Atualização sobre a epidemiologia de Dirofilaria immitis na América do Sul e no México: revisão de literatura

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.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

Soroprevalência da infecção por Toxoplasma gondii (Nicole & Manceaux, 1909) e a infecção por retrovírus em população urbana de gatos domésticos (Felis catus, Linnaeus, 1758) no Rio de Janeiro, Brazil

Cats, as definitive host, play an important role in the transmission of Toxoplasma gondii. This study aimed to establish the seroprevalence of anti-T. gondii immunoglobulins G and M, and determine the frequency of oocysts in the feces of the domestic cat population in Rio de Janeiro, Brazil. We also aimed to study the association between T. gondii infection and age, sex, breed, lifestyle, diet and retroviral infection. A total of 108 cats were included in the study and fecal samples of 54 of those cats were obtained. Only 5.6% of the cats were seropositive for anti-T. gondii immunoglobulins using the indirect hemagglutination test. None of the 54 cats presented oocysts in their fecal samples. Although not statistically significant, males, mixed-breed, free-roaming and cats aged two years and older were found to be more exposed. Age, lifestyle and the use of litter boxes were found to play an important role as risk factors. Anemia and retroviral infections were independent of T. gondii infection. No antibodies were detected in the majority of cats (94.4%), indicating that those cats had never been exposed to the parasite and, therefore, once infected, they could present the risk of shedding large numbers of oocysts into the environment.Os gatos, como hospedeiros definitivos, apresentam um papel fundamental na transmissão do Toxoplasma gondii. Nosso estudo teve como objetivo determinar a presença de imunoglobulinas G e M anti-T. gondii, e a frequência de oocistos nas fezes de uma população de gatos domésticos do Rio de Janeiro, Brasil. Objetivou-se ainda estudar a associação da infecção por T. gondii com a idade, sexo, raça, estilo de vida, dieta e infecção por retrovírus. Um total de 108 gatos foi incluído no estudo e 54 amostras de fezes foram obtidas desses animais. Somente 5,6% dos gatos foram sororreagentes para T. gondii, utilizando-se o teste de hemaglutinação indireta. Nenhum dos 54 gatos apresentou oocistos em suas amostras fecais. Embora sem comprovação estatística, machos, sem raça definida, com acesso livre às ruas e gatos com mais de dois anos de idade tenderam a ser mais expostos ao parasito. Idade, estilo de vida e uso de caixa de areia foram considerados importantes fatores de risco. Anemia e infecção por retrovírus não apresentaram relação com infecção por T. gondii. Não foram detectados anticorpos na maioria dos gatos (94,4%), indicando que esses gatos nunca foram expostos ao parasito e que, se infectados, poderão eliminar grande número de oocistos no ambiente

Condições sanitárias de uma colônia urbana de gatos (Felis catus Linnaeus, 1758) em um jardim zoológico do Rio de Janeiro, Brasil

