Covid 19 Vaccination - children

AuthorityManx Care
Date received2022-05-03
OutcomeSome information sent but not all held
Outcome date2022-05-30
Case ID2424273

Summary

The requester asked for specific vaccination uptake numbers for children on the Isle of Man up to April 6, 2022, but the authority provided a general medical chapter on SARS-CoV-2 instead of the requested statistics.

Key Facts

  • The request was made to Manx Care regarding COVID-19 vaccination data for children.
  • The outcome was classified as 'Some information sent but not all held'.
  • The response document provided is a medical chapter dated February 28, 2022, describing the virus and its variants.
  • The response does not contain the specific vaccination numbers or percentages requested for the 5-11 age group.
  • The document mentions the Alpha, Delta, and Omicron variants of SARS-CoV-2.

Data Disclosed

  • 2022-05-03
  • 2022-05-30
  • 06/04/22
  • 28 February 2022
  • 5-11 year olds
  • 2019
  • 2020
  • 2021
  • 5-6 days
  • 20%
  • 17 days
  • 2 and 3
  • 5.7
  • 50-70%

Original Request

On the 06/04/22 the Manx Care Vaccination team sent a letter to parents of 5-11 year olds which stated "we have already seen a good uptake in the vaccinations offered to children, but we would like to increase this further" I would like to know what age range Manx Care classifies as children regarding vaccination? I am trying to find out what the "good uptake" numbers were before 06/04/22 Please supply, (if possible in individual yearly age groups) the numbers of vaccinated children (and as a percentage of total children if possible) that there were, on the Isle of Man up to 06/04/22.

Data Tables (8)

