Anti-vaccination proponents are up in arms today and a significant number of them are taking to Facebook to blast Mark Zuckerberg for taking his six-week old baby to the doctor to get the vaccines, according to a report on slate.com.

The Facebook founder posted a photo of him and his daughter, Max, with the caption, “Doctor’s visit-time for vaccines!”, and many say he is sending a message about his beliefs that vaccinations are necessary for children.

Almost immediately, anti-vaccination advocates began to criticize the entrepreneur for placing his child at risk for conditions some believe are caused by vaccinations, but many also were praising him and making positive comments about the move.

Many commenters simply said they hoped the Zuckerberg family had done their homework before deciding whether or not to vaccinate.

Zuckerberg had previously said he was a supporter of doctor-recommended vaccinations.  Last February, he chose the book “On Immunity” for his 2015 book club, posting on Facebook “Vaccination is an important and timely topic. The science is completely clear: vaccinations work and are important for the health of everyone in our community.”

He added, “this book explores the reasons why some people question vaccines, and then logically explains why the doubts are unfounded and vaccines are in fact effective and safe.”

There has been a national debate raging about the pros and cons of vaccinations, highlighted by a measles outbreak and Disneyland in 2014.  The state of California, where Zuckerberg currently lives, has a requirement for almost all children to be fully vaccinated before they are allowed to attend a public or private school.

Zuckerberg and wife, Priscilla Chan, welcomed their first child in November of last year, and the CEO has taken a very active role in the care of the child while he is taking a two-month paternity leave from the company.