In Brazil, the Rio Carnival on Feb 5–10 attracts more than 500 000 visitors, and on Aug 5–21 more than 1 million visitors are expected to go to the summer Olympics followed by Paralympic Games on Sep 7–18. Meanwhile, Saudi Arabia expects to host more than 7 million pilgrims from over 180 countries for the Umrah, between June and September, and the Hajj pilgrimage on Sept 8–13.4 and 5 Saudi Arabia receives about 7000 pilgrims from Latin America annually.
The authors exhibit ethos as they show the exact scale of the gathering of people in the coming years. They show that millions of people will be gathering in close proximity in various locations around the world. If the virus infects travelers coming to Brazil for the Rio Carnival or for the summer Olympics then the spread of the virus to the traveler's homeland is likely. This poses big problems for the world as the virus could spread worldwide very easily with the infection of mosquitoes in areas that didn't originally have the virus. An example of this would be if someone from Egypt were to go and be a spectator at the Olympic games and were to get bitten by a mosquito carrying the virus. If the now infected Egyptian were to travel back home and get bit by a domestic Egyptian mosquito then now the mosquito would contract the virus. The mosquito would continue to feed on people all the while spreading the disease to these unsuspecting hosts. All of these newly infected hosts are bitten by different mosquitoes and the trend continues. The mosquitoes also would be reproducing during this time and creating massive amounts of Zika vectors. There is a clear snowball effect here as this new hypothetical area has become a new ground-zero for the virus on another continent.
