For babies who are allergic to eggs, the vaccine should be given with caution

Eggs are the medium of some vaccines, and some eggs allergy babies will be at risk of vaccination, which is easy to cause allergic reactions.

Eggs are a major source of dietary protein in early infancy and early childhood, and they are rich in nutrients. But what is not well known to the public is that it is also the medium for many vaccines, that is, some vaccines contain egg components in the composition. What should the baby with egg allergy do, can it still be vaccinated? Is there any risk?

High incidence of "egg" allergies

Eggs are our food from snacks to big ones and no one is unfamiliar with it. But there aren't many people who really understand it. Egg composition: shell accounted for 8% to 11%, egg white (egg white) accounted for 56% to 61%, egg yolk accounted for 27% to 32%. The egg white part is 10% protein, 88% is water, the egg yolk part is 50% water, 34% fat, and 16% protein.

Look at the ingredients of eggs is not unusual, but why is it sensitive? Studies have confirmed that allergens in eggs are mainly present in egg whites. Egg whites contain 23 glycoproteins, and it has been found that there are five protein components in egg whites that bind to human serum lgE to cause allergic reactions, which are egg mucin, egg albumin, oval transferrin, lysozyme, and oomycin[1].

Egg allergy is the most common allergic phenomenon in infants and children [2], especially in children with allergies and asthma. The incidence of egg allergies reported around the world is relatively close, basically between 1% and 9%. Although the manifestations of egg allergy in children are mostly mild, egg allergy has a great impact on children's bodies and even the quality of life in adulthood.

Egg allergies need to be taken seriously

Babies can cause allergies for a variety of reasons. Such as: genetics, time and method of initial exposure, and dosage. Most studies have shown that after adding solid food supplements to the baby, the sensitization rate of adding eggs early is lower than that of adding late, and adding egg yolks first, crushing 1/4 of the yolk into a powder to dissolve in rice paste, or steaming chicken cakes for babies can reduce the sensitization rate. In addition, the body's reactivity, gastrointestinal mucosal development, viral infections, and stability of the intestinal flora also cause egg allergy.

Egg allergies can trigger mast cells and basophils to release some chemicals. For example, histamine prostaglandins and leukotrienes dilate and cause rubella and rash, cause spasm of smooth muscles in the gastrointestinal tract and cause abdominal pain and diarrhea, cause bronchial smooth muscles to contract, and cause dry cough and wheezing [3].

Not only that, if there is egg allergy in infants and young children in the early stage, this is also a hidden danger for other allergies in the later stage. Most critically, egg allergies can also affect the injection of some vaccines. Vaccines are a powerful weapon to protect your baby's health.

The indispensable "sprout-egg" relationship

Eggs are the medium for some vaccines, which are all viral vaccines, and there are two main manufacturing processes. One is to grow the virus in chicken embryonic fibroblasts, which theoretically do not contain eggbumin. Such as measles vaccine, rubella vaccine, mumps vaccine, and rabies vaccine for uncommon chicken embryonic cells.

The other is to grow the virus in the sac fluid of the chicken embryo incubation, a process that may retain ovalbumin, commonly with relatively low flu vaccines and less common yellow fever vaccines with relatively low levels.

The degree of allergy determines whether or not to vaccinate

Based on the manufacturing process of leprosy and other vaccines, the third part of the Chinese Pharmacopoeia (2010 edition) published in mainland China in 2010 no longer regards egg allergy as a contraindication to vaccination of measles rubella combined with live attenuated vaccines. So eggs allergy babies can be assured of these vaccines: measles vaccine, leprosy vaccine, mumps vaccine and mumps vaccine, chicken embryonic rabies vaccine.

However, for influenza vaccines and yellow fever vaccines that may contain oval albumin, eggs allergy babies should be cautious. Studies have shown that if people with severe egg allergy, trace amounts of egg white protein can cause allergies, so for yellow fever vaccine, it is not recommended for people with egg allergies to be vaccinated.

As for the commonly used influenza vaccine, according to expert advice [4], children with egg allergy should prefer a vaccine without oval albumin, and if there is no such vaccine, it depends on the degree of allergy.

If the egg allergy is caused only by a local rash, it should not be vaccinated, while if the allergic reaction is more severe, such as pseudomembranous laryngitis, it should not be vaccinated. If the vaccine is non-essential, you can take 1/10 of the vaccine first, observe the reaction and then give the remaining 9/10. Or opt for a flu vaccine that is low in ovalbumin. Different manufacturers and batches of ovalbumin are different.

In addition, if you want to determine whether the baby has egg allergies, you can eat some eggs before adding complementary food to the baby, and then feed the baby to see if the baby has an allergic reaction to the egg. Egg antigens can be transmitted to fetuses and infants through the placenta and milk, causing allergies to occur, and egg antigens can be detected in breast milk after 8 hours of egg consumption by lactating mothers, and the amount of antigen is related to the amount of food [5]. Or before receiving the corresponding vaccine, take the baby to the hospital to draw blood, do an egg allergen test, and confirm that there is no error before vaccinating. Allergies can be big or small, but they must not be taken lightly.

bibliography:

[1] Escudero C，Quirce S，Fernández -Nieto M，et al．Egg white proteins as inhalant allergens associated with baker＇s asthma［J］．J Allergy，2003，58（7）：616－620．

[2] HeineRG,LaskeN,HillDJ.Thediagnosisandmanagementofeggaller-gy[J]. CurrAllergyAsthmaRep,2006,6(2):145- 152.

[3] Scurlock A M, Lee L A, Burks A W. Food allergy in children[J]. Immunol Allergy Clin North Am,2005(2): 369-388.

Zhang Jianhua,Chen Ling. Clinical diagnosis of egg allergy in children and recommendations for influenza vaccination[J].Practical Pediatric Clinical Journal,2010,25(21):1611-1613.

[5] Palmer D J, Gold M S, Makrides M.Effect of cooked and yaw egg consumption on ovalbumin content of human milk:A randomized, double-blind, cross-overtrial[J]. ClinExp Allergy, 2005, 35(2):173-178.