First detection of kobuvirus in farm animals in Brazil and the Netherlands.

Animal kobuviruses have been described in pigs, cattle, sheep and bats in countries in Asia and Europe. The virus can be detected in fecal and serum samples of infected animals with or without diarrhea, but most of the clinical as well as epidemiological features of kobuvirus infection are still unknown. This study reports the first detection of kobuvirus in farm animals from Brazil and the Netherlands and the molecular analysis of the detected strains. In Brazil, 53% (61/115) of the pigs (suckling, weaned and sows) were shedding porcine kobuvirus in feces, while in the Netherlands 16.7% (3/18) of the tested weaned pigs were infected. Kobuviruses detected in fecal samples of pigs in Brazil showed association (p = 0.0002) with diarrhea. In pig serum, kobuvirus was detected at different ages (3, 21, 36, 60, 75, and 180 days), with an overall rate of 76.7% (23/30). The sequencing of amplicons detected in serum of pigs of different ages suggested reinfection and no persistent infection. Kobuvirus was also detected in sheep and cattle feces from Brazil and the Netherlands, respectively. Phylogenetic analyses of Brazilian and Dutch kobuviruses from pig, cattle and sheep revealed genetic variability, particularly in one strain detected in sheep feces, which was more closely related to human Aichi virus. The molecular and phylogenetic analyses performed with other published kobuvirus strains and the strains presented in this study, showed that, in most of the cases, kobuvirus seems to group according to host species, but not to geographical region of origin. The data presented in this study contribute to the comprehension of kobuvirus epidemiology and also to the molecular identification of kobuvirus strains circulating worldwide

EFEITO ADJUVANTE DO CLORETO DE DIMETILDIOCTADECILAMÔNIO EM PREPARAÇÕES DE TOXÓIDE TETÂNICO

Foram formuladas duas vacinas contendo a mesma concentração de toxina, com o intuito de se avaliar a habilidade do adjuvante cloreto de demetiloctadecilamônio (DDA cloreto) em potencializar a resposta imune em cobaias imunizada com o toxóide tetânico. A vacina A foi adsorvida com hidróxido de alumínio e a vacina B cmpreendia a associação do hidróxido de alumínio e DDA cloreto. Os títulos de antitoxina no soro dos cobaios imunizados foram quantificados por soroneutralização em camundongos frente a uma dose contendo 1 Lp/10 (limite paralítico) de toxina tetânica. A inclusão do DDA cloreto em vacinas constituídas por toxóide tetânico adsorvido com hidróxido de alumínio promoveu maior ativação das respostas imunes humoral e celular de cobaios, quando comparada à resposta imune dos animais que receberam o antígeno adsorvido apenas com o hidróxido de alumínio. Os animais recebedores da vacina B apresentaram títulos de anticorpos neutralizantes 2,66 vezes maiores que os que recebedores a vacina A, demonstrando a potencialização da resposta imune humoral promovida pelo DDA cloreto. A resposta imune celular, avaliada pela reação de hipersensibilidade cutânea tardia, foi 17,8 maior no grupo B. Esses resultados demonstram que o DDA cloreto é um potente ativador da resposta imune humoral e celular de cobaios imunizados com o toxóide tetânico. Adjuvant effect of dimethyl dioctadecyl ammonium chloride in tetanic toxoid preparations Abstract Two vaccines were formulated with the same concentration of antigen and different adjuvants to assess the performance of dimethyl dioctadecyl ammonium chloride (DDA chloride) in boosting the immune response in guinea pigs immunized with tetanic toxoid. Vaccine A was adsorbed with aluminum hydroxide and vaccine B contained an association of aluminum hydroxide and DDA chloride. The antitoxin titres in the immunized guinea pig sera were assessed serum neutralization in mice using a toxin containing one Lp/10 dose (paralytic limit). The inclusion of DDA chloride in vaccines made up of tetanic toxoid adsorbed with aluminum hydroxide causes a greater activation of the humoral and cell immune response in guinea pigs when compared with the animals which received the antigen adsorbed only with aluminum hydroxide. The animals which received vaccine B had 2.66 times more neutralizing antibodies than those which received vaccine A, showing the boosting of the humoral immune response caused by DDA chloride. The animals from group B also had a strong immune cell response by the delayed type hypersensitivity reaction, which was 17.8 times higher than group A. These results show that DDA chloride is a potent activator of the humoral and cell immune response in guinea pigs immunized with tetanic toxoid