The Centers for Disease Control and Prevention (CDC) is warning of an increase in dengue fever cases in popular spring break destinations. The agency has issued a health alert, noting that dengue activity remains high in some parts of the US and globally. The CDC advises travelers to take precautions to avoid mosquito bites, such as using insect repellent and wearing protective clothing. Many countries have reported a higher number of dengue cases, and several have reported higher-than-expected numbers among American travelers returning to the US.