Comparative efficacy of buparvaquone and imidocarb in inhibiting the in vitro growth of Babesia bovis.

Introduction: B. bovis is an apicomplexan parasite responsible for bovine babesiosis, a tick-borne disease with a worldwide impact. The disease remains inefficiently controlled, and few effective drugs, including imidocarb dipropionate (ID), are currently available in endemic areas. The objective of this study was to evaluate whether buparvaquone (BPQ), a drug currently used to treat cattle infected with the Babesia-related Theileria spp. parasites, could be active against Babesia parasites. Herein, we compared the effect of ID and BPQ on B. bovis growth in vitro erythrocyte culture. Methods: We compared the effect of ID and BPQ on the culture-adapted Texas T2Bo strain of B. bovis. In vitro cultured parasites were incubated with ID and BPQ at two starting parasitemia levels (PPE), 0.2% and 1%. In vitro cultured parasites were treated with ID or BPQ at concentrations ranging from 10 to 300 nM, during 4 consecutive days. Parasitemia levels were daily evaluated using microscopic examination. Data was compared using the independent Student's t-test. Results and discussion: Both ID and BPQ significantly inhibited (p < 0.05) the growth of B. bovis, regardless of the initial parasitemia used. At 1% parasitemia, BPQ had lower calculated inhibitory concentration 50 (IC50: 50.01) values than ID (IC50: 117.3). No parasites were found in wells with 0.2% starting parasitemia, treated previously with 50 nM of BPQ or ID, after 2 days of culture without drugs. At 1% parasitemia, no parasite survival was detected at 150 nM of BPQ or 300 nM of ID, suggesting that both drugs acted as babesiacidals. Conclusion: Overall, the data suggests that BPQ is effective against B. bovis and shows a residual effect that seems superior to ID, which is currently the first-line drug for treating bovine babesiosis globally.

First report of an outbreak of "Q" fever IN an abattoir from Argentina.

In late October 2021, one of the veterinarians and the occupational physician of a bovine and swine abattoir from Entre Ríos Province, Argentina were alerted about workers with atypical pneumonia symptoms, raising suspicious of a possible Q fever outbreak. An outbreak epidemiological investigation was carried out. Analysis was based on the description of the study population, according to gender, age, symptoms, and position within the abattoir, as well as on outbreak epidemic curve and its probable origin. Cases of Q fever in the workers were confirmed by serology. Measurements of the association between the evaluated variables and the risk of exposure were investigated and calculated as attack rates. The outbreak occurred between October and November 2021, symptomatically affecting 11 workers, out of a total exposed population of 49 individuals. The index case was a 33-year-old male who started with symptoms on 27 October 2021, and the outbreak extended for at least 17 days. Workers in the clean zone of the slaughter floor had a 4.68 times higher risk of contracting Q fever than people located in other areas. Importantly, two pregnant cows were slaughtered a few days before the outbreak began, which could have been the origin of the outbreak. The present study demonstrates the urgent need to consider Q fever when diagnosing abortive diseases of ruminants in Argentina, as well as in zoonotic disease epidemiological surveillance to inform all actors of the health system.

Human toxocariasis seroprevalence among patients with uveitis in Alborz Province, Iran.

INTRODUCTION AND OBJECTIVE: Toxocariasis, predominantly caused by Toxocara canis, is a common zoonotic parasitosis worldwide. Toxocara infection is a cause of vision impairment and blindness. The presented study investigates the frequency of antibodies against Toxocara among uveitis patients and the epidemiological factors associated with disease. MATERIAL AND METHODS: Fifty-four patients with uveitis and 59 healthy subjects were studied. Anti-Toxocara antibodies status was determined in all serum samples using enzyme linked immunosorbent assay (ELISA), and seropositive samples analyzed by Western blot (WB) technique. RESULTS: The frequency of Toxocara canis infection was found to be significantly higher in uveitis patients, compared to healthy controls by the use of ELISA test, being 14.8% and 1.7%, respectively. From 8 seropositive samples, 5 (62.5%) patients exhibited Toxocara immunoglobulin G (IgG) antibodies in response to Western blot, whereas in the control group, none were detected positive by Western blot. No significant difference was found between pet owners, nor between different places of residence. The seroprevalence to Toxocara among uveitis patients was significantly related to gender, age and medical diagnosis. The highest prevalence was found in patients with posterior uveitis (27.8%). CONCLUSIONS: Anti-Toxocara antibody titers are associated with the risk of vision impairment -uveitis. The risk factor associated with Toxocara exposure identified in this study warrants further investigation.

