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Anna Wessels Williams, Immunologist


René F. Najera, DrPH

October 6, 2021

Over the last few months, we have been using different people from the history of vaccines as our avatars on our social media channels: , , . This month, we are celebrating the life of Anna Wessels Williams, MD, a pioneer in the study of the immune responses to infectious diseases at the turn of the 20th century. :

“Anna Wessels Williams (1863–1954) was already a highly regarded medical and public health researcher at the laboratory of the New York City Department of Health, when she was elected to AAI membership in 1918. Born in Hackensack, New Jersey, into the family of a private-school teacher, Williams is said to have become fascinated by science when she first peered into a school microscope at age 12. After graduating from a local public high school, she enrolled in the New Jersey State Normal School and seemed destined for a career as a school teacher. For the two years following her graduation in 1883, she did, in fact, teach school.

In 1887, however, Williams’s life was to change course. In that year, her sister Millie narrowly escaped death, giving birth to a stillborn child. Struck by the ineffectiveness of the medical treatment received by Millie, Williams became intensely focused on a career in medicine. She resigned from her teaching position to enroll in the Woman’s Medical College of the New York Infirmary later that year.

While still a volunteer, Williams experienced a breakthrough in the search for a higher-yield antitoxin. Working alone in the lab, with Park away on vacation, she isolated and identified a new strain from a mild case of tonsillar diphtheria. The strain, later to be named Park-Williams No. 8 (commonly called Park 8), proved crucial to the development of effective high-yield antitoxin. Within just one year, the antitoxin was in mass production and public health departments were distributing it free of charge to physicians in the United States and Great Britain. Although it was Park who was given the recognition for the discovery of the Park-Williams No. 8 strain, Williams stated that she had no regrets about the presumed credit going to her mentor and collaborator, as she was “happy to have the honor of having my name thus associated with Dr. Park.

In 1895, Williams was hired as a staff member of the laboratory and, in 1896, was able to take a sabbatical to carry out research on an antitoxin for scarlet fever at the Pasteur Institute. In Paris, her work on scarlet fever yielded no dramatic results, but the trip was fruitful in another area of research. Having spent some of her time at the Pasteur involved in its rabies research, she returned to New York intent upon improving rabies prevention and diagnostics. By 1898, she was able to create an effective vaccine that could be mass produced in the United States. This was a major step in the prevention of rabies, but many patients were still succumbing to the disease because of the lengthy, 10-day-or-longer diagnostic period.

Williams turned her attention to a search for some means of detecting the disease much earlier in its occurrence and began studying the brains of infected animals. Her work led to a rabies diagnostic breakthrough within the decade resulting from her discovery of abnormal brain cells in rabid animals. She was not, however, to be generally recognized for this important stride forward, as she was not the first to publish a journal article about the brain cell abnormalities. At the same time that she was performing her research in New York, Adelchi Negri, an Italian pathologist, was studying the same phenomenon in his lab at the University of Pavia. Although it is held that Williams was the first to recognize this distinct brain-cell structure in rabid animals, she is said to have “cautiously waited” to publish her results. Meanwhile, Negri published his seminal paper in 1904 and became widely recognized for the breakthrough. The abnormal cells, known as Negri bodies, bear his name.

Williams continued her rabies research, focusing on the use of brain tissue stains in diagnostics. In 1905, she developed a diagnostic test that yielded results in minutes rather than days. Williams’s test quickly became the standard rabies test and remained so for the next 30 years. It was not to be improved upon until the late 1930s.”



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