Coronavirus SARS-CoV2 Credit: Felipe Esquivel Reed CC BY-SA 4.0

Some diseases seem to come from nowhere and then spread rapidly through populations. These are called epidemics. Pandemics are epidemics that spread across the world. 

  • Print out and cut up the ten cards from each of the three ‘Pandemics and outbreaks’ sheets. You can also do this activity online
  • Place the picture cards in sequence under the headings provided to show how each disease epidemic started and spread. A question mark symbol appears where there is uncertainty
  • The three human figures indicate where the disease crossed over from being an infection of animals to becoming an infection of humans
  • The six cards with text on from the fourth sheet may help you to place the other cards
  • The set of cards for SARS has already been put in sequence. When you have matched all the cards correctly, the small coloured letters in the bottom right-hand corner of each card will line up to spell words
  • If the diseases are ordered as follows: SARS, H1N1 influenza, Smallpox, Bubonic plague, Ebola virus disease, Covid-19, the words will make a sentence.

Now write some text about Covid-19, similar to the other texts on the ‘Pandemics and outbreaks’ sheets. You can build on what you did on Covid-19 in Step 1. 

Display a complete set of the cards, along with any further questions. 

Why have bats spread so many diseases?

You may be wondering why bats are thought to be the cause of so many serious diseases in humans. 

It seems that one of the ways that bats cope with vigorous flying, which can cause tissue damage, is to have a very strong internal system. This seems to give them long lifespans and also protects them against viruses. 

However, to cope with the bat’s strong system, bat viruses also become much more powerful than normal viruses. 

If these viruses spread to other animals and humans, who don’t have as strong systems as bats, they can become deadly. When humans disrupt bat habitats, it appears to stress the bats and makes them shed even more virus in their saliva, which may contaminate fruit, and in droppings that can infect other animals, including farm animals. 

Find out more about bats, including how they benefit humans.