A recent review found non-live vaccines tend to increase a person’s risks of all-cause mortality, as well.
By Marina Zhang
Apart from potentially preventing a particular disease, vaccines may cause persistent nonspecific effects that can affect a person’s lifetime survival.
In a review published on Dec. 26 in Vaccine, researchers found that non-live vaccines like influenza, COVID-19, hepatitis B, and diphtheria-tetanus-pertussis (DTaP) tend to cause adverse nonspecific effects (NSE), increasing a person’s risks of all-cause mortality and the potential risk of infections from diseases they are meant to protect against.
A live vaccine contains a weakened form of the pathogen, which is less virulent but capable of replicating in the body, thus mimicking the actual disease progression. Non-live vaccines use inactivated viruses, fragments, or genes of the pathogen to trigger an immune response without pathogen replication.
Live vaccines elicit a much stronger immune defense, typically requiring only one shot, while non-live vaccines result in a weaker response, often necessitating multiple shots.
So far, research has identified several non-live vaccines that cause adverse nonspecific effects, namely DTaP and Tdap, influenza H1N1, malaria, hepatitis B, inactivated polio, and COVID mRNA vaccines.
The Vaccine study singled out DTaP, influenza, malaria, hepatitis B, and COVID mRNA vaccines.
On the other hand, live vaccines such as the oral live polio vaccine (OPV), the Bacillus Calmette-Guérin (BCG) vaccine for tuberculosis, and the smallpox vaccines all have beneficial nonspecific effects, according to the study.
“Live vaccines … elicit epigenetic alterations that train the innate immune system and increase immunity to unrelated infections. In opposition, non‐live vaccines may promote ‘tolerance’ that increases susceptibility to unrelated illnesses,” the authors suggested.
The study was primarily based on decades of work from Danish researchers Dr. Christine Stabell Benn and professor Peter Aaby.
“Our work is a tribute to their great scientific work that has not been recognized,” biologist Alberto Rubio-Casillas, one of the study’s authors, told The Epoch Times.
Non-Live Vaccines Are Like an ‘Ill-Prepared’ Army
“Historically, we’ve thought about the innate immune system as the first line of defense,” Dr. Benn told The Epoch Times.
It was thought that innate immunity could not store memory. To use war as an analogy, the immune system’s “army” could not learn from previous battles with pathogens. Adaptive immunity, on the other hand, could learn and be trained, forming antibodies to fight against the infection.
Therefore, for a long time, vaccines were evaluated based on their effects on the adaptive immune system, and antibodies were measured following vaccination.
But researchers in the Netherlands have since shown that the innate immune system can be trained. After vaccinating people with the BCG vaccines and harvesting some of the patients’ innate immune cells, researchers found that after vaccination, the innate cells exhibited a more robust immune response and demonstrated improved clearance of tuberculosis, as well as other bacteria and fungi when compared to patients’ prevaccination status.
However, the opposite was shown for non-live vaccines.
Thus, the innate immune system actually does learn something from its previous battles. This is called trained innate immunity.
Live vaccines, which mimic an actual disease, enhance the effectiveness of the innate immune system in defending against infections. Non-live vaccines, on the other hand, weaken the immune system’s ability to fend off infections.
In a TED talk, Dr. Benn compared infections to a competitive tennis match and live vaccines to a tennis coach. The tennis coach may change tactics and strategies, training the body to have “a wide variety of tricks” against the pathogen. Non-live vaccines, however, are like tennis ball machines that shoot out balls at a specific speed and spot. If a person only trains with a tennis ball machine, he or she will be less prepared for an actual match.
“So you may be ill-prepared and even worse off when a real opponent enters the court, and the balls start coming and hitting elsewhere than what you trained for,” Dr. Benn said.
Nonspecific Effects
Some vaccines result in positive nonspecific effects, but others may result in overall adverse nonspecific effects. The order in which vaccines are administered also factors in.
While non-live vaccines cause negative NSEs, administering a live vaccine after a non-live one neutralizes negative NSEs, Dr. Benn said.
This has been shown in studies evaluating the safety of measles vaccines, which are often given around the same time as DTP, a non-live vaccine. Studies have found that if the measles vaccine are given after the DTP vaccine, there is an overall positive effect, whereas if this order is reversed, then there is a negative effect.
“It seems that effects are strongest as long as the vaccine is the most recent vaccine,” said Dr. Benn.
