Consistent administration of topical 10% imidacloprid-1% moxidectin has been shown to result in sustained plasma levels of moxidectin in cats after three to five treatments, a pharmacokinetic behavior known as “steady state”.MethodsTo evaluate the ability of moxidectin at “steady state” to protect cats from subsequent infection with D. immitis, cats (n = 10) were treated with the labeled dose of topical 10% imidacloprid-1% moxidectin for four monthly treatments. Each cat was inoculated with 25 third-stage larvae of D. immitis 7, 14, 21, and 28 days after the last treatment; non-treated cats (n = 9) were inoculated on the same days, serving as infection controls. Blood samples were collected from each cat from 1 month prior to treatment until 7 months after the final inoculation and tested for antibody to, and antigen and microfilaria of, D. immitis.ResultsMeasurement of serum levels of moxidectin confirmed steady state in treated cats. Cats treated with topical 10% imidacloprid-1% moxidectin prior to trickle inoculation of D. immitis L3 larvae throughout the 28 day post-treatment period remained negative on antibody and antigen tests throughout the study and did not develop gross or histologic lesions characteristic of heartworm infection. A majority of non-treated cats tested antibody positive by 3–4 months post infection (6/9) and, after heat treatment, tested antigen positive by 6–7 months post-infection (5/9). Histologic lesions characteristic of D. immitis infection, including intimal and medial thickening of the pulmonary artery, were present in every cat with D. immitis antibodies (6/6), although adult D. immitis were confirmed in only 5/6 antibody-positive cats at necropsy. Microfilariae were not detected at any time.ConclusionsTaken together, these data indicate that prior treatment with 10% imidacloprid-1% moxidectin protected cats from subsequent infection with D. immitis for 28 days, preventing both formation of a detectable antibody response and development of pulmonary lesions by either immature stages of D. immitis or young adult heartworms.

Survey of canine tick-borne diseases in Lábrea, Brazilian Amazon: ‘accidental’ findings of Dirofilaria immitis infection

Blood samples were collected from 99 domestic dogs from the urban and rural areas of the Lábrea municipality, state of Amazonas, Brazil. Canine serum samples were tested by immunofluorescence assay against Rickettsia spp., which revealed that only 3.0% (1/33) and 7.6% (5/66) of the dogs from urban and rural areas, respectively, reacted positively to at least one Rickettsia species. DNA was extracted from canine blood and tested by a battery of PCR assays targeting protozoa of the genera Babesia and Hepatozoon, and bacteria of the genera Rickettsia and Ehrlichia and family Anaplasmataceae. All samples were negative in the PCR assays targeting the genera Babesia, Hepatozoon, Ehrlichia and Rickettsia. For Anaplasmataceae, 3% (1/33) and 39.4% (26/66) of the urban and rural dogs, respectively, yielded amplicons that generated DNA sequences 100% identical to the corresponding sequence of Wolbachia endosymbiont of Dirofilaria immitis. Because of these results, all canine DNA samples were further tested in a PCR assay targeting filarial nematodes, which was positive for 18.2% (6/33) and 57.6% (38/66) urban and rural dogs, respectively. Filarial-PCR products generated DNA sequences 100% identical to D. immitis. While tick-borne infections were rare in Lábrea, D. immitis infection rates were among the highest reported in South America.

Concurrent transcriptional profiling of Dirofilaria immitis and its Wolbachia endosymbiont throughout the nematode life cycle reveals coordinated gene expression.

