1. New Covid variants kp.3 and kp.2: what are they?
The new variants KP.3 and KP.2 variants of Covid-19 are recent mutations of the SARS-CoV-2 virus that have drawn the attention of experts due to their increased contagiousness and immune evasion capabilities compared to previous variants.
Characteristics of the Covid kp.3 variant
The KP.3 variant of Covid-19, a sub-variant of the JN.1 mutation, has emerged as a major contributor to the recent surge in cases in Italy and the United States. This variant has shown a higher transmission capability than previous ones, leading to a significant increase in cases during the summer months, a period historically associated with a reduction in SARS-CoV-2 infections.
The symptoms of KP.3 are very similar to those of previous Covid-19 variants. Infected individuals may experience fever, cough, sore throat, headache, red eyes, muscle and joint pain, general malaise, fatigue, and in some cases, gastrointestinal problems such as nausea and diarrhea.
Global spread of the kp.3 variant
The spread of the KP.3 variant of Covid-19 has become significant globally, demonstrating an increased contagion capacity that has surprised many experts. In the United States, this variant quickly became prevalent, accounting for about 25% of Covid-19 cases according to CDC projections between late May and early June 2024. This increase surpassed the prevalence of the KP.2 variant, highlighting the rapid spread of KP.3 among the population.
The emergence of KP.3 has also impacted Europe. In Italy, this variant has been identified as one of the main factors behind the recent rise in Covid-19 cases. Despite the increase in infections, the number of hospitalizations has not shown a corresponding significant rise, thanks to the protection offered by vaccines and previous infections. KP.3’s transmission capacity has not been limited to local infections but has also involved international travelers. Airport screenings in the United States have detected the presence of KP.3 among passengers from various countries, including France, Germany, Italy, Japan, and the United Kingdom. These data suggest that the variant has a strong cross-border transmission capability, facilitated by international air travel. In Spain, sequences of the KP.3.1.1 sub-variant have been detected in several regions, including Madrid, Catalonia, and Andalusia, indicating a wide and varied geographical distribution within the country. The presence of KP.3 has also been documented in other countries such as Canada, highlighting a spread that extends well beyond European and North American borders. This rapid global spread of the KP.3 variant underscores the importance of continuous and accurate monitoring of SARS-CoV-2 variants, as well as the need to adapt vaccination and prevention strategies to address the new challenges posed by highly contagious variants like KP.3.
Impact of the kp.3 variant on infection trends
The KP.3 variant of Covid-19 has had a notable impact on global infection trends, characterized by greater contagiousness compared to previous variants. In Italy, the emergence of KP.3 has been associated with an increase in cases during the summer of 2024, a period traditionally observed to see a reduction in respiratory infections. This increase highlighted how SARS-CoV-2 can still surprise experts, despite predictions of a seasonal decline in infections. The expansion of KP.3 has contributed to a rise in the number of positive tests and the positivity rate, which in Italy increased from 3.2% to 4.7% in a few weeks. Experts have observed that although KP.3 is more contagious, it does not seem to cause more severe illness than previous variants. This observation is supported by data showing a relatively stable number of hospitalizations and deaths despite the increase in cases.
Vaccine efficacy against the kp.3 variant
The efficacy of vaccines against the KP.3 variant of Covid-19 is a topic of great interest and importance, especially in light of the increased infections associated with this variant. Studies and observations conducted so far indicate that despite KP.3’s greater contagiousness, the currently available vaccines continue to provide significant protection against severe forms of the disease and hospitalizations.
In Italy, the increase in cases due to KP.3 has not led to a proportional increase in hospitalizations. This data suggests that vaccines, along with immunity acquired from previous infections, are playing a crucial role in mitigating the disease’s impact. Franco Locatelli, president of the Higher Health Council, emphasized that the protection offered by vaccinations and previous infections has been key in keeping the number of severe cases and hospitalizations low despite the spread of the variant.
