Covid-19 outbreak in California: What is happening in the state?

Over the past few weeks, Google searches for the term FLiRT have increased by 98%. The spike in interest is due to the fact that SARS-CoV-2 — the virus that causes Covid-19 — continues to mutate. In April, a group of new viral strains called FLiRT variants was identified.

The term FLiRT comes from the technical names for their mutations. “This is the term being used to describe a whole family of different variants — including KP.2, JN.1.7, and any other variants starting with KP or JN — that appear to have independently picked up the same set of mutations,” explains the Johns Hopkins University.

According to an article from Yale University, to better understand how the FLiRT strains emerged, it is useful to “see how the SARS-CoV-2 virus has changed over time, with new variants forming as mutations emerged in its genetic code.” The article explains that the Omicron variant of SARS-CoV-2, which took hold in the United States in 2021, gave rise to various subvariants, including JN.1, which was identified in September 2023.

FLiRT variants have become a significant concern in the United States due to their ability to spread rapidly and evade acquired immunity, both from previous infections and vaccines. Indeed, the variants are of such great concern, the Centers for Disease Control and Prevention (CDC) is now closely monitoring them.

What is the KP.3 variant?

The KP.3 variant comes from JN.1.11.1, a direct descendant of JN.1. The main concerns over the KP.3 variant are due to its genetic mutations, especially in the spike protein, which is crucial for the virus’ entry into human cells. These genetic mutations have led to a rapid increase in Covid-19 cases in densely populated regions, with California one of the most affected states in the United States.

Johns Hopkins University reported: “At the end of March, the KP.2 variant was causing about 4% of infections in the U.S., according to the CDC, while its parental strain, JN.1, was causing over 50% of infections at that time. As of early May, KP.2 makes up about 28% of infections, overtaking JN.1 as the dominant variant.” Now KP.3 is gaining ground.

Based on estimates from California Department of Public Health model, KP.3 is expected to be the dominant variant (41.9%).

Who can be affected by the new variants of Covid-19?

People of different ages in the U.S. have been affected by the recorded Covid-19 cases due to the KP.3 variant. Some specialists say that, even if a person has had JN.1, they can become infected with the KP.3 variant, especially if their last infection with Covid-19 occurred several months ago.

What are the symptoms of the new strain?

At this time, common symptoms of the new Covid-19 KP.3 and other variants of the FLiRT strain are:

• Nasal congestion
• Sore throat
• Fatigue
• Headache
• Cough
• Muscle or body pain
• Fever or chills
• Nausea or vomiting
• Diarrhea
• Loss of taste or smell
• Shortness of breath or difficulty breathing

What precautions can be taken to avoid becoming infected?

California’s Department of Public Health continues to recommend vaccination as the primary strategy to reduce the risk of severe illness, hospitalization, and death from Covid-19. But there are other easy measures to follow too:

• Get vaccinated against Covid and stay up to date with vaccines
• Use disposable “surgical” masks, preferably N95 or KN95
• Wash your hands often with soap and water for at least 20 seconds, especially if you have been in a public place
• Use a hand sanitizer with at least 60% alcohol
• Cover your mouth and nose when coughing and sneezing
• Practice social distancing by staying at least two meters away from other people
• Avoid crowded closed places and closed spaces with poor ventilation
• Avoid direct contact with people who have Covid-19
• Regularly clean and disinfect frequently touched surfaces, especially if a family member has had a positive PCR or antigen test result or is sick

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