What Is A Variant?
How do variants occur?
| Download this episode | The term “variant” is used quite a bit these days in the news, thanks to the COVID-19 pandemic, but what exactly is a variant and how do they occur? When viruses spread, they make copies of themselves. As they do, they often mutate, or change. A copy that is different from the original virus is called a variant. Some variants don’t seem that different from the original virus. Others may have clear differences. The coronavirus that causes COVID-19 has gone through this type of changing process many thousands of times during the pandemic. Each time a new coronavirus variant emerges, the World Health Organization gives it a name based on a letter from the Greek alphabet. Variants of note include alpha, delta, and omicron. Variants can differ from the original virus based on how contagious they are, how sick they make people, how they respond to vaccines and medicines and whether people can get infected with the virus more than once. | Coronavirus variants are placed in categories by organizations such as the World Health Organization. A variant of interest is a coronavirus variant that, compared to earlier forms of the virus, has genetic characteristics that predict greater transmissibility, evasion of immunity or diagnostic testing tools or the potential to cause more severe disease. A variant of concern is one which has been observed to be more infectious, more likely to cause breakthrough or re-infections in those who are vaccinated or previously infected. These variants are more likely to evade diagnostic tests or resist antiviral treatment. Alpha, beta, gamma, and delta variants of the COVID-19 coronavirus are classified as variants of concern. A variant of high consequence is a variant for which current vaccines do not offer protection. Fortunately, there are no COVID-19 variants YET which have met the criteria to be assigned to the high consequence category. | The delta variant of the COVID-19 coronavirus began attracting attention last summer when a significant increase in new cases reversed what had been a steady decline since January 2021. The delta variant is highly contagious, more than two times as contagious as previous variants. The symptoms of the variant were like those caused by the original version of COVID-19. However, physicians are seeing people getting sicker quicker, especially for younger people. Research demonstrated that the delta variant grew more rapidly, and to much greater levels, in the respiratory tract. Typically, vaccinated people had no symptoms or very mild symptoms if infected with the delta variant. Their symptoms were more like those of a common cold, such as cough, fever or headache, with the addition of a significant loss of smell. Fortunately, all three of the FDA-authorized COVID-19 vaccines protected most very well from the delta variant. | Since December 2021, the omicron variant has taken over as the main mutation of COVID-19. The omicron variant is MUCH more contagious than any other strain identified to date, Fortunately, it’s generally causing less severe symptoms than the delta variant. According to the Centers for Disease Control, people can catch and spread omicron even if they’re vaccinated or don’t have symptoms. All the variants, including omicron, cause similar respiratory symptoms, including cough, fever and fatigue. There is some evidence that fewer people with omicron lose their taste and smell. While omicron has caused more disease more rapidly than any other variant, it is less likely to cause severe disease such as pneumonia that may require treatment in the hospital. In fully vaccinated and boosted people, omicron symptoms tend to be milder. In unvaccinated people, the symptoms may be severe, leading to many hospitalizations and deaths. | If you test positive for COVID-19, how can you tell which variant you are infected with? According to Dr. Robert Hopkins, director of the Division of General Internal Medicine at UAMS, the only way to know which variant causes a person’s infection is to perform a genetic sequence of the virus. Selected samples from persons with a positive PCR, or polymerase chain reaction, test go to labs like the Centers for Disease Control and Prevention. The process can take up to several weeks, but these results help public health officials track the spread and mutation of the coronavirus. Most PCR tests base their results on the detection of three signals or genes from the virus RNA. A signal from at least two of the three genes means the sample is positive for COVID-19. When it comes to ANY variant of COVID-19 to date, Dr. Hopkins says being vaccinated is still the most effective way to prevent hospitalization and serious illness or death.
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Categories for variants
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The delta variant
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The omicron variant
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Which variant do you have?
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