Why is Dengue fever surging worldwide?

Climate change is fueling a global explosion of dengue fever as mosquitoes multiply in warmer, wetter weather. And now, public health officials are on high alert this travel season, bracing for the virus to crop up in more temperate regions, including the southernmost portions of the United States. Post reporters Lena Sun and Sarah Kaplan explain. Read more about their in-depth reporting, which brought health reporter Lena Sun to Puerto Rico in early June: Read more: Subscribe to The Washington Post on YouTube: Follow us: Twitter: Instagram: Facebook: