Aerosol exposure enhanced infection of low pathogenic avian influenza viruses in chickens.

To assess the impact of different routes of inoculation on experimental infection of avian influenza (AI) viruses in chickens, this study compared virus replication and cytokine gene expression in respiratory and gastrointestinal organ tissues of chickens, which were inoculated with four low pathogenic subtypes, H6N1, H10N7, H10N8, and H13N6 AI viruses via the aerosol, intranasal, and oral routes respectively. Aerosol inoculation with the H6N1, H10N7, and H10N8 viruses significantly increased viral titres and upregulated the interferon (IFN)-γ, interleukin (IL)-6, and IL-1β genes in the trachea and lung tissues compared to intranasal or oral inoculation. Furthermore, one or two out of six chickens died following exposure to aerosolized H6N1 or H10N8 virus respectively.

H9N2 avian influenza virus retained low pathogenicity after serial passage in chickens.

The H9N2 strains of avian influenza viruses (AIVs) circulate worldwide in poultry and cause sporadic infection in humans. To better understand the evolution of these viruses while circulating in poultry, an H9N2 chicken isolate was passaged 19 times in chickens aerosol inoculation. Whole-genome sequencing showed that the viruses from the initial stock and those after the 8th and 19th passages (P0, P8, and P19) all had the same monobasic cleavage site in the hemagglutinin (HA), typical for viruses of low pathogenicity.

Oral health knowledge and practices of dentists practicing in a teaching hospital in Nigeria.

Aim: To assess the oral health practices and knowledge of practicing dentists at a tertiary health institution in Nigeria, and the possible association of age and sex with caries prevention practices.

Methodology: A cross-sectional study was conducted. All practicing dentists in the institution were eligible to participate in the study.