Dirofilaria immitis infection in dogs in Algodoal Island, Brazilian Amazon / Infecção por Dirofilaria immitis em cães na Ilha de Algodoal, Amazônia brasileira

Dirofilaria immitis, a parasite that mainly infects domestic or wild canids, but can infect felines or humans as well, is frequent in many Brazilian areas. The main objective of this research was to determine the prevalence of natural canine infection at the Algodoal-Maiandeua Island complex, in the coastal region of the state of Pará, Brazil. A total of 67 dogs were sampled for blood microfilariae detection and for D. immitis DNA detection. Microfilaria and D. immitis DNA could be detected in 35.8% (24/67) of the animals. In one dog's sample no microfilariae were detected, but the PCR was positive, suggesting that either larvae recently were eliminated or adults died shortly before sample collecting. Therefore, it can be concluded that the occurrence of D. immitis is a health threat for domestic and wild canids at the Island of Algodoal, as well as for feline or human health.(AU)

Dirofilaria immitis, um parasito que infecta principalmente canídeos domésticos ou selvagens, embora também possa infectar felinos e humanos, é frequente em muitas áreas do Brasil. O objetivo deste estudo foi determinar a ocorrência da infecção natural em cães provenientes do complexo da Ilha de Algodoal-Maiandeua, região litorânea do estado do Pará, Brasil. Um total de 67 cães tiveram o sangue coletado para detecção de microfilárias de D. immitis e seu DNA. Microfilárias e o DNA de D. immitis foram detectados em 35,8% (24/67) dos animais. Na amostra de um animal, não foram observadas microfilárias, mas o seu DNA foi detectado, sugerindo que as larvas tenham sido recentemente eliminadas ou os adultos tenham morrido antes da coleta da amostra. Portanto, pode-se concluir que a ocorrência de D. immitis é uma ameaça à saúde de canídeos domésticos no complexo da Ilha de Algodoal-Maiandeua, bem como para felinos e seres humanos.(AU)

Update on Dirofilaria immitis epidemiology in South America and Mexico: literature review / Atualização sobre a epidemiologia de Dirofilaria immitis na América do Sul e no México: revisão de literatura

Dirofilaria immitis (Leidy, 1856; Raillet & Henry 1911) is a parasite that is widely disseminated around the globe, with a higher prevalence in warm, humid climates. The first report of its occurrence in South America is from 1878 in Brazil. At that time, reports were scarce and difficult to retrieve ­ therefore, gathering them will facilitate record-keeping over time. Four databases were searched (Scopus, MEDLINE, LILACS, and PubMed) and the search keywords were "Dirofilaria" or "heartworm" and the countries' names. Four countries lacked reports (Bolivia, Ecuador, French Guiana, and Uruguay) and other three (Suriname, Guyana, and Paraguay) had only old reports. Chile was the only country in which studies were conducted over time, and no infected dogs were registered. For the other six countries (Mexico, Peru, Colombia, Venezuela, Argentina, and Brazil), reports showed that the infection frequency varied over time and with the surveyed area. Therefore, the information indicates that D. immitis is established, and veterinarians must institute preventive programs to optimally care for their patients and protect the health of their families.(AU)

Dirofilaria immitis é um nematoide de ampla distribuição geográfica, que ocorre com maior frequência em áreas quentes e úmidas do planeta. O primeiro registro de sua ocorrência na América do Sul foi realizado em 1878, no Brasil. Naquela época os registros eram poucos e raramente de fácil obtenção, razão pela qual reuni-los facilitará a recuperação da memória ao longo dos anos. Quatro bases de dados (Scopus, MEDLINE, LILACS e PubMed) foram estudadas utilizando-se as palavras-chave "Dirofilaria" ou "heartworm", os nomes dos países da América do Sul e o México. Nenhum registro foi encontrado para quatro países (Bolívia, Equador, Guiana Francesa e Uruguai) e para outros três (Suriname, Guiana e Paraguai) os registros eram antigos. Apenas o Chile é o território onde houve estudos registrados com ausência do parasita. Os outros países (México, Peru, Colômbia, Venezuela, Argentina e Brasil) apresentam registros com frequência variável no tempo ou no espaço. Assim, as informações reunidas indicam que infecções por D. immitis ocorrem na maior parte da América do Sul e no México e que os médicos veterinários devem instituir programas preventivos para garantir cuidados médicos de qualidade aos pacientes e para proteger a saúde destes e de suas famílias.(AU)

