Talk these days of quarantines revolves around Ebola, but one South Carolina family has voluntarily blocked themselves off from the outside world—not to protect others, but to protect their 4-year-old daughter, Eliza, who suffers from the most severe form of a rare genetic disorder called Sanfilippo syndrome.

The metabolic disorder, diagnosed in 2013, is already slowing Eliza's ability to talk, reports People, and will eventually rob her of the ability to walk, eat, and finally, to breathe.

Most people with the syndrome die by their teen years, so while the isolation—now in its fifth month—is taking its toll, the family says it's worth it.

"We'll do this as long as it takes," says dad Glenn O'Neill. Their aim is to keep her healthy so she can take part in a clinical trial, likely early next year, they hope will lead to a cure.

"We have heard stories from families of older kids with Sanfilippo where a sickness at this stage started the downward slide even faster and they never fully recovered," says Glenn O'Neill.

Because even fairly benign viruses like the common cold can exacerbate Eliza's symptoms and speed the progression of the disorder, mom Cara O'Neill has quit her job as a pediatrician and Glenn O'Neill now works from home, while Eliza and her 7-year-old brother, Beckham, are home-schooled.

Though the family does go out on a rare occasion to, say, a deserted beach or field, reports the New York Daily News, they have groceries delivered to their doorstep and wipe all incoming packages with antibacterial wipes.

So far it's worked; Eliza hasn't gotten sick. The O'Neills' fundraising website is here. (Another sufferer of a rare genetic disorder was able to give birth.)

This article originally appeared on Newser: Why This Family Is 150 Days Into Quarantine

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