Unmasking the Mask Makers

Cloth masks, surgical masks, and professional-grade medical masks continue to be essential tools in our fight against COVID-19. Because of this, they continue to be a part of everyday life. When I think of masks it’s usually either in the context of “Did I pack my mask? Phew!” or “How many months before I can cast off this thing”. However, masks are highly functional medical inventions that save lives. Knowing about the scientists who invented, improved, and promoted face masks, helps me remember this. On top of that, these individuals are inspiring! So without further ado, here are three scientists to thank for the face masks that you may be wearing right now.

The Inventor

Paul Berger (1845-1908) was a surgeon at Paris’s Teton hospital and a professor at the nearby Faculté de Médecine.  After reading the research work of the German scientist Carl Flugge documenting the presence of disease-causing bacteria in human saliva, he became concerned that respiratory droplets from his and his assistants were causing post-surgery infections. In response he began wearing a surgical mask of his own invention – six layers of gauze that were sewn to the top of his operation apron and were also tied above his nose during surgeries.

At the time germ theory was gaining popularity and new surgical aseptic techniques were being implemented, so Dr. Berger was unlikely to have been the only surgeon taking such precautions. However, he was the first to take the added step of writing and publishing a paper about the practice (practically titled “On the Use of a Mask in Operating”). When he presented this paper to the Surgical Society of Paris in 1899 his findings and suggestions received a lukewarm to hostile reception. One doctor was reported as saying “I have NEVER worn a mask, and quite certainly I NEVER shall do so”. However, the paper help spread the idea across Europe and a small but growing number of surgeons began copying the practice. One of these practicing surgeons was observed by a young researcher and doctor, Dr. Wu Lein-teh, who powerfully adapted the practice to help fight the Manchurian plague in 1910.

The Developer 

Wu Lien-teh (1879-1960) was born in the region that is now the Malaysian state of Penang but at the time was part of the British Empire. At 17 he won a scholarship to attend the University of Cambridge where he graduated first class in the natural sciences. He went on to study, research, and practice medicine at St. Mary’s Hospital in London, The School of Tropical Medicine in Liverpool, the Pasteur Institute in Paris, and Halle University in Wittenberg. Then, in 1903, he joined the Institute for Medical Research in Kuala Lumpur. However, here he was limited in his studies by a two-tiered colonial system that allowed only British nationals to become medical officers and specialists. In 1904 he returned to Penang and briefly ran a general practice before moving to China to become the vice director of the Army Medical College.

Three years later, at the age of 31, he was assigned to travel to Harbin to investigate a deadly disease that had broken out in the northeastern region of China. Upon his arrival, Dr. Lien-teh conducted a postmortem on one of the early victims. This was the first autopsy ever performed in China and met with resistance as it went against local traditions honoring the dead. However, it also proved pivotal. Dr. Lien-teh found the bacteria Yersinia Pestsi in the victim and correctly determined that the recent wave of deaths had been caused by an outbreak of the plague. He also ascertained that in this case the plague was spreading by air.

In response, he designed and produced surgical masks similar to those he had seen in Europe (but with extra layers of gauze and cotton to better filter incoming air) and instructed his staff and the public to wear them at all possible times. Knowing the gravity of the situation he also petitioned for additional actions: he convinced both the Russian and Japanese railways to cease all train operations (effectively quarantining the region), oversaw the immediate burning of several temporary hospitals and the disinfection of other buildings, and convinced authorities to cremate plague victims rather than waiting for spring burials. Within weeks of implementing these measures, the plague began to decline and within months it had vanished. The deadly disease claimed 60,000 lives but thanks to Wu’s intervention and initiatives it had not spread and was quickly eradicated in the region.  

Dr. Lien-Teh won international acclaim for his handling of the Manchurian plague but did not slow down. He went on to create a public health service in China, fight for Chinese control of port quarantine centers, lead the response to the cholera pandemic of 1920-1921, and was an advocate for both scientific research and social causes especially addressing the growing opium addiction crisis. He continued to also practice general medicine until his death at the age of 80. He was remembered not only for his many career achievements but also for the strong network of friends and colleagues and for his devotion to his family.

The Promoter

Alice Hamilton (1869-1970) was an American physician and researcher, the first women appointed to the faculty of Harvard University, and a “founding mother” of industrial toxicology. She was also an activist and reformer focused on civil liberties, peace, birth control, and protective labor legislation. Her rigorous scientific research in the area of occupational health led to a wide range of reforms that improved worker’s health including the 1970s Congressional Occupational Safety and Health Act.

Dr. Hamilton was born to a tight-knit and established family in Indiana and was homeschooled for most of her early life except for 2 years at a finishing school. However in her twenties, she decided that becoming a doctor would give her both freedom and independence. She entered the University of Michigan’s Medical School where she was one of 14 women in a class of 47 and graduated in 1893. After internships at hospitals in Minneapolis and Boston, she moved to Germany to pursue a growing interest in pathology. Here she was allowed to attend university classes provided that she remained “invisible” to the male students. In 1897 she returned to the US to become a professor of Pathology at the Woman’s Medical School of Northwestern University.

When the medical school closed in 1902 Dr. Hamilton took a position researching tuberculosis, typhoid, and scarlet fever at the Memorial Institute for Infectious Diseases. There she heard a young medical student mention seeing “sprays of spit” coming from surgeons during teaching operations. Dr. Hamilton decided to research the role of “invisible sputum” in cases of scarlet fever and sepsis. Much of the study focused on scarlet fever – proving that streptococci caused the disease, that it was present in the spit of patients, and that it could travel long distances in respiratory droplets. However, another part of the study involved determining the number of bacteria in the saliva of healthy doctors and nurses. She published her findings in the Journal of the American Medical Associations in 1905. The work help convinced contemporaries like George Weaver to institute staff-wide mask mandates in certain hospitals. The paper was also repeatedly cited during the 1918 flu epidemic to help support more general mask mandates.

Dr. Hamilton continued to research and advocate for healthier environments. In particular, her research revealed the health risks of toxic chemicals like lead, carbon monoxide, and benzene that were common in the workplaces of the time. She was also a teacher, a practicing physician, a leader in the women’s rights and peace movements of her time, and a respected medical advisor to the US government. She died at 101.