Did you know immunity from vaccines wears off after 5-10 years!?
Initially, when looking into how long immunity from childhood vaccines last, sources such as the CDC and the WHO claim almost all vaccines are 100% effective and last a lifetime. Upon digging deeper and reading further research, this does not seem to be the case. Many vaccines have been found to have "waning-immunity", which creates a risk within itself.
According to The Immunisation Advisory Centre, "vaccine immunogenicity is a measure of the immune response to a vaccine and usually involves measuring specific antibodies in the blood. For some, but not all vaccines, a defined threshold of specific antibody levels have been correlated with protection. However, this does not definitively tell us if a person is fully protected against disease. If good immune memory has been established, a large rise in antibody levels occurs following a booster dose of vaccine."
As the Britannica explains, "It has been known for centuries that persons who contract certain diseases and survive generally do not catch those illnesses again. Greek historian Thucydides recorded that, when the plague was raging in Athens during the 5th century BCE, the sick and dying would have received no nursing at all had it not been for the devotion of those who had already recovered from the disease; it was known that no one ever caught the plague a second time. The same applies, with rare exceptions, too many other diseases, such as smallpox, chickenpox, measles, and mumps. Yet having had measles does not prevent a child from contracting chickenpox or vice versa. The protection acquired by experiencing one of these infections is specific to that infection; in other words, it is due to specific, acquired immunity, also called adaptive immunity.
There are other infectious conditions, such as the common cold, influenza, pneumonia, and diarrheal diseases, that can be caught again and again; these seem to contradict the notion of specific immunity. But the reason such illnesses can recur is that many different infectious agents produce similar symptoms (and thus the same disease). For example, more than 200 viruses can cause a cluster of symptoms known as the common cold. Consequently, even though infection with a particular agent does protect against reinfection by that same pathogen, it does not confer protection from other pathogens that have not been encountered.
Acquired immunity is dependent on the specialized white blood cells known as lymphocytes. This section describes the various ways in which lymphocytes operate to confer specific immunity. Although pioneer studies were begun in the late 19th century, most of the knowledge of specific immunity has been gained since the 1960s, and new insights are continually being obtained."
The immune system is very complex. Learn about Lymphocytes, the role they play in the immune system, and more HERE.
Below, we will go through different vaccines and the duration of immunity they have, including additional information about the vaccine and waning immunity.
Hep B
This vaccine is recommended to be given at birth and again at 2 and 4 months. However, when given in combination with other vaccines like DTaP, the Hep B vaccine can also be given at 6 months of age. It is also generally not recommended for adults unless at specific risk. Hep B vaccines contain Recominant Hepatitis B viruses.
The CDC claims that protection from the Hep B vaccine can last up to 20 years. Studies have shown that only after three years, participants had low antibody levels to Hepatits B vaccination. People with immunodeficiencies are particularly at higher-risk to waning immunity after Hep B vaccination. Some people vaccinated may still contract Hep B.
DTaP/TDaP/TD
DTaP vaccines are given to children at the ages of 2, 4, 6, 15-18 months and again at 4-6 years of age. TDaP vaccines are given to children between 11-12 years of age. TD or TDaP vaccines are recommended for adults every 10 years after their first dose. Both DTaP and TDaP vaccines contain Diphtheria and Tetanus Toxoids and Acellular Pertusiss. TD vaccines contain only Diptheria and Tetanus Toxoids.
Diphtheria
According to the WHO, vaccination againstion Diphtheria may induce some protection against symptomatic infection but does not prevent the spread of the disease. They have found antibody levels in individuals up to 15 years after initial vaccination.
A recent study has shown nearly 60% of adults over the age of 20 no longer have vaccine-induced immunity to Diphtheria. Even immediately after vaccination antibody levels remain low, a considerable amount of adults, particularly the elderly, have no protective antibodies.
Tetanus
Due to the inability to gain life-long immunity to Tetanus bacteria, those who vaccinate must receive booster vaccines. The CDC explains how "protective levels" begin to wane after 10 years, but some individuals levels can fall below minimal before 10 years.
Tetanus cannot be transmitted from person to person and outbreaks rarely occur.
Pertussis
Before the 1990's, whole cell Pertussis vaccines were used. After an increasingly amount of children becoming injured from these vaccines and the public becoming concerned about the safety of these vaccines, whole cell Pertussis vaccines were discontinued and acellular pertussis vaccines came to market.
According to the CDC, immunity to Pertussis after vaccination can last up to 20 years. However, more recent research shows that effectiveness declined rapidly within 4 years. This has raised the question if acellular Pertussis vaccines are the cause of Whooping Cough outbreaks. In 1996, the Netherlands had an outbreak that was more prevalent with highly vaccinated communities.
A 2014 Pertussis outbreak in California was found to be the cause of failing vaccines and 83% of those infected were previously vaccinated. This FDA study explains the waning immunity to Pertussis after vaccination and how it has contributed to Whooping Cough outbreaks among vaccinated children.
