The science of how diseases spread
Not all epidemics are created equal. (DepositPhoto/)Scientists, medical professionals, and governments around the world are working to understand how the new respiratory disease ravaging Hubei province spreads—and how bad it could be for the rest of the world. Part of this effort is epidemiology: the study of how infections move through populations and how to control them.Epidemiology incorporates everything from geography to complex mathematics in its effort to understand the spread of disease. Here are some basic epidemiological concepts that can help you get past the panic, misinformation, and xenophobia that tend to drive conversations around a newly emerging illness.Spread it outOne quantity scientists use to measure how a disease spreads through a population is the "basic reproduction number," otherwise known as R0 (pronounced "R naught," or, if you hate pirates, "arr not"). This number tells us how many people, on average, each infected person will in turn infect. While...