Last week, the flu reached epidemic portions. That means 6.8 percent of all deaths were flu-related. While the numbers have slightly decreased the first week of January, influenza is still considered to be widespread. 43 states are currently experiencing ‘high’ flu activity.

The final week of December saw 12.6 per 100,000 people hospitalized for the flu. During the same week last, the number of hospitalizations was only 8.9 per 100,000.

What happened? The type of influenza virus that is predominant this season causes the difference. Last year, the H1N1 virus was most prevalent. This year, the H3N2 virus has accounted for 95 percent of all flu illnesses reported in the US. The H3N2 variation is known to cause more severe illness and is associated with a higher mortality rate. The last time H3N2 was predominant, during the 2012-2013 season, the hospitalization rate was 13.3 per 100,000 people for the last week of December.

This is especially true for older people and young children. In this week alone, there have been six flu-related pediatric deaths. The total number of pediatric deaths this season is already 21. The deaths occurred in the following states: Arizona (1), Colorado (1), Florida (2), Kansas (1), Minnesota (3), North Carolina (2), Nevada (1), Ohio (2), Tennessee (3), Texas (3), and Virginia (2).

The major circulating H3N2 virus is said to have ‘drifted’ meaning that it no longer matches the vaccine. This suggests that the vaccine’s effectiveness at preventing the flu is greatly reduced. Nonetheless, the CDC still advises people to get the flu shot, particularly those at high-risk of serious flu complications.

The CDC also offers a number of other recommendations on how to stay healthy this year:

Do your best to avoid contact with sick people.

If you are sick, remain home for 24 hours after the fever breaks unless you are seeking medical care.

Whenever you cough or sneeze, cover your nose and mouth with a tissue. Be sure to immediately throw out the tissue.

Wash your hands frequently with warm soapy water.

Avoid touching your nose, mouth or eyes.

Disinfect surfaces that maybe contaminated with the flu virus.