BackgroundDirofilaria immitis, or canine heartworm, is a filarial nematode parasite that infects dogs and other mammals worldwide. Current disease control relies on regular administration of anthelmintic preventives, however, relatively poor compliance and evidence of developing drug resistance could warrant alternative measures against D. immitis and related human filarial infections be taken. As with many other filarial nematodes, D. immitis contains Wolbachia, an obligate bacterial endosymbiont thought to be involved in providing certain critical metabolites to the nematode. Correlations between nematode and Wolbachia transcriptomes during development have not been examined. Therefore, we detailed the developmental transcriptome of both D. immitis and its Wolbachia (wDi) in order to gain a better understanding of parasite-endosymbiont interactions throughout the nematode life cycle.ResultsOver 215 million single-end 50 bp reads were generated from total RNA from D. immitis adult males and females, microfilariae (mf) and third and fourth-stage larvae (L3 and L4). We critically evaluated the transcriptomes of the various life cycle stages to reveal sex-biased transcriptional patterns, as well as transcriptional differences between larval stages that may be involved in larval maturation. Hierarchical clustering revealed both D. immitis and wDi transcriptional activity in the L3 stage is clearly distinct from other life cycle stages. Interestingly, a large proportion of both D. immitis and wDi genes display microfilarial-biased transcriptional patterns. Concurrent transcriptome sequencing identified potential molecular interactions between parasite and endosymbiont that are more prominent during certain life cycle stages. In support of metabolite provisioning between filarial nematodes and Wolbachia, the synthesis of the critical metabolite, heme, by wDi appears to be synchronized in a stage-specific manner (mf-specific) with the production of heme-binding proteins in D. immitis.ConclusionsOur integrated transcriptomic study has highlighted interesting correlations between Wolbachia and D. immitis transcription throughout the life cycle and provided a resource that may be used for the development of novel intervention strategies, not only for the treatment and prevention of D. immitis infections, but of other closely related human parasites as well.Electronic supplementary materialThe online version of this article (doi:10.1186/1471-2164-15-1041) contains supplementary material, which is available to authorized users.

Establishment of macrocyclic lactone resistant Dirofilaria immitis isolates in experimentally infected laboratory dogs.

BackgroundStrains of Dirofilaria immitis suspected of lack of efficacy (LOE) to macrocyclic lactone (ML) preventive drugs have been increasingly reported in dogs by practicing veterinarians since 2005 in the Lower Mississippi Delta region. If proven, and not controlled in the early stages, the emergence of ML drug resistance threatens to become a widespread problem in the US that may limit the effectiveness of current preventive drug treatment methods.MethodsTo validate practice reports, a statewide survey of Louisiana veterinarians was done to define the extent of the problem and identify focal ‘hotspots’ of reported ML LOEs using Geographic Information Systems (GIS) methods. The present study then utilized microfilariae (Mf) from two canine field cases from different state locations that fit criteria for a high index of suspicion of LOE against heartworms by ML drugs. Blood containing Mf from the canine field cases was used to infect and produce L3 in Aedes aegypti for experimental infection of two groups of dogs, each of which contained two laboratory dogs, one treated with prophylactic ivermectin (12 μg/kg) monthly for 6 months at twice the label dose (6 μg/kg), and one untreated control.ResultsBoth treated and untreated dogs from Group I and Group II developed patent D. immitis infections by 218 DPI and 189 DPI, respectively, as evidenced by a positive occult heartworm antigen test and microfilaremia by the Knott’s test. Mf counts gradually increased post-patency in test and control dogs. Infective larvae raised from microfilariae from the treated Group I dog were used to successfully establish a second generation isolate, confirming heritability of resistance in the face of a monthly ivermectin challenge dose of 24 μg/kg, given monthly for 3 months.ConclusionsThese experimental infection studies provide in vivo evidence of the existence of ML drug resistance in dogs infected by D. immitis L3 from suspect field LOE cases in the Lower Mississippi Delta. Results encourage further work on mechanisms underlying the emergence of ML resistance in D. immitis and development of evidence-based resistance management strategies for heartworm preventives in order to extend the useful life of current drugs.

Safety of concurrent treatment of dogs with fluralaner (Bravecto™) and milbemycin oxime-praziquantel.

