Haemolytic activity of Actinobacillus actinomycetemcomitans strains on different blood types

Haemolytic activity of sixty nine Actinobacillus actinomycetemcomitans strains on different animal and human blood types was examined by using a trypticase soy agar supplemented with yeast extract (0.5%). Blood types used were: rabbit, sheep and human (A, Rh+; A, Rh-; B, Rh+; B, Rh-; O, Rh+; O, Rh-; AB, Rh+; AB, Rh- groups). Plates were inoculated and, incubated in microaerophilic conditions, at 37ºC, for 48 h. The haemolytic activity of the tested strains was characterized as alpha-haemolysis. Only two isolates were not haemolytic on all blood types (2.9%), two strains were haemolytic only on human blood (one strain on AB, Rh+ group and another one on A, Rh+ and AB, Rh+ groups). No specificity between haemolysin produced by the tested strains and blood type was observed.

Antigenic typing of brazilian rabies virus samples isolated from animals and humans, 1989-2000

Animal and human rabies samples isolated between 1989 and 2000 were typified by means of a monoclonal antibody panel against the viral nucleoprotein. The panel had been previously established to study the molecular epidemiology of rabies virus in the Americas. Samples were isolated in the Diagnostic Laboratory of the Pasteur Institute and in other rabies diagnostic centers in Brazil. In addition to the fixed virus samples CVS-31/96-IP, preserved in mouse brain, and PV-BHK/97, preserved in cell culture, a total of 330 rabies virus samples were isolated from dogs, cats, cattle, horses, bats, sheep, goat, swine, foxes, marmosets, coati and humans. Six antigenic variants that were compatible with the pre-established monoclonal antibodies panel were defined: numbers 2 (dog), 3 (Desmodus rotundus), 4 (Tadarida brasiliensis), 5 (vampire bat from Venezuela), 6 (Lasiurus cinereus) and Lab (reacted to all used antibodies). Six unknown profiles, not compatible with the panel, were also found. Samples isolated from insectivore bats showed the greatest variability and the most commonly isolated variant was variant-3 (Desmodus rotundus). These findings may be related to the existence of multiple independent transmission cycles, involving different bat species.

Melanoides tuberculatus (Gastropoda: Thiaridae) as intermediate host of Heterophyidae (Trematoda: Digenea) in Rio de Janeiro metropolitan area, Brazil

In the late 1960s, Melanoides tuberculatus snails were introduced in Brazil from North/East Africa and Southeast Asia. The first records of specimens infected with cercariae were registered in Rio de Janeiro State in 2001. The present study reports the occurrence of M. tuberculatus infected with larval trematodes in Rio de Janeiro City. Bottom sediment was collected with dip nets and sieved through 0.25 inch-mesh screening. Snails were transported to the laboratory in vials with stream water, then measured and individually isolated in glass vials with distilled water. They were exposed to artificial light and temperature to induce cercarial emergence. The most actively emerging cercariae were processed by differential staining and silver nitrate impregnation methods. Negative snails were subsequently dissected. Approximately 700 snails were collected. Snail total lengths ranged from 1.2 to 3.3 cm. The prevalence rate was 15.76% although 53.76% of the snails were found infected in one of the sites. Infected snails were infected with rediae and pleurolophocercous cercariae. Cercarial morphology and chaetotaxy were consistent with those of the family Heterophyidae mostly due to the presence of median dorsal and ventral fins on the tail and the absence of CI dorsal sensory receptors.

New data on Echinococcus spp. in Southern Brazil

40 Echinococcus isolates from sheep and cattle in Southern Brazil were genetically analysed in order to obtain further data on the presence of different taxa of the Echinococcus granulosus complex. Differentiation was done using a PCR technique and sequencing of mitochondrial cytochrome c oxidase subunit 1 (CO1). Most samples (38) could be allocated to the sheep strain (G1) of E. granulosus, while two samples belonged to E. ortleppi, previously known as cattle strain (G5) of E. granulosus. Due to the shorter prepatent period in dogs of the latter taxon, this records have important implications for the design of control measures in this endemic region.

