The discovery of a new variant of the coronaviruses caused global panic. The variant has already been detected in at least 23 countries, including the U.S., and countries quickly imposed travel bans and closed their borders.
The new variant has more than 30 changes to its spike protein, which is one of the reasons for the knee-jerk reactions. The target of most vaccines is thisProtein, which allows the virus to take over human cells. The virus is more likely to evade the immune system and vaccines when there are Spike protein changes in previous versions. It's not clear if Omicron causes more disease than previous versions, or if it will make the vaccines less effective. A new pre-print study by South African scientists suggests that Omicron is three times more likely to cause harm.
Scientists are trying to understand how so many different types of mutations came about in a short time.
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The Oswaldo Cruz Institute in Rio de Janeiro has a researcher who is interested in how rapid evolution occurred. The rise of the Gamma variant in Brazil in November 2020 was tracked by a team of people. With Gamma, we realized that there were different types of mutations in different individuals. Some individuals had some changes but not others. He says that the rise of Gamma was a process that happened in a population of individuals.
One possibility is that the Omicron variant could have arisen if it had spread to an isolated group of people. It could have been introduced into the larger population, where it could travel into different groups and countries.
The virus may have changed in a single person before finding a new home. Anna-Lise Williamson, chair in vaccineology at the University of Cape Town, and Ed Rybicki, director of the university's biopharming research unit, wrote in response to a letter that this could happen in an immune-suppressed person. More than seven million people in South Africa are HIV positive. Many countries have HIV infections. Some scientists theorize that Omicron arose in Southern Africa because it was first identified there, but older cases have since been identified in European countries and the U.S.
The CD4+ T cells in healthy people are stimulated by the killer T cells. The killer T cells destroy the cells that have been bitten by the virus. In people with low numbers of CD4+ T cells, the virus establishes a persistent infection because of a lack of killer-T-cell responses. Their immune systems produce some immune cells called B cells that cause an arms race between the virus and the antibodies, according to the authors. The weak B-cell response causes the genetic sequence for the virus's spike protein to be changed to escape the antibodies.
There is evidence to support this idea. A woman with HIV was described in a preprint study as having an infectious disease for more than six months. Some of the virus's mutations were on the spike protein.
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It is possible that the virus spilled back into an animal's body before it re-invade humans. There have been many cases of other wild and domesticated mammals contracting the virus, which is believed to have arisen in a bat. There was a confirmed case of the mink infecting a farm worker in the Netherlands last year, as well as reports of an outbreak of coronaviruses on farms in North America and Europe.
Omicron may have jumped from animals to humans. He says that in another species, the virus could accumulate some mutations very quickly. At this point, the idea is mostly speculative.
It is important to understand where Omicron came from to determine the earliest patient or community in which it spread. Akiko Iwasaki, a professor of immunology and cellular and developmental biology at Yale University, says it is difficult to identify a patient with a variant. She says that the viruses surveillance efforts only capture a fraction of the people who are infectious. Iwasaki says that it may be possible to identify a general geographic area and an approximate time when the virus changed into Omicron.
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Omicron is a wake-up call about vaccine inequity and the need for greater access, according to Michael Head, a senior research fellow in global health. Only 6 percent of people in low-income countries have received at least one dose of vaccinations, according to Oxford University. The African Centers for Disease Control and Prevention says that African countries have given more than 200 million vaccines.
Head says that the main variant that caused concern so far has emerged from an outbreak in unvaccinated populations. That is where COVID thrives the best and where the virus has the greatest chance to change. If the vaccine can keep the outbreak under control, you reduce the opportunities.
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The World Health Organization's Director-General Tedros Adhanom Ghebreyesus said on November 28 that the Omicron variant reflects the threat of vaccine injustice. The longer we take to deliverVaccineEquity, the more we allow the #COVID19 virus to circulate and become potentially more dangerous.
