By Ashe Yee, Parent to Parent Researcher
The Pfizer COVID-19 vaccine was recently given formal approval for use in New Zealand for those aged 16 years and older, and the first shipment has arrived ahead of schedule. Plans are already underway to vaccinate high-priority citizens, which include airline workers, border workers and their family members, and the cleaners, nurses, security staff and hotel workers that work in managed isolation facilities. 70 border workers received the first course of the vaccine on Saturday the 20th of February, and a larger rollout began on Monday the 22nd of February. This initial wave of vaccinations is expected to take approximately one month as there are around 12,000 workers that need immunisation.
The Pfizer vaccine requires two doses given three weeks apart and is approximately 95% effective. Fever, muscle pain, and fatigue are among the common side effects experienced in the days after the vaccination (more likely after the second shot), and there will be a required 30-minute observation period after the vaccine is administered. The vaccine will be completely free for all New Zealand citizens, and vaccination, while recommended, is not mandatory. It has not been approved for people under 16 due to lack of clinical trial data on its effects on younger people. Pregnant women are advised to discuss the risks and benefits with their doctors, and those on certain cancer medications (Keytruda, Opdivo, Yervoy, and Tecentriq) are recommended to not get the vaccine.
The Ministry of Health considers disabled people, people with chronic illness, staff in residential care, and carers of disabled people to be a priority, however details for when people in this priority group can expect to receive the vaccine will not be released until the phased roll-out of the general population gets closer (currently estimated to be mid-year).
Some people are worried about the safety of the Covid-19 vaccine because of the quick development time. Traditionally, vaccines have contained a weakened virus or the signature proteins of the virus they are trying to protect against. This type of vaccine is effective, but very time consuming to develop because it involves identifying a strain, growing the virus to produce a less dangerous hybrid virus, and injecting the new virus into primary cells (e.g. a chicken egg in the case of the flu) to create more copies before then extracting the viral protein to be purified. This method the COVID-19 vaccines use however, eliminate a lot of the manufacturing process that is required for traditional vaccines.
The COVID-19 vaccines are different because rather than containing the viral protein itself, they instead contain genetic instructions called mRNA. The way our immune system works is that our immune cells attack foreign entrants to our body. This includes proteins, viruses, and bacteria. When we are first exposed to a virus, it takes our immune system a while to build up the resources to fight back against the virus during which time the virus will replicate, and we will get sick. Once we have fought it off once however, our immune system will ‘remember’ the virus, and the next time we are exposed our body will use our past experience with it to kill the virus before we get ill.
When it comes to the COVID-19 vaccine, scientists were able to isolate an infectious protein on the outside of the virus. They were able to take the ‘blueprint’ of the protein and make an mRNA version of it. In layman’s terms, they were able to create a set of genetic instructions to teach our body how to make the COVID-19 virus protein. We don’t actually get any of the virus in the vaccine, just these instructions on how to make the protein, so there is no chance we can become infected with COVID-19 FROM the vaccine. Our cells follow these instructions and make the protein, which our immune system then notices and attacks. We can sometimes feel this ‘attack’ in the form of vaccine side effects like fevers, aches etc. This is our body doing what it is supposed to by destroying the foreign protein.
Our cells now ‘remember’ this COVID-19 protein, and how to destroy it. The mRNA instructions we get from the vaccine also get broken down by the body too, so they aren’t hanging around in there forever. The vaccine also doesn’t alter our DNA in any way. So now, if we get exposed to the actual COVID-19 virus (which our body has never seen before), our ‘memory cells’ will recognise the protein on the outside of the virus (the protein from the vaccine) and immediately launch a ramped-up attack which destroys the virus before it has a chance to replicate or make us sick. This is how we become immune to the virus.
If you have any concerns about getting the vaccine when it becomes available, you are advised to discuss this with your doctor.