Ticks spread Rocky Mountain Spotted Fever and Lyme Disease in most areas of the United States. Mosquitoes spread viruses such as the West Nile virus. The newly introduced Middle East Respiratory Syndrome (MERS) started out as a viral disease of camels. Mosquito bites spread it to humans in the Middle East. Now infected travelers have started to bring the virus to other countries. The bites of local mosquitoes in these other countries can spread it.
Caring for Our Children 3rd edition, Standard 3.4.5.2 says “Insect repellents may be used with children in child care in areas of the country due to specific disease outbreaks and alerts.” If a health professional recommends using a repellent, DEET should be used for everyone but infants younger than 2 months of age. Do not use sunscreen-DEET products. You need to apply sunscreen more often than insect repellent.