Our long influenza nightmare is almost over.

After an unusually intense attack, this winter's nasty flu is easing its stranglehold on Arizona, finally allowing our frantic ERs to take a deep breath.

But it's leaving behind the highest number of confirmed flu cases in Pima County - at least 782 - since we began counting them.

That 782 is only a tiny fraction of the true flu numbers - just a snapshot, since the vast majority of cases go unreported and unconfirmed.

"This was a very long flu season. It hit its peak in February and stayed there for almost eight weeks - that's very unusual," said Lisa Hulette, epidemiologist at the Pima County Health Department.

"In most years, flu peaks for a much shorter period, maybe two to three weeks. But this was sustained, with a high number of cases. It was a struggle for our entire health-care system, especially the emergency departments."

It was not until the end of last week that Arizona's flu-severity status declined from "widespread" - the highest level - to "local" - meaning flu cases are significant now in only one area of the state, Maricopa County.

Last week, new flu cases there numbered 84, while new cases trickled down to only four in Pima County.

What we're seeing now as the season winds down is the milder type-B flu. The type-A strains dominated during the peak weeks, when people flooded the ERs and missed a week or more of work with severe illness.

By mid-February, county health officials were pleading with stricken patients to stay out of the ERs if at all possible, because they couldn't handle the load.

"This week, by Wednesday and Thursday - that's when we finally started to breathe around here," said Gerri O'Neill, director of emergency services at University Medical Center.

"Today (Friday) the wait is down to only four hours, so things are really improving, and we're feeling good about it. These are the first days of relief we've seen in a very long time."

O'Neill noted that this year's flu vaccine did not cover all of the flu strains that circulated this year, leaving even those who did get a shot vulnerable to certain forms of the virus.

"That didn't help," she said.

Starting to calm down as well is the city's largest ER, at Tucson Medical Center. During the peak flu period - from the first week in February through early April - TMC handled more than 300 emergency patients a day. That number has finally declined to about 250 a day.

"We are just normal busy now, instead of overrun," TMC spokesman Mike Letson said. "We have some breathing room."

Every year, the flu shot is designed to cover three flu strains - two type-A's and one type-B - most likely to show up that winter. This year, the shot gave almost no protection for the type-B strain that circulated, and only partial coverage for one of the type-A's.

It is the B strain that is blamed for two pediatric flu deaths in Arizona this year - an infant and a child younger than 10 years old, said state epidemiologist Ken Komatsu. Both died in March in Maricopa County, which tallied a total of 2,627 confirmed flu cases this season.

Although Pima County's case count of 782 hit a record for the five years since flu reporting started in 2003, the state notched an overall higher total two years ago, with 5,197 cases, compared with the total 4,854 cases this year in Arizona.

But that flu season peaked earlier, in December, and ended quickly, within a few weeks, making the impact less severe than this season's prolonged outbreak.

"This was a unique year," Komatsu said. "High case numbers for two months - that's what hit the hospitals so hard."

Across the country, most states are reporting some lingering flu activity, mostly at localized levels. Only the mid-Atlantic and New England states are still suffering widespread illness.