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Do vaccines really work?

Is it true that these days, most people who come down with a disease for which there's a vaccine (such as measles) have been vaccinated against it?

Paul Offit

infectious disease expert

It is true, but that doesn't mean vaccines don't work. It just means they're not perfect. In the rare case of an outbreak, a certain number of vaccinated people will get sick. And because there are so many more vaccinated than unvaccinated people in this country, the immunized people who get sick are likely to outnumber the ones who aren't immunized.

To see how this works, imagine that measles strikes a school of 1,000 students. Of the 995 who have been vaccinated, ten become infected, while all five of the unvaccinated children in the school get sick. So although more vaccinated students got measles, the chances of coming down with the disease were much lower for people who got the vaccine (about 1 percent) than for people who didn't (100 percent).

No vaccine guarantees immunity to everyone who's vaccinated. For reasons we don't understand, some people who are vaccinated don't become immune and remain susceptible to the disease. And some people lose their immunity over time if they don't receive the recommended booster shots. But vaccination still offers the best chance of protection from infectious disease.

A study published in the Journal of the American Medical Association in July 1999 found that during a measles outbreak, unvaccinated people were 35 times more likely to get measles than vaccinated people. Several studies have since confirmed these findings.

Member Comments

MamaMuslimah, that's not the way immunity works - it isn't genetic. You can't inherit immunity, only develop it. If you wanted to transfer your immunity to your children you would need to have your spleen and lymph nodes removed and implanted in your child. The only reason Hep B is given at birth is that a large fraction of the most endangered population will never come back to any doctor's office again - it is the only chance to vaccinate them. If you have the follow through to come back when your child is ten or twelve and pay for the vaccine yourself without government subsidy then, yes, that works better but that is not who the recommendation was made for. None of the vaccine viruses are "being grown on aborted fetal tissue", that is a lie - they were ORIGINALLY ISOLATED from that tissue but they are grown on standard cell lines. There are no non-profits that have the money to begin producing vaccines - and there is essentially no profit in them, they are a break even.
posted 11/03/2011 by jaychaplin
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Here's why people are suspicious about vaccines: you've never seen your children die of childhood illnesses. You've never seen your siblings' kids die, you've never seen all of the neighborhood children die because of an outbreak. Nobody in the 21st century has any idea how DANGEROUS childhood diseases were--because vaccines stopped their spread. The risk from vaccine is vastly lower than the risks presented by rubella, diptheria, pertussis, mumps, measles, and all the others. Besides--the guy who started the anti-vaccine crusade has now been outed as a fraud. Trust the science and trust your doctors--not hearsay on the web.
posted 8/28/2011 by a BabyCenter Member
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It's stupid to give an example where the 5 unvaccinated kids get sick. That's not reality, and even though it's just an example, it is used to make people think that because you are unvaccinated you will get sick. At 32 years old, I've never been vaccinated for the influenza. I spend my days surrounded by kids (I'm a teacher) and have never gotten the flu. Most people I know who did get this vaccine, have gotten sick.
posted 3/24/2014 by a BabyCenter Member
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I know it sounds like no sense, but if you want to have a bit of true history about vaccines read a book called Katherine The Great, by Henry Troyat, she was the one person who took the risk of getting immunized against Smallpox in a time where people's faces got deformed if they survived, or the simply died of it, it's very interesting and shows exactly how it started
posted 4/08/2013 by adda76
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Try researching your state health dept's websites for current stats. In my state, there hasn't been a SINGLE case of rubella in over 10 years, and only a few isolated (never spread, confirmed by state stats) cases of measles from overseas travel. Also, with mumps, almost every single case in our state were in two groups of people: those confirmed as having been vaccinated (incl boosters) & those that were too young to have received the MMR. Mumps vaccine is only 80% effective at best (you can research this on the CDC's website), but mumps is the one vaccine that can cross the blood/ brain barrier and infect the meninges. (YES, the risk is much lower if you're immunized, but is the risk low enough not to consider a DELAYED immunization schedule?) Our babies are being immunized way too early with TOO MANY shots, during the time they RECEIVE immunity from their mothers anyway (if they're breastfeeding, for up to a year, & if not breastfeeding, for 6 mos). 2nd comment regarding Heb B...
posted 9/17/2012 by a BabyCenter Member
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What about those that were immunized in the school that never came in to contact with the virus? But we credit the immunization anyway? Right... If they worked fully, then we'd be able to pass on the immunity to our children. They offer a short-term sense of protection that is not guaranteed. Hep B at birth? Who are our infants having sex with? Are hospitals recycling needles? Loved this site another mom shared... An alternative schedule for vaccines if you choose to. And viruses being grown on aborted fetal tissue brought up ethical concerns for myself... Our bodies are not "machines" where we can just "program" immunity, but I also want the best for my children... If companies had our interest in mind - instead of profit - maybe I wouldn't be suspicious! Where is the non-profit vaccine maker?
posted 12/20/2007 by MamaMuslimah
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I agree that the idea behind vaccines preventing disease and outbreaks is a good thing. My only concern is that the vaccines that we currently have available to our children are not as safe as I think they should be. Too many questions about whether there is a link between speech delays, behavioral issues, ect and the ingrediants in the actual vaccine and the level/amount of ingrediants used in each vaccine and when they are added up as a combined total for the day after multiple shots are given at the doctors office. It's a tough choice for parents to make these days.
posted 11/18/2007 by a BabyCenter Member
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Are we seriously having Offit answer this?! He makes money off of vaccines and has other conflicts of interest. To those who say vaccines eradicated diseases, LOOK AT the data. The number of disease cases were already in a sharp decline BEFORE vaccines were introduced. We're messing with natural immunity and causing more problems. Just look at how parapertussis is changing things because of how the vaccine is now produced. And those who think vaccines are 100% safe, please stop listing Wakefield's shame as reason to believe their safety. There are plenty of other doctors and researchers who have proof that vaccines are not as safe as the government would have us believe them to be. Think of it in basic terms, too, with the adjuvents: Sure x amount of mercury/aluminum/formaldehyde/polysorbate is safe, but multiply that times the ridiculous amount of shots infants are subjected to -- that's NOT SAFE.
posted 3/26/2012 by a BabyCenter Member
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I am living proof that not only are vaccines not effective, but the supposed "deadly" diseases are not fatal. Yes they can be "potentially" fatal, but so can riding in a car, going swimming, or walking across the street. I was fully vaccinated as a child and still I got rubella, pertussis, and mumps, and while it was uncomfortable I can assure you I am not dead. Paul Offit is the most unreliable "expert" on vaccines out there. He makes money from vaccines, and in fact his rotovirus vaccine not only can cause deadly intestine problems but the cases of rotovirus in the vaccinated children is the same as in children who are not vaccinated. Vaccines have not eliminated disease, look at the charts and you will see they started to decline before vaccination became the norm. They come and go, and the biggest reason they are less today is our sanitation is much better. Many parents get bullied into shots because they are lied to and think kids can't go to school without them.
posted 8/16/2011 by mara17
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Thank you many times over for the information and websites. I have finally found a sensible and sane vaccine schedule. The more we bring attention and question these "authorities" regarding the amounts and what is in these vaccines, the higher the chance they will improve them!!
posted 10/01/2008 by a BabyCenter Member
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