Rise of Concerning New COVID Variants HV.1 and JN.1

The Rise of New COVID Variants HV.1 and JN.1

As the COVID-19 pandemic continues into its third year, the virus that causes the disease, SARS-CoV-2, has continued to evolve and mutate into new variants. Two variants that have emerged more recently and are under close scrutiny by health authorities are HV.1 and JN.1.

Introduction to the HV.1 Variant

The HV.1 variant, also known as Kraken XBB.1.5, is currently the most dominant COVID variant in circulation in the United States. It is a descendant of the omicron XBB variant first detected in October 2022. HV.1 is extremely transmissible and has mutations that allow it to evade immunity provided by vaccination or previous infection.

According to the U.S. Centers for Disease Control and Prevention (CDC), HV.1 accounted for over 40% of COVID cases in the week leading up to January 7, 2023. Its rapid growth is concerning as it shows the virus' ability to mutate to be more infectious and immune-evasive over time.

Key Mutations and Transmissibility of HV.1

The HV.1 variant contains multiple mutations in the spike protein that SARS-CoV-2 uses to enter and infect cells. These include deletions at spike sites H197 and V234, which help the virus evade antibodies acquired through vaccination or previous infection.

In a recent study that has not yet been peer-reviewed, researchers found that neutralizing antibodies from current COVID vaccines, previous omicron infection, and most monoclonal antibody treatments were substantially less effective against HV.1 compared to earlier variants.

Besides its enhanced immune evasiveness, HV.1 also spreads faster than other currently circulating variants. Researchers estimate that HV.1 has a transmission advantage of around 30% over earlier forms of omicron, though some estimates are even higher.

JN.1 Variant Emerging Outside United States

As HV.1 variant cases surge in the U.S., international health authorities are tracking the spread of another omicron descendant known as JN.1. This variant was first detected in January 2023, with early cases found primarily in Europe.

Like HV.1, the JN.1 variant harbors multiple mutations affecting the spike protein that increase the virus ability to evade immunity from vaccination and prior infection. However, JN.1 does not share the exact spike deletions seen with HV.1 and has a slightly different genetic signature.

JN.1 infections are rising quickly across more than 30 countries, suggesting that it is highly transmissible. In some countries like Austria and Belgium, JN.1 may comprise over 25% of sequenced COVID cases. Its rapid growth and immune evasive properties warrant continued monitoring and assessment going forward.

Impact and Severity of New Variants

A key question surrounding new SARS-CoV-2 variants like HV.1 and JN.1 is whether they cause more severe disease. Unfortunately, definitive conclusions remain limited as larger data sets and more thorough clinical evaluations lag behind the pace of viral evolution.

Currently, there is no clear evidence that HV.1 infections result in higher hospitalization rates or increased disease severity compared to previous omicron variants. Most HV.1 cases thus far have been relatively mild.

However, medical experts caution that its rapid spread could still overwhelm healthcare systems. Its ability to reinfect people within months of previous COVID bouts also heightens concerns about serious illness in high-risk groups if immunity is blunted.

Challenges for Vaccines and Treatments

The continued emergence of new SARS-CoV-2 variants capable of escaping built-up immunity underscores the need for updated vaccines and treatments. All the COVID shots authorized to date were designed around the virus original strain from 2019.

While these vaccines still provide protection against severe disease and death, their effectiveness at preventing infection and transmission diminishes substantially against newer variants like HV.1 and JN.1. Public health experts stress that updated boosters better matched to circulating strains are essential for the best protection.

Similarly, antibody treatments like bebtelovimab are seeing reduced efficacy against these highly mutated omicron offshoots. This threatens doctors ability to provide effective treatments for high-risk patients who become infected.

Recommendations from Health Organizations

Despite the rapid rise of variants like HV.1 and JN.1, public health recommendations regarding COVID have largely remained consistent.

Health organizations universally endorse staying up-to-date with the recommended COVID vaccine doses, including updated bivalent booster shots. They also advise wearing well-fitting masks in public indoor settings or around high-risk groups. Additional protective measures include improving indoor ventilation, testing before gatherings, and staying home when sick.

Outlook Moving Forward

As the COVID-19 pandemic moves into its fourth calendar year, the continued evolution of the SARS-CoV-2 virus remains an obstacle to overcoming the global health crisis. The recent rise of variants like HV.1 and JN.1 demonstrates that the virus still has ample room to mutate in ways that enhance its infectiousness, immune evasion, and reinfection capacity.

Nevertheless, through ongoing surveillance, up-to-date vaccines, improved treatments, and responsible public health measures, experts express measured optimism that the worst consequences of the pandemic can be prevented moving forward. Staying informed about key developments and listening to science-based health guidance remains paramount for all individuals and communities.

Disclaimer: This article is for informational purposes only and does not constitute medical advice. Always consult with a healthcare professional before starting any new treatment regimen.