RESUMO
Enterococci are commonly found in the environment and humans as a part of the normal microbiota. Among these, Enterococcus faecalis and Enterococcus faecium can convert into opportunistic pathogens, making them a major cause of nosocomial infections. The rapid diffusion of vancomycin-resistant strains and their impact on nosocomial settings is of considerable concern. Approximately one-third of the E. faecium infections in Italy are caused by vancomycin-resistant strains. This study explored the hypothesis that the oral cavity could represent a silent reservoir of virulent enterococci. A sample of 862 oral flora specimens collected from healthy human volunteers in Central Italy was investigated by real-time PCR to detect E. faecalis and E. faecium, as well as the genetic elements that most frequently determine vancomycin resistance. The prevalence of E. faecalis was 19%, a value that was not associated with alcohol consumption, tobacco smoking, or age of the subjects. Less frequently detected, with an overall prevalence of 0.7%, E. faecium was more common among people older than 49 years of age. The genes conferring vancomycin resistance were detected in only one sample. The results indicate that the oral cavity can be considered a reservoir of clinically relevant enterococci; however, our data suggest that healthy individuals rarely carry vancomycin-resistant strains.
RESUMO
Oral cavity and oropharynx cancer associated with human papil loma virus infection, particularly in young people who are continuously exposed to this virus, is a serious public health problem worldwide, especially for high-risk strains that are most associated with premalignant lesions and tumors. These neoplasms remain asymptomatic for a long time and, when they occur, they are already at an advanced stage. If diagnosed and treated early, oral cancer induced by human papilloma virus allows for high survival, as it often has a more favorable prognosis than oral cancers not directly related to viral infection. In this study, the presence of different high-risk and low-risk HPV strains was investigated to assess the epidemiological status in a population of healthy individuals. Two types of samples, one from the tonsils and one from the base of the tongue, were collected from 2015 healthy individuals of different sex and age. A total of 1885 DNA samples belonging to 1285 patients were tested for the presence of 11 high-risk HPV types plus 4 low-risk HPV types using real-time PCR. Of the patients' DNA samples screened for 15 HPV types, only four samples were positive, all of which were taken from male smokers. These results indicate that newly acquired oral oncogenic HPV infections in the healthy population are rare and, in many cases, controversial. Therefore, more studies are needed to ensure fewer variations in outcomes and a greater clarification of HPV infection and its prevalence in the oropharynx of the healthy population, and to guide efforts to prevent the development of this infection which, if undiagnosed, can lead to the onset of malignant tumors in the oral cavity.