ERIKA: SOME SCIENTISTS NOW BELIEVE THE PRECAUTIONS WE TOOK DURING THE PANDEMIC ARE CONTRIBUTING TO AN EARLY SURGE IN VIRUSES THIS FALL. HERE TO EXPLAIN IS DR. PAUL SAX, CLINICAL DIRECTOR OF INFECTIOUS DISEASES AT BRIGHAM AND WOMEN'S HOSPITAL. BEN: AS YOU KNOW, HEALTH OFFICIALS RECOMMENDED FACE MASKS, SOCIAL DISTANCING, EVEN LOCKDOWNS, TO SLOW THE SPREAD OF COVID. BUT IT ALSO SLOWED THE SPREAD OF OTHER VIRUSES. WE HAD NO FLU IN TWO YEARS. DO YOU THINK THAT'S WHY WE'RE SEEING SO MANY CASES RIGHT NOW? >> STRIKING THING IS CASES ARE BACK TO NORMAL. WHAT'S SO ALARMING ABOUT IT IS THAT WE NOW HAVE FLU. WE HAVE RSV AND COVID-19. ALL THREE TOGETHER, WHICH MEANS THAT WE ARE SEEING LOT OF PEOPLE WITH RESPIRATORY VIRUSES OF VARIOUS TYPES. ERIKA: SOME EXPERTS ARE WARNING ABOUT A TRI-DEMIC OF RSV, THE FLU AND COVID. ARE YOU SEEING ANY SIGNS OF THAT HAPPENING HERE YET? >> WOULD WE'RE SEEING IN THE ENTIRE UNITED STATES IS AN INCREASE IN ALL THREE RESPIRATORY VIRUSES. I THINK WE CAN EXPECT THAT. WE HAVE TO BE PREPARED THAT THE SEASON, COMES, THERE ILL BE MORE RESPIRATORY VIRAL INFECTIONS. THAT'S TRUE EVERY YEAR. ONLY YEAR EXCEPTION YEARS OF PANDEMIC, ONLY VIRUS WE SAW WAS COVID-19 BECAUSE IT'S SO CONTAGIOUS. THING TO REMEMBER IS THAT FIRST OF ALL, THERE'S A FLU VACCINE. IT IS PARTIALLY EFFECTIVE. I HIGHLY RECOMMEND PEOPLE GET IT. FOR RSV, THE VULNERABLE POPULATIONS ARE OLDER ADULTS, PARTICULAR PEOPLE OVER 65. BEN: LET'S TALK ABOUT RSV. WE KNOW ABOUT THE THREAT FOR YOUNGER CHILDREN, ESPECIALLY TODDLERS AND INFANTS. BUT THE CDC SAYS THE VIRUS ALSO CAN BE FATAL FOR OLDER ADULTS. WHAT CAN YOU TELL US ABOUT THE RISK FOR THEM RIGHT NOW? >> THE FIRST THING TO REALIZE IS THAT MOST EVEN OLDER ADULTS WHO GET RSV, THEY FEEL LIKE IT'S A COLD. IT'S THE MINORITY WHO GET VERY SICK. WHEN YOU DO GET SICK WITH RSV IT CAN CAUSE A BAD PNEUMONIA. THE KEY FOR HERE IS PREVENTION. THE WAY THAT WE BELIEVE MOST VIRUSES ARE SPREAD, PREDOMINANTLY BY THE RESPIRATORY IF YOU'RE A CROWDED SETTING, MASKING STILL MAKES SENSE FOR PEOPLE AT RISK. THAT COUNTS FOR LOT OF THE CASES. ALSO, THE GOOD NEWS IS WE JUST HEARD SOME INFORMATION ABOUT AN EXPERIMENTAL RSV VACCINE THAT LOOKS PROMISING. THERE'S TWO VACCINES IN THE WORKS. FAIRLY SOON, WE HAVE AN RSV VACCINE TO OFFER TO OUR VULNERABLE PATIENTS. ERIKA: THANK YOU SO MUCH FOR JOINING US.