BackgroundFluralaner (Bravecto™; Merck/MSD Animal Health) is a novel systemic ectoparasiticide for dogs providing long-acting flea and tick control after a single oral dose. Milbemycin oxime and praziquantel are routinely used to control Dirofilaria immitis and intestinal worm infections in dogs. The safety of concurrent use of fluralaner and a commercially available milbemycin oxime plus praziquantel combination tablet, in particular with regard to gastrointestinal symptoms, was investigated using oral doses at or above the maximum recommended rates.FindingsSome minor and transient clinical findings were observed during the study period; however, none of these was considered to be related to concurrent treatment with fluralaner and milbemycin oxime plus praziquantel, or to the use of either product alone.ConclusionsConcurrent treatment with fluralaner, milbemycin oxime and praziquantel is well tolerated in dogs.

서울지역 동물보호소 내 유기견의 개 심장사상충 감염 실태조사

Dirofilaria immitis infection is one of the most important parasitic diseases in dogs and public health. It often elicits nodules in the pulmonary parenchyma and in the subcutaneous tissues of human. In this study, we investigated the prevalence of D. immitis infection among 754 dogs in Seoul area from April to December 2012. The infection rate of 754 dogs was 9.8% (74/754) by the antigen test (canine SNAP 4Dx). The infection rates of D. immitis in dogs at the age of 10 years were 3.7% (7/189), 12.9% (30/233), 15.0% (19/127), 9.8% (18/184), and 0% (0/21), respectively. The infection rates in the female and male dogs were 9.7% (33/340) and 9.9% (41/414), respectively. The regional infection rates in northern and southern Han river region of Seoul were 10.7% (44/410) and 8.7% (30/344), respectively. In order to confirm D. immitis infection, we performed PCR on serum samples of 74 dogs which tested positive for D. immitis antigen by the antigen test and we detected a specific gene ITS-2 in 59 serum samples. In conclusion, this study suggests that treatment and preventive care on the D. immitis infection should be considered in dogs of Seoul area.

Right Pulmonary Artery Distensibility Index (RPAD Index). A field study of an echocardiographic method to detect early development of pulmonary hypertension and its severity even in the absence of regurgitant jets for Doppler evaluation in heartworm-infected dogs

Despite the term “heartworm disease” Dirofilaria immitis infection in dogs should be considered a pulmonary arterial disease that might only involve the right heart structures in its late stage. Chronic infection by adult heartworms in dogs results in proliferative endoarteritis leading to progressively increasing pulmonary artery pressure due to reduced elasticity. Elasticity allows the pulmonary arteries to stretch in response to each pulse and helps maintain a relatively constant pressure in the arteries despite the pulsating nature of the blood flow. Pulmonary artery distensibility for both acute and chronic pulmonary hypertension has been investigated in humans using MRI and has been correlated with the severity of hypertension and its outcome and treatment response. The aim of the present study was to investigate whether echocardiographic measurement of the percentage change in diameter of the right pulmonary artery in systole and diastole (distensibility) may be of value in assessing the presence and severity of pulmonary hypertension in heartworm-infected dogs. The Right Pulmonary Artery Distensibility Index (RPAD Index) (which is calculated as the difference in diameter of the right pulmonary artery in systole and diastole) was calculated in healthy and naturally infected heartworm-positive dogs. The right pulmonary artery was chosen because it is usually affected earlier and to a greater degree. Data were obtained from healthy heartworm-free dogs without any clinical, radiographic, or echocardiographic signs of pulmonary hypertension; naturally infected heartworm-positive dogs in different stages of the disease in which pulmonary pressure could be measured by Doppler echocardiography (using tricuspid and or pulmonary regurgitation velocity and pressure gradient); and naturally infected heartworm-positive dogs in different stages of the disease (with or without tricuspid and or pulmonary regurgitation) in which the pulmonary pressure was measured invasively and noninvasively if possible. Results of these evaluations indicated that RPAD Index is a valuable method for early detection of the presence and severity of pulmonary hypertension in heartworm-infected dogs even in the absence of regurgitant jets for Doppler evaluation and that there is a strong correlation between the RPAD Index and the level of pulmonary hypertension.

