The most common variant of the coronavirus so far is threatening a new wave of infections in the United States, even among those who have recently recovered from the virus.
A sub-variant of Omicron, known as BA.5, is now dominant and, along with another sub-variant, BA.4, is contributing to the outbreak of cases and hospitalizations, according to federal estimates released Tuesday.
Estimate the proportion of cases from Omicron variants
Sources: CoVariants.org; GIRLS; New York Times Case and Death Database | Note. Charts show 14-day averages of cases and frequency of variants between cases is estimated. Sequence rates may reflect localized trends based on testing in a particular region or hospital. Charts represent the latest data available, which may be out of date and subject to change as additional series are completed. Recent data is based on the smallest samples and is especially likely to change.
Although the popularity of home tests means that reported cases are a significant understatement of the true infection rate, the proportion of positive tests is on the rise and is now higher than during most other pandemic waves. According to the CDC, the risk of Covid-19 is increasing in much of the country.
“I think there’s an underestimation of what it’s doing to the country, and it’s already having an impact,” said Eric Topol, a professor of molecular medicine at Scripps Research who has written about the subversion.
BA.5 and BA.4, both sub-variants of the Omicron variant that took over the world over the winter, are the most capable versions of the virus yet to evade immunity from previous infections and vaccines. Both variants have mutations in their proteins that differ enough from earlier versions of the virus that they can evade certain antibodies.
Waves of infection – and accompanying immunity – vary from country to country and make for imperfect comparisons. Vaccination rates also vary. However, in places where BA.4 and BA.5 have dominated for weeks or months, sub-variants have caused an increase in cases and hospitalizations, despite some immunity of the population to previous waves.
Covid-19 hospitalizations per 100,000 people
Sources: Our World in Data, CoVariants.org, Centers for Disease Control and Prevention, US Department of Health and Human Services. | Note. The time periods at which BA.4 and BA.5 become dominant are estimates.
C.D.C. says there is no evidence so far that BA.4 or BA.5 are inherently more severe than other Omicron sub-variants, but if more people become infected, the number of people hospitalized with the virus could also rise.
Dr. Topol said that prior infection with another form of the Omicron variant confers some degree of immunity and may explain why cases have not yet spread dramatically in the United States. “But it’s nothing like we hoped for,” he said. The Omicron subvariants appear to represent a departure from earlier waves of the virus, when prior infection was more likely to protect against reinfection.
Portugal, which has a higher vaccination rate than the US, saw a sharp increase in cases after BA.5 became dominant in May and hospitalizations approached their previous Omicron peak.
Estimate the proportion of cases from Omicron variants
Sources: CoVariants.org; GIRLS; New York Times Case and Death Database | Note. Plots show 14-day case averages, and variant frequencies are CoVariance estimates binned over two-week intervals. The ranking may reflect localized trends based on testing in a particular region or hospital. Charts represent the latest data available, which may be out of date and subject to change as additional series are completed. The latest data is based on the smallest samples and is especially likely to change.
Before BA.4 and BA.5 became dominant in South Africa in April, studies showed that 98 percent of the population had antibodies from vaccination or previous infection, or both.
Even with these protective antibodies, many people in the country were still infected with BA.4 and BA.5, and the sub-variants caused a small increase in cases, hospitalizations and deaths.
Estimate the proportion of cases from Omicron variants
Sources: CoVariants.org; GIRLS; New York Times Case and Death Database | Note. Plots show 14-day case averages, and variant frequencies are CoVariance estimates binned over two-week intervals. Sequence rates may reflect localized trends based on testing in a particular region or hospital. Charts represent the latest data available, which may be out of date and subject to change as additional series are completed. Recent data is based on the smallest samples and is especially likely to change.
You can’t save places that are just emerging from significant spring waves either. Several European countries experienced large outbreaks of Omicron’s different sub-variant, BA.2, leading to new waves of hospitalizations and deaths that only peaked in April. However, cases are on the rise again in these countries as BA.5 becomes dominant.
