The possible relationship between SIDS and vaccination has not been properly investigated. by Wendy Lydall, author of Raising a Vaccine Free Child.
THE CASE-CONTROL METHOD
A favourite method used by researchers who are looking at the relationship between vaccination and SIDS is the case-control method. Case-control studies compare babies who died with babies who did not die.
The researchers select a group of babies who died of SIDS within a particular geographical area, and these babies are called the cases. Each case is matched with two or three live babies who are called the controls. The vaccination history of the baby who has died is then compared with the vaccination histories of the two or three babies who have not died. Babies who have not received any vaccinations are excluded from the study.
In the case-control studies that have been published, researchers have found that when the live babies were at the age at which the case baby died, they had received more vaccine doses than those who had died. This leads the authors to conclude that vaccination does not cause SIDS, a happy conclusion for those who want to promote vaccination, but far from scientifically sound.
One problem with the case-control method is that it could be comparing fragile babies who are susceptible to dying from an immunological onslaught with tougher babies who can survive being injected with animal tissue, human tissue, peanut oil, attenuated germs, toxic metals, toxic chemicals, and genetically engineered yeast. Case-control studies can be useful for investigating something that is static at the time of death; for example, whether the baby was sucking a pacifier, or lying face down.
However, the effects of vaccination are not static; they are ongoing, and they are unknown. Case-control studies can also be useful if you take all the confounding factors into account, but in the case of vaccine susceptibility, no one yet knows what the confounding factors are. Controlling for factors that are known to increase the risk of SIDS does not mean that you are controlling for factors that increase the risk of SIDS from vaccination.
In the most recent case-control study, which was done in Germany, researchers found that the babies who died had had fewer vaccinations than the ones who were still alive, and that their vaccinations had been done later. 
The latter finding may be significant. Parents can be reluctant to turn up on time for vaccinations when they feel that their baby is unusually fragile, or when they know that vaccine reactions run in the family. Some parents who are not keen on vaccination eventually comply because of the extreme pressure that is put on them, but they do it later than at the prescribed time.
Interestingly, the researchers did find a statistically significantly higher rate of developmental problems, hospital admissions and special investigations, like x-rays or electrocardiograms, in the SIDS babies compared to the live babies.  This discovery might mean that the babies with these problems, who were only 22 percent of the SIDS babies, were more susceptible to dying unexpectedly, and that vaccination played no role in their deaths. Alternatively, it might mean that these babies were susceptible to an unknown effect of vaccination, and that vaccination killed them. A different study design would need to be used to ascertain whether vaccination played a part in the deaths of this 22 percent. The fact that these babies had had fewer doses of vaccine than the live babies with whom they were compared does not mean that they were not pushed over the edge by the vaccines that entered their bodies. It is illogical to say, “Baby A had 6 vaccines and is dead, while Baby B had 11 vaccines and is still alive, so that proves that vaccines had nothing to do with the death of Baby A.”
There has been some consideration of the role that metabolic disorders might play in making children susceptible to adverse reactions from vaccination, but while the possible relationship to SIDS has been considered by one group of doctors, there has not been an actual study. There are many types of metabolic disorders, but each one occurs in only a few children.
In 2010, a group of doctors published an article in which they considered the possibility that some children who were born with metabolic disorders may have died from the whole-cell whooping cough vaccine. The doctors paid special attention to a metabolic disorder called medium-chain acyl-CoA dehydrogenase deficiency.
After considering the biological pathways in children with medium-chain acyl-CoA dehydrogenase deficiency, the doctors concluded that one third of the babies who were born with this disorder, and who were also injected with the whole-cell whooping cough vaccine, could have died from resultant low blood sugar.  Because medium-chain acyl-CoA dehydrogenase deficiency is very rare, this amounted to only 39 babies per year in the USA.
The consideration of medium-chain acyl-CoA dehydrogenase deficiency was only done seven decades after the whole-cell whooping cough vaccine was introduced. There are more than four hundred metabolic disorders that need to be considered and studied. There may be other types of vulnerability apart from metabolic disorders that make babies susceptible to dying quietly from vaccination. Case-control studies are unable to detect deaths that occur because of individual susceptibility.
Long ago, I mentioned to a pediatrician who publishes articles about SIDS that I considered case-control studies to be an inadequate way of testing whether vaccination increases the risk of SIDS. He replied, “That’s the way it has always been done.”