Dirofilariasis involving the oral cavity: report of the first case from South America

Oral dirofilariasis is very rare with non-specific clinical manifestations. Here, we report the case of a 65-year-old South American woman with a submucosal nodule on her right buccal mucosa. The nodule was slightly tender and painful. Differential diagnoses included mesenchymal (lipoma or fibrolipoma, solitary fibrous tumor, and neurofibroma) or glandular benign tumors (pleomorphic adenoma) with secondary infections. We performed excisional biopsy. A histopathological examination revealed a dense fibrous capsule and a single female filarial worm showing double uterus appearance, neural plaque, well-developed musculature and intestinal apparatus. Dirofilariasis was diagnosed, and the patient was followed-up for 12 months without recurrence.

Prevalence of Dirofilaria immitis Infection in Stray Cats by Nested PCR in Korea

The purpose of this study was to conduct a survey of Dirofilaria immitis infection among stray cats in Korea using nested PCR. We included 235 stray cats (121 females and 114 males) and evaluated each for the presence of feline heartworm infection. Blood samples were collected from 135 cats in Daejeon, 50 cats in Seoul, and 50 cats from Gyeonggi-do (Province). Of the 235 DNA samples, 14 (6.0%) were positive for D. immitis. The prevalence of infection in male cats (8/114, 7.0%) tended to be higher than that in female cats (6/121, 5.0%), but the difference was not statistically significant. In each location, 8, 2, and 4 cats were positive for infection, respectively, based on DNA testing. No significant differences in the prevalence were observed among the geographic regions, although the rate of infection was higher in Gyeonggi-do (8.0%) than Daejeon (5.9%) and Seoul (4.0%). We submitted 7 of the 14 D. immitis DNA-positive samples for sequencing analysis. All samples corresponded to partial D. immitis cytochrome c oxidase subunit I gene sequences with 99% homology to the D. immitis sequence deposited in GenBank (accession no. FN391553). To the best of our knowledge, this is the first survey using nested PCR to analyze the prevalence of D. immitis in stray cats in Korea.

Canine heartworm disease in Porto Velho: first record, distribution map and occurrence of positive mosquitoes / Dirofilariose canina em Porto Velho: primeiro registro, mapa de distribuicao e ocorrencia de mosquitos positivos

The aim of this study was to make the first report on canine heartworm disease in the state of Rondônia and confirm its transmission in this state. Blood samples were randomly collected from 727 dogs in the city of Porto Velho. The samples were analyzed to search for microfilariae and circulating antigens, using three different techniques: optical microscopy on thick blood smears stained with Giemsa; immunochromatography; and PCR. Mosquitoes were collected inside and outside the homes of all the cases of positive dogs and were tested using PCR to search for DNA of Dirofilaria immitis. Ninety-three blood samples out of 727 (12.8%) were positive according to the immunoassay technique and none according to the thick smear method. Among the 93 positive dogs, 89 (95.7%) were born in Porto Velho. No difference in the frequency of infection was observed between dogs raised indoors and in the yard. PCR on the mosquitoes resulted in only one positive pool. This result shows that the transmission of canine heartworm disease is occurring in the city of Porto Velho and that there is moderate prevalence among the dogs. The techniques of immunochromatography and PCR were more effective for detecting canine heartworm than thick blood smears. The confirmation of canine heartworm disease transmission in Porto Velho places this disease in the ranking for differential diagnosis of pulmonary nodules in humans in Rondônia.

