While Hong Kong is enjoying a relatively peaceful period with no local COVID cases, all of a sudden we were struck by the news that a novel variant of COVID, “Omicron” ( B.1.1.529 variant ) had swept the world with worry and fear, While at the same time we found local infection cases again in Hong Kong. What should we be concerned about this variant? In particular, is a booster dose of vaccine a good way to manage it?
What should we watch out about Omicron?
Omicron carries more than 30 mutations in the gene compared with the original strain, which is significantly more mutations compared to other variants, such as Delta variant. These mutations can potentially change the behavior of the virus over three aspects:
In terms of transmissibility, it is likely Omicron is more infectious. Fortunately, since all countries are now more vigilant with infection control, we hope this risk could be contained but we still need to observe. The mode of transmission of Omicron however, is still the same as the original COVID strain, and there is no evidence that variant has become airborne on a large scale.
As for severity, by far there are no reports that people contracted this variant will develop more severe diseases. This said, even if the probability is as low as one in ten thousand people would develop severe illness after contracting Omicron, it would imply a few hundred people will become critically ill in the context of Hong Kong if there is large scale outbreak. This will for sure seriously impact our health system. This explains why we need to remain cautious not to let the variant spread in the community.
Vaccine can prevent death and severe illness
Regarding vaccine effectiveness, current evidence suggests our vaccines can still offer good protection against severe illness and death for Omicron variant. Vaccine works by inducing the body to produce antibodies, and antibody is our main tool of defense against the virus.
One thing to note however, is that even we get vaccinated, antibody level in our body will drop with the course of time. For the time being though, taking a booster dose is identified as the most effective method to increase our antibody level and maintain protection.
How to choose which vaccine as booster?
At the present moment, immunocompromised individuals, such as cancer patients receiving chemotherapy or transplant recipients on immunosuppressants, are already entitled to receive a booster dose. For people received 2 doses of COVID-19 vaccine for more than 6 months, they are also entitled to receive booster dose.
When it’s come to vaccinate or not, the safest and most official advice, is to tell people to follow their personal preference. This advice is not of much help though, as the public in general do not have much understanding of different vaccines, and it is therefore difficult for them to decide what to prefer.
Based on scientific facts, BioNtech can induce a stronger immunity response than Sinovac. Hence for a person with weaker immunity or previously only received Sinovac, a booster dose of BioNtech can provide more immune protection.
Side effects of booster dose
Many people are worried if side effects of booster dose will be more severe. In fact, for common side effects such as muscle ache or fever, the severity is similar to that of after receiving the first or second dose.
Furthermore, these side effects are in general tolerable and of short duration. If necessary, analgesics that can be bought in local pharmacies over the counter, such as paracetamol, are very effective to reduce discomfort.
As to whether the chance of complications is higher with booster dose, in simple terms, the risk is very low and there is no need to worry.
All in all, the emergence of Omicron is something we should be concerned but not fear about. Mutation in virus is a constant phenomenon, it does not begin with Omicron nor will it end with Omicron. As long as we do well in hand hygiene, universal masking, social distancing and receive vaccination, we will be able to storm through this pandemic.
The above content is reviewed by Dr Alexander Chiu - Chief Medical Officer of AXA Hong Kong and Macau
Information and materials provided is general in nature and does not constitute medical or health advice from AXA Hong Kong and is on an “as is” and “as-available” basis without representation and/or warranty of any kind, either express or implied. While AXA Hong Kong has taken reasonable care in providing such information and materials, they are not specific to your investment objective, financial situation, health or medical conditions or particular needs. No warranty or responsibility is assumed by AXA Hong Kong and our related or holding companies regarding non-infringement, security, accuracy, completeness, adequacy, reasonableness, fitness for a purpose or free from computer viruses in connection with the information and materials provided. AXA Hong Kong and our related companies and holding companies do not accept any liability for any loss, damage, cost or other expense, whether wholly or partially, directly or indirectly, arising from any error, inaccuracy or omission of the information and materials to the extent that such liability is not excluded by law.