Novel coronavius appears to spread quicker than flu
The average value of the mortality rate estimates in the previous installment of this review for Covid-19, is 0.4%. This is still four times the same number for flu, but this number is still decreasing and only after widescale testing will the true number be found. It is more likely that the number will end up to be between 0.1% – 0.3%. Below I compare projected Covid-19 deaths with yearly data for the flu for the world and UK.
According to the World Health Organisation, common flu causes up to 5 million cases of severe illnesses every year and 290,000 to 646,000 deaths, and this is despite a vaccine being readily available for many people. If the current rate continues, Covid-19 could be attributed to 681,000 deaths worldwide.
Figure 5. Projected worldwide fatalities attributed to Covid-19 using the assumption that monthly fatality rate for the first four months of 2020 is upheld for the whole year. This is compared to the yearly figures for Influenza (Flu) which were displayed in Part 1 of the review.
The official UK Government statistics show Influenza kills an average of 17,000 people per year. In the winter of 2018-2019 it was 1,692 and in 2014-2015 it was 28,330. Using this average, in the last 15 years, the UK will have seen over 200,000 deaths attributed to it, again despite 25 million being offered a vaccine every flu season. A vaccine for coronavirus is not available yet.
Even though this graphic looks ominous compared to flu, there is still a large amount of uncertainty surrounding how many people have actually caught the virus. If the reports are right and a considerably higher number of people have been infected than thought, then this projection may be a ‘worst case scenario’ figure. It is also unknown how the summer months will affect it, conditions which normally slow the spread of those such as the flu, resulting in terms like ‘flu season’ which is during the colder months.
Figure 6. Projected UK fatalities attributed to Covid-19 using the assumption that monthly fatality rate for the first four months of 2020 is upheld for the whole year. This is compared to the yearly figures for Influenza (Flu) which were talked about in Part 1 of the review.
One of the biggest sources of confusion and panic is the difference between the danger a virus poses, such as this novel coronavirus, and the rate it spreads. By saying it is highly contagious does not mean it is more likely to cause you harm, nor is it necessarily surprising information in our current situation. A person with the flu is thought to infect an average of around 1.28 other people, but this number is thought to be 2-3 for novel coronavirus. Part of the reason for this could be that it is a more contagious virus that has worked out a way to become transmitted amongst humans faster, but part of the difference will be because it is new, or ‘novel’. Our bodies have not built up immunity to it, nor has a vaccine been found, meaning that it can spread rapidly between us. Therefore, as hospital admissions could be bunched closer together, it could explain some of the panic as health systems are placed under more stress. However, it still remains to be seen whether it is more fatal than flu.
What do you think? Read the next installment in the Covid-19 Review here! It investigates how age affects the severity of Covid-19.