Estimate the proportion of cases from Omicron variants
Estimate the proportion of cases from Omicron variants
Estimate the proportion of cases from Omicron variants
Sources: CoVariants.org; GIRLS; New York Times Case and Death Database | Note. Plots show 14-day case averages, and variant frequencies are CoVariance estimates binned over two-week intervals. Sequence rates vary by country and sometimes reflect local trends based on testing in a particular region or hospital. Charts represent the latest data available, which may be out of date and subject to change as additional series are completed. Recent data is based on the smallest samples and is especially likely to change.
Experts say it is too early to fully predict what the latest sub-variants might bring to the US, which saw an even more recent wave of viruses in May and June, fueled by both BA.2 and another sub-variant called BA.2.12.1. The high proportion of recent BA.2.12.1 infections, as in the United States, was unusual among countries currently experiencing waves of BA.4 and BA.5 infections.
The US also has a lower vaccination rate than many of these countries and a much lower proportion of the elderly who have received one or both booster shots.
“There’s a wave, there’s no doubt about it,” Dr. Topol said. “My concern is the length of it.”
Tracking the Coronavirus
What is the difference between people who have asymptomatic or pre-symptomatic COVID-19?
Both terms refer to people who have no symptoms. This may interest you : Tarrant County Public Health reports one death from COVID-19. The difference is that “asymptomatic” refers to people who are infected but never develop any symptoms, while “symptomatic” refers to infected people who have not yet developed symptoms but develop symptoms later.
Can you be contagious before showing symptoms of COVID-19? “A person with COVID-19 is considered contagious starting two days before symptoms develop, or two days before the date of a positive test if asymptomatic,” the CDC states.
How long after COVID-19 exposure could you be contagious?
Evidence shows that most of the spread of COVID-19 occurs closer to the onset of symptoms, usually 1-2 days before and 2-3 days after symptoms appear. However, transmission is still possible up to 10 days after infection.
What is the difference between presymptomatic and asymptomatic cases of COVID-19?
A presymptomatic case of COVID-19 is a person infected with SARS-CoV-2 who has not yet developed symptoms at the time of testing but develops symptoms later in the course of infection. An asymptomatic case is a person infected with SARS. On the same subject : Environmental Findings, Risk Factors of Atopic Dermatitis in School Children. CoV-2 who do not show symptoms at any time during the infection.
What are some symptoms of the COVID-19 BA.4 and BA.5 Omicron subvariant?
Experts say most of the symptoms of the recent sub-variant are the same as other strains of COVID, including stuffy nose, body aches, sore throat, sneezing, headache, cough, fatigue and more. On the same subject : WHO: Monkey pox is not yet a global health emergency.
Can you get the Omicron variant of COVID-19 twice? Long story short, laboratory data suggest that prior infection with the original omicron does little to protect against re-infection with the new mutants, although the actual risk of re-infection, regardless of variant, is unique to each person and situation.
What are some symptoms of the COVID-19 BA.4 and BA.5 variant?
People infected with BA.4 and BA.5 may experience cough, runny nose, sore throat, fatigue, headaches and muscle aches.
Does Paxlovid make you feel better?
Paxlov has been shown to be 88% successful in reducing severe illness, hospitalizations and deaths from COVID-19 when taken early in the infection.
What are the complications of COVID-19?
Complications can include pneumonia, acute respiratory distress syndrome (ARDS), multiple organ failure, septic shock, and death.
Can infection with COVID-19 cause serious complications? Although most people with COVID-19 have mild to moderate symptoms, the disease can cause serious medical complications and lead to death in some people. Older adults or people with pre-existing chronic medical conditions are at higher risk of getting seriously ill from COVID-19.
How many days can the COVID-19 symptoms last?
How long do the symptoms of COVID last? Those with a mild case of COVID-19 usually recover in one to two weeks. In severe cases, recovery can take six weeks or longer, and some may have persistent symptoms with or without heart, kidney, lung, and brain damage.
How long will I test positive after having COVID-19?
According to the Centers for Disease Control and Prevention, some people infected with COVID-19 may have detectable virus for up to three months, but that does not mean they are contagious. As for testing, PCR tests are more likely to continue to pick up the virus after infection.
