Very common (These may occur in 1 in 10 doses or more of the vaccine): • Pain and redness at the injection site Common (These may occur in up to 1 in 10 doses of the vaccine): • Drowsiness, headache • Nausea 49 • Loss of appetite • Swelling or bruising at the injection site • Generally feeling unwell, tiredness • Fever equal to or greater than 37.5°C • Irritability Uncommon (These may occur in up to 1 in 100 doses of the vaccine): • Diarrhoea, vomiting, stomach pain • Rash • Aching muscles • Upper respiratory tract infection Rare (These may occur in up to 1 in 1,000 doses of the vaccine): • Swollen glands in the neck armpit or groin (lymphadenopathy) • Dizziness • Loss of skin sensitivity to pain or touch (hypoaesthesia) • Feeling of pins and needles (paraesthesia) • Hives, itching • Joint pain • Low blood pressure • Flu-like symptoms such as high temperature, sore throat, runny nose, cough and chills Very rare (These may occur in up to 1 in 10,000 doses of the vaccine): • Reduction in blood platelets, which increases risk of bleeding or bruising (thrombocytopenia) • Purple or red brown spots visible through the skin (thrombocytopenic purpura) • Swelling or infection of the brain (encephalitis) • Degenerative disease of the brain (encephalopathy) • Inflammation of nerves (neuritis) • Numbness or weakness of the arms and legs (neuropathy), paralysis • Fits or seizures • Swelling of the face, mouth or throat (angioneurotic oedema) • Purple or reddish-purple bumps on the skin (lichen planus), serious skin rashes (erythema multiforme) • Joint swelling, muscular weakness • Infection around the brain which may give severe headache with stiff neck and sensitivity to light (meningitis) • Inflammation of some blood vessels (vasculitis) • Serious allergic reactions (anaphylaxis, anaphylactoid reactions and mimicking serum sickness).