When muscles repeatedly contract and relax, they produce rhythmic, involuntary shaking movements called tremors. Almost everyone has physiologic tremors but in some people these can be too slight or mild and not easily noticed.
Tremors that occur when muscles are active are called action tremors. Resting tremors occur when muscles are at rest, making an arm or a leg shake even when one is completely relaxed. Parkinson’s disease tremors are an example.
Intention tremors occur when a person purposely makes a movement. These may occur in persons with disease of the cerebellum (located at the base of the brain), multiple sclerosis, or stroke. These tremors, slow and coarse, may also occur at rest and can increase with activity.
Essential tremors, the exact cause of which is unknown, usually begin in early adulthood. When they occur in families they are sometimes called familial tremors. These are fine, fast tremors that slowly become more obvious as the person grows old. The tremors can cause inconvenience as they may affect daily tasks like handling instruments and utensils. One or both sides of the body may be involved, and head bobbing can occur. The tremors can be made more obvious by caffeine, stimulants, stress, tiredness, and some drugs like theophylline. When these tremors develop later in life, they are called senile tremors.
Myoclonic jerks are short and fleeting bursts of muscular excitation involving most muscles at once, like when a person first falls asleep. The myoclonus may involve muscles in an upper leg, in an arm, or in the face. Sudden brain hypoxia (decreased blood flow to the brain), epilepsy, or degenerative changes brought about by diseases associated with aging may cause multifocal myoclonic jerks.
Muscle cramps are sudden, brief, painful contraction of a muscle or group of muscles and may be due to low blood flow and oxygenation of the muscle/s involved. These can occur after exercise or while sleeping. Positional change and muscle stretching before sleeping or before exercising can help prevent cramps which are basically harmless and do not need treatment.
Persistent and worsening tremors or other movement disorders that affect one’s quality of life and daily activities warrant consult with a physician. Any underlying disease should be excluded, like hyperthyroidism and diseases of the nervous system.
The Centers for Disease Control and Prevention posted the following on its website on April 5, 2021, which can have an impact on future guidelines on disinfection and infection control policies:
“People can be infected with SARS-CoV-2 through contact with surfaces. However, based on available epidemiological data and studies of environmental transmission factors, surface transmission is not the main route by which SARS-CoV-2 spreads, and the risk is considered to be low. The principal mode by which people are infected with SARS-CoV-2 is through exposure to respiratory droplets carrying infectious virus. In most situations, cleaning surfaces using soap or detergent, and not disinfecting, is enough to reduce risk. Disinfection is recommended in indoor community settings where there has been a suspected or confirmed case of Covid-19 within the last 24 hours. The risk of fomite transmission can be reduced by wearing masks consistently and correctly, practicing hand hygiene, cleaning, and taking other measures to maintain healthy facilities.”
