If the virus begins to infect 1000s of people, it will mutate. For better or worse. A less deadly strain may actually make things worse overall. People will continue about their business even if they don't feel well -- infecting dozens. When the virus kills people within hours, the infected don't have the time or energy to spread it far. So imagine the death rate falls to 30% but the infection rate rises to 10 per 10,000 people. And at some point society would start breaking down. Violence and mayhem would cause new big problems. Yep, see if these numbers track for the next month. Watch Lagos. And pray.