Introduction
Fall and winter are coming and so is the Flu season. People might think getting flu shots after receiving COVID-19 jabs is unnecessary, but this is not the case. Anyone, including normal and healthy adults, can experience severe sequelae from the flu. Emerging evidence suggests that co-infection with COVID-19 and influenza viruses can increase severe clinical implications and mortality rates. In contrast, influenza vaccination can reduce the likelihood of hospitalization and shorten hospital stays. Therefore, the public should get vaccinated as soon as possible before the peak flu season, especially the elderly, children and pregnant women. It is recommended that the public be vaccinated with a new season of flu shots in October or November every year to obtain adequate protection before the flu season begins. According to the latest guidelines from the government, members of the public are encouraged to receive the COVID-19 vaccine and seasonal flu vaccine simultaneously (including inactivated influenza vaccines, live attenuated influenza vaccines and recombinant influenza vaccine).
Prevention
The WHO recommends that quadrivalent vaccines for use in the 2023-2024 northern hemisphere influenza season contain the following:
Egg-based vaccines
an A/Victoria/4897/2022 (H1N1)pdm09-like virus;
an A/Darwin/9/2021 (H3N2)-like virus; and
a B/Austria/1359417/2021 (B/Victoria lineage)-like virus; and
a B/Phuket/3073/2013 (B/Yamagata lineage)-like virus.
Cell culture- or recombinant-based vaccines
an A/Wisconsin/67/2022 (H1N1)pdm09-like virus;
an A/Darwin/6/2021 (H3N2)-like virus;
a B/Austria/1359417/2021 (B/Victoria lineage)-like virus; and
a B/Phuket/3073/2013 (B/Yamagata lineage)-like virus.