In the United States, the Food and Drug Administration (FDA) has determined that new vaccines for the fall should target emerging variants such as KP.2 and KP.3. This adjustment indicates the need to update vaccines to effectively address new variants that present significant mutations compared to previous strains. Experts believe that such updates will help maintain the high efficacy of vaccines in preventing both infection and severe forms of the disease caused by KP.3.
Despite the increased contagiousness of the KP.3 variant, the current protection offered by vaccines appears sufficient to prevent severe outcomes in a large portion of the population. However, the continuous evolution of the virus and the emergence of new variants require constant monitoring and potential adjustments to vaccination strategies to ensure optimal protection. The ability of vaccines to reduce severe symptoms and hospitalizations, even in the presence of more contagious variants, is a key factor in managing the pandemic and reducing the pressure on healthcare systems.
Characteristics of the Covid kp.2 variant
The recently emerged Covid KP.2 variant is rapidly spreading and is becoming dominant in several regions. Belonging to the Omicron family, KP.2 is characterized by specific mutations that allow it to partially evade immunity acquired from previous infections or vaccinations. These mutations are primarily located in the spike protein of the virus, enabling a greater ability to bind to human cells while evading the host’s immune response. Clinically, the KP.2 variant does not seem to introduce significantly new or different symptoms compared to previous variants.
Common symptoms include fever, sore throat, and other typical disturbances of SARS-CoV-2 infections. However, there is not yet enough data to determine with certainty the virulence and aggressiveness of this new variant. Experts are closely monitoring the situation to better understand its impact on public health. Regarding vaccine efficacy against KP.2, early indications suggest that although the variant may evade some of the immunity induced by current vaccines, a certain degree of protection is still maintained, especially against severe forms of the disease. Health agencies are working to update existing vaccines and develop new formulations that can offer more effective protection against this and other emerging variants.
Prevention and control measures to limit the spread of new variants
To limit the spread of new Covid-19 variants, including KP.2 and KP.3, it is essential to implement a series of prevention and control measures involving both the general population and healthcare institutions. An integrated and flexible approach, adapted to the specific characteristics of the variants, is crucial for maintaining control of the pandemic.
First and foremost, vaccination remains one of the most effective weapons in the fight against Covid-19.
In parallel, continuous monitoring through the genetic sequencing of viral samples is crucial for quickly identifying new variants and understanding their spread. This allows health authorities to promptly adapt control measures and inform the public about current risks. For example, the detection of variants in wastewater samples can provide an early signal of rising infections in a community, allowing for targeted preventive interventions.
Individual preventive measures remain essential, especially in high-density or poorly ventilated environments. Wearing masks, maintaining physical distancing, and practicing good hand hygiene are practices that continue to be recommended. Ventilating indoor spaces is particularly important to reduce airborne transmission of the virus, especially in public places and on public transportation.
The importance of regular testing cannot be underestimated. Diagnostic tests, both PCR and antigen, allow for the rapid identification of positive cases and the isolation of infected individuals, reducing the possibility of further contagion. It is crucial that tests are accessible and widely used, especially in the presence of symptoms or after exposure to a confirmed case.
Finally, clear and transparent communication from health authorities is crucial to ensure the public is well-informed about the measures to adopt and the importance of vaccination. Public information campaigns and regular updates on variants and the effectiveness of preventive measures help maintain high awareness and community cooperation.
Future prospects of the pandemic in light of new variants
Regulatory agencies, such as the FDA in the United States, are already working to develop targeted vaccine formulations that can offer optimal protection against variants like KP.2 and KP.3. The implementation of global vaccination will be crucial for controlling the pandemic. Countries with high vaccination rates generally see fewer hospitalizations and deaths, even with the spread of new variants. It is therefore essential to increase vaccine access in low- and middle-income countries to reduce global disparities in protection against the virus.
In the long term, it is possible that Covid-19 will become endemic, with the virus continuing to circulate at manageable levels due to immunity acquired through vaccinations and natural infections. However, vaccination campaigns and booster programs will continue to play a crucial role in keeping severe cases under control and preventing new epidemic waves.