O objetivo deste estudo foi de registrar pela primeira vez a dirofilariose canina no estado de Rondônia e confirmar sua transmissão neste estado. Amostras de sangue de 727 cães foram colhidas aleatoriamente na cidade de Porto Velho. As amostras foram analisadas em busca de microfilárias e antígenos circulantes usando três técnicas diferentes: microscopia ótica de gota espessa corada com Giemsa e imunocromatografia de fluxo lateral e PCR. Mosquitos foram colhidos no domicilio e peridomicílio de todos os casos de cães positivos, estes mosquitos foram testados pela PCR na detecção de DNA de Dirofilaria immitis. Noventa e três das 727 amostras de sangue foram positivas na técnica de imunoensaio (12,8%). Nenhuma amostra foi positiva na gota espessa. Entre os 93 cães positivos, 89 (95,7%) foram nascidos em Porto Velho. Nenhuma diferença na frequencia de infecção foi observada entre cães criados dentro da casa ou no quintal. O PCR dos mosquitos resultou em apenas um pool positivo. Este resultado mostra que a transmissão de dirofilariose canina está ocorrendo na cidade de Porto Velho e a frequência que ocorre nos cães é considerada moderada. As técnicas de imunocromatografia e PCR são mais eficazes na detecção de dirofilariose comparadas a gota espessa. A confirmação de transmissão de dirofilariose canina em Porto Velho, coloca esta doença no ranking de diagnóstico diferencial de nódulos pulmonares em seres humanos em Rondônia.

Prevalence of Dirofilaria immitis in Dogs in Shenyang, Northeastern China

In the present study, we first report the seroprevalence of Dirofilaria immitis in dogs in Shenyang, northeastern China. Sera from 528 randomly selected dogs were examined for D. immitis antigen using SNAP(R)4Dx test kit; 12.7% tested showed seropositive. No significant difference of infection was observed in different genders and breeds (P>0.05), but the difference was significant in different age groups and rearing conditions (P<0.05). The result suggested that the risk of exposure to D. immitis in dogs is high in Shenyang, and should be given attention.

Dirofilariose humana em Joinville-SC: avaliação clinicopatológica dos primeiros casos relatados na região Sul / Human dirofilariasis in Joinville-SC: clinical-pathological assessment of the first cases reported in the Southern region

INTRODUÇÃO: Dirofilariose é uma zoonose rara causada pelo gênero Dirofilaria e acomete principalmente os pulmões, sendo capaz de simular neoplasia pulmonar. Pouca informação está disponível na literatura sobre a ocorrência e a distribuição de dirofilariose humana na América do Sul. Até 2004, haviam sido descritos apenas 50 casos de dirofilariose humana pulmonar no Brasil, sendo 37 apenas em São Paulo. OBJETIVO: Comprovar a existência de dirofilariose na região de Joinville-SC. MATERIAIS E MÉTODOS: Revisão de arquivos de laboratórios de anatomia patológica da cidade à procura de casos com os termos granuloma parasitário, helminto, helmintíase, verme, Dirofilaria e dirofilariose. Foram incluídos na pesquisa casos que satisfizeram os critérios para dirofilariose, segundo literatura específica. Os prontuários foram revisados e as amostras reprocessadas e analisadas histologicamente por seis colorações diferentes. RESULTADOS: Encontrou-se um caso em globo ocular e sete casos pulmonares, sendo o lobo inferior a localização preferencial (cinco casos). A análise microscópica revelou, nos casos pulmonares, nódulo bem delimitado, frequentemente centrado em uma artéria, com reação granulomatosa e necrose associada à fibrose e infiltrado inflamatório mono e polimorfonuclear, sendo possível identificar segmentos do parasita degenerado, compatível com Dirofilaria immitis. DISCUSSÃO: Todos os parasitas encontrados apresentam características morfológicas idênticas às relatadas na literatura para Dirofilaria immitis. A presença de D. immitis no globo ocular, como observada em um dos pacientes na presente revisão, é rara. CONCLUSÃO: A ocorrência de dirofilariose humana foi confirmada em Joinville e região, sendo causada pela Dirofilaria immitis.

