COVID-19 Disease

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Last reviewed
September 13, 2021

COVID-19 Disease 

Since 2019, the US Centers for Disease Control and Prevention (CDC) and the World Health Organization (WHO) have been closely monitoring the worldwide outbreak of a novel beta coronavirus known as SARS-CoV-2, which is causing the coronavirus disease 2019 (COVID-19) in humans.

The U.S. CDC reported about 80% of COVID-19 deaths occurred in people over age 65.

Among 378,048 death certificates listing COVID-19 in 2020, 97% had a co-occurring diagnosis of a plausible chain-of-event condition (e.g., pneumonia or respiratory failure) or a significant contributing condition, hypertension, diabetes, or both.

A meta-analysis published on April 27, 2021, based on 22 studies conducted by researchers at the German Diabetes Center, found men with diabetes were 28% more likely to die from COVID-19 than diabetic women were, and people with diabetes aged over 65 with diabetes were more than three times more likely to die than younger patients were.

On April 28, 2021, The Lancet published a study that found an association between body-mass index and COVID-19 severity. At a BMI of more than 23 kg/m2, these researchers found a linear increase in the risk of severe COVID-19 leading to admission to hospital and death and a linear increase in admission to an ICU across the whole BMI range, which is not attributable to excess risks of related diseases.

COVID-19 Reinfection Immunity

On January 26, 2021, 'the immune systems of more than 95% of people who recovered from COVID-19 had durable memories of the virus up to eight months after infection. The study's results circulating antibody titers were not predictive of T cell memory. Thus, simple serological tests for SARS-CoV-2 antibodies do not reflect the richness and durability of immune memory to SARS-CoV-2.'

An updated listing of immunity studies is published at this link.

COVID-19 Disease Symptoms

The CDC announced on March 3, 2020, that a significant portion of individuals infected with the SARS-CoV-2 coronavirus lack symptoms (“asymptomatic”) and that even those who eventually develop symptoms (“pre-symptomatic”) can transmit the virus to others for several days before showing symptoms. People with COVID-19 have reported a wide range of symptoms that may appear 2-14 days after exposure to the SARS-CoV-2 virus.

A study published by The Lancet on November 3, 2020, confirmed that anosmia is the single most predictive symptom of a positive swab test across different age groups, with odds ratios ranging from 13.67 (95% CI 11·65–16·02) for the older group to 20.86 (18·62–23·4) for the younger group.

On September 2, 2021, the findings of a cross-sectional study published by The Lancet suggest that differences in symptoms occurring with new loss of taste or smell were seen between groups based on SARS-CoV-2 test positivity. Muscle aches, mild difficulty breathing, vomiting, diarrhea, and congestion were associated with a new loss of taste or smell in both groups. 

People at Risk from COVID-19 Disease

COVID-19 is a new disease, and scientists are still learning how it spreads. However, data published by the U.S. CDC indicates people can catch the COVID-19 disease from others who have the SARS-CoV-2 virus. In addition, older people, and those with underlying medical problems such as obesity, high blood pressure, heart problems, or diabetes, are more likely to develop serious illnesses.

As of January 31, 2021, the CDC confirmed that most adults hospitalized for COVID-19 were older, obese, and had comorbidities such as hypertension, cardiovascular, and metabolic diseases. 

On March 8, 2021, and October 6, 2020, the CDC stated, 'Obesity increases the risk for severe COVID-19–associated illness. In addition, obesity was a risk factor for hospitalization and death, particularly among adults aged <65 years. These findings highlight clinical and public health implications of higher BMIs, including the need for intensive management of COVID-19–associated illness, continued vaccine prioritization and masking, and policies to support healthy behaviors.'

On August 31, 2021, the U.S. CDC reported during March 2020–January 2021, patients with COVID-19 had nearly 16 times the risk for myocarditis, an inflammation of the heart muscle, and risk varied by sex and age.

COVID-19 Disease Diagnosis

COVID-19 disease is diagnosed by a healthcare provider when a sample is tested via reverse transcription-polymerase chain reaction (RT-PCR) to determine the presence of viral RNA.

COVID-19 Preventive Vaccines

The COVID-19 vaccine development landscape includes various innovative platforms, says the U.S. FDA. To review a listing of experimental COVID-19 vaccines worldwide, please visit this CoronavirusToday webpage.

Coronavirus FAQs

Note: Content sourced from the CDC, WHO, various governments, news agencies, social media networks, and the Precision Vax news network. All of the posts have been review by medical professionals, such as Dr. Robert Carlson.