The accurate diagnosis of pneumococcal disease has frequently been hampered not only by the difficulties in obtaining isolates of the organism from patient specimens but also by the misidentification of pneumococcuslike viridans group streptococci (P-LVS) as Streptococcus pneumoniae. This is especially critical when the specimen comes from the respiratory tract. In this study, three novel real-time PCR assays designed for the detection of specific sequence regions of the lytA, ply, and psaA genes were developed (lytA-CDC, ply-CDC, and psaA, respectively). These assays showed high sensitivity (<10 copies for lytA-CDC and ply-CDC and an approximately twofold less sensitivity for psaA). Two additional real-time PCR assays for lytA and ply described previously for pneumococcal DNA detection were also evaluated. A panel of isolates consisting of 67 S. pneumoniae isolates (44 different serotypes and 3 nonencapsulated S. pneumoniae isolates from conjunctivitis outbreaks) and 104 nonpneumococcal isolates was used. The 67 S. pneumoniae isolates were reactive in all five assays. The new real-time detection assays targeting the lytA and psaA genes were the most specific for the detection of isolates confirmed to be S. pneumoniae, with lytA-CDC showing the greatest specificity. Both ply PCRs were positive for all isolates of S. pseudopneumoniae, along with 13 other isolates of other P-LVS isolates confirmed to be non-S. pneumoniae by DNA-DNA reassociation. Thus, the use of the ply gene for the detection of pneumococci can lead to false-positive reactions in the presence of P-LVS. The five assays were applied to 15 culture-positive cerebrospinal fluid specimens with 100% sensitivity; and serum and ear fluid specimens were also evaluated. Both the lytA-CDC and psaA assays, particularly the lytA-CDC assay, have improved specificities compared with those of currently available assays and should therefore be considered the assays of choice for the detection of pneumococcal DNA, particularly when upper respiratory P-LVS might be present in the clinical specimen.

Despite recent advances in food production technology, food-borne diseases (FBD) remain a challenging public health concern. In several countries, including Brazil, Clostridium perfringens is among the five main causative agents of food-borne diseases. The present study determines antimicrobial activities of essential oils of six condiments commonly used in Brazil, viz., Ocimum basilicum L. (basil), Rosmarinus officinalis L. (rosemary), Origanum majorana L. (marjoram), Mentha × piperita L. var. Piperita (peppermint), Thymus vulgaris L. (thyme) and Pimpinella anisum L. (anise) against C. perfringens strain A. Chemical compositions of the oils were determined by GC–MS (gas chromatography–mass spectrometry). The identities of the isolated compounds were established from the respective Kováts indices, and a comparison of mass spectral data was made with those reported earlier. The antibacterial activity was assessed from minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) using the microdilution method. Minimum inhibitory concentration values were 1.25 mg mL−1 for thyme, 5.0 mg mL−1 for basil and marjoram, and 10 mg mL−1 for rosemary, peppermint and anise. All oils showed bactericidal activity at their minimum inhibitory concentration, except anise oil, which was only bacteriostatic. The use of essential oils from these common spices might serve as an alternative to the use of chemical preservatives in the control and inactivation of pathogens in commercially produced food systems.

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Hepatitis E virus (HEV) is highly disseminated among swine herds worldwide. HEV is also a threat to public health, since particularly genotypes 3 and 4 may cause acute hepatitis in human beings. No previous studies were done on the occurrence of HEV in environmental samples in Rio Grande do Sul, Brazil. In the present study, reverse transcriptase-polymerase chain reaction (RT-PCR) was employed to detect the presence of HEV in swine feces and in effluents from slurry lagoons in farms located in the municipality of Teutônia, inside the area of swine husbandry in the state. Pooled fecal samples from the floor of pig barns from 9 wean-to-finish farms and liquid manure samples were collected from the slurry lagoons from 8 of these farms. From the pooled fecal samples, 8/9 were positive for the HEV ORF1 gene by RT-PCR; all the slurry lagoon samples were positive for HEV RNA (100%). The identity of the HEV ORF1 amplicons was confirmed by sequencing belonging to HEV genotype 3, which was previously shown to be circulating in South America.Keywords: Hepatitis E virus, swine HEV, slurry, zoonosis RESUMOO vírus da hepatite E (HEV) é altamente disseminado entre rebanhos suínos no mundo todo. O HEV é também uma ameaça à saúde pública, já que os genótipos 3 e 4 podem causar hepatite aguda em seres humanos. Não há estudos anteriores sobre a ocorrência de HEV em amostras ambientais no Rio Grande do Sul. No presente estudo, empregou-se transcrição reversa e reação em cadeia da polimerase (RT-PCR) para detectar a presença de HEV em fezes de suínos e efluentes de lagoas de chorume em fazendas localizadas no município de Teutônia, representativo da região de maior produção de suínos no estado. Pools de amostras fecais foram coletadas a partir do chão de galpões de suínos provenientes de 9 propriedades de terminação; outra amostra de esterco líquido foi coletada das lagoas de chorume de 8 dessas fazendas. A partir das amostras fecais reunidas, 8/9 foram positivas para o gene ORF1 de HEV por PCR convencional; todas as amostras de lagoas de chorume foram positivas para RNA de HEV (100%). A identificação dos produtos de amplificação de HEV ORF1 foi confirmada por sequenciamento pertencente ao HEV genótipo 3, o qual foi previamente detectado na América do Sul.