What is COVID-19?
COVID-19, caused by the SARS-CoV-2 virus, emerged at the end of 2019. Variants of SARS-CoV-2 are formed through genetic mutations. During replication, the RNA polymerase copies the virus’s RNA genome. This process is not perfect, and errors, or mutations, may occur. While most mutations do not significantly affect the virus's function or are detrimental, some may give the virus new traits, such as increased transmissibility or the ability to evade the immune system.
Known COVID-19 Variants:
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Alpha (B.1.1.7): First identified in the UK, known for enhanced transmissibility.
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Beta (B.1.351): Discovered in South Africa, shows resistance to some vaccines.
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Gamma (P.1): Originated in Brazil, with mutations in its spike protein.
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Delta (B.1.617.2): Initially found in India, highly infectious and led to severe outbreaks.
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Omicron (B.1.1.529): Noted for numerous mutations, detected in multiple countries.
As of July 15, 2024, the SARS-CoV-2 Omicron variants JN.1, KP.2, KP.3, and LB.1 are prevalent in the US.
Different Types of New Strains:
JN.1:
The JN.1 variant is a descendant of BA.2.86, having acquired the ability for effective transmission through an additional one or two mutations. (BA.2.86 is a variant of SARS-CoV-2 that contains significantly more immune escape mutations—around 30—than any other variant prevalent at that time.) This variant has become the dominant strain, accounting for over 60% of COVID-19 cases in the United States, because JN.1 retains the immune escape capabilities of its parent and has now mutated to be even more transmissible. The newly emerging variants KP.2, KP.3, and LB.1 all originate from JN.1.
KP.2:
The KP.2 variant (also known as JN.1.11.1.2) is a descendant of the JN.1 variant and contains several mutations associated with evading vaccine-mediated immune protection. Preliminary studies (not yet peer-reviewed) suggest that the estimated relative effective reproduction number (Re) of KP.2 could be 1.22 times higher than that of JN.1.
KP.3:
Another rapidly emerging variant, KP.3, is believed to have virological and epidemiological characteristics similar to those of KP.2. However, KP.3 is expected to account for a significant portion of new COVID-19 cases.
LB.1:
LB.1, another recently emerged descendant of JN.1, is also a "FLiRT" variant. It is characterized by additional mutations that may increase its transmissibility and immune escape capabilities. Since early June 2024, preliminary studies suggest that it might potentially replace KP.3 as the dominant variant in the future.
For specifics on the immunity and infectivity of these strains, refer toCOVID-19 Variant Update
Symptoms After Infection with New Strains:
Currently, it is unclear if JN.1 or other variants cause symptoms different from other Omicron subtypes or COVID-19 variants. Generally, symptoms are similar, including:
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Cough
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Sore throat
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Nasal congestion
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Runny nose
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Sneezing
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Fatigue
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Headache
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Muscle aches
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Altered sense of smell
Ultimately, the symptoms and their severity will depend on individual immunity from vaccination and prior infections.
Vaccination and Self-Testing:
Compared to previous strains, the transmissibility of SARS-CoV-2 Omicron variants has increased, though disease severity may differ. Initial data suggest that while transmission might be easier, symptom severity may not necessarily be higher than earlier variants.
Vaccine Efficacy Against New Variants:
Updated COVID-19 vaccines are expected to enhance protection against JN.1 and BA.2.86. Old vaccines, based on previous variants, may not offer as much protection against current strains. This is similar to the annual updates of influenza vaccines to match circulating strains. However, current vaccination rates for COVID-19, flu, and RSV are lagging. Health officials continue to urge vaccination to prevent severe respiratory virus seasons. If you haven’t received the 2023-2024 COVID-19 vaccine and are at high risk for severe illness, it’s not too late to get vaccinated.
Types of Vaccines:
The CDC recommends receiving the updated 2023-2024 COVID-19 vaccines (Pfizer-BioNTech, Moderna, or Novavax) to prevent severe disease.
