Can my child get vaccinated if she's sick?
Kids can get vaccinated if they have the sniffles, even a low-grade fever. But reschedule if your child is really under the weather. Vaccines won't make her worse, but they also won't be as effective because her immune system is too busy fighting her current infection to produce the desired vaccine antibodies. If your child has a compromised immune system due to cancer, HIV, or immune-suppressing medication, she should skip live-virus vaccines like the MMR or chickenpox because they could make her ill. Kids with food allergies may also need to avoid certain vaccines that contain eggs (influenza), gelatin (MMR), or yeast (hepatitis B).