WHAT IS MYOCARDITIS?
Myocarditis is an inflammation of the heart
muscle (myocardium). Infection with a virus usually causes myocarditis.
Sometimes myocarditis
can result from a reaction to a drug (including some antibiotics) or be part of a more general
inflammatory condition such as Lupus. Severe myocarditis can cause cardiac arrhythmias and can lead to heart failure if it weakens your heart so that
the rest of your body
doesn't get enough blood. Clots can form in your heart, leading to a
stroke or heart attack.
Symptoms of myocarditis include fatigue, shortness of breath, chest pain, edema (fluid buildup) in the legs and feet, and cardiac symptoms such as tachycardia (rapid heartbeat) and arrhythmia (abnormal heart rhythm). Because myocarditis is often caused by a virus, the person may also have typical viral symptoms such as fever and joint pain. Myocarditis can be caused by a wide variety of pathogens including bacteria, viruses, parasites, and fungi. Herpes viruses such as Epstein-Barr (HHV-5) and Herpes Simplex (aka cold sores, also know as HHV-1) are common viral causes, as are cold viruses and echoviruses (GI infections often called "stomach flu"). The most common bacterial causes are streptococcus, staphylococcus, and the bacteria associated with Lyme Disease. Other infections that can be responsible include toxoplasma gondii (the parasite associated with cat feces), histoplasma (a fungus associated with bird and bat droppings), yeast (candida) and mold such as aspergillus.
WHAT IS PERICARDITIS?
Pericarditis is swelling and irritation of the pericardium, which is a thin layer of tissue
surrounding your heart. Pericarditis often causes sharp
chest pain that occurs when the
irritated layers of the pericardium rub against each other, but can also cause dull aching pain. The pain usually occurs on the left side of your chest and can radiate down your left arm and up along your neck into your jaw. Other symptoms can include shortness of breath (especially when lying down), palpitations, fever, edema in the legs, feelings of weakness and fatigue, and cough. Pericarditis can have a fast onset and only last a short time, or it can come on slowly and become chronic.
New MMWR CDC study compares covid myocarditis to vax myocarditis | Is it good science?
This study by the CDC claims that the rate of myocarditis is much higher after a SARS CoV2 infection than it is after vaccination. Dr Prasad says that this is not the real question, the real question is how many doses of vaccine are best for someone who has already had COVID 19 vs someone who has not. There has been a claim that is circulating that says that myocarditis after infection is always worse than it is after vaccination, but is this true? This paper significantly underestimates the number of people who've had COVID 19 infection but not a vaccine. It is capturing only those people whose infections were serious enough for them to be tested in a hospital but not those who tested at home or simply didn't test. It's known that many Americans didn't get testing from a hospital, probably the milder cases, so this paper seems to be biased by only counting the COVID 19 infections that were worse and more dangerous. Also, the rate of Myocarditis after vaccination is consistent with findings in other countries, but the rate after COVID 19 is 50 times higher than the rate found in the UK in a high quality study. The study uses billing claims coding as an indicator of myocarditis but this is also problematic. People sick enough with SARS CoV2 to be hospitalized are more likely to be tested for myocarditis, and be coded that way, so it is likely to pick up on other things that could have received a billing code of myocarditis.
Myocarditis and Pericarditis After Vaccination for COVID-19