Experimental Dirofilaria immitis infection in dogs: Effects of doxycycline and Advantage Multi® administration on immature adult parasites

To better understand the efficacy of doxycycline and 10% imidacloprid+2.5% moxidectin (Advantage Multi®; Bayer Animal Health, Shawnee Mission, Kansas) on immature adult Dirofilaria immitis parasites and the results of antigen tests, 12 healthy, randomly selected dogs were experimentally infected with D. immitis and monitored for 407 days. Two dogs in each of three subgroups of four dogs were each infected with six (total of 6 dogs) or 12 (total of 6 dogs) D. immitis infective third-stage larvae (L3) obtained from infected mosquitoes. Doxycycline (10mg/kg per os twice daily×30 days) and 10% imidacloprid+2.5% moxidectin (1ml/kg by topical application every 30 days) treatment was initiated at 105 (Group A) and 149 (Group B) days post infection (PI) in two groups. One subgroup of two dogs given 6 L3 and one subgroup of two dogs given 12 L3 remained as untreated controls (GroupC). Serum obtained regularly throughout the study was evaluated by ELISA (PetChek® Heartworm-PF Antigen Test, IDEXX Laboratories, Inc.) for D. immitis adult circulating antigens. Six of the eight dogs in the treated groups had detectable antigenemia starting between 148 and 240 days post infection, but antigen was not detected in any treated dog at the end of the study. In the control subgroups, the dogs that received 6 L3 had no detectable antigen while the two dogs that received 12 L3 had detectable antigen beginning on Day 180 that persisted until the end of the study. None of the infected dogs had evidence of circulating microfilariae. At necropsy, no heartworms were recovered from the treated dogs, but all dogs in the untreated group had viable adult heartworms. These results indicate that early immature adult worms (3.5 and 5 months of age) of D. immitis were susceptible to a combined treatment regimen of doxycycline and 10% imidacloprid+2.5% moxidectin.

Expression of Translationally Controlled Tumor Protein (TCTP) Gene of Dirofilaria immitis Guided by Transcriptomic Screening

Dirofilaria immitis (heartworm) infections affect domestic dogs, cats, and various wild mammals with increasing incidence in temperate and tropical areas. More sensitive antibody detection methodologies are required to diagnose asymptomatic dirofilariasis with low worm burdens. Applying current transcriptomic technologies would be useful to discover potential diagnostic markers for D. immitis infection. A filarial homologue of the mammalian translationally controlled tumor protein (TCTP) was initially identified by screening the assembled transcriptome of D. immitis (DiTCTP). A BLAST analysis suggested that the DiTCTP gene shared the highest similarity with TCTP from Loa loa at protein level (97%). A histidine-tagged recombinant DiTCTP protein (rDiTCTP) of 40 kDa expressed in Escherichia coli BL21 (DE3) showed immunoreactivity with serum from a dog experimentally infected with heartworms. Localization studies illustrated the ubiquitous presence of rDiTCTP protein in the lateral hypodermal chords, dorsal hypodermal chord, muscle, intestine, and uterus in female adult worms. Further studies on D. immitis-derived TCTP are warranted to assess whether this filarial protein could be used for a diagnostic purpose.

