Thailand has recently reported 27 cases of the Omicron sub-variant XBB.1.16, leading authorities to closely monitor its transmission speed and potential for evading the immunity people have developed over months of vaccines and herd immunity. The Ministry of Public Health is urging people, particularly seniors and those with underlying conditions, to receive booster shots in light of the concerns about new outbreaks. Let’s discuss the details of the XBB.1.16 sub-variant.
The World Health Organization (WHO) classified XBB.1.16 as a Variant Under Monitoring (VUM) on March 30 after it was initially detected in January in India. It originates from a combination of Omicron’s BA.2.10.1 and BA.2.75 sub-variants, and its mutation has been found within the spike proteins E180V, F486P, and K478R. This particular mutation on the 478 spots of the spike protein has led to increased transmission speed.
Lab tests reveal XBB.1.16 can be transmitted more efficiently than XBB.1 and XBB.1.5, indicating that it could spread globally at a faster pace. However, no scientific evidence suggests that it will cause more severe symptoms than previous versions of the virus.
Similar symptoms to other sub-variants, such as fever, cough, sore throat, and runny nose, have been reported with XBB.1.16. Unique symptoms include itchy eyes, pink eye, or even “sticky eyes,” although these symptoms have mostly appeared in children from India. Dr. Supakit Sirilak, chief of the Department of Medical Sciences, states that eye irritation has not been officially confirmed as an XBB.1.16-related symptom.
In Thailand, the Department of Medical Sciences has confirmed 27 cases and one death involving this new sub-variant. The deceased patient was a senior citizen. The department expects to see a surge in the caseload following Songkran celebrations and plans to collect 700 samples per week for monitoring purposes.
XBB.1.16 could now account for about 10% of all new COVID infections in Thailand, compared to 30% for XBB. The department believes that by the middle of next month, XBB.1.16 will become the dominant strain. Thailand is following the WHO’s recommendation to diligently monitor the situation, as XBB.1.16 has grown from comprising 0.21% of all new global COVID-19 infections in late February to an estimated 3.96% a month later. In the United States, it represented 7.2% of all COVID-19 samples from April 9 to 15.
According to the Department of Disease Control (DDC), a small wave of COVID-19 outbreaks is expected to start in May, with the numbers peaking in June, then declining in line with the usual progress of influenza outbreaks. The DDC anticipates that schools will experience a small surge when students return to classes in May.
The Ministry of Public Health reiterates the importance of caution to prevent infections, urging people to follow self-preventive measures such as wearing masks in public, frequent hand washing, social distancing, and getting vaccinated. It emphasizes that seniors and those with chronic diseases should get a booster shot as soon as possible, particularly if their last dose was administered more than three months ago.
As the Thai ministry continues to provide vaccines free of charge, it now has over 10 million doses of multi-based vaccine platforms. It has also issued guidelines for receiving vaccines, recommending that individuals receive one dose annually, similar to regular flu shots. The dual administration of both vaccines will begin next month.