Understanding Arcturus
Arcturus, designated as XBB.1.16, is one of the numerous Omicron sub-variants that have been circulating since early 2022. It has become a significant contributor to the recent surge in COVID-19 infections,
notably in India where it is rapidly outcompeting other strains. The World Health Organization has classified XBB.1.16 as a variant of interest, tracking its spread across more than 33 countries, with thousands of reported sequences. In the United States, Arcturus accounts for a notable percentage of current cases, indicating its growing prevalence and the need for continued vigilance.
Symptoms in Children
A particularly concerning aspect of the Arcturus variant is its tendency to manifest distinct symptoms in younger populations. Pediatricians have observed a higher incidence of high fever and conjunctivitis, commonly known as pink eye, in children infected with this strain. This observation, first highlighted by Dr. Vipin M. Vashishtha, noted that conjunctivitis was present in nearly 42.8% of affected infants. The article mentions that the youngest infant diagnosed was merely 13 days old, underscoring the vulnerability of even newborns. Unlike previous waves where respiratory symptoms dominated, Arcturus seems to present with more unusual symptoms in infants, including itchy, non-purulent conjunctivitis. Other symptoms like cough, runny nose, fever, loose stools, and vomiting have also been reported.
Symptoms in Adults
For adults, especially those who have received at least one COVID-19 vaccine dose, the symptoms associated with the Arcturus variant tend to align more closely with those observed in earlier waves of the pandemic. Common presentations include body aches, fever, significant muscle pain, abdominal discomfort, and diarrhea. While these symptoms are familiar, experts suggest that Arcturus might be associated with a higher grade of fever compared to other variants. Dr. Vashishtha also noted that the current outbreak, driven by Arcturus, typically causes a mild febrile illness with a duration of only 1 to 3 days, with young infants appearing to be disproportionately affected compared to older children.
Global and National Prevalence
The Arcturus variant (XBB.1.16) has demonstrated a rapid ascent in its prevalence, particularly in India, where it is driving the current wave of infections. At the time of the report, over 4,000 new cases were recorded in a single day in India, indicating its significant impact. Virologists observe that Arcturus is not only increasing in number but is also outcompeting other circulating variants at an accelerated pace. The concern is amplified by the potential for increased transmissibility and severity, although further genome sequencing and tracking are crucial for a comprehensive understanding. The variant was initially detected in India in January 2023, and its subsequent spread highlights the dynamic nature of viral evolution and the importance of ongoing public health surveillance.
