Vigilancia molecular de la malaria en potenciales reservorios silvestres que viven en una región históricamente endémica de Paraguay / Molecular surveillance of malaria in potential wild reservoirs that live in a historically endemic region of Paraguay

En Paraguay, no se han registrado casos autóctonos de malaria desde el 2011. Se realizó un estudio descriptivo observacional transversal en 6 monos y 23 aves que vivían en una región históricamente endémica de Paraguay para buscar presencia de reservorios silvestres de parásitos plasmodios causantes de la malaria. El ADN se extrajo por el método de Chelex a partir de una gota de sangre en un papel de filtro, y la detección del parásito se realizó mediante la PCR múltiple semianidada. Por este método, no se detectaron parásitos en ninguna de las 29 muestras. Se evaluó el riesgo potencial de circulación selvática de los parásitos que causan la malaria. Teniendo en cuenta la presencia de mosquitos anofelinos vectores en la zona, el hecho de que no se hayan observado casos positivos es un buen indicador teniendo en cuenta que nuestro país fue declarado recientemente como país libre de malaria por la OMS(AU)

In Paraguay, autochthonous cases of malaria have not been recorded since 2011. A cross-sectional observational descriptive study was conducted in 6 monkeys and 23 birds living in a historically endemic region of Paraguay to identify wild reservoirs of plasmodium parasites that cause malaria. DNA was extracted by the Chelex method from a blood drop in a filter paper, and parasite detection was performed by the seminested multiplex PCR. By this method, parasites were not detected in any of the 29 samples. The risk of potential sylvatic circulation of the parasites causing malaria was evaluated. Considering the presence of anopheline mosquitoes in the area, the fact that we did not find any positive cases is a good indicator as our country was recently certified as a malaria-free country by the WHO(AU)

Comparative study of three xenic media culture for cultivation of Balantidium coli strains / Estudo comparativo entre três meios de cultivo xênicos para o cultivo de cepas de Balantidium coli

Abstract The aim of the present study was to evaluate the growth rate of Balantidium coli in three xenic media cultures. Between 2013 and 2015, 10 B. coli isolates obtained from feces of Cynomolgus macaques, and 30 isolates from feces of pigs were studied. An inoculum of 500 trophozoites was transferred to tubes containing LES, TYSGM-9 and Pavlova media. These cultures were evaluated at incubation times of 24, 48, 72 and 96 hours. In most of strains analyzed wasn't showed significant difference in the growth rate comparing TYSGM-9 and Pavlova media (Wilcoxon p>0.016). In Pavlova medium, the trophozoites showed a maximum growth at 72 hours with significant difference when compared with the times of 24 h and 96 h (Wilcoxon <0.008). In LES, viable trophozoites were observed until 24 hours, with a significant difference (Friedman p<0.05, Wilcoxon p<0.016) in the number of parasite cells compared with Pavlova and TYSGM-9 media cultures. Thus, LES medium seemed to be less adequate than the other media for maintenance of B. coli. Despite the satisfactory results in TYSGM-9, Pavlova medium was considered ideal for the maintenance of this protozoan strain, guaranteeing the viability of the parasite with subculture every three days, presenting lower costs.

Resumo O objetivo do presente estudo foi avaliar a taxa de crescimento de Balantidium coli em três meios de cultura xênicos. Entre 2013 e 2015 foram estudados 10 isolados de B. coli obtidos de Cynomolgus macaques e 30 isolados de suínos. Um inóculo contendo 500 trofozoítos foi transferido para tubos contendo os meios LES, TYSGM-9 e Pavlova. Os cultivos foram avaliados com tempos de incubação de 24, 48, 72 e 96 horas. Na maioria das cepas analisadas não foi observado diferença significativa na taxa de crescimento comparando TYSGM-9 e Pavlova (Wilcoxon p>0,016). Em Pavlova, os trofozoítos apresentaram máximo de crescimento a 72 h com diferença significativa quando se comparou com os tempos de 24 h e 96 h (Wilcoxon <0,008). Em LES observou-se trofozoítos viáveis até 24 horas com diferença significativa (Friedman p<0,05 e Wilcoxon p<0,016), na quantidade de células parasitárias, quando comparado com Pavlova e TYSGM-9. Dessa forma, o meio LES mostrou-se ser menos adequado do que os outros, para a manutenção de B. coli. Apesar do resultado satisfatório em TYSGM-9, Pavlova foi considerado ideal para manutenção do protozoário, por garantir a viabilidade do parasito com subcultivos a cada três dias, além de apresentar menor custo.