INTRODUCTION: Dirofilariasis is a rare zoonosis caused by Dirofilaria genus, which affects mainly the lungs and may be misdiagnosed as lung cancer. Little information is available regarding the occurrence and distribution of human dirofilariasis in South America. Only 50 cases of human pulmonary dirofilariasis were described in Brazil until 2004, of which 37 were located in São Paulo. OBJECTIVE: To prove the existence of dirofilariasis in Joinville, SC. MATERIAL AND METHODS: The records of anatomic pathology laboratories of the city were reviewed in search for cases with the terms parasitic granuloma, helminth, helminthiasis, worm, Dirofilaria and dirofilariasis. According to specific literature, the cases that met the criteria for dirofilariasis were included in the study. The medical records were reviewed and the samples reprocessed and histologically analyzed by six different stains. RESULTS: We found one ocular case and seven pulmonary cases. The lower lobe was the main location (five cases). In all pulmonary cases, microscopic analysis revealed well defined nodules, frequently centered in a pulmonary artery, with granulomatous reaction and necrosis associated with fibrosis and mono and polymorphonuclear inflammatory infiltrate. It was also possible to identify segments of the deteriorated worm consistent with Dirofilaria immitis. DISCUSSION: All parasites found in this study show morphological characteristics similar to those reported in the literature on Dirofilaria immitis. The presence of D. immitis in the eye, as reported in one of the patients from this review, is rare. CONCLUSION: The occurrence of human dirofilariasis was confirmed in Joinville and region and it was caused by Dirofilaria immitis.

Identificación morfológica y molecular de filarías caninas en una comuna semi-rural de la Región Metropolitana, Chile / Morphological and molecular identification of canine filariae in a semi-rural district of the Metropolitan Region in Chile

Introduction: To date, there has been no definitive confirmation of the presence of zoonotic dirofilariasis in dogs in Chile. Objectives: To study the presence of dirofilarias in blood samples from dogs collected in a semi-rural district near Santiago and to compare their frequency in dogs with and without dermatological manifestations. Methods: We examined 100 blood samples for dog filariae infections using microscopic methods (modified Knott technique). 50 dogs presented dermatological symptoms or signs compatible with filarial infections and 50 were asymptomatic. ITS-2 and 12s rDNA gene amplification by PCR and sequencing were performed in samples microscopically positive for microfilariae. Results. We observed microfilariae in 22 dogs (22%). Of these, 16/50 (32%) were symptomatic and 6/50 (12%) were asymptomatic (p = 0.02). Morphologically, the majority of micro-filariae were similar to Dirofilaria repens, although many had a bigger size than previously described. Nucleotide sequencing of the amplified genes showed no more than 95% homology with the D. repens sequences available for comparison. D. reconditum and D. dracunculoides infections were also identified. Conclusions: These features might indicate the presence of new species of Dirofilaria or a D. repens close related variant in Chile.

Introducción: A la fecha no hay datos concluyentes en Chile respecto a la presencia de dirofilariasis zoonótica en perros. Objetivos: Identificar la presencia de dirofilarias en sangre de perros de una comuna semi-rural cercana a Santiago y comparar su frecuencia en animales con y sin manifestaciones dermatológicas. Materialy Métodos. Se examinó un frotis sanguíneo de 100 perros en busca de microfilarias mediante observación microscópica (técnica de Knott modificada). Cincuenta perros presentaban síntomas o signos dermatológicos que se han asociado a esta parasitosis y 50 eran asintomáticos. Se amplificaron los genes ITS-2 y 12s ADNr de filarías en las muestras con microfilarias al frotis, secuenciando los fragmentos amplificados. Resultados: Se observaron microfilarias en 22 perros (22%), 16/50 (32%) sintomáticos y 6/50 (12%) asintomáticos (p = 0,02). Morfológicamente, la mayoría de las microfilarias observadas fueron similares a D. repens; sin embargo, una gran proporción mostró un tamaño mayor al descrito para esta especie. Las secuencias nucleotídicas de los genes amplificados mostraron una homología no mayor al 95% con las secuencias de D. repens disponibles para comparación. Se identificaron además dos especies poco patógenas, D. reconditum por morfología y secuenciación genética y D. dracunculoides por morfología. Conclusiones: Los resultados indican la existencia de una nueva especie de Dirofilaria cercanamente relacionada a D. repens o de una variante de esta especie.

