Dad got sick first. It was about 4 a.m. New Year's Day when Mike O'Rourke woke in his Chevy Chase home feeling horribly, terribly ill. He staggered to the bathroom, got on his knees and threw up. For the next seven hours he made trips to the toilet almost every 15 minutes, until finally he gave up going back to bed, and simply slumped on the bathroom tile in misery.

From their bed, O'Rourke's wife, Betsy, listened in horror. "It was truly violent," she says.

So it began. Betsy worried. Ten-year-old Aimee, the O'Rourke's older child, worried. Eight-year-old Peter made a get-well card, which he left by his dad's prostrate body. At one point, when he felt a brief burst of energy, Mike raised his pounding head from the bowl to find Peter's note. "Get Well Dad, from Peter," it read. The card was illustrated with a picture of a stick figure retching his guts out.

"I wanted to draw a toilet," Peter explains, "but it was too hard."

The O'Rourkes thought Mike had food poisoning. They thought the rest of the family was safe. They were wrong.

Early the next morning, Betsy woke to a tugging on her shoulder. It was Peter in pajamas, looking wan. "Mom," he said, "I think I'm going to throw up." Betsy looked at Mike. And they knew. It was the flu.

The flu, oh, the dreaded flu. Its symptoms can vary, frequently attacking the lungs, and sometimes the tummy, but it has filled emergency rooms in the Washington area, causing hospital overflow and a shortage of beds. It has cleared the pharmacy shelves of over-the-counter remedies. Most agonizing, it has brought whole families low. Like the O'Rourkes.

The bug descended upon the O'Rourke household with a vengeance this past week, leaving no one untouched. By the time the vile virus had finished wreaking havoc, it had attacked all four family members, Betsy's sister visiting from Malta, who had spent one night, and both Betsy's mother and her mother's husband, also from Malta, who had only dropped by the house for two hours. The poor international visitors were last heard from in a hotel room in New York City, where as of Friday they still were sweating out the result of having spent a few brief hours inside the contaminated zone.

Only the family's golden retrievers, Faith and Hope, escaped unscathed. Of course, they haven't been walked in a week.

"We have a big black 'X' on our door," Mike says. "Are you sure you want to come in?"

The house is approaching normal now. The unpleasant combination of previous aromas--Lysol mixed with stomach acid mixed with sweaty T-shirts and damp, crumpled sheets--has evaporated. Oh, but a few short days ago . . .

It was Mike on Saturday, Peter on Sunday, Betsy on Monday, Aimee on Tuesday. Each waiting their horrible turn. Mike ate lobster and crab and beer the night before he grew ill. Aimee dined on Thai food for her last meal, which soon returned.

"Yellow!" she says, "For a whole day! Then I had nothing more to throw up."

Their stomachs cramped. Their heads ached. Their fever-racked bodies sweated. They were dizzy. Tired, but unable to actually sleep. Noses ran. Piles of wadded up Kleenex grew.

"You're just laying there," Mike says. "You can't move. You're just moaning all the time."

Adds Betsy: "You get these horrible aches. You're really, really achy. It goes right into your bones."

At first, Betsy tried to take care of her brood. But no one wanted anything anyway. No one bothered to go downstairs. Most of the time, they didn't even bother to leave their rooms. By Tuesday night, all four family members were piled into one big bed.

Dirty sheets? Who cares. No showers? Who cares. It was group misery.

An entire can of Lysol was used in three days in a vain attempt to both disinfect and stamp down the terrible smells. All three bathrooms went low on toilet paper.

"This flu," Mike says, "is brought to you by Charmin."

They didn't eat. Forget juice. The famous flu-inspired BRAT diet--bananas, rice, applesauce, toast? Forget that, too. Who wants to eat anything that's just coming right back out in one form or another?

"Eventually," Betsy says, "we had soup. Our nanny made it. She calls it Filipino penicillin. I don't know how she made it, but it was pretty good."

For Mike, the low point came in the beginning--his seven-hour bathroom marathon. Of course, he didn't feel so great, either, when the babysitter ran out of gas in a driving rainstorm and he had to take off the gym shorts and T-shirt he'd been living in for three days and go out to her aid. Standing in a downpour, his body soaked and aching, his chest congested, his head light, a gas can in his hands, he felt like a man facing Armageddon.

For Betsy, it came Wednesday night, after she ventured out to work at the Travel Industry Association, where she is senior vice president for marketing. She thought it would be a one-hour meeting she couldn't miss, and wound up at the office all day. She walked in the door that night and declared it a mom-free zone--she was no longer waiting on her sick charges. She was getting waited upon. She went straight to bed.

For Peter, a third-grader at Blessed Sacrament, it was watching his father so sick the first morning. For Aimee, who's in the fifth grade, it was probably being last. Being the one who had to wait and watch, knowing all along that she had to be next.

"It's the worst the first day," Aimee said. "I knew that from my dad."

The air in the house got thick and heavy and stifling as four people breathed the same germs, sharing them back and forth. They longed for clean sheets, hot baths, the merest hint of an appetite. To get out of the house. To get away from each other.

"After four days of being in the house together, tensions start to run a little high," Mike says, diplomatically.

Aimee's a kicker in her sleep. The dogs need more attention. Who is going to replace the empty toilet paper rolls? And Mike, well, everybody blamed him for getting the rest of the family sick. After all, he did start it.

Mike returned to his job as a sales manager at WTOP on Wednesday, where he hid behind closed doors, still wheezing and sniffling and generally sounding like death. Not that any of his colleagues came close enough to hear. Oh no, they flattened their backs against the wall in the hallways when Mike walked by.

"Everyone's avoiding me," he says. "They don't want to get close."

They also commented on his weight loss, one colleague puckering her cheeks to indicate how much thinner he looks. Mike lost 15 pounds during his ordeal. Betsy reports she lost six. For Aimee, three. By Thursday night, they are able to joke about this, to start talking about the "positive effects" of the flu. Not one to be left out, Peter races up the stairs to check the scale.

"I lost 10!" he announces, triumphantly.

"Just call it the diet to start the New Year," Betsy says.

Mike grimaces.

CAPTION: The O'Rourke family can now smile about the days they spent sick together.