This fever is highly contagious, and it’s most common in children 6 months to 3 years old during spring and fall. However, it might happen all year-round. This type of fever is most prevalent in children under 2 years old but it might happen to children up to 3 years old. A rash usually appears after 3 days. Your child will loose appetite and become irritable. Febrile seizures may also occur. If blister and spots are present it means it’s infectious. Your child’s temperature can either drop suddenly or rise quickly. Just remember that the ‘three day fever’ it’s not rubella although their symptoms are very similar. There is a vaccine against rubella. Going back to the three day fever (Roseola). Usually the fever ends the same day a pink rash appears. Take your child’s temperature with a good hygiene non-evasive non-contact thermometer. Contact your physician immediately if symptoms worsen. Do not give medicine to babies younger than two months old. Ask your doctor first. The right dosage of medicine depends on your child’s weight and age. Check the package label. You should not give aspirin to your child as it might cause Reye's syndrome. This illness (Reye's syndrome) can lead to death. Give your child fluids: water, juice, soup to prevent dehydration. Lots of rest, dress him/her in light pajamas, and if your child has chills just give him/her an extra blanket until it stops.