The colony of urban stray cats living in the Rio de Janeiro zoological garden was studied in order to develop a population and health control program. As many cats as possible were captured during two months (47 animals) and were classified according to gender, age, weight and coat markings. They were submitted to a general health evaluation, examined for the presence of ectoparasites and sent to a surgical neutering program. All animals had a blood sample drawn for CBC, platelet count, heartworm and retroviruses detection. Capillary blood smears were made for hemoparasites detection. Coat marking and colors were tabby (59.7%), followed by solid black (17%); torbie (10.6%); bicolor (10.6%) and harlequin (2.1%). The only ectoparasites found were fleas, which infested 28% of the animals. The hemoparasites found were Haemobartonella felis (38%) and piroplasmas that could not be differentiated between Cytauxzoon spp. and Babesia spp. (47%). No cat was found infected by Dirofilaria immitis or FeLV (Feline Leukemia Virus), although FIV (Feline Immunodeficiency Virus) antibodies could be detected (21%). There was no correlation between hemoparasites and FIV infections. The estimated total cat population (mark-recapture method) was 59; 68% female and 32% male, suggesting that a neutering program is in fact needed.As condições sanitárias e composição populacional de uma colônia de gatos urbanos, errantes, habitantes do zoológico do Rio de Janeiro foram estudadas, objetivando-se um programa de controle populacional e sanitário. Capturou-se o maior número de indivíduos possível durante dois meses (47 animais). Os animais capturados foram examinados quanto ao gênero, idade, peso, pelagem, inspeção geral e presença de ectoparasitas e eram encaminhados a um programa de esterilização cirúrgica. Cada animal teve uma amostra de sangue colhida para realização de hemograma completo, plaquetometria, pesquisa de hemoparasitas e de retrovírus. As marcações e cores de pelagem encontradas foram "tabby" (70%), preta (17%); bicolor (11%) e arlequim (2%). A presença de pulgas foi observada em 28% dos animais. Os hemoparasitas encontrados foram Haemobartonella felis (38%) e piroplasmas indistinguíveis entre Cytauxzoon spp. e Babesia spp. (47%). Nenhum dos gatos foi encontrado com antigenemia de Dirofilaria immitis ou do vírus da leucemia felina (FeLV), embora anticorpos contra o vírus da imunodeficiência felina (FIV) tenham sido detectados (21%). Não houve correlação entre infecção por FIV e hemoparasitas. A população total estimada (método de captura-recaptura) foi de 59 gatos, sendo 68% fêmeas e 32% machos. Os resultados sugerem que um programa de esterilização cirúrgica é de fato necessário

Updated canine infection rates for Dirofilaria immitis in areas of Brazil previously identified as having a high incidence of heartworm-infected dogs

Background\ud Canine heartworm infections were frequently diagnosed in Brazil before the new millennium. After the year 2000, the frequency of diagnosis showed a sharp decline; however, a few years later, new evidence indicated that the parasite was still present and that canine infection rates seemed to be increasing. Therefore, an updated survey of canine heartworm prevalence was conducted in several locations in south, southeast, and northeast Brazil.\ud \ud \ud Methods\ud Dogs from 15 locations having previously reported a high prevalence of heartworm infection were included in the survey according to defined criteria, including the absence of treatment with a macrocyclic lactone for at least 1 year. Blood samples from 1531 dogs were evaluated by an in-clinic immunochromatography test kit (Witness® Heartworm, Zoetis, USA) for detection of Dirofilaria immitis antigen. At each location, epidemiologic data, including physical characteristics and clinical signs reported by owners or observed by veterinarians, were recorded on prepared forms for tabulation of results by location, clinical signs, and physical characteristics.\ud \ud \ud Results\ud The overall prevalence of canine heartworm infection was 23.1%, with evidence of heartworm-infected dogs detected in all 15 locations studied. There was a tendency for higher prevalence rates in environmentally protected areas, despite some locations having less-than-ideal environmental temperatures for survival of vector mosquitoes. Among physical characteristics, it was noted that dogs with predominantly white hair coats and residing in areas with a high (≥20%) prevalence of heartworm were less likely to have heartworm infection detected by a commercial heartworm antigen test kit than were dogs with other coat colors. In general, dogs older than 2 years were more frequently positive for D. immitis antigen than were younger dogs. Clinical signs of heartworm infections were rare or owners were unable to detect them, and could not be used for reliable prediction of the presence of heartworm.\ud \ud \ud Conclusions\ud These results indicate that the prevalence of D. immitis has increased in these areas of Brazil over the past few years. Small animal practitioners in these areas should include routine screening tests for heartworm infections in every dog’s annual evaluation protocol and make sure to have uninfected dogs on prevention.Zoeti

Genetics of randomly bred cats support the cradle of cat domestication being in the Near East

Cat domestication likely initiated as a symbiotic relationship between wildcats (Felis silvestris subspecies) and the peoples of developing agrarian societies in the Fertile Crescent. As humans transitioned from hunter-gatherers to farmers ~12,000 years ago, bold wildcats likely capitalized on increased prey density (i.e., rodents). Humans benefited from the cats’ predation on these vermin. To refine the site(s) of cat domestication, over 1000 random-bred cats of primarily Eurasian descent were genotyped for single-nucleotide variants and short tandem repeats. The overall cat population structure suggested a single worldwide population with significant isolation by the distance of peripheral subpopulations. The cat population heterozygosity decreased as genetic distance from the proposed cat progenitor’s (F.s. lybica) natural habitat increased. Domestic cat origins are focused in the eastern Mediterranean Basin, spreading to nearby islands, and southernly via the Levantine coast into the Nile Valley. Cat population diversity supports the migration patterns of humans and other symbiotic species

