From the closed door of the doctors' office, the line shivered across the parking lot, around the corner and two blocks along a side street before looping into a neighboring subdivision. We'd arrived an hour and 10 minutes before the clinic's scheduled start to find 20 families already there.

We set up in Camp Not-the-Flu, joining a community well equipped with cell phones, lawn chairs, blankets and breakfast biscuits. In this odd place, a child's tear-stained face usually meant success -- the elusive flu vaccine had been obtained. And that's what we were all waiting for.

Ever since the time our family recalls as the Plague Year, flu shots have been mandatory in our home. During that dreadful winter, my husband and all three boys shared a flu that became lingering bronchitis and left our kitchen counter cluttered with three different kinds of prescription cough syrups and an array of antibiotics.

My mother came to help and left hacking and feverish. My mother-in-law came to help and left hacking and feverish. My sister-in-law, who should have known better, was likewise rewarded for her efforts. By the time the 7-year-old who'd started it all finished up with a round of strep throat, I thought the local health department might order the house burned to the ground to stop the spread of infection.

Almost six weeks after palming that first too-warm forehead, only I emerged untouched by the bug but worn down from administering midnight nebulizer treatments, searching for the right flavor of fever reducer, and double-bagging used tissues as toxic waste. My hands were chapped from hot water and antibacterial soap.

Never again, I swore to myself, would I be near that much phlegm.

And so our pediatrician's annual flu shot clinic has become a ritual -- a crisp autumn morning, waiting with cheerful parents and fearful kids. No appointments taken but usually snacks and drinks for those in line. There was an air of camaraderie and shared stories of clinics past. Good times.

Until this year. There's nothing like a vaccine shortage to sap the fun out of an immunization clinic. And to leave even the best of us a little tightly wound.

Was that man helping the doctors set up coffee motivated by goodwill or the hope of nudging his family farther up the line? What about that woman slipping in the door ahead of everyone else? Was she really going to the bathroom or to lurk inside and then mingle into the crowd rather than waiting for 50 other families to stream in ahead of hers?

Two of our sons qualified for the shot because they are asthmatic, and the third was able to get the nasal mist while our doctor still had a supply. But I found myself unreasonably concocting a list of disqualifiers for other recipients.

If you're a dad who chain-smokes while describing your child's upper respiratory ailments, maybe you should pay extra.

If you're a kid skateboarding without a helmet in the pediatrician's parking lot, a two-page essay on why brain injuries can be worse than the flu should be required before getting your shot.

Even the usually bright chatter among those waiting was dimmed as parents worried how many would get in before the shots ran out.

I suspect this is how bank panics start.

Once the line began to move, we were through in 20 minutes. Forms filled out and money exchanged for punctured arms and a big sniff.

Heading back to the car, I studied a line that had grown since we joined it. Parents pushing strollers from several blocks away accelerated into a trot as they realized what they were up against. I have no idea how many were told their wait had been useless, but I'm glad I wasn't there to see it.

Last year, we learned flu shots don't always work. This year, we learned flu shots aren't always available. Next year, I hope for a return to the days when "flu shots" was just an entry I cross off my to-do list, somewhere between soccer practice and visiting the pumpkin patch.