evidence: Real-world data show the mRNA vaccines developed by Pfizer/BioNTech and Moderna are 90% effective in preventing COVID-19 infection. Results also suggest just the first dose of the vaccine was 80% effective at doing so 2 weeks after administration. [...] The CDC announces that individuals who are fully vaccinated can travel domestically at low risk to themselves, but should still adhere to COVID-19 precautions such as mask wearing and social distancing. Travel is still not recommended due to rising numbers of cases in the United States. [...] New CDC data show the risk of COVID-19 infection among fully vaccinated individuals is 0.01%. The news comes on the heels of the announcement the United States has fully vaccinated more than half of its adult population. Breakthrough infections can still occur in fully vaccinated individuals, as vaccines are not 100% effective.