A Histologic Demonstration of Siliceous Materials in Simian Lung Mite Infected Lung Tissues by Microincineration

Approximately 90% of freshly imported macaques and other Old World Monkeys are known to be infected with respiratory mites. The lung associated pigments are integral components of pulmonary acariasis in Old World Monkeys; at least three distinctive pigmental bodies are identified in association with lung mite infection. Two major components of pigments are recently identified as silica by using elemental analysis using a high voltage electron microscope and an energy-dispersive X-ray analysis technique. Since a limited number of infected monkey lung tissues and associated pigments can be examined by this tedious procedure, it was important for us to examine much greater number of specimens to verify our initial observation. Ten microincineration technique described provided a unique and practical way to identify the mineral elements in as many 27 histologic sections within a short span of time. Silica and silicates are heat resistant whereas majority of organic materials including lung mite parasites disintegrated under the extreme temperature. Mineral elements were exclusively located within the polarizable white ash. More than 90% of total pigmental bodies identified were found to be related to siliceous materials in 20 incinerated infected monkey lung tissues whereas five noninfected lungs similarly examined did not reveal any pigmental bodies. Other than a small of fine granular mucin substances which were PAS positive, the majority of lung mite associated pigments such as large granules of hemosiderin, needle-like crystals and other fine granules engulfed by macrophages were identified to be siliceous materials as they have persisted even after microincineration. Mite parasites and other organic materials were completely disintegrated. Similar pigmental bodies examined by microscope X-ray analysis were positive for silicate. This finding suggests that lung mite infection in Old Monkeys apparently predisposed silicosis. Therefore, until the link between lung mite infection and silicosis is clarified, expreimental inhalation toxicologic findings in mite-infected Old World monkeys should be interpreted cautiously.

Are asian monkeys the original mammalian hosts of Trypanosoma conorhini

Apresenta-se a hipótese de que os hospedeiros originais do Trypanosoma cororhini poderiam ser macacos asiáticos, porque a infecçäo natural destes tem sido achada, o vetor entre ratos é um Triatomíneo tropicopolita que pertence a um complexo de espécies asiáticas e os primatas têm-se mostrado mais suscetíveis ao parasito do que os ratos

Studies on trypanosomes in the Taiwan monkey.

Fifty-three or 9% of 594 Taiwan monkeys, Macaca cyclopis, were found infected with a Trypanosome species. The parasites were recovered from monkey blood in diaphasic blood-agar culture medium with a Locke's solution overlay. Trypanosomes were found on only a few thick blood smears and no dividing or multiplying forms were found. Some of the organisms had a free-flagellum (4.7 microns), an undulating membrane and both ends of the body were pointed. The total length averaged 41.7 microns; nucleus was slightly anteriorly located. Blood from culture positive monkey would not infect monkeys or other animals, but cultured parasites readily infected monkeys and one mouse, and one rat treated with cortisone. Triatoma rubrofasciata and Triatoma protracta fed upon culture-positive monkeys did not become infected but one of the former became infected after membrane feeding upon cultured parasites mixed with monkey blood. Studies were also done on the development of Trypanosome conorhini in monkeys and other animals. The parasite was recovered from the hind-and mid-gut of naturally infected Taiwan Triatoma rubrofasciata (109 of 117). Some bugs also had salivary gland infections. Most laboratory animals (rats, mice, Mongolian gerbils, guinea pigs, rabbits) developed infections detected by blood-smear and culture. The parasite was serially passaged through monkeys and bugs monthly for one year but there was no change in the development pattern. Only trypmastigotes were present in blood smears; no dividing forms were found. Triatoma rubrofasciata and Triatoma protracta readily developed gut infections when fed upon monkeys, but only a few Rhodnius prolixus became infected.(ABSTRACT TRUNCATED AT 250 WORDS)