No mate, not a shred.
"In general, active room ventilation and the ubiquitous wearing of face masks (i.e., by all subjects) may reduce the individual infection risk by a factor of five to ten, similar to high-volume, high-efficiency particulate air (HEPA) filtering."
https://www.scopus.com/record/display.uri?eid=2-s2.0-85095590849&origin=resultslist&sort=cp-f&src=s&st1=Face mask viral load&st2=&sid=9919895baa393f4078312fc1d29d46a6&sot=b&sdt=b&sl=35&s=TITLE-ABS-KEY(Face mask viral load)&relpos=9&citeCnt=0&searchTerm=
DOI: 10.3390/ijerph17218114
" A mask documented to be loosely fitting by a PortaCount fit tester, to simulate how masks are worn by healthcare workers, blocked entry of 68.5% of total virus and 56.6% of infectious virus"
https://www.scopus.com/record/display.uri?eid=2-s2.0-84861038567&origin=resultslist&sort=cp-f&src=s&st1=Face mask viral load&st2=&sid=9919895baa393f4078312fc1d29d46a6&sot=b&sdt=b&sl=35&s=TITLE-ABS-KEY(Face mask viral load)&relpos=0&citeCnt=68&searchTerm=
DOI: 10.1093/cid/cis237
"N95 mask was more effective than surgical mask in preventing expelled air leakage during patient's coughing but there was still significant sideway leakage to 15 cm." (Note - this is keeping doctors safe during aerosol generating procedures at a range of 15cm. Compare that to walking about at 2m...)
https://www.scopus.com/record/display.uri?eid=2-s2.0-84891144308&origin=resultslist&sort=cp-f&src=s&st1=Face mask viral load&st2=&sid=9919895baa393f4078312fc1d29d46a6&sot=b&sdt=b&sl=35&s=TITLE-ABS-KEY(Face mask viral load)&relpos=2&citeCnt=31&searchTerm=
DOI: 10.3978/j.issn.2072-1439.2013.06.18
"Due to uncertainty of the main transmission routes, the infection control policies faced with more challenges. The possible main route of transmission is thought to be the close contact and respiratory droplets. Therefore, it is necessary to maintain physical distance and using the facemask"
https://www.scopus.com/record/display.uri?eid=2-s2.0-85094564584&origin=resultslist&sort=cp-f&src=s&st1=Face mask viral load&st2=&sid=9919895baa393f4078312fc1d29d46a6&sot=b&sdt=b&sl=35&s=TITLE-ABS-KEY(Face mask viral load)&relpos=10&citeCnt=0&searchTerm=
DOI: 10.1016/j.nmni.2020.100778
"The method used in this study was to measure the change in relative humidity when wearing a mask, compared to no mask, in various scenarios, based on the assumption that as the virus is air-borne the smaller the increase in humidity the less the spread of the virus. The results above show that the use of a mask, excluding some simple home-made ones, significantly reduces the spread of humidity."
https://www.scopus.com/record/display.uri?eid=2-s2.0-85088657418&origin=resultslist&sort=cp-f&src=s&st1=Face mask viral load&st2=&sid=9919895baa393f4078312fc1d29d46a6&sot=b&sdt=b&sl=35&s=TITLE-ABS-KEY(Face mask viral load)&relpos=13&citeCnt=0&searchTerm=
DOI: 10.1080/03091902.2020.1797198
"this review revealed that thorough hand washing with antiseptic soap and running water and usage of alcohol hand sanitizer, frequent surfaces cleaning, strict adherence to social distancing, regular respiratory hygiene, wearing of protective face masks, frequent testing, self-isolation, quarantine and rigorous contact tracing will help to prevent further spread, and control the transmission of the viral pathogen."
https://www.scopus.com/record/display.uri?eid=2-s2.0-85090926887&origin=resultslist&sort=cp-f&src=s&st1=Face mask viral load&st2=&sid=9919895baa393f4078312fc1d29d46a6&sot=b&sdt=b&sl=35&s=TITLE-ABS-KEY(Face mask viral load)&relpos=16&citeCnt=0&searchTerm=
DOI: 10.18683/germs.2020.1208
"The use of face masks in public ... presumptively decreases the viralload and contributes to a favourable clinical outcome in COVID-19 disease."
https://www.scopus.com/record/display.uri?eid=2-s2.0-85087321091&origin=resultslist&sort=cp-f&src=s&st1=Face mask viral load&st2=&sid=9919895baa393f4078312fc1d29d46a6&sot=b&sdt=b&sl=35&s=TITLE-ABS-KEY(Face mask viral load)&relpos=18&citeCnt=0&searchTerm=
DOI: 10.21101/cejph.a6290
"Some international studies have also demonstrated the efficacy of surgical masks in preventing respiratory virus transmission. For example, in 2008, a randomised, controlled clinical trial study from Australia showed that surgical masks had efficacious protective efficacy of over 80% against the transmission of respiratory viruses.
6 In 2011, Jefferson et al
7 found that wearing a mask or N95 respirator might reduce respiratory virus infection. More recently, researchers from South Korea studied four patients infected with COVID-19 and found that surgical masks helped prevent the spread of severe acute respiratory syndrome coronavirus 2 and reduced the viral load of a cough.
8"
https://www.hkmj.org/abstracts/v26n3/267.htm
DOI: 10.12809/hkmj208566
Not a shred. No evidence at all, particularly when compared to the magnificent scientific brains of Eric Clapton and Van Morrison.