Covid-19: Experts urge caution as Kraken rises

Kraken or XBB.1.5, the latest descendant of the XBB variant of Omicron, is said to be the most infectious and dominant of all COVID-19 variants to date and has sent health experts into a tizzy.

The variant has been detected in twenty-eight countries, of which the US, Japan and Singapore are the worst affected.

Experts have now called for Indian public health authorities to expand screenings at international airports and borders for XBB.1.5, which has been named after the legendary sea monster due to its rapid transmissibility.

The spread of Kraken in a populous country like India can create new challenges for the already burdened healthcare system and timely screening, detection and isolation will play a paramount role in preventing a new surge, caution health experts.

New variant spread rapidly

Dr Wiqar Shaikh, professor of medicine, Grant Medical College and Sir JJ Group of Hospitals, expressed concern about the arrival of the variant as XBB has already been detected in India. "The WHO has termed Kraken the most transmissible and most dominant COVID-19 variant to date," he said.

Dr Shaikh quoted an article published in the journal Cell on December 13, 2022, which concluded that Kraken has the ability to evade both natural immunity as well as the protection provided by vaccines. It also has the ability to reinfect people who have earlier suffered from COVID-19. The article by researchers from Columbia University, New York, said that Kraken is a recombinant sub-variant, which means it is the result of fragments from two variants merging together.

Also read: Covid-19 in China: It is business as usual albeit with adherence to protocol, say Indian students

Spike in hospitalisations

Dr Shaikh said that Kraken has spiked US hospitalisations by 16.1 per cent in the past week and accounts for 41 per cent of all COVID-19 cases there. According to the US Centre for Disease Control (CDC), Kraken comprised 75 per cent of all COVID-19 cases in the Eastern US. In fact, it has spread to 29 countries, including European ones.

Dr Shaikh added that the symptoms of Kraken are similar to those displayed by people infected by previous COVID-19 variants - fever, chills, cold, sore throat, difficulty in breathing, fatigue, body ache, headache, loss of taste and smell, nausea and diarrhoea.

Dr Shaikh also quoted from an article from the journal bioRxiv, published on January 3, by researchers from Beijing University, China, which concluded that the "enhanced transmissibility of XBB.1.5 has the potential to spawn more dangerous variants of COVID-19". Another cause for concern is the fact that Kraken binds itself tightly to the cells it infects, which means that the virus can easily replicate in the host.

Numbers speak

Dr Subhash Hira, an infectious disease specialist and professor of global health at the University of Washington, Seattle, and member of several WHO pandemic panels, said, "By the end of December 2022, XBB.1.5 accounted for 40 per cent of cases in the US. It is a recombinant form of sub-variant BA.2. In the northeast region of the US (New York, New Jersey, Maine, etc), about three out of four cases now are caused by XBB.1.5 and it is spreading rapidly to South and North Carolina. Hong Kong, Singapore, Japan, South Korea, India and 24 other countries have reported few cases among international visitors. Deaths attributed to COVID-19 increased by 15 per cent in the US in December. However, China continues to ignore global requests to report new sub-variants beyond BF.7. As in the US, there has been a steady rise in hospitalisations in Hong Kong and Singapore. So far, the clinical illnesses are similar to those caused by the earlier sub-variants, and XBB.1.5 is susceptible to vaccine-induced immunity."

Dr Hira added, "All travellers coming to India from affected countries should be strictly tested and genome sequencing should be made mandatory for early detection of the new variant."

Spread ten times faster

Dr Hira added, "XBB.1.5 is reported to be spreading almost ten times faster than the earlier BA.2 and BQ.1 sub-variants in the US. National governments across the globe are showing fatigue in keeping up with new mutants emerging almost every month. Only time will tell what special mutations of XBB.1.5 will do. Meanwhile, we should continue with masks, sanitisation and physical distancing."

Poor data on vax protection

Dr Ketan Vagholkar, professor of surgery at DY Patil Medical College, said, "XBB.1.5 is being predominantly seen in the US and is spreading fast to other countries. The data is insufficient to prove it is more lethal than previous variants. Whether existing vaccines can render protection against this strain is debatable. It is exhibiting the phenomenon of immune escape. As a result, neither previous infections nor vaccines will render any protection."

Don't panic

Dr Vagholkar added that a runny nose, cough and feeling of congestion are the main symptoms. "These symptoms are seen in people who have either suffered from COVID or have been vaccinated. The symptoms are not severe as seen in typical flu-like illnesses with high-grade fevers. As yet, data is inadequate to study the disease pattern exhibited by this new variant. There is no need for panic. Meticulous use of a mask is the best method of prevention. If cold-like symptoms persist, it is advisable to consult the family physician for guidance and treatment."

Variant of concern

Dr Santosh Bansode, consultant emergency medicine specialist, said, "Since Omicron was labelled a variant of concern, XBB.1.5 is also a variant of concern. As it is the most transmissible variant, we might see an increase in the number of COVID patients in various countries where it is detected."

Be alert and mask up

"Omicron was not a deadly variant so we are not expecting serious patients because of XBB.1.5. But we have to be careful about COVID-positive patients who have travelled from affected countries. If we see any such patient, we must send their samples for genome sequencing. The new variant can infect people who are fully vaccinated but symptoms will be mostly mild. In India, almost all are either vaccinated or have been infected so we already have some immunity and this will help us. We will see mostly mild symptoms. New variants will keep on emerging and we should never panic because of this. We have to be alert and observe what is happening in other countries," Dr Bansode concluded.

Dr Shaikh and other experts urged citizens to wear masks outdoors as well as maintain social distancing.

29
No of nations where XBB.1.5 has been detected