OBJECTIVE To determine whether BCG revaccination at 19 months of age reduces overall child mortality. DESIGN Randomised trial, with follow-up to age 5. SETTING A health project in Bissau, Guinea-Bissau, which maintains a health and demographic surveillance system in an urban area with 90 000 inhabitants. PARTICIPANTS 2871 children aged 19 months to 5 years with low or no reactivity to tub...

CONTEXT Although large-scale observational studies have demonstrated the effectiveness of influenza vaccination, no large studies have systematically addressed the clinical benefit of annual revaccinations. OBJECTIVE To investigate the effect of annual influenza revaccination on mortality in community-dwelling elderly persons. DESIGN, SETTING, AND PARTICIPANTS A population-based cohort stud...

BACKGROUND Influenza vaccination has been associated with a reduction in the number of hospitalizations for respiratory conditions in elderly persons over the period from 1996 to 2002. Little is known, however, about the effect of influenza vaccination on the whole range of severity of respiratory tract infections. METHODS We investigated the effect of annual influenza vaccination on the occu...

Bacillus Calmette–Guérin (BCG) vaccine provides good protection against disseminated mycobacterial diseases such as miliary tuberculosis, tuberculous meningitis, and leprosy [1, 2] but weaker protection against pulmonary tuberculosis, especially in rural areas near the equator [3]. In high-mortality countries, until a different vaccine is given, BCG vaccine also provides nonspecific (heterologo...

Seasonal influenza is a significant public health concern globally. While influenza vaccines are the single most effective intervention to reduce influenza morbidity and mortality, there is considerable debate surrounding the merits and consequences of repeated seasonal vaccination. Here, we describe a two-season influenza epidemic contact network model and use it to demonstrate that increasing...