Back-to-school time often means that kids bring home germs and illnesses. It’s just a fact of life. Schools are breeding grounds for infections. Germs easily go from person to person because kids are in such close proximity to each other. They are also sharing classroom equipment and supplies, which helps pass along germs. This close proximity can also lead to injuries. In fact, 40% of school-aged children miss three or more school days a year due to illness or injury.

With time, your child will develop immunity to many infectious diseases. But in the meantime, you need to help minimize the effect on your family. Hand washing is one of the most effective ways to prevent the spread of germs. If everyone practices proper hand washing, the whole school community stays healthier. Another key is keeping sick kids at home. They can return to school when they’re fever-free for 24 hours without medicine and they’re eating and drinking normally.

Here are some of the most common illnesses and injuries that happen at school. Learn what you can do to help your child and your family stay healthy this school year.

Cold and Flu

Cold viruses are the most common and most contagious school illness. Across the nation, kids miss nearly 22 million school days each year due to colds. Kids tend to get more colds than adults and their symptoms tend to be more severe. If your child doesn’t have a fever, it’s probably fine to go to school. But you need to teach your child how to avoid spreading germs. Make sure your child knows to cough and sneeze into a tissue or elbow if no tissue is available. And wash hands afterward.

The influenza virus is another respiratory virus that can wreck havoc during the school year. The flu is more intense than colds. Your child will have a high fever—101 degrees or higher—and will be unusually tired and have a dry cough. The flu also tends to keep kids out of school longer than a cold. The flu causes kids to miss 38 million school days each year. 

With both colds and flu, prevention is key. Teach your child to keep his or her fingers and hands away from the mouth, nose and eyes. And wash hands frequently with warm, soapy water. It’s also important to get the flu vaccine each year. The Centers for Disease Control and Prevention (CDC) recommends everyone six months of age and older gets vaccinated. Getting vaccinated helps protect your child. It also helps prevent spreading the flu virus to kids at high risk of flu complications.

Stomach Flu

Stomach flu really isn’t the flu. The influenza virus causes the flu. Gastroenteritis is the real name for what people call the stomach flu. And a wide variety of viruses cause gastroenteritis, including rotaviruses, noroviruses, and certain adenoviruses. These viruses infect the lining of the digestive tract, causing stomach pain, vomiting, and diarrhea. The biggest worry with gastroenteritis is dehydration. You don’t need to restrict food, but make sure your child drinks plenty of fluids.

Gastroenteritis spreads from close contact with someone who already has it. It can also spread through contaminated food and beverages. To avoid it, your child should always wash their hands after using the bathroom and before eating. You should also teach your child to avoid sharing drinks, eating utensils, and toothbrushes. And always eat food off of clean surfaces.

Head Lice

Head lice are tiny parasitic insects that live on the scalp. They feed on blood and cause intense itching. They don’t spread disease, but they can cause a secondary infection when kids scratch their scalp. The most common way to get head lice is from head-to-head contact with someone who has them. Head lice can also spread via personal items, such as hats, brushes, hair accessories, and bed linens.

Head lice infestations are most common in kids three to 11 years old and their caregivers. Kids of this age frequently play in ways that lead to close contact. They may also be sharing personal items and storage spaces at school. If your child gets head lice, it doesn’t mean your family is dirty. It simply means that your child came in contact with someone else who had head lice.