Análise da eficácia da Tirzepatida como agente terapêutico para perda de peso em pacientes com Obesidade

A obesidade e o diabetes são doenças crônicas que afetam milhões de pessoas em todo o mundo, sendo consideradas epidemias crescentes. O tratamento da obesidade envolve uma abordagem multifacetada, incluindo mudanças no estilo de vida e intervenções farmacológicas. Nesse contexto, a tirzepatida, uma terapia combinada de dois medicamentos que atuam em diferentes vias metabólicas para reduzir o apetite e promover a perda de peso em pacientes com obesidade, tem se destacado como uma opção terapêutica promissora. O objetivo deste estudo foi avaliar a eficácia e segurança da tirzepatida como agente terapêutico para perda de peso em pacientes com obesidade. Para isso, foram selecionados quatro artigos que avaliaram o uso da tirzepatida em pacientes com obesidade, publicados entre 2018 e 2023, nas bases de dados PubMed (Medline), Scientific Electronic Library Online (SciELO) e Cochrane Library. Os resultados indicam que a tirzepatida é uma terapia promissora e segura para perda de peso em pacientes com obesidade. Todos os estudos relataram perda de peso significativa em pacientes tratados com essa terapia, variando de 8,6% a 16,0% do peso corporal inicial. Além disso, a tirzepatida também apresentou efeitos benéficos em outros parâmetros metabólicos, como redução da glicemia e melhora da função hepática. Efeitos adversos foram relatados em menor frequência e gravidade em comparação com outras terapias para perda de peso. Em resumo, a tirzepatida é uma terapia combinada de dois medicamentos que tem demonstrado eficácia e segurança para a perda de peso em pacientes com obesidade, de acordo com os resultados de quatro estudos avaliados nesta pesquisa. Essa terapia pode ser uma opção terapêutica válida para pacientes com obesidade. No entanto, é importante destacar a necessidade de mais pesquisas para avaliar sua eficácia e segurança a longo prazo e sua aplicabilidade em diferentes populações. Portanto, é fundamental que o tratamento seja realizado com acompanhamento médico e que cada caso seja avaliado individualmente

What is known about Tritrichomonas foetus infection in cats?

Abstract Tritrichomonas foetus is a parasite that has been definitively identified as an agent of trichomonosis, a disease characterized by chronic diarrhea. T. foetus colonizes portions of the feline large intestine, and manifests as chronic and recurrent diarrhea with mucus and fresh blood, which is often unresponsive to common drugs. Diagnosis of a trichomonad infection is made by either the demonstration of the trophozoite on a direct fecal smear, fecal culture and subsequent microscopic examination of the parasite, or extraction of DNA in feces and amplification by the use of molecular tools. T. foetus is commonly misidentified as other flagellate protozoa such as Giardia duodenalis and Pentatrichomonas hominis. Without proper treatment, the diarrhea may resolve spontaneously in months to years, but cats can remain carriers of the parasite. This paper intends to serve as a source of information for investigators and veterinarians, reviewing the most important aspects of feline trichomonosis, such as trichomonad history, biology, clinical manifestations, pathogenesis, world distribution, risk factors, diagnosis, and treatment

Heat pretreatment of canine samples to evaluate efficacy of imidacloprid + moxidectin and doxycycline in heartworm treatment