Thermostability of heterophile antibodies from human sera infected with Schistosoma mansoni and geo-helminths: an immuno-metric statistical analysis

Antibody in human sera that induces lysis of sheep erythrocytes in hemolytic assay was investigated. The present study showed that the presence in serum of the thermostable cytolytic anti-sheep red blood cells antibodies is dependent on the Schistosoma mansoni infection, and this is more frequent in adults than in children. The thermostable characteristic of hemolysins in normal sera was not dependent on the presence of Ascaris lumbricoides, Trichuris trichiura or hookworm geo-helminths. Further, thermostable complement-activating heterophile antibodies were noticed in children in association with massive number of S. mansoni eggs. The results were obtained by using the z- and the chi-square tests. The z-test allows us to formulate a one-sided alternative, i.e., a tendency of one of the attributes. On the other hand, the chi-square test analyzes the independence between attributes by using a contingency table. Besides the obtained results being interesting in the field of schistosomiasis mansoni, they can provide a new insight into the use of statistics in medical science.

Cutaneous infection caused by Corynebacterium pseudodiphtheriticum: a microbiological report

We report here a rare case of cutaneous infection due to Corynebacterium pseudodiphtheriticum. The patient presented to the clinical laboratory with a skin ulcer on his left leg. Gram-stained preparation of the purulent secretion revealed the presence of numerous rod-shaped Gram-positive organisms in the absence of any other species. The organism was grown in pure culture on sheep blood agar and was further identified as C. pseudodiphtheriticum using a commercial identification system (API-Coryne, BioMérieux, France). The infection was successfully treated with ciprofloxacin. This case emphasizes the importance of the clinical microbiology laboratory in correctly identifying Gram-positive organisms obtained in pure culture from skin ulcers.

Cystic echinococcosis in southern Brazil

Cystic echinococcosis (CE) is very common in the southern part of Rio Grande do Sul State where sheep and cattle raising is the most important economical activity. Prevalence in intermediate hosts is well known due to reports in slaughterhouses while human reports are of discussed value. This is due to underreporting of cases and few epidemiological studies make it difficult to assess the situation of echinococcosis in the population. Whereas cattle infection rate is more or less stable around 12% of the slaughter animals, in sheep there has been an increasing number in the last five years. Some efforts have been done to control the zoonosis but no effective results were obtained so far. Probably educational efforts to change human practices (feeding dogs with raw viscera), periodic treatment of dogs with praziquantel and joined actions with slaughterhouses could bring more attention to improve some control measures.

Echinococcus granulosus sensu lato GENOTYPES IN DOMESTIC LIVESTOCK AND HUMANS IN GOLESTAN PROVINCE, IRAN

Cystic echinococcosis (CE) is a globally parasitic zoonosis caused by larval stages of Echinococcus granulosus. This study investigated E. granulosus genotypes isolated from livestock and humans in the Golestan province, northern Iran, southeast of the Caspian sea, using partial sequencing data of the cytochrome c oxidase subunit 1 (cox1) and NADH dehydrogenase 1 (nad1) mitochondrial genes. Seventy E. granulosus isolates were collected from animals in slaughterhouses: 18 isolates from sheep, 40 from cattle, nine from camels, two from buffaloes and one from a goat, along with four human isolates (formalin-fixed, paraffin-embedded tissues) from CE patients of provincial hospitals. All isolates were successfully analysed by PCR amplification and sequencing. The sequence analysis found four E. granulosus genotypes among the 74 CE isolates: G1 (78.3%), G2 (2.7%), G3 (15%) and G6 (4%). The G1-G3 complex genotype was found in all of the sheep, goat, cattle and buffalo isolates. Among the nine camel isolates, the frequency of G1-G3 and G6 genotypes were 66.7% and 33.3%, respectively. All four human CE isolates belonged to E. granulosus sensu stricto. This study reports the first occurrence of the G2 genotype in cattle from Iran and confirms the previously reported G3 genotype in camels in the same country.

