In a recent interview with USA Today, Peter Chin-Hong, MD, a professor of medicine at the University of California-San Francisco and an infectious disease specialist, said that many are quick to downplay the danger of a small get-together because smaller groups of familiar people simply don’t feel as risky. “People don’t think of it in the same way as the Trump rally in Tulsa, a bunch of people on the beach or in the bars, but these small events add up to a lot,” he said. “It’s just invisible.” The warmer summer months have made normal social events such as backyard barbecues, after-work gatherings, and birthday celebrations too irresistible for many across the country. In Connecticut, a spike in cases in late July was tied back to a series of small house parties attended by young people. In June, almost a dozen cases in Pennsylvania were traced to one person who had attended small house parties on the Jersey Shore. And the mayor of a town in New Jersey cited graduation parties as the source of a local spike in cases.ae0fcc31ae342fd3a1346ebb1f342fcb RELATED: For more up-to-date information, sign up for our daily newsletter. Experts says that because of their smaller footprint, such events rarely grab headlines—but just because they’re an invisible source of COVID doesn’t make them any less dangerous. “Small gatherings are a concern because there’s so many of them,” George Rutherford, MD, the principal investigator for California’s contact tracing program, told USA Today. “They may account for a much greater proportion of the cases than we think right now.” On top of many states capping attendance for any gathering at as few as 10 people, some companies are going even further. After a string of recent events that saw abuses of its system, Airbnb amended its rental policy to include a “Global Party Ban” that prohibits social events of any kind at their properties. “We believe having a simpler, global policy will allow us to better support the vast majority of hosts who already ban parties in their homes,” the company said in a press release. The U.S. Centers for Disease Control and Prevention (CDC) says in their guidelines that while intimate get-togethers don’t need to be avoided all together, the risk of holding small gatherings grows with the number of attendees and the “higher the level of community transmission” in the area. Experts also recommend wearing a face mask and moving events outdoors to keep things safe as possible. And for more on how to fight coronavirus, If We All Do This “The Pandemic Would Probably Die Off,” Scientist Says.