NPR Health

Before Zika swept across most of Latin America and the Caribbean, the largest outbreak ever recorded had been in French Polynesia. Between 2013 and early 2014, researchers estimate nearly 20,000 people on the cluster of islands in the South Pacific were infected with the virus.

French Polynesia's brush with Zika underscores fears that the mosquito-borne virus could cause devastating neurological problems but it also offers insights into the disease — and hope that Zika can be contained.

The mayor of Hawaii County has declared a state of emergency on Hawaii's Big Island over an outbreak of mosquito-borne dengue fever.

The island has seen nearly 250 confirmed cases of the mosquito-borne virus since September 2015. State health officials first reported two cases that originated there in late October 2015, Mayor Billy Kenoi says in his declaration.

When Carolyn Coyne's lab at the University of Pittsburgh recently tried to order a sample of Zika virus from a major laboratory supplier, they were told it was out of stock.

"They are actually back-ordered until July for the virus," Coyne says. "At least that's what we were told." She ended up obtaining Zika from another source, and it arrived at her lab Tuesday.

Law enforcement officials would love to have a clear way to tell when a driver is too drugged to drive. But the decades of experience the country has in setting limits for alcohol have turned out to be rather useless so far because the mind-altering compound in cannabis, THC, dissolves in fat, whereas alcohol dissolves in water.

There's never a shortage of questions about the twists and turns of health coverage. Here are answers to recent questions from readers about premium tax credit repayments for marketplace plans, out-of-network emergency care and nursing home bills.

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