Babies born to mothers who have been naturally immunized against measles have 3 times as many antibodies against the virus than babies born to vaccinated mothers. Furthermore, these babies keep those antibodies for 4 times longer, according to a study published in the British Medical Journal.
The researchers measured the immune response to measles for both sets of expectant moms at 36 weeks, then took samples from the baby at birth (cord blood), 1, 6, 9, and 12 months. Naturally immune moms had a three times the number of antibodies to measles and passed this on to the newborns- 26% of vaccinated women didn't even register antibodies to the test. This meant that a quarter of the babies born to vaccinated moms had no maternal antibodies to measles whatsoever, and on the whole this group had statistically significantly fewer antibodies to measles versus the naturally immune infants. Three months later, twice as many infants in the natural immunity group still had antibodies to the virus (60% vs. 29%), and at 6 months all but 1 of the 11 remaining positive titers (11/72) came from babies of naturally immune moms. The average time to immunity loss was 3.78 months for infants of naturally immune women and less than a month for infants of vaccinated women.
Ironically (or not- the study was funded by GlaxoSmithKline), the authors used their findings to suggest that since all of the infants had lost the maternal antibodies by 9 months of age, policy makers should consider immunizing babies against measles earlier than most governments recommend. They even claimed that breastfeeding had no effect on the loss of maternal antibodies, and while accurate, the statement is completely misleading.
The immune system protein this study measures is called immunoglobulin G, or IgG for short. For the sake of simplicity, let's call them apples. When a pathogen enters the body, the first line of defense are the mucosal linings of the eyes, nose, mouth, and gastrointestinal system. These linings are filled with IgA, which we'll call oranges. Breastmilk is high in IgA and "paints" the linings of the protective layers to defend against invaders. The next line of defense in the bloodstream is a protein called IgM- think of them as the Marines. IgM levels increase from about 20% of adult levels until 2 years old. The next responders in the bloodstream are IgG, our apples, and these antibodies are the ones that remember what the pathogen looks like in the future. However, unless our skin gets punctured, nothing comes into the body without coming in contact with IgA, oranges, first.
Leuridan et al attempt to pull a fast one by saying maternal apples disappear at 9 months of age, even if the infants are breastfed. They say that apples don't enter through the mother's milk (duh, it's mainly full of oranges), so the babies should be vaccinated. What they fail to admit is that they're measuring the apples but not measuring oranges, and while apples in the blood may be falling, the oranges in breastfed infants are getting stronger. Both apples and oranges are able to fight the measles, so the disappearance of apples doesn't mean the breastfed baby is totally unprotected- it also has a mini-Marine Corps in the bloodstream to back it up.
Furthermore, if it's the mothers who have contracted measles naturally that end up delivering the babies with the stronger immune systems, it is ridiculous to suggest the continual weakening of a society by artificial means. A quarter of the mothers and babies had no protection against the virus even though they were vaccinated. This doesn't require a "booster," it requires a complete shift in thinking of how we're going stop the Sickest Generation from having a complete immunological meltdown.
Leuridan E, Hens N, Hutse V, Leven M, Aerts M, Van Damme P (2010). "Early waning of maternal measles antibodies in era of measles elimination: longitudinal study." British Medical Journal 340:c1626
