A third coronavirus vaccine could be available in the U.S. within the next couple days.The Centers for Disease Control and Prevention voted on Sunday to recommend the use of Johnson and Johnson’s vaccine.The single-dose vaccine that doesn’t require low-temperature transportation and storage could be distributed across Northern California soon.“We just need to get it out to wherever we can get it out to,” said Dr. Vanessa Walker, of Pulmonary Medicine Associates in Roseville.Walker has been working on the front lines of the pandemic in Northern California for almost a year.She said the best vaccine to get is the one available to you.“If you’re in a community that has access to really expensive, low-temperature freezers, that may be where they're giving the Pfizer vaccine,” Walker said. “But if you’re in a place where the only access you have is to a Johnson & Johnson vaccine, it’s still a great vaccine. Get the vaccine.”Gov. Gavin Newsom said California is expected to get about 380,000 doses of the new vaccine this week.Even though the Johnson & Johnson vaccine is less effective at preventing mild illness, Walker said it’s incredibly good at preventing serious illness and death.“It’s 100% effective against hospitalization and death,” she said. “That's the thing we're trying to prevent the most, is keeping our hospitals clear and making sure people don't die.”Even as cases across the state level out and vaccines become more available, Walker said it’s critical people don’t let down their guard to help prevent another surge.“This is the time to really buckle down,” Walker said “Make sure that we're doing all the right things. Wearing your mask, staying safe and get that vaccine as soon as you can.”Johnson & Johnson said it has about 4 million vaccine doses available to ship right now.The company expects to have roughly 20 million ready before April.