the white house has requested more than $22 billion for updated vaccines, testing and treatments. and you can see from this map that new cases are trending up in much of the u.s., which means another vaccine dose might be needed. a new study finds that a fourth dose of the moderna or pfizer covid vaccine is safe and provides a substantial immunity boost. dr. erik tobo is a cardiologist and professional with scripps research. he joins me from la jolla in california. thank you, doctor, for all that you do. thank you, rosemary. good to be with you begin. absolutely. so, doctor, the biden administration is issuing a new warning that the u.s. could potentially see 100 million covid-19 infections this fall and winter if congress doesn t approve more money to fight the coronavirus.