Is There A Covid-19 Wave This Winter and Autumn?

A collaborative effort, the COVID-19 Scenario Modeling Hub presented several scenarios for the United States during mid-August. After the spikes caused by the BA.5 Omicron variant, the models showed that the United States could have a relatively calm COVID-19 Season. This was prove vaccine booster campaigns were started quickly and new variants were not developed. Even with the new variant, a significant increase in cases was unlikely.

Justin Lessler from UNC Chapel Hill is the lead of the modeling effort. He said that hospitalizations have fallen in line with projections for more than a month. Other factors could also be a problem. Lessler states that boosters have been slow to roll out, which are designed to target Omicron as well as the original SARS virus CoV-2 strain. There are subtle signs Omicron could be evolving and creating new immunity-dodging variants. Lessler states, “It could cause some increases in the fall or winter months.” Jennifer Nuzzo, an epidemiologist from Brown University in Providence (Rhode Island), says that some states are already experiencing an increase in cases.

Research suggests that there are a number of immune-dodging options being developed worldwide. These options will drive an autumn-winter surge.

New Variants are Behind the Increasing Number of Cases

It is highly unlikely, according to Tom Wenseleers, an evolutionary biologist at the Catholic University of Leuven in Belgium. SARS/CoV-2 is increasing due to a decrease in immunity from previous infections and vaccines. This pandemic is also affecting more people than ever before. According to health officials, social dynamics in many countries have nearly returned to pre-pandemic levels. This includes the United Kingdom. Others respiratory viruses can flourish in cooler months. This could be due to more indoor time.

Is there a new Omicron strain in the pipeline for this fall?

These mutations may include three or more. It is possible to see at least three of these Omicron sub-variants driving past waves — BA.2, Ba.4, or Ba.5 — but their descendants are acquiring mutations that could help them spread.

According to Tom Peacock, a virologist at Imperial College London, SARS-CoV-2-watchers monitor an unprecedented number of variants from many branches within the Omicron family. Although these variants are from different ancestries, they share many of the same mutations within the SARS-CoV-2 spike protein (the part of the virus that the immune system targets). Peacock states, “Clearly, there is an optimal way to have a variant look going into the season.”

Wenseleers stated that “at least one variant or a combination thereof will cause an epidemic.” They all act in the same way so it doesn’t really matter which one is the next big thing.

Why is this Variant on the Rise?

Two words: immune escape. Multiple changes are being track by researchers to the receptor binding domain for spike proteins. Potent antibodies can block infection by targeting the spike protein. Yunlong Richard Cao is an immunologist at Beijing’s Peking University. He believes multiple viruses may be developing the same spike mutations. This is a significant advantage in spreading the virus.

Cao and his colleagues evaluated the potential of the new crop varieties to evade neutralizing antibodies from vaccinations and previous infections with different variants. BQ.1.1, which is a member of the BQ.1 familia, had an additional spike change and was find to be the most immune-evasive. 

What Size Are The Autumn-Winter Waves

Wenseleers estimates that autumn-winter waves will be similar in size to the ones seen in BA.5 surges based on preliminary estimates. This includes the impact on infection rates. It is hard to predict how hospitalizations will change. Researchers believe that admissions will be lower due to the increase in immunity from vaccinations and previous infections than they were during past COVID-19 waves. It is unknown how low this effect might be. Lessler states that although it’s a different game in 2020 and 2021, a surge would still be associated with an increase in deaths and hospitalizations.

Even a mild COVID-19 epidemic could pose problems for hospitals. Already, they are facing backlogs and other conditions which place a substantial burden on the winter health system. Influenza, which hasn’t been detected in the Northern Hemisphere over the past two winters, is expected to return this season. This could lead to fears of a “twindemic” of influenza and COVID-19. Lessler states that hospitals can be quite stressed during flu season.

What do you think about the new vaccines?

Boosters such as bivalent vaccines can provide some protection against infection by new variants. Scientists warn this protection might not last long. Scientists believe one component of bivalent vaccines is built upon an Omicron subvariant — BA.1 in the UK and BA.5 in the United States. There are indications that vaccines encourage the production of neutralizing antibodies, which best recognize Omicron. These antibodies help identify the original virus from which the vaccines were developed. Cao suggests boosters might be necessary to produce high levels of Omicron-specific neutralizing antibodies.