For comparison with COVID-19
Influenza makes around 5 million people worldwide seriously ill per year, and causes up to 650,000 deaths from respiratory problems. In the UK, an average 20,000 people per year die as a result or consequence of influenza.
When severe, the respiratory symptoms are similar to COVID-19, with death often due to ARDS (Acute Respiratory Distress Syndrome). Especially vulnerable people include the elderly (>65y), and people with diabetes, ischemic heart disease, hypertension, and immunodeficiency - a similar pattern to COVID-19. However, influenza is also dangerous to under-2s.
Although vaccination is available, this needs to be done every year as the flu virus mutates. In the UK, around 70% of health care workers and elderly people are vaccinated. Overall, the UK has a vaccination rate of 48%.
- The mortality rate of flu is usually 0.1%.
- COVID-19 is currently (April 2020) estimated at between 0.25% and 3%.
- The Spanish flu epidemic of 1918 (where over 50 million died) had a MR of 2.5%.