PROOF THAT VACCINES DO WORK. JUST AS THE VACCINE AGAINST SMALL-POX WORKED TO OBLITERATE IT FROM OFF THE EARTH.
Samuel L. Katz, doctor who helped develop measles vaccine, dies at 95
As the polio wave eased, Dr. Katz arranged a meeting with John Enders, who shared the 1954 Nobel Prize in Medicine for work isolating strains of the polio virus. For Dr. Katz, it would begin more than a decade of collaboration as a key member of a team that developed a vaccine for measles, a highly contagious virus once common among children that had been blamed for up to 2.6 million deaths a year around the world, including hundreds in the United States.
“I came along at the right time, in the right laboratory, with the right colleagues,” said Dr. Katz, who died Oct. 31 at 95 at his home in Chapel Hill, N.C.
The vaccine was one of the landmark discoveries in childhood medicine during decades that also tamed chronic threats such as polio, rubella and mumps. Dr. Katz then went on to a prominent career in virology and pediatrics that spanned health crises such as AIDS and the covid pandemic and the rise of anti-vaccine movements.
“People have lost sight of what it is they are being protected from,” said Dr. Katz, who was emeritus professor at Duke University after more than two decades as head of its medical school’s pediatrics department.
The World Health Organization estimated the measles vaccine saved an estimated 17.1 million lives between 2000 and 2015 alone. (The WHOreported more than 17,000 measles cases worldwide in January and February this year, compared to 9,665 during the first two months of last year. The Centers for Disease Control noted 33 measles cases in the United States so far this year.)
When Dr. Katz arrived at Enders’s lab in Boston, the measles virus had already been isolated from a local schoolboy, David Edmonston. The challenge was to find a way to make an “attenuated,” or weakened, virus that could be the foundation for a vaccine.
“And indeed we went to embryonated hens’ eggs,” Dr. Katz said in a 2014 interview for the podcast “Open Forum Infectious Diseases.”
The “Edmonston virus” was passed through chick embryos more than a dozen times, reducing its strength. It was then injected in monkeys by the Enders-led team, which included a research fellow from Yugoslavia, Milan Milovanovic. The monkeys developed none of the classic symptoms such as fever and rashes or showed viremia, the presence of the virus in the bloodstream. But the monkeys had antibodies.
“So we were on our way,” said Dr. Katz.
The human trials underscored some of the ethical questions during an era of less-regulated vaccine research, such as flu vaccine tests in the 1940s on children at a Pennsylvania mental-care institution and Albert Sabin using federal prisoners in Chillicothe, Ohio, in late-stage polio vaccine studies in 1954 and 1955.
The Enders team used the Walter E. Fernald State School in Waltham, Mass., a facility for children with severe neurological disorders. Dr. Katz said about 20 patients were picked and parental consent was given.
“We injected these youngsters with the chick cell virus and observed them daily,” Dr. Katz said in the podcast. “We did throat cultures. We did blood cultures. And they never had any viremia, they never had any virus in their throat. … So we had made the big jump.”
The findings were published in 1961 in the New England Journal. Inquires started to flood in.
Those included letters and telegrams from a British pediatrician, David Morely, in Nigeria. He appealed to expand the measles vaccine tests to Nigeria, where the mortality rate for the illness was as high as 15 percent.
The work by Dr. Katz in Nigeria produced important insights for global vaccination efforts, including how infants with measles often stopped breastfeeding because of mouth sores and became severely dehydrated. Simple hydration treatments were added to measles vaccine regimes in Nigeria and elsewhere.
“It is true that despite all that vaccines have done to improve the health of individuals and communities in the United States and throughout the world, they are not perfect,” he added. “However, one simple fact cannot reasonably be disputed — the benefits of immunizations far outweigh any possible risks.”
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