Here's how you could catch COVID-19. The novel coronavirus that causes the disease COVID-19 has spread from the site of the original outbreak in China to affect 75 countries around the world. If effective controls aren't put into place, COIVID-19 could ultimately infect between 40% and 70% of the population worldwide in the coming year, according to Harvard T.H. Chan School of Public Health epidemiologist Marc Lipsitch. Most of those cases would be mild, and some people might show no symptoms at all. But the prospect of being infected with a new virus can be frightening. The symptoms to look out for, according to the Centers for Disease Control and Prevention (CDC), are fever, coughing and shortness of breath. These symptoms usually appear between two days and two weeks of exposure to the virus. According to a report in the Journal of the American Medical Association, as many as 98% of COVID-19 patients have a fever, between 76% and 82% have a dry cough, and 11% to 44% report exhaustion and fatigue. The disease appears to become more severe with age, with the 30- to 79-year-old age range predominating the detected cases in Wuhan, where the outbreak began, according to a study in JAMA. Children seem to be at less risk of suffering noticeable symptoms of the disease. In more serious cases of COVID-19, patients experience pneumonia, which means their lungs begin to fill with pockets of pus or fluid. This leads to intense shortness of breath and painful coughing. Currently, testing for the virus that causes COVID-19 in the United States is limited to people with severe symptoms, according to Paul Biddinger, the director of the emergency preparedness research, evaluation and practice program at the Harvard T.H. Chan School of Public Health, who spoke in a university webcast March 2. This means that it isn't appropriate to be tested at the first sign of a fever or sniffle. Seeking medical care for mild illness can also potentially transmit that illness, or lead to catching new illnesses in the hospital or clinic, Biddinger added. If you become ill with these symptoms and live in or have traveled to an area where COVID-19 is spreading, which now includes parts of the U.S., the CDC recommends calling your doctor first rather than traveling to a clinic. Physicians work with state health departments and the CDC to determine who should be tested for the new virus. However, the CDC also recommends that people with COVI-19 or any respiratory illness monitor their symptoms carefully. Worsening shortness of breath is reason to seek medical care, particularly for older individuals or people with underlying health conditions. The CDC information page has more information on what to do if you are sick. Coronavirus basics The novel coronavirus, now called SARS-CoV-2, causes the disease COVID-19. The virus was first identified in Wuhan, China, on Dec. 31, 2019. Since then, it has spread to every continent except Antarctica. The death rate appears to be higher than that of the seasonal flu, but it also varies by location as well as a person's age, underlying health conditions, among other factors. For instance, in Hubei Province, the epicenter of the outbreak, the death rate reached 2.9%, whereas it was just 0.4% in other provinces in China, according to a study published Feb. 18 in the China CDC Weekly. Scientists aren't certain where the virus originated, though they know that coronaviruses (which also include SARS and MERS) are passed between animals and humans. Research comparing the genetic sequence of SARS-CoV-2 with a viral database suggests it originated in bats. Since no bats were sold at the seafood market in Wuhan at the disease’s epicenter, researchers suggest an intermediate animal, possibly the pangolin (an endangered mammal) is responsible for the transmission to humans. There are currently no treatments for the disease, but labs are working on various types of treatments, including a vaccine. Source