Diagnóstico de Dirofilaria immitis en el municipio Sucre, estado Sucre, Venezuela / Diagnosis of Dirofilaria immitis in the municipality of Sucre, Sucre state, Venezuela

La dirofilariasis es una patología parasitaria, causada por los nematodos Dirofilaria immitis y D. repens, principalmente. Mientras que D. immitis presenta distribución mundial, D. repens se extiende por el viejo mundo. Ambas especies afectan a caninos y felinos domésticos y salvajes, así como a humanos, por lo que es un problema de salud pública mundial. En este estudio se determinó la prevalencia de D. immitis, en caninos del municipio Sucre, estado Sucre, Venezuela. Se tomaron muestras sanguíneas a 138 caninos domésticos, mayores de seis meses, sin distinción de raza ni sexo, previo consentimiento informado por sus propietarios. El diagnóstico parasitológico de las microfilarias circulantes se realizó por examen directo y método de concentración Knott modificado; las características morfológicas fueron observadas en extendidos teñidos con Giemsa. Se utilizó un estuche comercial, para la captura de antígenos de excreción-secreción de D. immitis. De los 138 caninos estudiados, 12 casos positivos (8,7%) fueron detectados parasitológicamente, mientras que por el estuche comercial se detectaron antígenos en 20 caninos (14,5%), lo que demuestra que existe una dirofilariasis oculta en el 5,8% de los casos evaluados. Uno de los perros microfilarémicos, no presentó antígenos circulantes. La prevalencia de dirofilariasis en el municipio Sucre, estado Sucre fue de 15,2%. Este reporte de dirofilariasis canina en el municipio Sucre, representa un importante aporte en el levantamiento epidemiológico de la enfermedad. Futuros estudios permitirán evaluar el riesgo de infección de las personas que conviven con los perros con dirofilariasis.

Heartworm is a parasitic disease, caused by nematodes Dirofilaria immitis and D. repens, mainly. While D. immitis presents worldwide distribution, D. repens extends the old world. Both species affect canines and felines domestic and wild, as well as human, so it is a global public health problem. In this study we determined the prevalence of D. immitis in dogs in the municipality of Sucre, Sucre state, Venezuela. Blood samples were taken for 138 domestic dogs, over six months, regardless of race or sex, prior informed consent by their owners. The parasitological diagnosis of circulating microfilariae was done by direct examination and concentration method modified Knott, the morphological characteristics were observed in Giemsa-stained smears. We used a commercial kit, for the capture of excretory-secretory antigens of D. immitis. Of the 138 dogs studied, 12 cases (8.7%) were detected parasitologically, whereas the commercial kit antigens were detected in 20 dogs (14.5%), demonstrating that there is an occult infections in 5.8% of the cases. One of the dogs with microfilariae in blood, did not submit antigens circulating. The prevalence of heartworm in the municipality of Sucre, Sucre state was 15.2%. This report of canine heartworm in the municipality of Sucre, represents an important contribution in an epidemiologic survey of the disease. Future studies will assess the risk of infection for people living with dogs with heartworm disease.

Dirofilariose: zoonose emergente negligenciada: [revisão] / Dirofilariasis: neglected emerging zoonosis: [revision]

A dirofilariose é uma zoonose pouco conhecida causada por Dirofilaria spp., nematódeo mais conhecido como verme do coração dos cães (Dirofilaria immitis), parasita do sistema circulatório desses animais, mas que também pode acometer gatos e o ser humano. Sua ocorrência está intimamente ligada à presença de mosquitos vetores (Aedes spp., Anopheles spp., Culex spp.), condições climáticas favoráveis, assim como trânsito entre regiões indenes e endêmicas/epidêmicas. O ser humano pode se infectar com D. immitis (pulmão), Dirofilaria repens (pulmão, subcutâneo) e Dirofilaria tenuis (subcutâneo). A fisiopatologia está intimamente ligada à morte do parasita onde, no cão, pode induzir a obstrução de vasos circulatórios e no ser humano produzir uma lesão nodular com intensa reação inflamatória no parênquima pulmonar com formato de moeda observada nas radiografias. Pode ser diagnosticada pelo exame físico, pela detecção de microfilárias na circulação sangüínea, imunoadsorção enzimático (ELISA), alterações radiográficas, ecocardiografia, ultrassonografia e necropsia. Há riscos no tratamento, sendo a prevenção com a utilização de drogas nos animais o método mais eficaz, principalmente em visitas a áreas endêmicas ou epidêmicas, diminuindo-se, assim, o risco para saúde pública devido à disseminação do parasita.