Seroprevalence of vector borne parasites in naturally exposed dogs of Assam, India

Aim: To determine the seroprevalence of vector(tick)-borne Babesia canis, Babesia gibsoni, Ehrlichia canis and Borrelia burgdorferi and mosquito-borne Dirofilaria immitis in naturally exposed pet, working, and street dogs in Assam, India. Materials and Methods: Seroprevalence of B. canis and B. gibsoni was determined using Indirect Fluorescent Antibody Test (IFAT) kit and for D. immitis, E. canis and B. burgdorferi by Enzyme Linked Immunosorbent Assay (ELISA) in SNAP 3DX kit. The results along with blood microscopy findings were analyzed according to different categories of dogs. Results: The present study revealed the presence of Babesia canis, Babesia gibsoni, Dirofilaria immitis, and Ehrlichia canis usually in mixed infections. Seropositivity against B. gibsoni and B. canis in IFAT was found comparatively higher in hospital dogs (84.0% and 22.0%) than the street dogs (73.3% and 10%), whereas evidence of D. immitis infection in SNAP 3DX ELISA was found higher in street dogs (37.5%) than the hospital group (10%). Antibody to E. canis was detected in hospital dogs (32.0%) only and none of the dogs was found positive for Borrelia burgdorferi in the same ELISA kit. Besides detection of B. canis, B. gibsoni, D. immitis and E. canis in single or mixed infections, Hepatozoon canis and Anaplasma platys were also recorded in 2.0% and 8.0% respectively in hospital dogs and 3.33% and 6.66% in street dogs during microscopic examination of blood. Conclusion: High seroprevalence supported by microscopic findings indicate a very strong influence of ticks and mosquitoes as competent vectors in establishing an endemic situation for different species of Babesia, Dirofilaria and Ehrlichia.

Epidemiological aspects of Dirofilaria immitis infection in dogs from Assam of Northeast India

ObjectiveTo analyze the epidemiology of Dirofilaria immitis (D. immitis) infection in different categories of dogs in Assam. MethodsMicroscopy of blood in wet film preparation was conducted in two dog populations during 2009 and 2010, and data obtained were analyzed to investigate the infection pattern according to season, living condition, breed, sex and age of dogs. ResultsExamination of 424 clinically ill dogs (hospital population) presented at the referral Teaching Veterinary Clinical Complex, Guwahati, Assam revealed 5.42% cases microfilaraemic. Clinical cases of D. immitis infection were recorded throughout the year with 9.10% as the highest record during pre-monsoon and 1.12% as the lowest in the winter. Pet dogs staying indoor showed 4.76% microfilaria positive compared to 7.95% record among working dogs with restricted outdoor activity. Breed wise, Dalmatian dogs representing 3.53% of the study population were negative to microfilaria while among the positives, Doberman showed 30.76% infection rate as the highest and 2.94% lowest record in the Labrador. Rate of infection was slightly higher in the males (5.81%) than the females (4.81%). Dogs below 2 years of age were negative to microfilaria while it was 3.70% in 2–4 years age group with a rising trend reaching 28.00% as the highest in 6–8 years age group. Examination of non-descript (street dog population) adult dogs living outdoor showed 29.54% microfilaraemic, the rate of infection being higher in males (37.50%) than the females (25.00%). Similar non-descript dogs living indoor as pets however showed only 11.11% microfilaria positive. ConclusionsThe study shows endemicity of D. immitis in dogs of Assam with living condition and age as the host related important risk factors, which have significant role in its epidemiology.

Prevalence ofDirofilaria immitisamong shelter dogs in Tokyo, Japan, after a decade: comparison of 1999–2001 and 2009–2011

Changes in the seroprevalence of Dirofilaria immitis infection among shelter dogs between a decade ago and the present were evaluated. Serum samples were collected from 200 adult dogs in urban and suburban areas in Tokyo, Japan, during two 2-year periods (April 1999 to March 2001 and April 2009 to March 2011). Sera were tested for the presence of D. immitis antigen using a specific commercialized kit. The seroprevalence of D. immitis infection was 46% in 1999–2001 and 23% in 2009–2011. A decrease was observed in the prevalence of infection between 1999–2001 and 2009–2011; in particular, the prevalence in urban areas decreased significantly compared with that in suburban areas (P < 0.01). There was no significant difference in prevalence between the sexes in each period, but there was a significant difference between mixed-breed and purebred dogs (P < 0.01). The decrease in prevalence of canine heartworm disease in urban areas could be related to better veterinary care.