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Everyone aged 5 and older should get 1 dose of the updated COVID-19 vaccine.
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Children aged 6 months to 4 years may need multiple doses to stay updated, including at least 1 dose of the updated vaccine.
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Moderately or severely immunocompromised individuals may receive additional doses of the updated vaccine.
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Individuals aged 65 and older should receive 1 additional dose of the updated vaccine at least 4 months after their last dose of the 2023-2024 vaccine.
Those who receive timely vaccinations have a lower risk of severe illness, hospitalization, and death from COVID-19 compared to those who are unvaccinated or not fully vaccinated. For more detailed vaccine information, visit Staying Up to Date with COVID-19 Vaccines
Self-Testing:
Do I still need to test for COVID-19?
With the spread of flu and some cold viruses alongside COVID-19, it is important to identify which virus you are infected with, especially if you are at higher risk of severe illness. "It’s important to know if you have COVID-19, the flu, or a non-viral illness (such as strep throat), as they have different treatments," says Dr. Abraar Karan from Stanford Medicine. Early treatment can improve outcomes.
Do new variants affect testing?
Experts see no evidence that new variants affect home rapid tests. “I haven’t seen any indication that new variants are evading detection,” says Karan. While other diagnostic methods have changed early in the pandemic, current tests should still detect these variants. Susan Butler-Wu from USC Keck School of Medicine notes that while data on this specific variant is lacking, if it resembles other variants, testing should not be an issue.
When is the best time to test?
Earlier in the pandemic, people often had the highest viral load when symptoms first appeared, as immunity from infection or vaccination was still developing. Recent research suggests that viral levels might peak a few days after symptom onset. In those with immunity, viral levels peak around the fourth day of symptoms.
(The above information comes from www.nbcnews.com)
Testing Types:
With the high transmissibility of new COVID-19 variants, the US offers tests for detecting current infections through nasal or oral samples.
Nucleic Acid Amplification Tests (NAAT):
Performed by healthcare professionals, NAAT (including PCR) are more likely to detect the virus than antigen tests. NAAT is considered the “gold standard” for COVID-19 testing. Samples are typically sent to a lab and results may take up to 3 days.
Antigen Tests:
Rapid tests that usually provide results within 15-30 minutes. A positive result indicates infection, but antigen tests are less sensitive than NAAT, particularly without symptoms. For accurate results, the FDA recommends two negative antigen tests for symptomatic individuals or three for asymptomatic individuals, spaced 48 hours apart. A single NAAT can confirm antigen results.
How to Get Tested:
Purchase Home Test Kits:
Available online or at pharmacies. Insurance may cover the cost. Visit the FDA website At-Home OTC COVID-19 Diagnostic Tests for authorized tests.
Visit Testing Locations:
Community testing sites, such as local pharmacies or health centers, may offer NAAT or antigen tests at low cost or free. Local health departments may also provide free tests. Discuss other testing options with healthcare providers.
After Testing:
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Positive Result: Follow CDC isolation guidelines undefined | CDC Archive to prevent further spread.
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Medical Care: Seek medical advice and treatment if symptoms worsen.
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Negative Result: Precautions: Follow public health guidelines and CDC self-testing recommendations Search Results | CDC Archive.
Prevention Measures:
Current COVID-19 vaccines are expected to enhance protection against JN.1, similar to other variants. To protect yourself and others:
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Get the latest COVID-19 vaccine.
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Test if you have respiratory symptoms or exposure to COVID-19 cases.
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Improve indoor air quality with portable air purifiers or by opening windows. Use fan options on home thermostats to keep air circulating when hosting visitors.
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Other measures: Wear masks, wash hands frequently, and maintain space and distance. High-quality masks can be lifesaving, especially when interacting with older adults or those with weakened immune systems.
Staying informed and following public health guidelines is crucial as new COVID-19 variants spread. Vaccination, testing, and preventive measures can help mitigate the impact of this evolving virus. Understanding risks and taking appropriate actions can make us strive for a healthier, safer future.
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