Impaired immune response in severe human lower tract respiratory infection by respiratory syncytial virus.

Background: Respiratory syncytial virus (RSV) is a major cause of acute lower respiratory infection in infants. The immune response plays a leading role in the severity of the disease. We hypothesized that severe RSV disease is associated with an impaired immune response characterized by low circulating T lymphocytes and plasma cytokine concentrations.

Population-based prevalence and age distribution of human papillomavirus among women in Santiago, Chile.

Unlabelled: More than 18 types of human papillomavirus (HPV) are associated with cervical cancer, the relative importance of the HPV types may vary in different populations.

Objective: To investigate the types of HPV, age distribution, and risk factors for HPV infection in women from Santiago, Chile.

Methods: We interviewed and obtained two cervical specimens from a population-based random sample of 1,038 sexually active women (age range, 15-69 years).