What We're Following This Evening

How Zika works: The U.S. Centers for Disease Control and Prevention is investigating 14 new reports of possible Zika transmission through sexual contact, CNN reports. The potential cases “suggest sexual transmission may be a more likely means of transmission for Zika virus than previously considered,” the CDC said. The virus, usually contracted through mosquito bites, was sexually transmitted in the U.S. for the first time earlier this month.

The SCOTUS scuffle: In the hours after Antonin Scalia’s death earlier this month, Senate Republicans said his Supreme Court seat should be filled by the next president, and signaled that they’d block any nomination from President Obama. They’ve made that pledge official now. Russell explains.

Speaking of Scalia: The AP, citing a doctor’s letter, reports the late justice suffered from obesity, artery disease, and diabetes. Scalia’s personal physician and family had said he died of natural causes, but his death generated conspiracy theories promoted by “truthers” and even a presidential frontrunner.

The Nevada caucus: It’s happening, and it’s going to be a late one: Results aren’t expected before midnight in the Eastern time zone. Donald Trump, fresh off consecutive, double-digits wins in South Carolina and New Hampshire, is the favorite. But because of Nevada’s caucus process and its relatively recent entry into the early voting rotation, polling is limited and prediction is tricky. Follow along with our politics team here.

News from this afternoon here.