Investigators: Chris Blyth, Hannah Moore, Lea-ann Kirkham, Nick De Klerk
External collaborators: Heather Gidding (University of Sydney)
Respiratory, or chest, infections are a major cause of illness in children. Globally, chest infections are the most common reason for hospitalisation. In Western Australia, 1 in 15 children are admitted to hospital for a chest infection before their 5th birthday. The best way for preventing severe diseases from these infections is vaccination. There are now multiple vaccinations on the National Immunisation Program that target respiratory infections, such as the pneumococcal conjugate vaccine (PCV), diphtheria-tetanus-pertussis (DTPa), and seasonal influenza vaccines. These vaccines have shown health benefits through direct protection of the disease that they are designed to target. There is emerging data about the positive and negative impacts of vaccinations against other pathogens and diseases suggesting that immunological or microbiological interference is occurring. Given the complexity of the immunisation schedule, it is essential to understand how vaccinating against one pathogen may change the disease that we see caused by other pathogens. These are called “off-target” effects and are best identified when looking at whole populations. Understanding the off-target effects of vaccines has been recognised as an area of international importance and will contribute to developing the best and most cost-effective immunisation schedules possible.