Mild infections are common during childhood. It’s not unusual for a child to see their doctor four times before they turn 1 because of bugs they’ve picked up. Most childhood infections can be managed safely at home, but parents often face a difficult decision if they suspect a more serious illness, about whether they need to get medical help.

Researchers have come to the aid of worried parents by coming up with a checklist of the symptoms we should take most seriously. The researchers call them “red flag” symptoms, and they’re the factors most likely to indicate a dangerous infection. The warning signs are:

• A blue or purplish tinge to the child’s skin, often around the fingernails or the mouth
• Rapid breathing
• Poor blood flow to the hands and feet. Your child’s hands or feet might feel much colder than usual, or their fingernails might take longer than a couple of seconds to turn pink again after being squeezed
• A rash caused by broken blood vessels under the skin. This kind of rash can be a symptom of meningitis. Some rashes will go away if you press them, but this kind won't. You can check by rolling a glass over the rash
• Drowsiness or loss of consciousness
• A seizure
• A fever measuring over 104 degrees Fahrenheit.