Larval development of Aelurostrongylus abstrusus in experimentally infected Rumina decollata snails.

Aelurostrongylus abstrusus is a lungworm distributed worldwide that affects wild and domestic cats, causing bronchopneumonia of varying intensity. Snails serve as intermediate hosts. The aim of the present study was to assess the larval development of A. abstrusus in R. decollata snails and to investigate its potential as an intermediate host. For this purpose, first-stage larvae (L1) of A. abstrusus were obtained from the faeces of naturally infected cats. Doses of 500 L1/snail were given to 24 R. decollata snails, placed on the soil of the breeder chamber, and maintained under laboratory conditions. Three snails were killed at 8, 10, 12, 16, 22, 26, 45 and 55 days post-infection (dpi), and the muscular foot and visceral body were separately digested by an artificial digestion technique. The morphometric parameters of different larval stages were recorded. The mean number of larvae reaching the infective stage at the end of the study (L3) was 262 larvae/snail. The greatest development to L3 was recorded from days16 to 55 pi, during which the isolation was maximum. A. Abstrusus L3 were isolated from the viscera, but isolation from the snail foot was significantly higher. Our results showed for the first time the ability of A. Abstrusus larvae to develop in R. decollata, thus serving as a potential intermediate host.

Epidemiología de parásitos zoonóticos en barrios vulnerables / Epidemiology of zoonotic parasites in vulnerable neighborhoods

El suelo es una importante vía de trasmisión de numerosos patógenos humanos, dentro de los cuales se encuentra un grupo de enfermedades parasitarias helmínticas conocidas como Geohelmintiasis (Soil Transmited Helminths). Strongyloides stercoralis, Toxocara spp. y Ancylostoma spp. conforman el grupo de las geohelmintiasis zoonóticas, helmintiasis de los animales de compañía con capacidad de infectar al hombre (Alvares et al., 2011). Los protozoarios entéricos Giardia intestinalis y Cryptosporidium spp. son parásitos cosmopolitas de importancia en salud pública por ser la principal causa de diarrea no viral transmitidas por el agua que afecta a millones de personas en todo el mundo (Savioli et al. 2006). Los animales de compañía actúan como reservorios y potenciales transmisores de geohelmintiasis y protozoarios zoonóticos al ser humano debido a la convivencia y al contacto estrecho. Dadas las condiciones epidemiológicas de los ciclos parasitarios, exposición y transmisibilidad, la población humana en riesgo la constituyen, sobre todo, los niños (entre los 6 meses y 4 años de edad) y en etapa escolar (5 a 14 años), residentes en países tropicales y subtropicales, dentro de los cuales forma parte una extensa área del territorio Argentino (Chiodo et al. 2006; Alvares Santarém et al. 2011). Ello debido a que los hábitos de higiene son escasos en esta franja etaria, al contacto estrecho con el suelo y las mascotas, y a comportamientos de pica y/o geofagia, muchas veces inducidos por la desnutrición infantil (Despommier 2003; Rubinsky-Elefant et al. 2010). El presente proyecto fue diseñado en base a un estudio epidemiológico descriptivo de prevalencia de parasitosis en caninos y felinos en el Barrio Los Piletones de Villa Soldati, CABA, durante un año de seguimiento. Se estudiaron las prevalencias de las parasitosis generales y específicas, así como las asociaciones parasitarias más prevalentes, correlacionando la información con datos de encuestas previas sobre tenencia responsable, hábitos y características epidemiológicas de la población del Barrio. Además, se realizó la tipificación molecular de Giardia spp. para la detección de ensamblajes zoonóticos y específicos de caninos y felinos (A, B, D, y F)

Primer reporte de Toxocara cati en el caracol doméstico Rumina decollata / First report of Toxocara cati in the domestic land snail Rumina decollata

