His Facebook post on Friday shows a photo of Zuckerberg holding his daughter, Max, alongside the caption "Doctor's visit - time for vaccines!" Zuckerberg and his wife, Priscilla Chan, announced the birth of their child on December 1.
By Monday, the image had generated more than 3 million likes and 69,000 comments, with many presuming the post was an implicit endorsement of child vaccinations.
The decision to vaccinate children has become a heated debate in the US over the past several years. Anti-vaccination advocates claim that inoculating children can cause diseases or developmental disorders, like autism.
"I love that you are promoting vaccines!" wrote Raluca Sander on Friday. "There is so much confusion on that topic out there and it causes too much harm."
"Thank you, Mark Zuckerberg for not only creating this social media platform so that I may advocate for vaccines, but thank you for being a public health advocate yourself!" wrote Angela Quinn.
Other Facebook users, however, slammed Zuckerberg, claiming that vaccinations are dangerous.
"Poor baby," wrote Steve Schneider on Friday. "Forget those natural immunities we got the good stuff right here in this syringe."
"Pharmaceutical companies make HUGE profits off of a sick society," Ian Humphries wrote on Friday. "Use your head people."
Zuckerberg, followed by more than 48 million on his social media platform, sparked an outcry in February of last year after endorsing the non-fiction book "On Immunity," which explores the vaccination debate in America.
"Vaccination is an important and timely topic," Zuckerberg wrote in a Feb. 18 post. "The science is completely clear: vaccinations work and are important for the health of everyone in our community."
© Thomson Reuters 2016
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