Abstract Background Considering the recent information on the increase of Dirofilaria immitis antigen detection by rapid assays in canine blood samples after heat treatment, the proposal that immune complexes block D. immitis antigen detection and that macrocyclic lactone + doxycycline (alternative protocol) might lead to increased production of those immune complexes, resulting in the erroneous diagnosis of adult worm elimination, and that there is no recommended adulticide marketed in Brazil, a study was performed to evaluate the interference of moxidectin + doxycycline (moxi-doxy) on diagnostic procedures when heartworm positive dogs are treated with this alternative protocol. Twenty-two naturally infected pet dogs were treated monthly with topical 10% imidacloprid + 2.5% moxidectin and with oral doxycycline (10 mg/kg BID/30 days) (moxi-doxy). All the dogs had their microfilaremia level determined prior to the first day of treatment, and were tested every 6 months for microfilariae (Mf) detection prior to heating, and for antigen detection prior to and after heating, the sample. Results The results indicate that the treatment protocol can eliminate adult heartworms as early as 6 months after the first dose, especially in low microfilaremic dogs (< 300 Mf/ml). In this study, all dogs were free of heartworm antigen after 18–24 months of treatment. In a comparison of pre-heated samples and non-heated samples, sample pre-heating increased antigen detection sensitivity, and non-heated samples tended to be antigen-negative earlier than the pre-heated samples, especially when dogs had low microfilaremia levels. These discrepancies were not present in a subsequent sample of the same dog 6 months later. Conclusions Two negative antigen test results 6 months apart can be recommended as the criterion to consider when a dog has been cleared of infection. The initial microfilaremia level of a dog can be used to estimate the necessary time frame to end the treatment period

infection in two domestic cats with chronic diarrhea

Case series summary Chronic diarrhea is a common and recurring problem in feline medicine. Intestinal trichomonads have been reported as causative agents of diarrhea in cats. While Pentatrichomonas hominis is considered commensal, Tritrichomonas foetus has been found to cause feline large bowel diarrhea in cats. In our report, two young cats infected with the feline leukemia virus (FeLV) and presenting with chronic diarrhea were identified as having trichomonads in their feces, based on direct examination and fecal culture. Molecular assays (PCR and DNA sequencing) revealed that the parasite involved was P hominis , not T foetus , as was suspected. The animals had already been subjected to ineffective therapy with metronidazole, and after the use of ronidazole, their feces became dry and formed. Relevance and novel information This case report describes P hominis infection as a possible cause of chronic diarrhea in two young cats also infected by FeLV. The parasite was probably resistant to metronidazole, the drug of choice in the literature, and sensitive to ronidazole. Although considered commensal, P hominis infection should be evaluated as a differential diagnosis in cats with chronic diarrhea, especially those that are immunocompromised. Moreover, a combination of techniques such as direct examination and/or fecal culture and PCR is essential for an accurate diagnosis of P hominis infection

Serological evidence of canine arthropod-borne infections in an ecotone area of a natural reserve at the Pantanal, Brazil

Arthropod-borne infections are dependent on environmental conditions; therefore, anthropomorphic meddling may disrupt the natural balance that maintains wildlife. It is common to find dogs roaming in Brazilian natural reserves, what favors the spillover of pathogens among species. The aim of this study was to determine the canine seroprevalence of Ehrlichia canis, E. ewingii, Anaplasma platys, A. phagocytophilum, Borrelia burgdorferi, Leishmania infantum and Dirofilaria immitis using 84 serum samples from dogs from the border area of the SESC-Pantanal reserve (RPPN SESC-Pantanal 16°40 ́51 ́ ́S;56o17 ́45 ́ ́W) stored at the Laboratório de Protozoologia e Imunomodulação, Instituto Oswaldo Cruz. Samples were tested with SNAP Canine Leishmania Antibody Test (IDEXX Laboratories) or DPP canine visceral leishmaniasis test (Bio-Manguinhos) for the presence of L. infantum antibodies and with SNAP 4Dx Plus Test (IDEXX Laboratories) for D. immitis, Ehrlichia spp., Anaplasma spp. and B. burgdorferi seroprevalences. The seroprevalence for tick-borne parasites was 79.8%, 13.1% for L. infantum and 7.1% for D. immitis. Since tick-borne parasites were the most frequent among the examined dogs it may be suggested that these parasites, ticks and hosts display special resilience skills to overcome the hostile local conditions. The low L. infantum prevalence suggests that the local biodiversity, especially the bird abundance, depurates Leishmania circulation. The mosquito-borne D. immitis prevalence was higher than expected, suggesting that the local flooding regime provides suitable mosquito-breeding spots. On the other hand, the only known vector in the area feeds on birds, therefore reducing mosquitoes worm burden and imparing D. immitis transmission