Safety of concurrent treatment of dogs with fluralaner (Bravecto¿) and milbemycin oxime - praziquantel

BackgroundFluralaner (Bravecto™; Merck/MSD Animal Health) is a novel systemic ectoparasiticide for dogs providing long-acting flea and tick control after a single oral dose. Milbemycin oxime and praziquantel are routinely used to control Dirofilaria immitis and intestinal worm infections in dogs. The safety of concurrent use of fluralaner and a commercially available milbemycin oxime plus praziquantel combination tablet, in particular with regard to gastrointestinal symptoms, was investigated using oral doses at or above the maximum recommended rates.FindingsSome minor and transient clinical findings were observed during the study period; however, none of these was considered to be related to concurrent treatment with fluralaner and milbemycin oxime plus praziquantel, or to the use of either product alone.ConclusionsConcurrent treatment with fluralaner, milbemycin oxime and praziquantel is well tolerated in dogs.

Prevalence of canine heartworm (Dirofilaria immitis) disease in dogs of central Portugal

The aim of the present study was to determine the prevalence and risk factors concerning Dirofilaria immitis infection in dogs from Figueira da Foz, located in the central region of Portugal. In the period between November 2009 and January 2011, 304 blood samples were obtained from dogs over 1 year of age, with no previous history of heartworm prevention or diagnosis. Every blood sample was analyzed using varied laboratory techniques (direct microscopic evaluation of a fresh blood sample, the modified Knott technique, and the ELISA antigen detection test – IDEXX Snapp®). In the samples in which microfilaremia was detected, a histochemical technique using acid phosphatase staining was applied to identify the species of microfilariae. A total prevalence of 27.3% (83 out of 304) was found. We also found that 73.5% of all positive cases (61 out of 83) were microfilaremic, and 26.5% were occult infections (22 out of 83). By means of a histochemical technique Dirofilaria immitis was identified in 96.7% of microfilaremic samples. A multivariate model allowed us to identify the following risk factors for the presence of heartworm disease: age between 4 and 9 years, dogs living in a rural environment, large breed dogs, and living outdoors. This study shows for the first time the high prevalence of heartworm disease in a central area of Portugal and emphasizes the importance of systematic screening for this disease, as well as the need to prevent it in dogs in this area.

진돗개의 심장사상충 감염률 조사

A survey of canine heartworm (Dirofilaria immitis) infection among 102 Jindo dogs was performed from September to October 1995, using a microfilarial test (modified Knott's test) and an antigen test (DiroCHEK, Synbiotics, USA). The infection rate of 102 Jindo dogs was 1.9% (2/102) by the modified Knott's test, but was 4.9% (5/102) by the antigen test. This result revealed that the antigen test is more accurate than the microfilarial test. Also, 222 Jindo dogs (Male 61, Female 161) were examined for Dirofilaria immitis infection from 1995 to 1997 using an antigen test (DiroCHEK, Synbiotics, USA). Twelve (5.4%) Jindo dogs were positive for Dirofilaria immitis antigen. The infection rates were higher than in male (6.6%, 4/61) than female dogs (5.0%, 8/161). The infection rates of heartworm in Jindo dogs at the age of under 1 year, 1~2 years and over 2 years old were 0.0% (0/39), 4.3% (5/115) and 10.3% (7/68), respectively. The older age had higher infection rates than the younger age (P=0.018). The infection rates of canine heartworm was reported to be the highest (17.6%, P=0.028) in Jodo-myeon, 10.6% in Uisin-myeon and 5.3% in limhoe-myun. But dogs with antigenemia weren't detected in Gogun-myeon. and Jisan-myeon. This study indicates that the prevalence of canine heartworm in Jindo-gun is lower than previously reported (3.1% and 12.3%) which utilized microfilarial tests.