Nationwide, influenza activity was elevated at the end of February, and the U.S. Centers for Disease Control and Prevention expects the high level of activity to continue beyond the first few weeks of March.
However, in its latest weekly report, the CDC stated, “Severity indicators continue to increase as expected but remain substantially lower than what was observed last season.”
In California, the state’s Department of Public Health reported, “Flu activity is increasing … several more weeks of influenza activity is expected.” Flu-like illness was widespread, as it was in 47 other states. The number of outpatient visits was moderate.
In California, the number of visits to physicians increased during week nine (which ended March 2) compared to week eight. However, it remains below-average nationwide. And compared to the same week in 2018, nationwide visits are lower in 2019.
Hospitalizations increased last week from the previous week.
In Riverside County, visits to physicians surged during week eight (12.4 percent) compared to the prior three weeks and are above the historical average for this date. But the percentage of visits continued to decline in weeks nine and 10. In week nine, they were almost 11 percent and as of Friday, March 9, they were 8.1 percent. However, this is above the historical data for this period.
Local school absenteeism increased to 9.7 percent from 7.4 percent.
Since Sept. 30, 2018, 307 Californians have died from influenza, of which 42 died last week.
CDC expects the flu activity to remain elevated for several weeks. Consequently, health officials still recommend getting a flu vaccine if one has not already gotten it. Even if flu is contracted, the vaccine will mitigate the symptoms.
This year, two different influenza viruses are prevalent. The A(H3) is becoming more common as the flu season progresses. But the A(H1N1) virus still predominates nationally. Both are circulating in California.
The CDC stresses, “The majority of influenza viruses characterized antigenically are similar to the cell-grown reference viruses representing the 2018–2019 Northern Hemisphere influenza vaccine viruses.”
In other words, the viruses now circulating are similar to the viral material that was used to prepare this year’s vaccines.