SAN FRANCISCO -- In an effort to curb the spread of novel coronavirus, governments are turning to shelter in place and stay at home policies.
"Shelter in place" means you need to stay home and only leave your home for essential errands like doctor appointments, getting food from the grocery store, or walking the dog.
"This is an aggressive measure, but we need to take a very radical step in this way to limit the spread," said ABC 7 News medical expert, Dr. Alok Patel.
RELATED: Video of empty San Francisco streets after coronavirus shelter-in-place order
The coronavirus is transmitted by droplets from coughs and sneezes. The best way to prevent getting it -is by practicing social distancing.
Just one person can be responsible for infecting multiple people.
"Remember, a rough estimate is that one person with this coronavirus can spread it to two people," Patel said. "And then those two will spread it to four and so forth. So if we don't follow these rules, we could really see it spike and get an exponential growth, that's what we are trying to avoid."
If too many people get sick too fast, hospitals would be overwhelmed with infected people. Shelter in place measures help keep hospitals from being overwhelmed.
RELATED: Quarantined family shares daily updates about what it's like to be tested, isolated due to COVID-19 fears
If we can we cut-off an infected person from the larger population and keep 6 to 10 feet apart, Infections still occur, but the number of people infected slows down, and hospital have an opportunity to treat the sickest people.
The big challenge is keeping those people sheltered. Not everyone who gets the coronavirus exhibits symptoms, and though they may feel like healthy, they aren't. Ignoring the effort to keep the coronavirus from spreading will reintroduce the virus to the sheltered population.
"You really, really, need to stay indoors, unless you are traveling out doors for an essential reason," said Dr. Patel. Doctor's orders to keep us all healthy.
Coronavirus: Here's how shelter in place, stay at home orders can slow spread of COVID-19