South american rattlesnake venom: its hemolytic power

The hemolytic power of rattlesnake venom (Crotalus durissus terrificus) was Studied. A high percentage of sample with negative hemolytic power was detected when sheep red blood cells were used. A large number of venoms with hemolytic power, though with a low hemolysis percentage, were detected when liquid, recently extracted venom was used. When crystallized venom was used under the same experimental conditions, a higher percentage ofpositivityfor hemolysis was obtained. When the results obtained on agar plates were compared to those obtained in test tubes, a large number of animals with a higher percentage of hemolysis were detected, though this value was not proportional to the number of animals showing positive plate hemolysis. When the hemolytic power of these venoms was tested on human red blood cells, a large percentage of animals with venoms having a low hemolytic power was also detected. Hemolytic power was much greater when human red blood cells were tested with crystallized venom. The preparation of red blood cells also had an important effect and the use of red blood cells from defibrinated blood is recommended. We conclude that rattlesnake venom has hemolytic power that increases when the venom is crystallized. Red blood cells should be properly preparedfor the lysis reactions. We suggest that the lytic power of the venom is related to venom concentration and to the purity of its fractions.

Mortalidade por doenças infecciosas e parasitárias em Salvador - Bahia: evolução e diferenciais intra-urbanos segundo condições de vida

Analisa-se a evolução da mortalidade por DIP em Salvador-BA e seus diferenciais intra-urbanos mediante estudo de série temporal e de agregados espaciais, nos anos noventa. O DATASUS e declarações de óbitos foram as fontes de dados. Na análise temporal, empregou-se mortalidade proporcional, taxa de mortalidade e razão de mortalidade padronizada (RMP). No estudo espacial, analisou-se as taxas de mortalidade por DIP segundo um índice de condições de vida (ICV). Entre 1991 e 1995, a mortalidade proporcional por DIP foi de 8,3% e o risco de morrer variou entre 55,9 e 34,0 por 100 mil habitantes. No período seguinte, a variação foi entre 52,8 e 41,1 por 100 mil habitantes. A razão de mortalidade padronizada por doenças infecciosas e parasitárias em 1998 foi de 1,3. As doenças infecciosas intestinais continuam sendo uma das principais causas de morte desse grupo. As áreas da cidade onde as condições de vida eram mais baixas concentravam as maiores taxas de mortalidade por DIP. A despeito do declínio, ainda existe um excesso de mortalidade por DIP em Salvador. O modelo de desenvolvimento do país e a reemergência de algumas doenças podem estar contribuindo para este padrão.

Association of ants (Hymenoptera: Formicidae) with bacteria in hospitals in the State of Santa Catarina

The objective of this study was to identify ant occurrence in hospital environments in the State of Santa Catarina, along with associated bacteria. Ants were collected monthly from five inpatient clinics in two hospitals in the municipality of Chapecó, from August 2003 to June 2004. They were collected under aseptic conditions using swabs moistened with sterile distilled water and put into test tubes containing BHI for microbiological analysis. After 24 hours, cultures were made in both 5% sheep blood and MacConkey agar, which were incubated for 24 hours at 35/37°C. The Gram characterization, culture identification and biochemical characterization followed standardized rules for clinical microbiology. Seven species of ants were identified, of which the most frequent were Monomorium pharaonis (71.5%) and Solenopsis saevissima (57%), and nineteen species of bacteria was isolated from hospital "A".

Characterization of a new coagulase-negative Staphylococcus species (Staphylococcus pettenkoferi) isolated from blood cultures from a hospitalized patient in Porto Alegre, Brazil

INTRODUCTION: Staphylococcus pettenkoferi was originally isolated and described by Trülzsch et al (2002). In this study, we characterized two isolates of this newly described species. METHODS: Blood cultures were initially processed using the BacT/ALERT® device, and the isolates were initially characterized using the Vitek2 identification system. RESULTS: The initial characterization revealed slow-growing Gram-positive cocci that formed opaque colonies on sheep blood agar. Other phenotypic/genotypic tests were performed. CONCLUSIONS: We would like to emphasize that this new staphylococcus species is phenotypically similar to other CoNS, especially S. auricularis. This could potentially lead to misidentification of these uncommon species.

