Juan C. Ravell, M. Prior to authorization by the FDA, these vaccines underwent the same rigorous safety and effectiveness standards as all other vaccines. Quickly, vaccine distribution began, starting with health care professionals on the frontlines of patient care.
Some rumors even suggested that the vaccines contain gluten, wheat, eggs and even bee venom! All of that is simply, untrue. People may think of formaldehyde as a man-made chemical, but in small quantities it is also found naturally in the bloodstream.
All vaccine ingredients are present in very small quantities, and there is no evidence that they cause harm in these amounts. The exception to this is the small number of people who may be severely allergic to a vaccine ingredient, even if it is present only in trace amounts for example, egg proteins or antibiotics used in vaccine manufacture.
If you look up some vaccine ingredients on the internet you may read that they could be harmful, but most of them are present in vaccines in amounts that are completely normal for our bodies. Even common salt sodium chloride , which is essential for normal functioning of the body, is harmful in large quantities.
For further information about vaccine ingredients, contact the manufacturer of the vaccine. They challenge the immune system so that it makes antibodies to fight the disease see our animation on 'How do vaccines work?
Vaccines contain tiny quantities of active ingredients — just a few micrograms millionths of a gram per vaccine. To give some idea of how small these quantities are, one paracetamol tablet contains milligrams of the drug. This is several thousand times more than the quantity of the active ingredient you would find in most vaccines.
Hundreds of thousands of individual vaccines could be made from a single teaspoon of active ingredient. Some vaccines contain whole bacteria or viruses. In these cases the bacteria or viruses will either be severely weakened attenuated so that they cannot cause disease in healthy people, or killed altogether inactivated.
Many vaccines contain only parts of viruses or bacteria, usually proteins or sugars from the surface. These stimulate the immune system but cannot cause disease. See our page on 'Types of vaccine'. Compared with the number of viruses and bacteria in the environment that our bodies have to deal with every day, the amount of active ingredient in a vaccine is very small indeed. Most bacterial vaccines contain just a few proteins or sugars from the relevant bacterium. By contrast it is estimated that trillion bacteria live on the skin of the average human being, each of them containing many thousands of proteins which constantly challenge our immune systems.
These are products such as aluminium salts that help to improve the immune response to vaccines, or products that act as preservatives and stabilisers for example, gelatine or human serum albumin. Like vaccines, most of the medicines we use also contain excipients. Many vaccines contain aluminium salts such as aluminium hydroxide, aluminium phosphate or potassium aluminium sulphate.
They act as adjuvants, strengthening and lengthening the immune response to the vaccine. Aluminium salts appear to slow down the release of the active ingredient from the vaccine once it is injected, and stimulate the immune system to respond to the vaccine.
They also absorb protein well, and stop the proteins in the vaccine sticking to the walls of a container during storage. It reacts with other elements to form aluminium salts, and small amounts of these are found naturally in almost all foods and drinking water, as well as in breast milk and in formula milk for babies.
Aluminium salts are used as food additives for example in bread and cakes and in drugs such as antacids, and aluminium is widely used in food packaging. Aluminium is not used by the body.
Any aluminium absorbed from food or other sources is gradually eliminated through the kidneys. Over time, small amounts of the aluminium from food, drink and other sources do accumulate in the body, but this is not believed to pose a significant risk to health see for example this UK research from The amount of aluminium present in vaccines is small - less than 2 milligrams of the salts, and less than a milligram of actual aluminium.
In the UK, the highest dose of aluminium that babies receive in one go from vaccines is just under 1. A study from modelled the impact of aluminium from diet and vaccines in infants, and concluded that the total amount of aluminium absorbed from both sources was likely to be less than the weekly safe intake level.
A study from drew similar conclusions. A study published in March took samples of blood and hair from 85 babies and measured their levels of aluminium. These levels varied considerably, but researchers did not find any correlation between aluminium levels in blood or hair and the estimated amount of aluminium that the babies had received from vaccines.
Vaccines that contain aluminium are associated with more redness and hardness at the injection site than other vaccines. Rarely, aluminium adjuvants may cause small itchy lumps granulomas to form at the injection site. A Swedish study found that this happened in a small number of children fewer than 1 in after vaccination with the 5-in-1 vaccine Infanrix and pneumococcal vaccine Prevenar.
Granulomas are not dangerous but can be irritating and last for months or even years. The study found that children with granulomas often developed an aluminium contact allergy. However, most children recovered from their symptoms. Aluminium salts are found in these vaccines used routinely in the UK.
