The United States is currently experiencing its most severe flu season in seven years. Since October, there have been over 37 million infections, 480,000 hospitalizations, and 21,000 deaths, as reported by the Centers for Disease Control and Prevention. The CDC also noted that 98 children have succumbed to the flu. In some states, the flu outbreak has been so severe that schools and entire districts have had to shut down. This flu season has also seen the highest rate of doctor visits for flu-like symptoms, including influenza, Covid, and respiratory syncytial virus (RSV), in 15 years. While flu activity has somewhat decreased in recent weeks, experts caution that the season is far from over.
Dr. Susan Donelan, an infectious disease specialist and medical director at Stony Brook Medicine in New York, warned that there may be many more months of illness ahead of us. The exact reasons behind the severity of this year’s flu season remain unclear, although experts suggest several contributing factors. The dominant circulating strains, particularly the H1N1 and H3N2 influenza A viruses, are known to spread rapidly and cause more severe illness. The H3N2 strain, in particular, mutates frequently, making it harder for our bodies to recognize and fight off the virus, even if we have been previously exposed or vaccinated.
Despite concerns about the effectiveness of the flu vaccine against these strains, recent data from the CDC indicates that this season’s vaccine is performing well. Early estimates suggest that vaccinated children and adults have significantly lower hospitalization rates compared to those who are unvaccinated. Dr. Inessa Gendlina, an infectious disease specialist at Montefiore Health System in New York, emphasized that this year’s vaccine offers protection against all three circulating strains.
While vaccines remain a critical tool in preventing severe flu cases, vaccination rates have declined since the onset of the Covid pandemic. This drop in vaccination coverage, especially among children, may be contributing to the severity of this year’s flu season. Experts emphasize the importance of maintaining high vaccination rates to mitigate the impact of influenza outbreaks.
Additionally, experts speculate that accumulated immunity to the flu may have decreased over the years, potentially leaving populations more susceptible to severe infections. As we continue to navigate through this challenging flu season, adhering to preventive measures and vaccination recommendations remains crucial in combating the spread of influenza.
The measures taken to prevent COVID-19 transmission, such as mask-wearing and social distancing, may have inadvertently weakened our immunity to the flu. This could be one of the reasons why influenza is having a significant impact this year, as pointed out by Gendlina. She explained that the consistent use of masks over the past few years has limited the spread of influenza, leading to a decrease in our immunological memory from season to season. This lack of immunological memory may not work in our favor during the current influenza season.
With fewer people wearing masks now, respiratory viruses like the flu have more opportunities to circulate, according to Gendlina. Though flu activity is on the decline, experts caution that the flu season’s end remains uncertain, leaving open the possibility of a resurgence in cases. As a result, there is still ample time to receive a flu shot, advised Donelan.
Recent national wastewater analyses indicate a gradual rise in influenza B concentrations, reported Amanda Bidwell, the scientific program manager at WastewaterSCAN. It is too early to determine if this strain has reached its peak. In light of the potential for a new wave of infections, Gendlina emphasized the importance of getting vaccinated promptly for those who have not done so already.
Even if one has already been affected by the flu this season, it is advisable to get vaccinated if the flu shot has not been received, highlighted Donelan. Given the current circulation of three different flu viruses, there is still a risk of contracting the flu caused by another strain.
Donelan suggested that individuals discuss their personal risk factors for severe infection with their healthcare providers. In certain circumstances, a prescription for the antiviral medication Tamiflu could be obtained in advance to have it readily available if the flu is contracted (Tamiflu must be taken within two days of symptom onset).
Meanwhile, Azarian recommended staying home when feeling unwell, practicing frequent handwashing, and considering the use of masks in crowded or poorly ventilated indoor spaces to safeguard both oneself and others.
