So to end my three part expansion on vaccination which started with Why we Should Be Vaccinated and then listed some common Fallacies along with a primer on immunology, I have a “little” piece on the most frequently asked questions submitted from a variety of sites on vaccines.
1. How do Vaccines Work?
- For this you need to go read a little about the immunology of the body. It’s not as fancy as people make it out to be (any questions? Write them in. I Shall try and work them into a future post.
- Vaccines act like a trainer for your immune system providing it a weakened, dead or pieces of a pathogen. The body produces proteins that attack these specific organisms but as the “pathogen” (fancy medical speak for germ) is weak it is less likely to make you sick and your body’s defence system (immunity) is more likely to kill them. The body then stores the cells that make these for future use.
- When a real pathogen appears your cells are ready to activate and multiply and destroy the invader even before it causes the clinical effect of it’s arrival.
2. Do Vaccines work against Bacteria or Viruses?
- They work against both. There are also some that affect the “toxin” of a bacteria such as the Tetanus Toxoid vaccines.
- There are also plans to produce vaccines against parasites such as malaria.
3, How Come Vaccines are not 100% Effective?
- You are basically chemistry. Your entire body functions through purely chemical processes. Even your thoughts are based in such chemistry. This does mean we aren’t exactly alike in our immune responses. The vaccine protects the MAJORITY of people from the disease. There are some whose immune system doesn’t respond in the same way or for some reason isn’t as effectively protected as the majority. They will still be capable of catching the disease albeit at a reduced rate since the vaccine still provides a partial protection
- In some cases the pathogen that affects a vaccinated individual may be of a rare strain that isn’t covered by the vaccine.
- The effectiveness of vaccines is often extremely high. The full course of MMR nets a 99.7% immunity (Out of 1000 vaccinated individuals just 3 are not protected). And remember the severity of infection is reduced. So while children vaccinated with the Chicken Pox (Varicella) vaccine may only be protected 80% of the time, there is a net reduction of 100% of moderate and severe cases of Varicella. So while you may get chickenpox you are protected against the severe form of it.
4. Is Natural Immunity better than Artificial Immunity?
- For some diseases, getting the disease provides a longer lasting immune response than gained from vaccination.
- However the entire point is that the disease is itself bad for you. We all remember our bouts with some disease or the other and at no point did we feel happy. We felt run down and miserable and tired. The risks of a disease outweigh the risks of immunisation. For instance? With modern technology, roughly 1 in 6000 cases of Measles ends in Death. (Consider the USA had a million cases of Measles prior to the vaccine and a mortality rate of 1 in 1000 to realise how massive the death toll USED to be).
- Some diseases are patently more lethal and survival of such diseases is rare. Or the diseases in question have a high permanent disability rate or require hospitalisation. For instance Polio, Meningitis (Hib and Meningococcus), Diptheria, Rabies and Tetanus are all incredibly dangerous per infection. While they may be rarer than Measles each infection has a higher mortality rate. In the case of Rabies you may as well take the mortality to be 100%.
- And the entire point of vaccination is to avoid the stress and pain and discomfort and risk of disease not to mention the monetary effects. A sick child will need care either from a parent resulting in a loss of earnings (for many people a week off work is bad…), a loss to the economy, a loss to the child’s education and a drain on health resources if the child requires admission. The vaccine in every case is cheaper.
5. Why are there so many vaccines?
- In most countries there are around about 14 diseases that are vaccinated for. Each of these diseases causes serious illness and death in unvaccinated populations. Even such diseases that we think are harmless such as the mumps have side effects (orchitis and sterility in men).
- Even diseases that have been eliminated from the USA are vaccinated for because of risk of re-infection from a wild state or a carrier.
6. What are boosters and why do we need them?
- A Booster Dose is a successive vaccination over the single original dose.
- We don’t understand why the length of acquired immunity varies with different vaccines. Some work for life and the others require regular “top ups” or “boosters”.
- We are working on it at the moment but for now we honestly do not know why boosters are needed for some vaccines.
7. What is your opinion on Pox Parties? I have heard of Measles Parties too? Is it better than vaccination?
- The idea is that these two diseases are harmless. They aren’t. Measles once killed millions across the planet. Chickenpox used to cause neurological damage and a handful of avoidable deaths. And the entire point of vaccination is to avoid the disease in the first place.
