COVID-19 Update: New Coronavirus Variant and Herd Immunity
The coronavirus pandemic, now more than 10 months old, shows no sign of abating, even as vaccines are slowly rolling out. In early January, the U.S. set single day records for deaths and new diagnoses for COVID-19, the condition caused by the virus.
New COVID Strains
Meanwhile, the virus is evolving. A new strain, SARS-CoV VOC 202012/01 (or B117), a mutation of the original virus that was reported in England in September, has now spread to more than 30 countries, including the U.S. The new strain is more communicable than SARS-CoV-2, the original virus, scientists think. Fortunately, it does not appear to make people sicker. Meanwhile, another strain -- 501Y.V2 -- was identified in South Africa.
Unfortunately, viruses can adapt to their host or environment. The speed in which they mutate their genes is often based on the type of virus. Fortunately, scientists think COVID-19 is changing much slower as it spreads.
The genetic mutations to the original COVID-19 affected the spike proteins that cover the outer coating of the virus, causing them to adhere better to cells, particularly in the nose, raising the level of contagiousness. Some medical experts think the 501Y.V2 has a higher viral load, also making it more contagious. Like the original strain, the new strains cause severe disease and symptoms include:
- Fever or chills
- Cough, shortness of breath, difficulty breathing
- Muscle soreness, body aches, headache
- Sore throat, runny nose, congestion
- Gastrointestinal upset
- New loss of taste or smell
Recovery from the newer strains is expected to be the same as the original strain. Most people feel much better within a few weeks, but symptoms such as fatigue, shortness of breath, cough, joint pain and chest pain can linger. There’s also a higher risk for developing mental health issues. Olfactory dysfunction (or loss of smell), which appears in 86 percent COVID-19 cases, can take up to six months to disappear, according to a study published in the Journal of Internal Medicine.
As of now, scientists believe the vaccine will work on the new strains. And don’t believe new precautions are necessary. Continue to social distance, wear a mask in public, wash your hands regularly, maintain your immune system, disinfect regularly used items and surfaces and work with your MDVIP-affiliated doctor to manage chronic conditions.
Herd Immunity
Herd immunity occurs when enough people in a community become immune to a specific virus, lowering the risk of it spreading. We’ve achieved herd immunity against measles, mumps, chickenpox and polio and partial herd immunity to Spanish flu (H1N1). Can we do it with COVID-19?
Unfortunately, no one knows yet. With some viruses, a high infection rate is all you need to obtain herd immunity. People get infected, develop antibodies, become immune from it and that immunity helps slow the transmission rate.
Other viruses require help for a country to achieve herd immunity – that’s where vaccines come in. Vaccines train our immune systems to fight specific viruses. Once you’ve been vaccinated, you’re protected from getting the virus and passing it on to others for a period of time – ranging from life to a few years, typically. But that’s only personal immunity. You can’t achieve herd immunity until a very large percentage of a population gets vaccinated. For example, herd immunity from measles requires a 95 percent vaccinate rate; polio is about 80 percent, according to the World Health Organization.
Scientists don’t know the percentage needed for COVID-19 herd immunity. Estimates by health officials range from 60 percent to 85 percent. But there seems little dispute that as many Americans as possible as possible need to get vaccinated before we can hope to achieve herd immunity.