Vaccine Preventable Disease

Add-Vacc is an unblinded cluster-randomised trial (CRT) with two arms: (i) the national HPV vaccination programme (girls aged \~14 years, control arm) and (ii) the national programme plus single-dose male HPV vaccination given to a multi-year cohort of boys (intervention arm). The CRT will be conducted in 26 communities/clusters (13 per arm) in northern Tanzania. Boys aged 14 to 18 years in the intervention arm will receive one dose of the 4-valent HPV vaccine (Gardasil®) that protects against HPV 6, 11, 16, and 18. Population genital HPV prevalence in 18 to 21-year-olds will be compared between intervention clusters (female and male vaccination) and control clusters (female vaccination only) at 3 years after the intervention. Blood sampling for immune responses and adverse event data collection will be performed in a subset of 200 male subjects in selected intervention clusters.

In Africa, the mortality from infectious diseases remains high. The investigators have discovered that live vaccines such as the BCG vaccine against tuberculosis and the measles vaccine can strengthen resistance to other infections: they have beneficial "non-specific effects". The investigators have now seen signs that these non-specific effects for children are stronger if their mother has been given the same vaccines. In Africa, BCG vaccine is recommended at birth and measles vaccine at 9 months of age. They are not used beyond childhood. The investigators will randomize 2400 women to BCG vaccine, measles vaccine, or placebo. The investigators will further randomize their children to an extra early measles vaccine or placebo. The investigators will assess which of the resulting six vaccination schedules are best for women's and children's protection against measles, for the child's immune system, and for general health. The project will be the first in the world to investigate the importance of vaccinating women with live vaccines.