Dirofilariasis is an unknown zoonosis, caused by Dirofilaria spp, nematodea most known as dog's heartworm (Dirofilaria immitis), which parasites the vascular system of these animals, but infects cats and human beings too. Its occurrence is highly linked to the presence of mosquitoes (Aedes spp., Anopheles spp., Culex spp.), adequate climatic conditions, as well as the transit between infection-free and endemic/epidemic regions. Human beings can be infected by D. immitis (lung), Dirofilaria repens (lung, subcutaneous) and Dirofilaria tenuis (subcutaneous). The physiopathology is highly dependent of the parasite death, inducing the obstruction of the vascular system in dogs and nodular lesions with intense inflammatory reaction in pulmonary parenchyma, like a coin lesion, observed in the radiographs. It can be diagnosed by physical examination, microfilarias detection on the vascular system, enzymatic immunoadsortion (ELISA), radiographic alterations, echocardiography, ultrasonography and necropsy. There are risks on treatment and drug prevention in animals is the most efficient method, mainly in visits to endemic or epidemic areas, decreasing the risk to public health due to the parasite dissemination.

Ocular dirofilariasis in Dubai, UAE.

A rare occurrence of ocular subconjunctival dirofilariasis in a 53-year-old healthy Indian male working in Dubai, UAE presenting with an acute red eye is reported. Surgical excision under topical anesthesia was carried out uneventfully in the outpatient clinic. The live worm removed from the subconjunctival space was identified as Dirofilaria repens on the basis of microscopic examination and histopathology. Surgical excision of subconjunctival dirofilariasis is safe in an outpatient setting and curative precluding the need for further systemic antihelminthics.

Prevalence of blood filaria in dogs in Golestan province [North of Iran] using modified knot method and determination of its periodicity

In the present study Blood was collected from dogs [n = 110] after clinical examinations and recording of necessary information [age, sex, breed and housing] examined by modified knott method. Periodicity of the microfilaria in peripheral blood circulation, was determined through blood collection from a dog each hour for 72 hours. Number of microfilaria in each ml of the blood samples was calculated and expressed as average of microfilaria in each hour. Results showed that 15.45% of dogs were infected by Dirofilaria immitis and 4.55% by Dipetalonema reconditum. Statistical analysis did not show significant relationship between infection and age, sex, breed and housing status. Furthermore, maximum and minimum numbers of microfilana were seen at 1 am [13316 microfilaria] 12 am [6681 microfilaria] respectively. Therefore, by considering the infection of dogs on Golestan province and its transmition to other animals, control of above-mentioned nematode should be done by treatment of infected dogs and eradicution of stray dogs

Focos de dirofilariose canina na Ilha do Marajó: um fator de risco para a saúde humana / Focus of canine heartworm disease in Marajó Island, North of Brazil: a risk factor for human health

A ocorrência de dirofilariose pulmonar humana relaciona-se com a prevalência de infecção por Dirofilaria immitis na população canina. Várias espécies de mosquitos são vetores desse nematóide. Analisaram-se amostras de sangue canino coletados nas vilas Pingo d'Agua e União, município de Salvaterra (Ilha do Marajó, PA), em junho, 2004 (n=34) e abril, 2005 (N=90). Os diagnósticos parasitológico e imunológico (ELISA - kit SNAP® 3DX™, Biobrasil) foram comparados (chi2, alfa=0,05) no exame de 34 amostras. A prevalência na população (N=90) foi avaliada pelo ELISA. O ELISA revelou mais positivos (25/34; 73,5 por cento) que a gota espessa (23/34, 67,6 por cento) e o Knott (21/34, 61,8 por cento), mas a diferença não foi significativa (p>0,05). A freqüência de infecção por D. immitis na faixa de 0 a 2 anos foi 58 por cento, enquanto em cães mais velhos foi 100 por cento. A prevalência da dirofilariose canina em Pingo d'Agua e Vila União foi alta (53,5 por cento), indicando risco de transmissão do parasito às pessoas nessa área.