The exact amounts of aluminium per dose are listed for each vaccine:. MF59 is used in only one vaccine licensed in the UK: Fluad, a flu vaccine introduced in the flu season for adults aged 65 and older see the page on the Inactivated Flu Vaccine. Fluad is not a new vaccine; it was first licensed in and millions of doses have been given worldwide. MF59 is added to the vaccine to make it more effective.
It is an adjuvant which helps to strengthen and lengthen the immune response to the vaccine. It may also lead to an increase in common side effects such as pain, swelling or redness at the injection site, slightly high temperature, headache, feeling generally unwell, shivering, or tiredness.
However, there is no evidence that MF59 causes more serious adverse effects. The main ingredient in MF59 is squalene oil, a naturally-occurring oil found in humans, plants and animals. The squalene oil in MF59 comes from fish oil and is highly purified before it is used. Fluad contains less than 10mg of squalene 1mg is one thousandth of a gram.
MF59 also contains very small amounts of these ingredients around 1mg or less :. Thiomersal is a mercury-based preservative used in tiny quantities in some vaccines to prevent the growth of bacteria and fungi which can contaminate from the environment when the vaccine is opened. Most single-dose vaccines do not contain thiomersal because they are used only once and so there is very little risk of contamination. However, some vaccines are produced in multi-dose vials. There are two reasons for this: they are cheaper, and they are easier to produce quickly in large quantities in the event of an epidemic.
Tiny quantities of thiomersal are often used in multi-dose vaccines to stop them becoming contaminated once they are opened. Thiomersal was removed from UK vaccines between and , and is no longer found in any of the childhood or adult vaccines routinely used in the UK. Before , thiomersal was present in diphtheria- and tetanus-containing vaccines, as well as hepatitis B vaccine and some flu vaccines.
However, it is not present in any of the annual flu vaccines currently in use in the UK. This was in line with the global goal of reducing environmental exposure to mercury from all sources. However, there was no evidence that thiomersal in vaccines caused harm. Thiomersal contains a compound called ethyl mercury, but concern about mercury in the environment has centred on a different compound called methyl mercury, which accumulates in the food chain and in the human body.
A study from showed that the ethyl mercury in thiomersal does not appear to accumulate in the bodies of even very small babies.
There is also detailed information about the safety of thiomersal on the US Food and Drug Administration's pages. A Australian study of over a million children found no evidence of a link between thiomersal in vaccines and autism development. Gelatine derived from pigs is used in some live vaccines as a stabiliser to protect live viruses against the effects of temperature.
Gelatine in vaccines is highly purified and hydrolysed broken down by water , so it is different from the natural gelatine used in foods. For example, very sensitive scientific tests have shown that no DNA from pigs can be detected in the nasal flu vaccine Fluenz. There have been a tiny number of cases of allergic reaction to vaccines containing gelatine about one case for every 2 million doses of vaccine. People with a known allergy to gelatine should seek expert advice before receiving vaccines containing gelatine.
Members of Muslim or Jewish religious communities may be concerned about using vaccines that contain gelatine from pigs porcine gelatine. Nonetheless, several public health agencies and vaccine manufacturers agreed in to cease using thimerosal as a precautionary measure. Today, no vaccine contains Thimerosal except the influenza vaccine, and Thimerosal-free alternatives are available.
Formaldehyde Why is it used? Formaldehyde has been used for decades in vaccines to inactivate viruses and detoxify bacterial toxins, ensuring they don't result in sickness when injected. The U. Additionally, several studies have since linked strong, long-term formaldehyde exposure to certain types of cancer. The potential for harm depends on the amount. Formaldehyde is always present in the human body as part of our natural metabolic process, but long-term exposure to high amounts can overwhelm our system and be harmful.
Fortunately, the amount of formaldehyde found in vaccines is very small, most of it being diluted down to residual amounts during the manufacturing process. In fact, the FDA reports there is 50 to 70 times more formaldehyde present in an average newborn's body than in a single dose of vaccine. In brief, current science shows formaldehyde in vaccines to be harmless.
The highest amount of formaldehyde present in any vaccine is. An average two-month-old baby would have around 1.
Aluminum Why is it used? Aluminum is used as an adjuvant in vaccines. That is, it makes them more effective by strengthening the immune system response. Thanks to adjuvants, people need fewer doses of vaccine to build immunity.
Sometimes the mention of aluminum in vaccines makes parents uneasy; that's because there has been some evidence that long-term exposure to high amounts of aluminum can contribute to brain and bone disease.
However, aluminum is naturally present in water, foods, even breast milk. Aluminum has only been shown to harm people if absorbed in very high amounts and when a person's kidneys aren't working properly.
In contrast, the amount of aluminum in vaccines is negligible. Aluminum is the third most common naturally-occurring element, after oxygen and silicon. It is found in plants, soil, air, and water.
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