Se estudió el rol prospectivo de Rumina decollata como potencial hospedador paraténico de Toxocara cati para los gatos domésticos. Se recolectaron caracoles R. decollata y heces de gatos de un hospital de la Ciudad Autónoma de Buenos Aires. Se procesaron las heces y los caracoles fueron digeridos para identificar estadios de T. cati por análisis morfológico y molecular. El 23,5% (4/17) de las muestras de heces resultaron positivas a huevos larvados de T. cati. El 20% (5/25) de los pooles de caracoles fue positivo a larvas de tercer estadío (L3) de Toxocara spp. por PCR. El promedio de larvas totales recuperadas por gramo de caracol en todos los pooles positivos fue de 5.1, con un máximo de 33 L3/pool. Se trata del primer reporte de R. decollata como hospedador paraténico de T. cati, puesto que ha sido demostrada la infección en caracoles y gatos en un ambiente común

The prospective role of the land snail Rumina decollata as a potential paratenic host of Toxocara cati for domestic cats was studied. R. decollata specimens and cats' feces were collected from the open spaces of a Buenos Aires city hospital. Cats' feces were analyzed and snails were digested to identify T. cati stages, by morphological and molecular analyses. T. cati larval eggs were recovered from 23.5% (4/17) of the sampled feces. Twenty percent of snail pools (5/25) were confirmed to be positive for Toxocara spp. third larval stage (L3) by PCR. The mean value of total larvae recovered per gram of snail in all positive pools was 5.1, with a maximum 33 L3/pool. This is the first report of T. cati infective larvae in R. decollata domestic snail as a paratenic host, since the relationship between infection in snails and in cats' feces could be demonstrated in a common environment

First report of Toxocara cati in the domestic land snail Rumina decollata.

The prospective role of the land snail Rumina decollata as a potential paratenic host of Toxocara cati for domestic cats was studied. R. decollata specimens and cats' feces were collected from the open spaces of a Buenos Aires city hospital. Cats' feces were analyzed and snails were digested to identify T. cati stages, by morphological and molecular analyses. T. cati larval eggs were recovered from 23.5% (4/17) of the sampled feces. Twenty percent of snail pools (5/25) were confirmed to be positive for Toxocara spp. third larval stage (L3) by PCR. The mean value of total larvae recovered per gram of snail in all positive pools was 5.1, with a maximum 33 L3/pool. This is the first report of T. cati infective larvae in R. decollata domestic snail as a paratenic host, since the relationship between infection in snails and in cats' feces could be demonstrated in a common environment.

[Assessment of transmammary transmission of Trichinella patagoniensis in BALB/c mice]. / Evaluación de la transmisión galactógena de Trichinella patagoniensis en ratones BALB/c.

Since 1916 to date, it has been suspected that vertical transmission of parasites from the genus Trichinella could occur in pregnant or lactating women during the parenteral phase of infection. The aim of the present study was to evaluate the transmammary transmission of T. patagoniensis in BALB/c mice. Twenty 7-week-old BALB/c mice were distributed into two groups of 10 individuals each, depending on the time of gestation when they were infected, 15 or 18 days after detection of the vaginal plug. Each group was subdivided into two subgroups of 5 mice each, which were given an oral dose of 100 or 500 infective larvae respectively. Euthanasia and subsequent artificial digestion was performed in the pups and the dams. No T. patagoniensis L1 larvae were found in any of the offsprings analyzed. The observed results suggest that vertical transmission of T. patagoniensis would not be possible in BALB/c mice.

Experimental infection with Toxocara cati in pigs: migratory pattern and pathological response in early phase.

Experimental inoculations of approximately 100,000 infective Toxocara cati larval eggs were done in twelve pigs. The T. cati eggs used for inoculation were collected from cat's feces. Another group of three pigs served as an uninfected control. Groups of infected pigs were euthanized at seven, 14, 21, and 28 days post-inoculation (dpi). Tissue samples were taken for digestion and histopathology changes in early phase. The number of larvae recovered from the lungs peaked at seven and 14 dpi and were also present at 21, and 28 dpi. Larvae of T. cati were present in the lymph nodes of the small and large intestine at seven, 14, and 28 dpi and at seven, 14, 21, and 28 dpi respectively. In other studied tissues, no larvae or less than one larva per gram was detected. The pathological response observed in the liver and lungs at seven and 14 dpi, showed white spots on the liver surface and areas of consolidation were observed in the lungs. The lungs showed an inflammatory reaction with larvae in center at 28 dpi. In the liver we observed periportal and perilobular hepatitis. The lymph nodes of the intestines displayed eosinophil lymphadenitis with reactive centers containing parasitic forms in some of them. The granulomatous reaction was not observed in any tissues. The role of the other examined tissues had less significance. The relevance of this parasite as an etiological agent that leads to disease in paratenic hosts is evident.