Hib
This vaccine is typically given at 2, 4, 6, and 15 months of age and generally not recommended for adults unless at specific risk. The Hib vaccine contains Haemophilus influenzae type b conjugate with either Meningococcal Proteins or Tetanus Toxoids.
According to the CDC, immunity from Hib vaccines is expected to last 1 1/2 - 3 1/2 years. Before the Hib vaccine was introduced most children obtained natural immunity by 5-6 years of age through infection and in contrast to vaccine-induced immunity, natural infection is thought to give 4-10 years of protection.
Some recent research has indicated a correlation between Hib vaccines and a "shift in capsular serotypes of invasive H. influenzae disease" and even when vaccinated, some individuals will still contract the disease.
Polio
This vaccine is given to children at ages 2, 4, and 6 months and again at 4-6 years of age. It is generally not recommended for adults unless at specific risk. The polio vaccine contains three strains of inactivated Poliomyelitis viruses, Type 1 (Mahoney), Type 2 (MEF-1), and Type 3 (Saukett).
Read the Polio vaccine manufacturer package insert HERE.
For nearly 40 years in the US, the Polio vaccine was a Live virus vaccine, given orally (OPV). In 2000, a vaccine-derived Polio outbreak occurred and the US withdrew from using OPV, other countries do still use Live Polio vaccines and have continued to cause vaccine-derived outbreaks.
MMR
This vaccine is given to children at 12-15 months and again at 4-6 years of age. It is also recommended for adults over the age of 18. The MMR vaccine contains live components of the Measles, Mumps, and Rubella viruses.
Read the MMR vaccine manufacturer package insert HERE.
Measles
According to the WHO, up to 15% of children fail to develop immunity to the first dose, which is why a booster dose is recommended. Most babies receive their first dose around 1 year; the second is given usually before kindergarten. “Protection” is supposed to last up to 11 years. This means, assuming a child actually gains immunity, any will have worn off completely by 16 years of age.
The vast majority of adults in this country are no longer immune. One study found, "As measles vaccination coverage increases, the circulation of wild measles will decrease, and vaccine-induced antibody is less likely to be boosted. Thus, new epidemics may occur in vaccinated areas."
Also according to the WHO, vitamin A supplements and adequate nutrition are key to preventing measles and complications.
Rubella
According to the CDC, immunity to Rubella from the MMR vaccine can decrease within 9-14 years after initial vaccination. One study indicated rubella antibodies 15 years after vaccination. Another study showed a third of the individuals at the age of 17 years, had low levels of rubella antibodies.
More recent research has demonstrated that even when vaccinated, Rubella infection can persist in some individuals, specifically those who are immunodeficient.
Mumps
According to the CDC, one dose of the MMR vaccine only gives average effectiveness of 78%. Two doses give 88% and immunity is only expected to last for up to 10 years.
A growing number of previously vaccinated individuals, specifically college students, have been contracting mumps, causing outbreaks. Evidence has shown, waning immunity from the MMR vaccine is a likely reason.
Varicella Zoster
This vaccine is given at 12-15 months of age and again at 4-6 years of age. Adults under 50 are recommended to be vaccinated against Varicella, commonly known as Chicken Pox, with 2 doses if born after 1980. Adults over 50 are recommended to receive a Zoster vaccination, otherwise known as Shingles. The Varicella vaccine is a Live virus vaccine and there are two Zoster vaccines, one Live and one Recombinant.
Read the Varicella vaccine manufacturer package insert HERE.
Clinical trials have shown children vaccinated with 2-doses of Varicella vaccines had antibodies 10 years after vaccination. Analysis of data indicates " incidence rates of breakthrough varicella increased more than 12 times from the first year of vaccination to year 8 after vaccination". Some studies have shown those vaccinated against Varicella may hide the virus and can cause Zoster infections later on in life.
Multiple studies have revealed vaccine-induced infections after Varicella Zoster vaccination. An analysis of 36 individuals over the age of 60 vaccinated with Zostavax was conducted in 2011. Vaccine-virus DNA was found in 50% of the subjects swabs taken from skin inoculation sites immediately after vaccination and in almost 60% of the subjects saliva on day 28 post-vaccination.
HPV
This vaccine can be given to children as young as 9. It is given in either a 2 or 3-dose series. It is generally not recommended for adults unless specifically indicated. There are three different vaccines for HPV, also known as Gardasil, the most commonly used is Gardasil-9. There are over 200 different types of Human Papillomaviruses, this vaccine contains 9 different Recominant types, which include types 6, 11, 16, 18, 31, 33, 45, 52, and 58.
Read the Gardasil-9 vaccine package insert HERE.
According to the National Cancer Institute, immunity from the Gardasil vaccine can last up to 10 years however, according to the manufacturer, Merck, immunity has not been established. In a 2015 review, it was revealed that immunosuppressive therapies likely reduce immune responses to HPV vaccines.
It is important to note, 90% of primary HPV infections clear naturally.
Read more about vaccines, common childhood illnesses, and more HERE.
*vaccinating is a choice, you do not have to vaccinate but if you do, you should be educated and informed. use this information to further your knowledge about vaccines to make the best decision possible for you and your family.
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