Blog #2

Influenza is a viral disease that can cause mild or severe symptoms. Some symptoms include fever, cough, sore throat, body aching, and runny nose. The influenza is caused by a single-stranded, segmented RNA virus. Because it is a segmented virus, it is capable of changing with every replication through antigenic drift. Mutations of the virus’s genes can lead to changes in the NA and HA surface proteins of the virus. These continuous mutations over time lead to antigenic drift of the virus, and the body can not recognize the proteins of the new virus. For this reason, a new vaccine is created and adjusted every year in order to grant immunity towards the evolved version of the influenza virus based on the changes that occurred during the previous season.

According to this article, the 2019-2020 influenza season is expected to be the worst since 2017-2018, the deadliest influenza season in the decade. The December graph uploaded by the CDC shows that the influenza death rate in 2019 is similar to that of the 2017 influenza season. The severity of this season can be seen in this article which reported that the Influenza Like Illness activity was reportedly high in 45 states out of the 50 states in the United States during the first week of February. The majority of the influenza-involved hospitalizations were in connection with the influenza A virus, at 62.2% of hospitalizations. More recent reports show that the cumulative hospitalization rate this season is similar to that of other seasons, the rates of children and young adults are higher than usual.

Vaccine effectiveness normally ranges between 40% to 60%, but is is currently too early in the season to make an estimation about the effectiveness of this year’s vaccine. There are several options for vaccines this year, however, all regular-dose flu shots will be quadrivalent. In addition, the CDC and ACIP are now telling people that vaccinating before July and August can reduce the effectiveness of vaccines during the flu season, and they are suggesting to get vaccinated in late-October. Vaccination is important for everyone, but it is even more crucial for susceptible suspects such as those under 2 years old and those older than 65 years old. No matter the effectiveness of this year’s vaccine, it is important to get vaccinated because some protection can still be provided from the antibodies created by the body when vaccinated; some protection is better than no protection. Although some argue that they still get infected with influenza despite receiving the vaccine, the vaccine can be the difference between mild and severe symptoms or severe symptoms and death.