EXPERIMENTAL INFECTION WITH Toxocara cati IN PIGS: MIGRATORY PATTERN AND PATHOLOGICAL RESPONSE IN EARLY PHASE / Infección experimental en cerdos con Toxocara cati: patrón migratorio y respuesta patológica en etapa temprana

Experimental inoculations of approximately 100,000 infective Toxocara cati larval eggs were done in twelve pigs. The T. cati eggs used for inoculation were collected from cat's feces. Another group of three pigs served as an uninfected control. Groups of infected pigs were euthanized at seven, 14, 21, and 28 days post-inoculation (dpi). Tissue samples were taken for digestion and histopathology changes in early phase. The number of larvae recovered from the lungs peaked at seven and 14 dpi and were also present at 21, and 28 dpi. Larvae of T. cati were present in the lymph nodes of the small and large intestine at seven, 14, and 28 dpi and at seven, 14, 21, and 28 dpi respectively. In other studied tissues, no larvae or less than one larva per gram was detected. The pathological response observed in the liver and lungs at seven and 14 dpi, showed white spots on the liver surface and areas of consolidation were observed in the lungs. The lungs showed an inflammatory reaction with larvae in center at 28 dpi. In the liver we observed periportal and perilobular hepatitis. The lymph nodes of the intestines displayed eosinophil lymphadenitis with reactive centers containing parasitic forms in some of them. The granulomatous reaction was not observed in any tissues. The role of the other examined tissues had less significance. The relevance of this parasite as an etiological agent that leads to disease in paratenic hosts is evident.

Se realizó la infección experimental de doce cerdos con aproximadamente 100.000 huevos infectivos de Toxocara cati. Los huevos de T. cati utilizados en la inoculación fueron recolectados de heces felinas. Otro grupo de tres cerdos no infectados se utilizó como control. Grupos de cerdos infectados se eutanaciaron a los 7,14,21 y 28 días posinoculación (pi). Se tomaron muestras de tejidos para digestión y evaluación de cambios histopatológicos en la etapa temprana de la infección. El número de larvas recuperadas de los pulmones se incrementó en los días 7 y 14 pi, recuperándose también los días 21 y 28 pi. Se encontraron larvas de T. cati en los linfonódulos del intestino delgado y grueso los días 7,14 y 28 pi y los días 7,14,21 y 28 pi respectivamente. En los restantes tejidos estudiados o no se recuperaron larvas o los valores fueron menores a una larva por gramo de tejido. La respuesta patológica observada en el hígado y los pulmones a los 7 y 14 días posinoculación, mostró en la superficie del hígado manchas blancas y en los pulmones áreas de consolidación. Los pulmones presentaron una reacción inflamatoria con presencia de larva en el centro en el día 28 pi. En el hígado se observó una hepatitis periportal y perilobular. Los linfonódulos del intestino presentaron una linfoadenitis eosinofílica con un centro reactivo conteniendo formas parasitarias en algunos de ello. En ninguno de los tejidos se observó la típica reacción granulomatosa. El rol de los restantes tejidos examinados fue de menor significancia. Queda evidenciada la importancia de éste parasito como un agente etiológico que desarrolla la enfermedad en hospederos paraténicos.

Trichinella infection in wild animals from endemic regions of Argentina.

