The 2018 flu season appears to have hit a plateau after a particularly virulent season. According to the Arizona Department of Health report, there have been over 22,917 reported cases of flu in the state and 461 pneumonia and influenza deaths.
This represents a represent a small proportion of the true number of cases of influenza as many people with the flu did not visit the doctor. The 22,917 Arizona cases came only from reports to ADHS by laboratories.
Week 6 of the influenza season ended February 10, with 968 laboratory confirmed cases of flu — over 100 more cases compared to the same week last season. There have been a total of over 19,500 more cases of flu to date this season compared to last season.
One problem is that the flu vaccine did not protect against the A virus H3N2 which caused the lion’s share of the illness in most parts of the country this year. There are two main types of influenza – Type A and Type B. Influenza A viruses can be further divided into subtypes such as A (H1), or A (H3). According to the Centers for Disease Control, three-quarters of people who got a flu shot this year were not protected against the H3N2 strain.
Even if the season appears to have peaked, flu viruses will circulate for weeks to come and people should continue to take precautions against getting infected. Flu is spread by droplets that can linger on surfaces such as countertops, which is why hand-washing is so important. It also spreads via sneezing and coughing and, perhaps, may float in the air on tiny droplets emitted by simple breathing.
