Debunking the latest fake Covid-19 news and updates on XBB.1.5 and bivalent vaccines
CLINICAL MATTERS
DR. EDSEL SALVANA
It’s a new year and so far, so good! The first week of 2023 showed less than 500 Covid-19 cases per day and only one severe case a day for the entire week. Healthcare utilization remains low and new deaths are less than one a day (17 deaths between Dec. 26. 2022 and Jan. 8, 2023). Vaccines and continued masking are holding the fort, and our current protocols are keeping the virus at bay without sacrificing our economic recovery.
Unfortunately, lots of fake Covid-19 news is circulating again. By now, the script is all too familiar: “The next big variant! The most immune evasion yet! With the potential to kill more people than ever is emerging!” If it was just random people making these statements, it would probably not be of too much import. There are, however, doctors and scientists (typically without the correct expertise) who keep parroting these claims. Worse, traditional media sometimes amplifies this misinformation by quoting these pseudo-authorities, leading to confusion and anxiety. With the number of times these people have cried wolf, you would think they would have already learned their lesson. Sensationalism continues to sell stories and drives traffic to social media accounts regardless of how many times they have been wrong.
During the last couple of weeks of December 2022, a Viber message purported to be from a pulmonary and critical care doctor of a big private hospital flagging that their Covid-19 ICU was full started making the rounds. I was sent the message by multiple contacts, including doctors and academics, asking whether it was true. I was incredulous. How could smart people fall for something like this? It was easy enough for me to check my sources from the hospital itself and from the Department of Health (DOH) that no such thing was occurring. This was not the first time these kinds of messages circulated and we quickly debunked those throughout the pandemic. I cannot believe that educated people would just wantonly share these dubious messages without even doing their homework. Such is the ease with which people can just share messages with the click of a button. Ironically, it would have been just as easy to fact check these claims with a quick Google search and break the chain of disinformation but for whatever reason this rarely happens.
Another fake message circulating at about the same time centered on the Omicron sublineage XBB and how it purportedly had no cough or fever but caused other kinds of symptoms that were different from other variants. It also falsely claimed that XBB was more toxic and deadlier than Delta, that it was usually missed by nasopharyngeal swabs and it “directly infect lungs (sic), leading to viral pneumonia.” Most tellingly, it exhorted people to “don’t keep this information to yourself, share as much as possible with other relatives and friends, especially yours.”
That last sentence at the very end should have been a red flag that this piece of news is trying too hard to be viral. XBB caused a surge in cases in Singapore in October 2022 but did not cause an unusual increase in mortality. It also did not have distinct symptoms, nor was it missed by testing. No new variant has even approached Delta in terms of severity, especially with the high levels of vaccination we currently have. And yet this message was so widely shared that the DOH had to come out and debunk it specifically despite the obvious problems with the original message. I personally saw the message shared in multiple Viber groups and many of us infectious diseases doctors had to jump in to stop the spread.
There is one variant that is being closely monitored by the World Health Organization (WHO) since it is becoming the dominant variant in the US. Known as XBB.1.5, this variant is a descendant lineage of the infamous XBB. The X in XBB denotes that it is a recombinant virus. That means that two viruses infected someone at the same time and the viral genetic material from the two lineages mixed together in an infected cell. This hybrid virus was then transmitted to other people, establishing a new lineage. The recombinant virus can be produced by any of the different lineages and variants and the amount of genetic material from each parent lineage is variable. For instance, XBC is a combination of Delta and Omicron sublineages. XBB is a combination of two Omicron sublineages and so it is classified as an Omicron variant of concern sublineage. The original XBB did cause a spike in cases in Singapore in October 2022. It was detected in the Philippines in the same month but did not trigger any unusual spike in cases.
XBB.1.5 seems to have a modest growth advantage over other circulating variants in the US. This might be from better immune-evasion properties, which can also be affected by other external factors, such as vaccination/boosting and competing subvariants in the community. It also has mutations that may make it more efficient in binding to the ACE-2 receptor, which SARS-CoV-2 uses to enter human cells.
There is no evidence that it can cause more severe disease. It also isn’t a given that it will take over as the predominant variant in other countries. For instance, while XBB did supplant other lineages in Singapore, the same did not happen in the Philippines. BA.5 and BA.2 (and subvariants) remain dominant while XBB continues to circulate according to the sequencing results from Jan. 3 to 9, 2023 (see table below from https://doh.gov.ph/covid19-variants). No XBB.1.5 has been detected based on this sequencing run. Even when XBB.1.5 eventually reaches our shores, it is not expected to drive a large increase in severe cases since the current high vaccination rate and health protocols remain effective.
Our current Covid-19 vaccines continue to protect against severe disease, regardless of variant. The incoming bivalent vaccines for boosting have already received approval for the EUA amendment from the DOH. These bivalent vaccines, which have shown additional protection against both infection and disease severity, will be deployed initially among the highest risk populations. High levels of voluntary masking, especially in Metro Manila, provide an additional layer of security not just against Covid-19 but against other respiratory diseases. Overall, the Covid-19 news for the first days of 2023 is pretty good. Nothing fake about that at all.