The UK NHS is now rolling out the Pfizer/BioNTech vaccine (approval documentation). As there is a limited supply of the vaccine, a limited capacity to deliver it and 65 million people to be vaccinated, a priority list has been drawn up by the Joint Committee on Vaccination and Immunisation (JCVI).
People will be offered this vaccine according to their vulnerability to infection by COVID, or the risk that they will transmit the virus to a vulnerable person, so top priority is going to the eldest and those who care for them.
Once all of those over age 75 (approximately 5 million people) have been vaccinated then the extremely highly vulnerable will be vaccinated (i.e. on the grounds of their health condition. These are likely to be those who have had a letter from their doctor or UK.gov this year informing them that they are highly vulnerable, which includes chronic pulmonary aspergillosis, but not all allergic bronchopulmonary aspergillosis).
The UK has ordered enough vaccine for 20 million people so we have enough to vaccinate all of the most highly vulnerable people (defined as all those over age 50, plus all the with high vulnerability), however, the UK government has said that it will take until April 2021 to vaccinate all of these most vulnerable people.
NOTE there have been two cases of people who appear to have had an allergic reaction to the Pfizer/BioNTech vaccine in the first few days of the vaccination program. As planned these episodes have been very quickly reported to the regulatory authorities responsible for closely monitoring all health outcomes (UK Medicines and Healthcare products Regulatory Agency (MHRA)) and precautionary advice has been issued to everyone administering the vaccine.