Valentina A. Soldatenkova is a mathematician and physicist who has also expressed the opinion that case-control studies are inadequate for assessing the relationship between vaccination and SIDS. In her published critique of the existing case-control studies, she criticises the study designs employed and statistical methods used by researchers to conclude that there is no relationship between vaccination and SIDS. 
The Institute of Medicine in the USA has the job of publishing complicated whitewashes about vaccine side effects, and they, of course, have done exactly that in regard to the question of whether vaccination may cause some cases of SIDS. Their lengthy report on the existing studies concludes that “the evidence does not support a causal link” between vaccination and SIDS.
Soldatenkova says that their report should have stated that “the evidence is inadequate to accept or reject a causal relation between SIDS and vaccines.” 
Another type of study that is often quoted as proving that vaccination does not cause SIDS is the temporal study. Central to these studies is the assumption that if vaccination were to cause a sudden unexplained death, it would do so within 12 hours, or 24 hours, or 48 hours, or 7 days, or 14 days. [5,6,7,8,] No one knows what vaccines do once they get inside the body, so no one knows what the time frame is for a negative effect. Implying that they do know is bordering on fraudulent.
Antibodies only start appearing two weeks after vaccination, and the production of antibodies continues for a few more weeks. The researchers, who are sometimes being paid to do the study by a vaccine manufacturer, have no basis for assuming that any negative effects of the ingredients in vaccines would take less time to develop than it takes for antibodies to develop.
THE POSSIBLE LINK BETWEEN VACCINATION, BLOOD SUGAR, AND SIDS
It is possible that some SIDS deaths may be caused by low blood sugar. Dr. C. Horvarth reported that during a three-year period in New Zealand, the blood sugar level of 84 babies who had died inexplicably was measured at autopsy, and in 81 of them, the level was found to be below the normal range. 
Other studies have shown that low blood sugar is strongly associated with SIDS. [10,11,12,13] When the whole-cell whooping cough vaccine causes the level of blood sugar to drop, the drop starts at about 8 days after injection, reaches its lowest point at about 12 days after injection, and becomes normal at about 24 days after injection. 
PROMISING NEW PROTOCOLS
Many countries have passed legislation that an autopsy must be done after every SIDS death, and they have introduced protocols that have to be followed. This is a great step forward. Previously autopsies were only done if someone felt like doing one, and they could decide what to investigate and what to ignore.
One of the benefits of the introduction of autopsy protocols is that explanations are found for some of the otherwise mysterious deaths. In Germany, for example, a non-SIDS explanation for 11.2% of the SIDS deaths was found because of the autopsies. 
In the future, the protocols will help to identify ways to reduce the incidence of SIDS. In the mean time they help detect to infant abuse, and they help to prevent parents from being falsely accused of abuse. The protocols also mean that doctors can no longer write off blatantly obvious reactions to vaccination as SIDS.
The usefulness of the autopsies would be enhanced if they were to include an assessment of the blood sugar level at the time of death, which can be done even though blood glucose continues to be broken down for a short while after death. [10, 16]
SIDS has been occurring since long before vaccination was invented.  As records of its incidence were not kept until relatively recently, it is not possible to know whether the rate of SIDS in modern times is different to what it was in the distant past. To gain more insight into the distressing phenomenon of SIDS, blood sugar levels at the time of death should be assessed in every SIDS autopsy, and every vaccine that is recommended for infants should be tested to find out whether it causes blood sugar levels to drop at any time after vaccination.
1. Vennemann, M.M., Butterfaß-Bahloul, T., Jorch, G., Brinkmann, B., Findeisen, M., Sauerland, C., et al. (2007). “Sudden infant death syndrome: No increased risk after immunization.” Vaccine: 25(2), 336–340.
2. Vennemann, M.M., Findeisen, M., Butterfass-Bahloul, T., Jorch, G., Brinkmann, B., Kopcke W. et al. (2005). “Infection, health problems, and health care utilisation, and the risk of sudden infant death syndrome.” Archives of Disease in Childhood: 90(5), 520–522.
3. Wilson, K., Potter, B., Manuel, D., Keelan, J., & Chakraborty P. (2010). “Revisiting the possibility of serious adverse events from the whole cell pertussis vaccine: Were metabolically vulnerable children at risk?” Medical Hypotheses: 74(1), 150–154.
4. Soldatenkova, V.A. (2007). “Why case-control studies showed no association between Sudden Infant Death Syndrome and vaccinations.” Medical Veritas: 4, 1411–1413.
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