We’re going to be chasing variants for a while if global immunity levels don’t improve

The past few days have seen global headlines inundated with news about the Omicron variant (B.1.1.529) as the WHO declared it a Variant of Concern so first, I want to remind people to seek information from credible sources and not just read headlines or random social media posts. To not panic but to be alert as scientists globally work out what’s going on; drawing strong conclusions require evaluation of scientific data (the more the better) which is currently limited on Omicron. Scientists in South Africa have made a tremendous effort (and continue to do so) with genomic surveillance (tracking how the virus spreads and evolves by sequencing its genome) to alert the world on the existence of Omicron (so far detected in 23 countries including countries issuing travel bans themselves) and its rapid spread in the southern part of Africa. Genomic surveillance should be implemented in Guyana instead of relying on external sources (see my letter on April 26th).

Yes, as the headlines report, the Omicron variant carries mutations not seen in combination before but whether this confers greater transmissibility (spreads easier/faster) or makes COVID more severe is not clear right now. Data coming out of South Africa shows increasing infection numbers and rates of hospitalization; from the genomic surveillance data, 88% of infections in South Africa, to date, are due to the Omicron variant (source: Our World in Data) while the rest is due to the Delta variant. The increased hospitalization may due to more overall cases but this is being worked out. South Africa, like many countries in the developing world, is experiencing the worse of vaccine inequity with only about 25% of people fully vaccination (Africa – just under 8% fully vaccinated).

One of the biggest questions is will vaccines still work against this variant. Yes, likely so. It’s unlikely that the Omicron variant will escape all the protection we’ve built up with vaccine-induced immunity. Post vaccination we develop antibodies (those defense molecules able of neutralizing the virus) capable of recognizing different parts of the virus so even if it’s changed (via mutations) parts can still be recognizable by our immune system. Our immune system also has ‘memory’ where the cells which make antibodies, over time, can make antibodies which better respond to variants. How antibodies bind to Omicron in order to neutralize it is being studied around the world, so more will be known in a few weeks. Note, that our immune system/response involves more than just antibodies, but antibodies can be measured, so it’s easier for scientists to track immune responses and antibody neutralizing ability in this manner. There is also the question on immunity acquired from getting COVID itself (so-called natural immunity). Preliminary data shows that there may be a higher risk of reinfection, so vaccine induced immunity is still a much safer bet; in fact, quite a robust immune response is obtained if vaccinated after recovering from a COVID infection. Vaccines are also being modified by some manufacturers to specifically target Omicron but they have to go through clinical trials and the whole regulatory approval process again so this may take months.

Given that global vaccination (immunity) levels are far from high enough to fully suppress the virus, yet another SARS-CoV-2 variant of concern isn’t a surprise, but we already know how to deal with it, to protect ourselves and others:

1. Get vaccinated (if you haven’t already). Regardless of any possible reduction in vaccine effectiveness against Omicron, some protection is better than none and more importantly, you will be contributing to improving collective immunity levels (we need high immunity levels to suppress the virus). It has been scientifically shown that the frequency of virus mutation has a strong correlation with low vaccine coverage (more on this in letter on Sept 17). Worse forms of the virus emerge in areas of low vaccine coverage and in vulnerable people/populations. Remember, the Delta variant (still dominant in most places, for now), emerged in India when less than 4% of their population had received a first vaccine dose. It’s hypothesized by some scientists that Omicron emerged in a person infected with HIV who was also infected with SARS-CoV-2 for 6 months. There are many reports of immunocompromised/vulnerable people having prolonged SARS-CoV-2 infections.

2. Get a booster shot (if available and you are eligible). We know booster shots significantly increase protective antibody levels. Preliminary reports from Israel’s Health Ministry indicate the vaccinated or the vaccinated plus boosted have

protection against Omicron but they still need to do more detailed analyses in the coming weeks as more data becomes available.

3. Keep being cautious - wear masks, wash hands, keep your environment hygienic and keep your distance (as much as possible although it may be difficult when in public transport or at work so masks in these instances are important), cooperate with public health measures. The virus is airborne so keeping your surroundings well ventilated will help and easily achievable in Guyana with no winter season where people are mostly confined indoors.

The pandemic is not an easy fix with global immunity levels still low, a consequence of low global vaccine coverage majorly enabled by vaccine inequity and to a lesser extent people just not taking the vaccine (they must). We’re going to be chasing variants for a while if global immunity levels don’t improve significantly soon and we have large areas in the world with very low vaccine coverage from which variants of concern can emerge. Therefore, we must do our part locally in contributing to this collective immunity level by getting vaccinated, which at the same time offers us individual protection. SARS-CoV-2 is going to be around for a while (more on this in my letter on April 26th), likely to become endemic (if not already) but we don’t have a mild form of the virus (like the flu or current endemic coronaviruses which cause mainly mild respiratory infections in most) that will allow us to just throw caution to the wind by relaxing control measures. Every control measure is an added layer of protection, still very much necessary, with vaccination at the top of the list as it remains the safest way to prevent the severe form of COVID.

Sincerely,

Jacquelyn Jhingree, PhD (Scientist in Vaccine/Drug R&D)