The occurrence of human pulmonary dirofilariasis maintains a relation with the prevalence of Dirofilaria immitis infection in the canine population. Several mosquito species are vectors of this nematode. Canine blood samples collected in Pingo d'Agua and União villages, Salvaterra municipality (Marajó Island, Pará), in June, 2004 (n=34) and April, 2005 (N=90) were analyzed. Parasitological and immunological (ELISA - kit SNAP® 3DX™, Biobrasil) diagnoses were compared following the examination of 34 samples. The prevalence in the population (N=90) was evaluated by means of ELISA. ELISA revealed more positive samples (25/34; 73.5 percent) than thick smears (23/34, 67.6 percent) or Knott (21/34, 61.8 percent), but the differences were not significant (p>0.05). The frequency of D. immitis infection was 58 percent in dogs ranging from 0-2 years old, whereas in older dogs it was 100 percent. The prevalence of canine dirofilariasis was high in Pingo d'Agua and Vila União (53.5 percent), indicating the risk of parasite transmission to the people in this area.

Study of dirofilariasis in a selected area in the Western Province.

INTRODUCTION: Human dirofilariasis is a zoonotic infection caused by the filarial worm, Dirofilaria (Nochtiella) repens, whose primary host is the dog. This infection is on the increase over the past decade in Sri Lanka and the prevalence of canine dirofilariasis in the country is also believed to be high. We present here a study on public awareness of dirofilariasis and the prevalence of this infection in dogs in Negombo, an urban area that has a high domestic canine population. OBJECTIVE: To assess the awareness of dirofilariasis infection among residents and study the prevalence of this infection in domestic dogs in Negombo. DESIGN: Prospective study. SETTING: Department of Parasitology, Faculty of Medicine, University of Colombo, Colombo 8, Sri Lanka. METHODS: A descriptive cross-sectional study within the city of Negombo during September and November 2003 using a pre-tested, interviewer-administered questionnaire with cluster sampling was done. Two hundred seventy adults, including 132 dog owners, were included in the study. Data analysis was done using the Epilnfo programme. The prevalence of canine dirofilariasis was studied in a group of 65 dogs over the age of 1 year. They were selected by cluster sampling with random choice of the streets within the study area. Stained thick blood films, made following an earlobe-prick at any time during the day, were microscopically examined for the presence of microfilariae. RESULTS: Forty nine of the respondents (18%) were aware of the existence of canine dirofilariasis while human dirofilariasis was known only to 6%. Awareness was related to the level of education. Knowledge of canine filariasis was better among pet owners (32/132) when compared to others (18/138; p < 0.05). Veterinary surgeons were acknowledged as the source of information by 38% of those who were aware of the disease. Forty five per cent (n = 29) of the dogs screened were positive for microfilariae. Out of these 18 and two dogs were infected with D repens. and B. ceylonensis, respectively, while nine others were co-infected with the two parasites. CONCLUSIONS: The knowledge of dirofilariasis is extremely poor in the study area. The high prevalence of filarial infections in dogs highlights the importance of improving the public awareness of this disease, especially among the dog owners. Proper management of this condition in dogs-the reservoirs of infection for human dirofilariasis, is important for the control of this zoonotic infection.

Dirofilariosis in dogs and humans in Kerala.

There has been an increased occurrence of filarial worms in the subcutaneous tissues and subconjunctival space of human beings belonging to different areas of the state of Kerala. The present work was carried out to identify the worms recovered from human cases, to study the presence of microfilariae in dogs and to discuss the possible mode of infection in human beings. Twelve worm specimens from human patients received in the Department of Veterinary Parasitology, College of Veterinary and Animal Sciences, Mannuthy from 2002 to 2004 were identified as Dirofilaria repens based on morphology. Out of the 160 blood smears of dogs examined during the same period, microfilariae were detected in 11 samples (7%). With 7 per cent dogs positive for microfilariae of D. repens in Kerala, it is suggested that human beings are at an enhanced risk of acquiring dirofilaria infection.