8. Can you get the disease from the vaccine?
- Killed or Antigen vaccines cannot cause the illness
- Live and Attenuated vaccines are theoretically capable of causing the disease particularly to individuals who have weakened immune systems such as cancer patients or AIDS patients. In such cases they are not vaccinated and are protected by the herd immunity.
- Live vaccines provide longer lasting immunity but are harder to store and have can cause infections to the immunocompromised. It’s a calculated decision on which is better to use depending on facilities available.
9 . Can a child’s immune system handle the vaccines?
- Yes. Our immune system fights off threats on greater magnitude and variety than a vaccine.
- The schedules are designed with infant immune systems taken into account and to coincide with when infants are most susceptible certain disease.
- Maternal immunity is temporary and does not provide immunity to every disease. (eg. Hepatitis B)
10 . Why do we vaccinate for the flu every year?
- The flu virus is capable of altering it’s own structure from a variety of different antigens (The H and N – eg. H1N1 indicate Haemagluttinase and Neuraminidase) so the most common antigen varies every year and so we need a different vaccine.
- It’s also why you can catch the Flu over and over again.
- Researchers predict which strain will be most dominant using immunological techniques and produce a vaccine that targets that.
11. Herd Immunity? What is it? How does it work?
- It’s the protection created by the high vaccination rates. If enough people are immunised against a disease the spread of the disease is curtailed by reducing the available targets. This protects those who cannot be vaccinated or are too young from disease.
- It works by disrupting the chain of spread of a disease.
12. Why is allergy to eggs a contraindication to getting some vaccines?
- Some vaccines are cultured in chicken eggs. There is a chance of some egg protein being present in the final product which could trigger an allergic reaction in people allergic to eggs.
- The majority of people who have egg allergies when given a vaccine containing egg protein cultured pathogens such as the Flu vaccine developed minor allergies such as hives which resolved themselves rapidly.
- In most cases, only people with a severe allergy to eggs are recommended against receiving egg-based vaccines.
13. Autism and Vaccines? What’s the story?
- This was a rumour spread after a paper by Andrew Wakefield which has since been thoroughly debunked with a large amount of problems with the original study. The study has been formally withdrawn. In addition there was an alleged link between thiomerosal (a preservative) and autism which was since withdrawn from vaccines. However autism rates have still risen DESPITE the fall in both vaccination rates and elimination of the alleged causes.
- The rumour may exist due to the earliest date for diagnosis of autism being close to the day the MMR booster is given.
14. People say that vaccines are linked to long-term health problems
- Everything you consume has a possible side effect. Even the food you eat. However the majority are mild and temporary. We monitor vaccine adverse effects strictly via a variety of national systems in each country. And there is absolutely no evidence from these to support these claims.
- There is one way that vaccines do contribute to diseases like hypertension, diabetes and cardio-vascular disorders. They increase lifespan significantly and make childhood disorders a non-entity. With more people surviving and living longer diseases of age become more prevalent because you live longer. The life expectancy in Nigeria is 45 years. Diabetes and CHD are less of an issue than say in the UK where our life expectancy is 78. A lot of anti-vax sites show this between different countries without pointing out the reason has more to do with people living a long rather than being more prone to these.
15. Why is vaccination recommended if it can cause all of these side effects?
- You put salt on your food despite it cause high blood pressure, you put sugar in your tea despite it causing diabetes.
- Every vaccine has potential side effects.
- They are usually mild: soreness at the injection site, headaches, and low-grade fevers are examples of common vaccine side effects. Serious side effects are possible, however, including severe allergic reactions. However, the occurrence of these side effects is extremely rare.
- When considering possible side effects from vaccination, it’s important to do so in context. While some possible side effects are serious, they are extremely rare. It’s important to remember is that choosing not to vaccinate also has serious risks. Vaccines protect against potentially fatal infectious diseases; avoiding vaccination raises the risk of contracting those diseases and spreading them to others.
16. Do we do enough safety testing with vaccines?
- Vaccines are tested repeatedly and often to extremely high standards before being approved for general use. I will point out that the naysayers of vaccines often flog alternative medicine which has not been tested or proven to work at a level suitable for animal testing let alone for human use. Vaccines are tested repeatedly before being approved, and continue to be monitored for adverse reactions after their release.
