Re: Intramuscular, not intravenous 5 March 2005
Dr Viera Scheibner,
Principle Research Scientist (Retired)
Blackheath, NSW 2785 Australia

I have been following the polemic about whether vaccines are injected into the blood stream or not with great interest.

To take everybody out of their misery, according to Taberís Cyclopedic Medical Dictionary (14th Edition, 1981):

Blood vessels = The veins, arteries and capillaries.

Blood stream = The blood which flows through the circulatory system of an organism.

Circulatory system = The cardiovascular system consisting of the heart and the blood vessels (arteries, arterioles, capillaries, venules, veins, and sinuses) and the lymphatic system.

Lymphatic system = That system including all structures involved in the conveyance of lymph from the tissues to the blood stream. It includes the lymph capillaries, lacteals, lymph nodes, lymph vessels, and main lymph duets (thoracic and right lymphatic duct)

Lymphatic vessels = Thin-walled vessels conveying lymph from the tissues. They resemble veins in structure, possessing three layers: the intima, media, and adventitia. They possess paired valves.

The vaccines contents, whether injected into the muscles or subcutaneously, are picked up by the capillaries which carry the material into the larger blood vessels of the circulatory system and even into the lymphatic system. So, the contents of vaccines are introduced into the blood stream and the lymphatic system.

If in doubt, look it up in a dictionary.

Competing interests: None declared