Caused by the influenza virus, the flu is among the leading causes of illness in the country, according to the Department of Health (DoH).
The flulike illness surveillance map, which also tracks clinic visits for flu, shows that activity is high in 18 states, up from 9 in the previous week. This year we have had very little "B" but that's not to say we won't see it. "This flu season may have peaked earlier than past year, but generally the season lasts into April".
So far this flu season, Kansas has seen 11 deaths from the flu.
The US Centers for Disease Control and Prevention (CDC) said that children younger than 5 years and children of any age with certain long-term health problems are at high risk of complications such as pneumonia, bronchitis, and sinus and ear infections.
The flu-related death toll in Alberta has reached 25. "We'd like to have another 20 or 30 more if we could, particularly we need more representation in the north of the province", he said.
The flu season in Iowa this season is widespread, meaning "there's a fair amount of activity", Pedati said. This is the overall rate with a higher proportion of people who are 65 and older requiring hospitalization (38.3 per every 100,000), followed by children up to age 4 (26.5 per every 100,000).
As for whether this season has been weaker than others, Henry says it depends on how you look at it, pointing out younger people are better able to fight the virus.
Dickinson says part of the reason that this year's vaccine has been so effective is that H1N1 has mutated less quickly than H3N2. The percent of outpatient visits attributed to influenza-like illnesses in the current flu season was 1.13 percent as of January 12.
Dr. Hu says it's impossible to predict what form of the flu will be more prevalent each season.
Seasonal flu signs and symptoms include sudden onset of fever, cough (usually dry), headache, muscle and joint pain, severe malaise (feeling unwell), sore throat and a runny nose.
Because flu viruses are constantly changing, flu vaccines are updated from one season to the next to protect against the most recent and most common circulating flu strains.
Individuals who are very young, very old or pregnant or whose immune systems are compromised are most vulnerable to becoming seriously ill from influenza.
Although this year's flu season is already on the downswing, Skowronski explains that it's not too late for people to get vaccinated.