At home and abroad, Salma Hayek strongly supports vaccination and is an activist for tetanus elimination, according to UNICEF. Regarding her motivation, Hayek told the spokespeople at UNICEF, "the thought of losing a child to a disease which can be easily prevented seems unbearable, especially when it is within our power to prevent it."

Kristen Bell has always been very open and honest about parenthood, and it's no different on the topic of vaccines, according to Today. "It's a very simple logic: I believe in trusting doctors,"Bell said. In particular, Kristen Bell is pro-vaccine especially when it comes to pertussis and she added,"when Lincoln was born, we simply said, 'you have to get a whooping cough vaccination if you are going to hold our baby.'"

Mixing humor with hard-hitting facts is definitely in the wheelhouse of Last Week Tonight host, John Oliver, a vaccine advocate. Oliver has become well known for pulling back the curtain on scams and corruption and "big pharma" is no exception since he has consistently debunked autism myths surrounding vaccination.

According to The Los Angeles Times, Kim Kardashian was firm about being pro-vaccine when she had family members get the tetanus, diphtheria, and pertussis vaccinations before holding baby, North West.

In an interview with ABC News, Jennifer Garner advocated for vaccination and flu shots, saying, "I want to help make sure that all moms across the country understand that influenza is serious and that vaccination should be a family priority."

Primarily known for being a magnate in the world of technology, Bill Gates is also a pro-vaccine activist. Bill and Melinda Gates actually pledged $10 billion to what their foundation has called, "the decade of vaccines." According to their foundation's site, Melinda Gates said, "we’ve made vaccines our number-one priority at the Gates Foundation because we’ve seen firsthand their incredible impact on children’s lives."

Like many other celebrity moms, Sarah Michelle Gellar is a pro-vaccine activist, especially for pertussis. Gellar told Parade, "the best way to prevent [pertussis] is to vaccinate yourself and your children against it.

After having her twins, Jennifer Lopez, who is pro-vaccine, became spokesperson for The Sounds of Pertussis in conjunction with The March of Dimes, according to United Press International. "This issue is important to me," she said. "I didn't know too much about it before becoming a parent but whooping cough is on the rise."

Though many know her for an amazing figure skating career, Kristi Yamaguchi is also pro-vaccine and aims to raise awareness about influenza prevention. According to Dallas' KTTC News Center, Yamaguchi said, "I take my daughters to get vaccinated every year and ask everyone in contact with them to make sure they are vaccinated as well, to help create a cocoon of protection."

According to the White House official site, both Michelle and Barack Obama are pro-vaccine. "We wanted to make sure nationwide that children were getting [H1N1 vaccinations] it is so important and, frankly, the African American vaccination rate has been substantially lower than the general population."

Though she has gained some haters for her outspoken approach, Amanda Peet supports vaccines, as she told Us Weekly, "I think I'm just a concerned mom, and now that I have a newborn who's too young to be vaccinated, it really hits home for me."

Since Jennifer Lopez hasn't been shy about being pro-vaccine, it's no surprise that the father of her children shares the same viewpoint. In a PSA for the United States Department of Health and Human Services, Marc Anthony advocated for vaccines, specifically for H1N1.

She doesn't just play a concerned mother on television's Modern Family, in real life, Julie Bowen is a pro-vaccine activist and supports flu shots, according to ABC News. In addition to her three sons, Bowen said she, her husband, babysitter, and other relatives all got flu shots to protect her family's health.

In an interview with People, Marissa Jaret Winokur revealed why she is pro-vaccine, saying, "there is an HPV test that might have caught my precancerous cells earlier." Clearly this particular disease and vaccination has personal meaning and she's open about her position on the topic. "There's a vaccine, it makes sense to take these precautions," she explained to People. "I'll encourage my friends' teenage daughters to get vaccinated."

After becoming a parent, Keri Russell also became pro-vaccine, according to Parents of Kids with Infectious Diseases (PKIDs)."Pertussis is a vaccine-preventable disease," she told the organization's official site. "I'm partnering with PKIDs to raise awareness about the importance of booster shots for new parents and people who come in close contact with infants."