Seroepidemiological monitoring in sentinel animals and vectors as part of arbovirus surveillance in the state of Mato Grosso do Sul, Brazil

INTRODUCTION: From February-September 2010, seroepidemiological surveys were conducted on non-human primates and transmitter vector capture was used to investigate the possible circulation of arboviruses in the municipalities of Bonito, Campo Grande, and Jardim, State of Mato Grosso do Sul, Brazil. METHODS: A total of 65 primates from the wild and captivity were used, and potential vectors were captured using Castro and dip nets. Serum samples were tested at the Instituto Evandro Chagas, State of Pará, using the hemagglutination inhibition test to detect total antibodies against 19 different arboviruses. Virus isolation was attempted from serum samples and arthropod suspensions using newborn mice and the C6/36 cell line clone. In addition, identification of the vector species was conducted. RESULTS: From the 19 serum samples from Campo Grande, 1 sample had a 1:20 titer for Flavivirus. From the 35 samples collected in Bonito, 17 samples had antibodies to arboviruses, 4 (11.4%) were positive for Alphavirus, and 5 (14.2%) were positive for Flavivirus. Monotypic reactions were observed for the Mayaro (n = 10) and Oropouche (n = 5) viruses, and 6 (17.1%) samples had titers for >1 virus. We captured 120 Culicidae individuals that were potential arbovirus transmitters in Jardim; however, all the samples were negative for the viruses. CONCLUSIONS: Mato Grosso do Sul has a variety of vertebrate hosts and transmission vectors, thereby providing ideal conditions for the emergence or reemergence of arboviruses, including some pathogenic to human beings.

Molecular identification of the agent of Q fever – Coxiella burnetii – in domestic animals in State of Rio de Janeiro, Brazil

Introduction Over the last recent years, the number of Q fever cases have has increased throughout the world. An epidemiological investigation was performed in the area in which the first molecular documentation of Q fever in Brazil was previously reported. Methods Indirect immunofluorescence assay (IFA) and PCR of Coxiella burnetii targeting the htpAB gene were performed in samples from 14 dogs (blood); 1 cat (blood); 10 goats (blood, milk, vaginal swab and anal swab); 3 sheep (blood); and 2 horses (blood). Results Two dogs, two sheep and five goats were seroreactive. DNA was amplified from 6 milk and 2 blood samples from goats and from dogs, respectively. The sequence of the amplicons exhibited 99% sequence similarity with the homologous sequence of the htpAB gene of C. burnetii RSA 331 (GenBank - CP000890). Conclusions The results confirm C. burnetii infection in animals in Rio de Janeiro and reinforce the need for the surveillance of Q fever in Brazil.

Leptospirosis in animals and human contacts in Egypt: broad range surveillance

INTRODUCTION: Leptospirosis is a re-emerging zoonotic disease of humans and animals worldwide. The disease is caused by pathogenic species of the genus Leptospira. These organisms are maintained in nature via chronic renal infection of carrier animals, which excrete the organisms in their urine. Humans become infected through direct or indirect exposure to infected animals and their urine or through contact with contaminated water and soil. This study was conducted to investigate Leptospira infections as a re-emerging zoonosis that has been neglected in Egypt. METHODS: Samples from 1,250 animals (270 rats, 168 dogs, 625 cows, 26 buffaloes, 99 sheep, 14 horses, 26 donkeys and 22 camels), 175 human contacts and 45 water sources were collected from different governorates in Egypt. The samples were collected from different body sites and prepared for culture, PCR and the microscopic agglutination test (MAT). RESULTS: The isolation rates of Leptospira serovars were 6.9%, 11.3% and 1.1% for rats, dogs and cows, respectively, whereas the PCR results revealed respective detection rates of 24%, 11.3% and 1.1% for rats, dogs and cows. Neither the other examined animal species nor humans yielded positive results via these two techniques. Only six Leptospira serovars (Icterohaemorrhagiae, Pomona, Canicola, Grippotyphosa, Celledoni and Pyrogenes) could be isolated from rats, dogs and cows. Moreover, the seroprevalence of leptospiral antibodies among the examined humans determined using MAT was 49.7%. CONCLUSIONS: The obtained results revealed that rats, dogs and cows were the most important animal reservoirs for leptospirosis in Egypt, and the high seroprevalence among human contacts highlights the public health implications of this neglected zoonosis.