Dr. Benn added that the BCG vaccine has long-term beneficial nonspecific effects “in spite of other vaccines being given afterwards.”
The DTaP vaccine has arguably the most evidence of adverse nonspecific effects. Girls who took the DTaP vaccine had a 50 percent higher risk of dying than boys who got it. Compared to girls who were DTaP-unvaccinated, vaccinated girls’ risk of dying was over 2.5 times higher.
Dr. Benn’s studies have generally shown that girls are at a greater risk of developing adverse nonspecific effects after being administered non-live vaccines.
Live Vaccines Replaced With Non-Live Vaccines
Non-live vaccines are increasingly replacing live vaccines. For example, live oral polio vaccines are no longer available on the U.S. market, and a non-live version is administered instead.
This substitution of live vaccines with non-live can pose potential health risks to the general immunity of the population, as the immune systems become less trained and potentially “lazy,” said Dr. Benn.
However, the main reason non-live vaccines are preferred over live vaccines is that they are believed to be safer for people with depleted immune systems.
Since a live vaccine causes mild disease in the body, people with acquired immunodeficiency syndrome can develop a disease from the injection and may die since their bodies are unable to clear infections. Conversely, non-live vaccines comprise only disease components, so they cannot induce disease.
In this aspect, Dr. Benn said that the “risk of getting the real disease with the live vaccines has been seen as a bigger threat than I think it deserves.”
Research suggests that people with weaker immune constitutions due to age or chronic disease may sometimes benefit from having their immune systems trained using live vaccines.
In one study involving hospitalized older patients randomized to get the BCG vaccine or a placebo, the incidence of disease among those who took the BCG vaccine was about half the incidence of disease in the placebo group.
Health Authorities Still Skeptical
Despite the evidence suggesting the potential superiority of live vaccines, Dr. Benn’s research has been largely unacknowledged by the mainstays of academia.
“In my interpretation, whereas most researchers now acknowledge nonspecific effects, the major health organizations are reluctant to accept our findings because [the findings] imply the possibility that some vaccines may sometimes be harmful. So it is easier just to dismiss the whole thing,” she said.
“The vaccine skeptics, on the other side, may find that our observations on non-live vaccines confirm their worst fears—vaccines can be harmful—but they may be more reluctant to accept the beneficial effects. And their focus on the negative effects may make the vaccine supporters take an even more rigid stance.”
Immunologists now largely agree that some vaccines cause nonspecific effects, but how these effects should be quantified remains controversial.
This is because the nonspecific effects of vaccines are dependent on context, whereas a vaccine’s specific effects are generally considered context-independent. For example, females may make more antibodies than males and younger people more than older, but most people still get some form of immunity.
“In contrast, because the nonspecific effects act on the broader innate and general immune system, they are dependent on other factors going on in the immune system … like other health interventions that can alter and modify the nonspecific effects,” Dr. Benn explained. Not everybody will have the same benefit, she added.
Additionally, pharmaceutical companies may be more reluctant to produce live vaccines because they are harder to culture and manufacture.
“If you have ever tried to bake with sourdough, it’s a little bit like live vaccines; they are very dependent on the temperature of the room, the water used to culture it, and so on,” said Dr. Benn.
“But basically, all the live vaccines I’m talking about—they have no patents anymore, they’re super cheap to produce, and it’s some of the cheapest vaccines we have to make.”
Vaccine Safety: NSEs Versus Adverse Events
Though live vaccines tend to cause positive NSEs, that is not to say they cannot potentially cause adverse events. NSEs are considered a separate entity from adverse events, Dr. Benn explained. According to her, in rare cases, live vaccines may induce the actual disease in some recipients, such as people born with gross defects in their immune systems or who have severe immunodeficiencies, like fulminant AIDS.
In the case of COVID-19 vaccines, live vaccines were likely not considered due to concerns about the formation of recombinant viruses when a vaccinated person comes into contact with the circulating viral strain.
However, despite their potential beneficial NSEs, the COVID vaccines may still be associated with adverse events due to the presence of highly toxic spike proteins, which studies now link to long COVID and vaccine injuries.
In the medical textbook “The Immune Response,” the authors wrote that, in isolated cases, live viral strains administered to individuals can regain virulence, causing disease in recipients. Additionally, there is a risk of contamination with other viral strains during manufacturing.
