Editor's note: Lab results determined the death at the Alaska Native Medical Center early this week was not flu related. A rapid influenza test initially indicated a positive flu test, but the results of the in-depth test by the state virology lab found that test was incorrect.

A young adult who tested positive for what could be the H1N1 flu strain has died at the Alaska Native Medical Center in Anchorage. Flu season is impacting Alaska later than usual this fall, and two types of influenza have been identified by the state -- including H1N1, which frightened people here and Outside four years ago when it emerged as a pandemic.

The hospital sent out an email Wednesday informing employees of the death of a young adult who had tested positive for what in-depth results could reveal as H1N1. The email also noted that some of the patients admitted to the medical center during the past week who tested positive for flu are "seriously ill."

"The predominant strain in the cases appears to be the 2009 H1N1, which is included in the 2013-14 influenza vaccines," the email said.

The state Department of Health and Social Services will investigate the death, as it does many influenza-related deaths, and determine whether flu alone killed the patient or if an underlying illness worsened the patient's condition.

Dr. Michael Cooper, the infectious disease program director for the state, said it is too early to tell if H1N1 will be the predominant strain in Alaska this season. There are only a small number of confirmed cases statewide, but they've mostly been H1N1, he said.

Since the start of flu season in September, 13 cases have been reported to the state Department of Health and Social Services. Eleven of them have been H1N1, which in 2009 earned the title swine flu because it was often found among pigs. Ten of the cases were in the Anchorage and Matanuska-Susitna Valley areas, in the state's most populous region. The remaining case came from the Gulf Coast region.

The Alaska Native Medical Center has reported five flu cases to the department so far. The patient who recently died is the only one who tested positive for influenza A, the predominant straing of which is H1N1, using a rapid test that's in place at the hospital. Results from a more in-depth lab test is still pending.

Luckily, health officials recognized that H1N1 would once again begin circulating this year, as the strain skipped a season. Dr. Jay Butler, the director of the Native hospital's division of community health services, said science does not yet have an answer as why strains disappear one season, then come back the next.

Butler said that the flu is common among children, but H1N1 was unusual for a pandemic in that it reportedly had a propensity to make kids sick. It's still too soon to say whether this characteristic stuck with the strain.

Alaska's first deaths from H1N1 occurred about one month after the pandemic was detected in the United States. In May of 2009, a 10-year-old boy and two middle-aged women from Alaska died after developing high fevers and increasing respiratory distress. During that first season, a total of 12 Alaskans succumbed to the illness.

H1N1 is part of the flu mix showing up in all regions this season, with 28 cases reported nationwide last week to the Centers for Disease Control (CDC) -- about one-fifth of the some 145 flu cases that have been positively confirmed by laboratory tests. Most of those cases are type A flu. Some, but not all, are tested for subtypes, which is how H1N1 is able to be tracked.

Some 3,000 to 49,000 people die from the flu each year, according to CDC estimates, said Jason McDonald, a spokesperson. Now that H1N1 is no longer a new phenomena, it's tracked like other cases of seasonal influenza. There's no way to know precisely how many people get sick and die from the illness, since health providers and states are not required to report on flu related deaths unless the patient is under the age of 18.

It's the time of year when flu cases increase, although flu is difficult to predict, said Donna Fearey, a nurse epidemiologist in the infectious disease program with the state of Alaska. There's no way to know how severe the flu will be or how long it will last, she said.

With cases starting to show up in Anchorage, Southeast, and other parts of the state, Fearey has a strong piece of advice: "Flu season is here. Get vaccinated."

The Alaska Native Medical Center has indicated it will set up walk-in flu clinics in the days ahead, and is limiting access to some areas of the hospital where babies, children and critically ill people are being cared for. See an information sheet on the flu in Alaska, here. For more information, click here.

Clarification: The text of this article has been updated to reflect that final test results determining the strain of flu that afflicted the patient who recently died were still pending.