A sickness that affected more than 100 Box Elder students and caused Box Elder Schools to close Tuesday and Wednesday is most likely the result of influenza virus, a health specialist with the state Department of Public Health and Human Services said.
"We have no reason to doubt this is influenza based on what other places (in Montana) have experienced this year," said Jim Murphy, the state communicable disease surveillance officer.
The flu virus is hitting the state earlier than normal this year, he said, and has been working its way east from western Montana.
The cases have officials increasingly worried that a major flu outbreak could occur in Montana this winter.
There have been 10 flu cases documented in Hill County since Nov. 18. Three confirmed cases in the Box Elder and Rocky Boy area involved a 4-month-old, an 8-year-old, and a 14-year-old. Cindy Smith, the Hill County director of nursing, said she did not know whether either of the two older children are Box Elder students.
"That's really early in the flu season to come to Havre and Hill County," she said.
Cascade County already has 23 confirmed cases of flu. Cases were reported even earlier in Missoula.
So far, all reported flu cases have been Influenza A, which is more severe than the B strain, Murphy said.
In Colorado, four children have died of influenza, officials said Wednesday.
''It is a very high concern,'' said Murphy, and Montanans need to take the flu seriously.
''Some 115 Montanans die each year from flu, and this season the number may be higher,'' he said.
He said the flu strains now circulating across the country are some of the most severe.
Murphy said Janet Runnion, the public health nurse supervisor at the Rocky Boy Clinic, told him late last week that many students at Box Elder had come down with a respiratory illness, and that the clinic had confirmed its first case of influenza. Runnion did not say whether that case was one of the sick Box Elder students, but Murphy said the existence of the virus makes it likely that that's what attacked Box Elder students and faculty late last week.
Information from The Associated Press was used in this story.