Natural infection with Trichinella has been described in more than 150 mammalian species. However, few reports of Trichinella infection in wild animals have come from Argentina. In this study, muscle tissue was obtained from wild animals in Argentina with the aim of evaluating the presence of Trichinella. A total of 169 muscle samples were collected to determine the presence of Trichinella larvae by artificial digestion. The 169 muscle samples originated from 12 species including 36 opossums (Didelphis albiventris), 19 armadillos (Chaetophractus villosus), 9 capybaras (Hydrocaeris hydrocaeris), 1 puma (Puma concolor), 3 grey fox (Lycalopex gymnocercus), 6 coypus (Myocastor coypus), 6 skunks (Conepatus chinga), 2 ferrets (Galictis cuja), 66 rats (Rattus norvegicus), 6 mice (Mus musculus), 12 wild boars (Sus scrofa), and 3 wild cats (Felis geoffroyi). Trichinella infection was detected in 1 puma [2 larvae per gram (LPG)], 3 wild boars (8-420 LPG), 3 armadillos (0.04-0.08 LPG), and 9 rats (0.1 to 150 LPG). Only 3 Trichinella isolates, of 1 rat and 2 wild boars from Neuquén, were identified as Trichinella spiralis by nested PCR. The presence of Trichinella infection among wild animal populations suggests a sylvatic cycle of transmission in Argentina, which can serve as a reservoir for humans and domestic animals. Further, evidence of high prevalence in rats emphasizes the need to improve pig management, mainly in small individual farms without adequate technology, to enhance the quality of feeds, and to improve veterinary services to avoid exposure of pigs to Trichinella.

Estudio preliminar sobre los distintos estadios de Toxocara cati en gatos / Preliminary study on the different stages of Toxocara cati in cats

Las larvas de T. cati tienen la capacidad de realizar migraciones por los tejidos del gato, permaneciendo infectivas. El objetivo del presente estudio fue determinar la presencia de distintos estadios de T. cati en gatos naturalmente infectados. Se efectuó la necropsia de 12 gatos hallados muertos en la vía pública. Se tomaron muestras de materia fecal para análisis coproparasitológico y muestras de músculo, la totalidad de los pulmones, rí±ones, hígado y cerebro. Se utilizó la técnica de digestión artificial rßpida para detectar la presencia de larvas de Toxocara cati en los tejidos. El análisis coproparasitológico fue positivo a T. cati en un 25 por ciento, a Toxascaris leonina en un 16, 66 por ciento y en un 8,33 por ciento a ambas especies. El 50 por ciento de los animales presentó parásitos adultos de T. cati, de los cuales el 20 por ciento presentó parasitosis mixta con T. leonina. La existencia de parásitos adultos y su relación con la edad del animal fue estadísticamente significativa. No resultó estadísticamente significativa con respecto al sexo. En el análisis de las muestras de órganos y tejidos no se detectaron larvas de T. cati. Las diferencias obtenidas en los resultados con la técnica coproparasitológica y con la necropsia podrían deberse a la presencia de estadios inmaduros o a la eliminación intermitente de huevos por materia fecal. La ausencia de larvas en los tejidos plantea diversos interrogantes que podrían condicionar el comportamiento migratorio de las mismas en el gato. Es necesario incrementar la cantidad de felinos estudiados y realizar estudios bajo condiciones controladas de infección para obtener un mayor conocimiento sobre el comportamiento de las larvas de T. cati durante la fase migratoria en el gato.

Toxocara cati larvae are able to migrate through the tissues of the cat, remaining infective. The objective of this study was to determine the presence of different stages ofT. cati in naturally infected cats. Twelve cats found dead in the street were necropsied and samples of faeces were collected for coproparasitological analysis. Samples of muscle, the lungs, kidneys, liver, mammary gland and brain were removed. They were processed by the rapid artificial digestion technique to detect T. cati larvae. Coproparasitological analysis was positive for T. cati by 25 percent, to Toxascaris leonina at 16, 66 percent and 8.33 percent to both species. The 50 percent of animals presented adult parasites ofT. cati, of which 20 percent were positive to T. leonina. Statistically significant differences were found between the presence of adult parasites and cat's age. No statistically significant differences were observed in regard to sex. No larvae ofT. cati were recovered from tissues. The differences in the results obtained between the coproparasitological technique and the necropsy could be due to the presence of immature stages of the parasites or to intermittent elimination of eggs in faeces. The absence of larvae in tissues raises several questions related to the migratory behaviour of T. cati larvae. Increasing the number of felines studied will contribute to ensure the validity of the results and will provide a better understanding about the behavior ofT. cati larvae during the migratory phase in the cat.