17. Do vaccines contain aborted foetal tissue?
- The Rubella vaccine (German Measles – The R in MMR) is cultured using human cell lines. These were derived from foetal tissue from a variety of sources. Cell lines are grown in labs from the original source and these were derived decades ago (I am unsure of the dates but I know they are at least 40 years old) from cells obtained from legal abortions. The cells that we use are grown in labs and have little to do with foetuses.
18. Did better hygiene and nutrition reduce death and disease rates, rather than vaccines?
- They have reduced some diseases such as xeropthalmia and diarrhoeal deaths. However the vast majority of diseases that we vaccinate for are those spread by routes that exclude the faeco-oral route.
- And “faeco-oral” is a misnomer. It effectively means “touch” and you would be surprised how effective a mode of spread it is. If we glitter your hands you will pretty soon have glitter around your mouth. It’s really that simple to spread a disease by touch alone.
- We look at incidence. Polio used to spread inspite of clean drinking waters and sewers in the USA. There were around a million measles cases a year pre-vaccination and in just 3 years after the vaccine was introduced there were 22,000 cases (roughly). A drop of 98%.
- Every vaccine we look at shows similar traits. We can look at the incidence of disease in India where sanitation hasn’t progressed at the same pace as vaccination. Yet India managed to have two years of no polio cases.
- In western society we can see Chickenpox cases since the vaccine is a new one and the disease incidence plummeted by around 85% in areas where the vaccination has been rolled out.
19. Why can’t we eradicate other diseases, as we did with smallpox?
- We are on the way to eliminate polio. The reason it hasn’t been eliminated is due to an anti-vaccination sentiment in Pakistan, Afghanistan and Nigeria where such sentiment is backed by the guns of local militias such as the Taliban. Many healthcare workers have died trying to eliminate this disease.
- The issue with other diseases is that they possess wild animal reservoirs (they can affect another animals) and so cannot be effectively eliminated.
- Some diseases like tetanus are caused by an opportunistic pathogen that normally lives in soil so is nearly impossible to eliminate from it’s natural habitat.
- Smallpox was easy to eliminate because it was easy to quarantine it’s infected before they became contagious. The other diseases are not so easy.
- We have looked into other diseases that can be eradicated and there are plans to eliminate Polio, Measles, Mumps, Rubella. There are also schemes to eliminate via non-vaccination means the incidence of dracunculosis and filariasis. It is rather amusing that the very disease that is the emblem of medicine (Dracunculosis) is now extinct in the vast majority of the world.
20. Are vaccines linked to HIV?
- In the 1990s various anti-vaccine groups began to blame the testing of a live, weakened polio vaccine in Africa in the 1950s for the spread of acquired immune deficiency syndrome (AIDS). Those idea was that the chimpanzee culture cells used to create the vaccine were contaminated with the SIV (Simian Immunodeficiency Virus) which mutated to become the HIV.
- The accusations, however, were demonstrably false as the vaccine was later tested using a technique that can detect viral DNA (the PCR technique, or polymerase chain reaction); it did not contain SIV or HIV.
- HIV appeared on the scene a fair few decades before the 1950s with earliest date postulated being the 1930s and the oldest being the 1870s. Remember the disease looks like other diseases so it would be hard to detect in an era of relatively poor diagnosis.
21. Is the polio vaccine linked with cancer?
- The first polio vaccines were made by Jonas Salk and Albert Sabin and were made using monkey cells. Years later people found a monkey virus in both vaccines which he called Simian Virus 40 (SV40). Sabin’s OPV contained more virus than the Salk killed vaccine.
- When injected into hamsters, nearly all of them developed massive cancerous tumors. However further testing cleared the issue up.
- First, hamsters that ingested didn’t get cancer. Sabin’s live vaccine was given orally. Additional studies showed that children who were given Sabin’s vaccine did not develop antibodies to SV40; it simply passed through their digestive system, never causing infection.
- That left only Salk’s vaccine, which contained very little SV40, but was given by injection. Studies performed eight years, fifteen years, and thirty years after SV40-contaminated vaccines had been given to children found that they had the same cancer incidence as unvaccinated groups. No credible evidence suggests that SV40 has ever caused cancer in humans.
Any other questions? I can eventually add them to Part 4… Ask away in the comments.