How do you know if a person has a sudden illness that might need medical attention?

You can identify a sudden illness that may require medical attention by observing symptoms such as severe pain, difficulty breathing, confusion, persistent vomiting, or noticeable changes in consciousness. Other warning signs include high fever, sudden weakness or numbness, and any unusual behavior that deviates from the person's normal state. If these symptoms arise abruptly or are severe, it's important to seek medical help immediately. Always err on the side of caution when it comes to health concerns.