According to some studies, systemic infections such as measles, hepatitis A and tuberculosis infection prevent allergies and asthma, because some bacterial and viral infections shift the immune response toward Th1.
BCG vaccination, however, does not prevent allergies and asthma.
Recruits in Italy, who had antibodies to hepatitis A, had asthma and allergic rhinitis 2 times less often than soldiers who did not have antibodies. Recruits who had older brothers also suffered from allergic diseases less often, which means that hepatitis A is not the only infection that reduces the risk of allergic diseases. In Italy, hepatitis A was an endemic disease in the 1970s, they were usually infected in childhood and passed asymptomatically. research also reveals in recent decades feedback antibodies to hepatitis A and allergies in different countries.In the United States in the 1970s, the eldest generation had more antibodies to hepatitis A than the younger generation, whereas the younger generation had more atopic diseases.The prevalence of atopy in children with antibodies against hepatitis A virus and hepatitis B virus. 2006, Kocabaş, Turk J Pediatr
Children who did not have antibodies against hepatitis A had 9 times more asthma and allergic rhinitis, those who did not have hepatitis B antibodies were 5.9 times more likely to have allergic diseases. More: .Chickenpox in childhood is associated with decreased atopic disorders, IgE, allergic sensitization, and leukocyte subsets. 2012, Silverberg, Pediatr Allergy Immunol
Chickenpox disease up to the age of eight is associated with a reduction in the risk of asthma by 88%, allergic rhinoconjunctivitis by 84%, atopic dermatitis by 43%, and allergic sensitization by 89%. In cases of chickenpox, IgE, responsible for allergic reactions) remains low for more than 10 years after the disease.
9.1% of children in the US suffer from asthma and 17% have atopic dermatitis.
Herpes infection (including chickenpox) in the first 3 years of life is associated with a 2-fold reduced risk of asthma. 5-7 viral infections in the first 3 years of life are associated with a reduction in the risk of asthma by 68%, and 8 and more viral infections - by 84%.
Runny nose, two or more times during the first year of life reduces the risk of asthma by 48%, and wheezing by 40% .Children also reduces the risk of allergies.
In an analysis of 11,000 children who received a whole-cell vaccine in Canada, those who received the first dose of the vaccine two months later than usual developed asthma far less often (2-fold lower chance). Furthermore, those who received all three doses of the vaccine later in childhood had a 2.5-fold lower risk of developing asthma.
This phenomenon is due to the fact that the immune reaction shifts towards Th2. The exact cause of asthma is not yet known, but according to one of the prevailing theories, asthma is caused by increased hygiene. When children grow up in an extremely sterile environment, they do not come into contact with bacteria. This leads to the production of IgE antibodies. These IgE antibodies are responsible for asthma, allergies, dermatitis, and other problems that are much more common in vaccinated children. This is because vaccinations shift immunity towards Th2, which happens directly (due to vaccine antigens), and indirectly (due to protection against bacteria) affected.
The vaccinated had asthma twice as often as the unvaccinated. The authors believe that 50% of asthma cases (2.9 million) in US children and adolescents would be prevented if the DTP or tetanus vaccination was not administered. More: Early childhood infection and atopic disorder. 1998, Farooqi, Thorax
In vaccinated with whole-cell vaccine, the risk of allergy was 76% higher. In those who took antibiotics in the first two years of life, the risk of allergy was 2 times higher.
Taking one course of antibiotics increased the risk of developing an allergy by 85%, two courses of antibiotics increased the risk 3-fold, and three courses of antibiotics increased the risk 8-fold.
Those who had measles and had not received the vaccine, had a 45% lower risk of developing an allergy (note: in this case there was no statistical significance).
Those individuals who had been vaccinated with a whole-cell vaccine, had a 5.4-fold greater chance of developing asthma compared to unvaccinated individuals.Pilot comparative study on the health of vaccinated and unvaccinated 6- to 12-year old U.S. children. 2017, Mawson, JTS
The study compares homeschooled children in four states of the USA. 405 vaccinated and 261 unvaccinated children.
Vaccinated children had chicken pox 4 times less often, whopping cough – 3 times less often and rubella – 10 times less often.
Vaccinated children had otitis media 4 times more often and pneumonia – 6 times more often.
Those vaccinated had allergic rhinitis 30 times more often. They had allergies 4 times more often, ASD – 4 more often, ADHD – 4 times more often, eczema – 3 times more often, learning disabilities – 5 times more often, neurological disorders – 4 times more often. Vaccinated children had any type of chronic illness 2.5 times more often.
Vaccinated children used allergy medicines 21 times more often, antipyretics – 4.5 times more often, ear-drainage tubes – 8 times more often. They went to see a doctor, due to illness, 3 times more often and were hospitalized 1.8 times more often.
Some more interesting results from this study: risk of neurological disorders associated with the use of antibiotics during pregnancy (2.3 times), use of medicine during pregnancy (2.5 times), prematurity (5 times), ultrasound (1.7 times), and ultrasound done more than 3 times during pregnancy – 3.2 times.
The number of neurological disorders in vaccinated children (14.4%) coincides with the CDC studies (15%). The number of learning disabilities also coincides (5.6% of the vaccinated children in this study, and 5% according to available statistics).
However, judging by this study, there is already 3.3% of autistic children among vaccinated, i.e. 1 in 30 children. But, perhaps, it is an overestimation, as it is likely that children with ASD are homeschooled more often. (According to the CDC 2.24% of children are with ASD, i.e. 1 in 45 in 2015 and 1 in 36 in 2017).
Vaccination of a premature baby is associated with a 14 times increase in the risk of neurological disorders.
New Zealand, 23 unvaccinated (against DTP and Polio) out of 1,256 10-year old children. Out of the vaccinated children 23% had asthma, 22% got consults on asthma, and 30% had allergies.
There wasn’t a single case of asthma, or consults on asthma, or allergies among the unvaccinated children.
Children vaccinated against tetanus or with the DTP vaccine had asthma twice more often, allergies – 63% more often, and sinusitis – 81% more often, than the unvaccinated ones.
Among the children vaccinated with the DTP vaccine, 56% had asthma, chronic rhinitis or dermatitis. Among the unvaccinated ones only 9% had those diseases.