Washington, Dec 22 : Amid rising cases of the highly transmissible Omicron variant of Covid, US President Joe Biden has announced 500 million free at-home test kits, even as he urged people to get vaccinated as well as take a booster shot. The at-home tests will be available for purchase online as well as at the local pharmacy from January, which will be "reimbursed". "Because Omicron spreads easily, especially among the unvaccinated, it's critically important that we know who's infected. That means we need more testing," Biden said at the White House on Tuesday during a speech outlining the new coronavirus-response measures. "The federal government will purchase one half billion... additional at-home rapid tests, with deliveries starting in January. We'll be getting these tests to Americans for free. And we'll have websites where you can get them delivered to your home," Biden said. The free testing will help reduce the waiting lines, as well as reduce the burden of healthcare systems. The President also noted about over 20,000 free testing sites in the country. In addition, 1,000 military doctors, nurses, and medics will be deployed to help staff local hospitals and expand capacity, Biden said. Omicron, first detected from southern Africa in late November, has so far spread to 106 countries, and has become the dominant strain in both the US and the UK, among other countries, outpacing the previously dominant Delta variant. The US has reported one death due to Omicron to date, while the UK has 12. People who remain unvaccinated are the reason behind its fast spread, Biden said. Besides being at serious risk of getting infected and dying, they are also likely to overwhelm an already burdened healthcare system, the President said. "Please get vaccinated. It's the only responsible thing to do. And those who are not vaccinated are causing hospitals to overrun - become overrun again. "Omicron is serious, potentially deadly business for unvaccinated people. If you are not fully vaccinated, you have good reason to be concerned. You're at a high risk of getting sick. And if you get sick, you're likely to spread it to others, including friends and family. And the unvaccinated have a significantly higher risk of ending up in a hospital or even dying," he noted. Biden also urged those vaccinated to get booster shots, adding that it will protect against the vaccine evading the Omicron variant. "Our doctors have made it clear: Booster shots provide the strongest of protections. People with booster shots are highly protected.A Join them.A Join us. If you're fully vaccinated, and especially if you got your booster shot, you are highly protected," he said. At the same time to prevent hospitals from being "extremely stressed" due to unvaccinated adults, Biden said his administration is "preparing hospitals". "We are preparing hospitals for what's coming. Those 40 (million) unvaccinated adults have a good chance of getting Covid-19, and some of you will get very sick. That will mean hospitals are going to get extremely stressed -- extremely stressed again, both in terms of equipment as well as personnel to care for those who get sick. "That's why my administration has stockpiled and pre-positioned millions of gowns, gloves, masks, and ventilators. We used to call it PPP (PPE). We're ready to send them immediately to any state that needs more." The US continues to be the worst-hit country with the world's highest number of cases and deaths at 51,272,854 and 810,045, according to Johns Hopkins University. So far more than 200 million Americans have been fully vaccinated, while more than 60 million Americans have taken booster shots. /IANS