Prevalence of Toxocara canis, Toxascaris leonina and Dirofilaria immitis in dogs in Chuncheon, Korea (2004)

The intestines and hearts of dogs were examined for Toxocara canis, Toxascaris leonina, and Dirofilaria immitis, after necropsy between June 26 and September 29, 2004 in Chuncheon, Korea. Of the 662 dogs examined, 6 were infected with T. canis (0.9%), 86 with T. leonina (13.0%). Fifty dogs were infected with D. immitis among 500 dogs examined (10.0%). Five were co-infected with T. canis and T. leonina, and three were co-infected with T. leonina and D. immitis. The cumulative positive infection rate for three species was 134/662 (20.2%). Considering previously reported seropositive rates of T. canis excretory-secretory antigen, i.e., 5% in the adult population in Korea, the possibility of toxocariasis caused by T. leonina should be reevaluated.

Subconjunctival dirofilariasis in India.

Human dirofilariasis caused by Dirofilaria repens, have been reported to occur widely throughout Asia, Europe and Africa. Reports of this infection from India are however limited. Herein we report a case of subconjunctival dirofilariasis from Karnataka state of India. A 42 year old man presented with a history of pain and swelling in the left eye. A live parasite measuring 3.5cm in length was surgically removed from the nodular swelling in the conjunctiva. The parasite was identified as Dirofilaria repens, adult male.

Mosquitos vetores potenciais da dirofilariose canina na Regiäo Nordeste do Brasil / Mosquitoes potential vectors of canine hearthworm in the Northeast Region from Brazil

Introduçäo: Em alguns bairros costeiros de Säo Luís, Maranhäo, a prevalência da dirofilariose chega a mais de 40 por cento entre os cäes domiciliados. Porém, desconhecem-se os vetores naturais, tanto lá quanto no resto do Nordeste do país. O objetivo do estudo foi identificar os prováveis vetores dessa parasitose. Métodos: Realizaram-se coletas mensais de mosquitos em um bairro costeiro de Säo Luís, MA, de março de 1996 a maio de 1997, no peridomicílio, tendo cäo e homem como iscas. Os mosquitos foram dissecados para a pesquisa de larvas da Dirofilaria immitis. Resultados: Coletaram-se 1.738 mosquitos de 11 espécies. Culex quinquefasciatus, capturada todos os meses, porém menos freqüente na estaçäo chuvosa, correspondeu a 54,5 por cento do total, seguido Aedes albopictus (20,3 por cento), Aedes taeniorhynchus e Aedes scapularis (ambos 11 por cento). Larvas de D. immitis foram encontradas em 0,1 por cento dos Cx. quinquefasciatus e 0,5 por cento dos Ae. taeniorhynchus. Ae. taeniorhynchus e Cx. quinquefasciatus foram considerados vetores potenciais da dirofilariose em Säo Luís. A importância local de Cx. quinquefasciatus como transmissor primário da D. immitis necessita ser melhor avaliada

Survey of canine heartworm in the city of Recife, Pernambuco, Brazil

Six hundred and eleven random-source dogs (338 male, 273 female) one year of age or older, from six sections of the city of Recife, Pernambuco, were examined antemortem for circulating microfilariae Dirofilaria immitis and Dipetalonema reconditum adult heartworm (D. immitis) antigen, and examined postmortem for adult heartworms. The prevalence of heartworm infection was 2.3 per cent (14/611), as determined by necropsy for adult worms, and 1 per cent (6/611) had circulating microfilariae of D. immitis; thus, 57.1 per cent of the heartworm-infected dogs had occult infections. The results of serological testing indicated that 1.3 per cent (8/611) of the dogs were positive for adult heartworm antigen. A total of 42 (6.9 per cent) of the dogs had microfilariae of D. reconditum; 40 of these had only D. reconditum and two additional dogs had microfilariae of both species, D. immitis and D. reconditum.