Vaxiboon-23 Vaccine 0.5 ml is an immunizing medicine used in the treatment of pneumococcal infections (infections of the ear, blood, brain and lungs). This is a vaccine which helps to develop immunity by starting a mild infection. It stimulates the body's immune system to make antibodies to prevent any upcoming infections. Common side effects include fever, injection site redness, rashes, decreased appetite, irritation, vomiting, and diarrhoea.