Category Population Size SARS-CoV-2 antibody prevalence% (95% CI)1 Confirmed COVID-19 deaths2 Infection fatality ratio % (95% CI)2 Estimated number of infections (95% CI)
Total 56,286,961 6.0 (5.7, 6.8) 30180 0.9 (0.9, 0.9) 3,362,037 (3,216,816; 3,507,258)
Sex
- 2-voC-SRAS 91-DIVOC
Male 27,827,831 6.5 (5.8, 6.6) 18575 1.1 (1.0, 1.2) 1,729,675 (1,614,585; 1,844,766)
Female 28,459,130 5.8 (5.4, 6.1) 11600 0.7 (0.7, 0.8) 1,633,785 1,539,821; 1,727,749)
Age (years)
15-44 21,335,397 7.2 (6.7,7.7) 524 0.0 (0.0, 0.0) 1,535,884 (1,436,941; (1,634,826)
45-64 14,405,759 6.2 (5.8, 6.6) 4657 0.5 (0.5, 0.5) 895,238 (837,231; 953,244)
65-74 5,576,066 3.2 (2.7, 3.7) 5663 3.1 (2.6, 3.6) 181,044 (153,426; 208,661)
75+ 4,777,650 3.3 (2.5, 4.1) 19330 11.6 (9.2, 14.1) 166,077 (131,059; 200,646)
Priority group Risk group
1 Residents in a care home for older adults Staff working in care homes for older adults
2 All those 80 years of age and over Frontline health and social care workers
3 All those 75 years of age and over
4 All those 70 years of age and over Individuals aged 16 to 69 in a high risk group1
5 All those 65 years of age and over
6 Adults aged 16 to 65 years in an at-risk group (Table 3)
7 All those 60 years of age and over
8 All those 55 years of age and over
9 All those 50 years of age and over
Clinical risk groups
Chronic respiratory disease Individuals with a severe lung condition, including those with poorly controlled asthma1 and chronic obstructive pulmonary disease (COPD) including chronic bronchitis and emphysema; bronchiectasis, cystic fibrosis, interstitial lung fibrosis, pneumoconiosis and bronchopulmonary dysplasia (BPD).
Chronic heart disease and vascular disease Congenital heart disease, hypertension with cardiac complications, chronic heart failure, individuals requiring regular medication and/or follow-up for ischaemic heart disease. This includes individuals with atrial fibrillation, peripheral vascular disease or a history of venous thromboembolism.
Chronic kidney disease Chronic kidney disease at stage 3, 4 or 5, chronic kidney failure, nephrotic syndrome, kidney transplantation.
Chronic liver disease Cirrhosis, biliary atresia, chronic hepatitis.
Chronic neurological disease Stroke, transient ischaemic attack (TIA). Conditions in which respiratory function may be compromised due to neurological or neuromuscular disease (e.g. polio syndrome sufferers). This group also includes individuals with cerebral palsy, severe or profound and multiple learning disabilities (PMLD), Down’s syndrome, multiple sclerosis, epilepsy, dementia, Parkinson’s disease, motor neurone disease and related or similar conditions; or hereditary and degenerative disease of the nervous system or muscles; or severe neurological disability.
Diabetes mellitus and other endocrine disorders Any diabetes, including diet-controlled diabetes, current gestational diabetes, and Addison's disease.
Immunosuppression Immunosuppression due to disease or treatment, including patients undergoing chemotherapy leading to immunosuppression, patients undergoing radical radiotherapy, solid organ transplant recipients, bone marrow or stem cell transplant recipients, HIV infection at all stages, multiple myeloma or genetic disorders affecting the immune system (e.g. IRAK-4, NEMO, complement disorder, SCID). Individuals who are receiving immunosuppressive or immunomodulating biological therapy including, but not limited to, anti-TNF, alemtuzumab, ofatumumab, rituximab, patients receiving protein kinase inhibitors or PARP inhibitors, and individuals treated with steroid sparing agents such as cyclophosphamide and mycophenolate mofetil. Individuals treated with or likely to be treated with systemic steroids for more than a month at a dose equivalent to prednisolone at 20mg or more per day for adults. Anyone with a history of haematological malignancy, including leukaemia, lymphoma, and myeloma. Those who require long term immunosuppressive treatment for conditions including, but not limited to, systemic lupus erythematosus, rheumatoid arthritis, inflammatory bowel disease, scleroderma and psoriasis.
Some immunosuppressed patients may have a suboptimal immunological response to the vaccine (see Immunosuppression and HIV).
Asplenia or dysfunction of the spleen This also includes conditions that may lead to splenic dysfunction, such as homozygous sickle cell disease, thalassemia major and coeliac syndrome.
Morbid obesity Adults with a Body Mass Index (BMI) ≥40 kg/m².
Severe mental illness Individuals with schizophrenia or bipolar disorder, or any mental illness that causes severe functional impairment.
Younger adults in long-stay nursing and residential care settings Many younger adults in residential care settings will be eligible for vaccination because they fall into one of the clinical risk groups above (for example learning disabilities). Given the likely high risk of exposure in these settings, where a high proportion of the population would be considered eligible, vaccination of the whole resident population is recommended. Younger residents in care homes for the elderly will be at high risk of exposure, and although they may be at lower risk of mortality than older residents should not be excluded from vaccination programmes (see priority 1 above).
Pregnancy All stages (first, second and third trimesters)
Other risk groups
Household contacts of people with immunosuppression Individuals who expect to share living accommodation on most days (and therefore for whom continuing close contact is unavoidable) with individuals who are immunosuppressed (defined as immunosuppressed in tables 3 or 4).
Carers Those who are eligible for a carer’s allowance, or those who are the sole or primary carer of an elderly or disabled person who is at increased risk of COVID- 19 mortality and therefore clinically vulnerable.1
Chronic respiratory disease Including those with poorly controlled asthma1 that requires continuous or repeated use of systemic steroids or with previous exacerbations requiring hospital admission, cystic fibrosis, ciliary dyskinesias and bronchopulmonary dysplasia
Chronic heart conditions Haemodynamically significant congenital and acquired heart disease, or less severe heart disease with other co-morbidity. This includes: • single ventricle patients or those palliated with a Fontan (Total Cavopulmonary Connection) circulation • those with chronic cyanosis (oxygen saturations <85% persistently) • patients with cardiomyopathy requiring medication • patients with congenital heart disease on medication to improve heart function • patients with pulmonary hypertension (high blood pressure in the lungs) requiring medication
Chronic conditions of the kidney, liver or digestive system Including those associated with congenital malformations of the organs, metabolic disorders and neoplasms, and conditions such as severe gastro- oesophageal reflux that may predispose to respiratory infection
Chronic neurological disease This includes those with • neuro-disability and/or neuromuscular disease that may occur as a result of conditions such as cerebral palsy, autism, epilepsy and muscular dystrophy • hereditary and degenerative disease of the nervous system or muscles, other conditions associated with hypoventilation • severe or profound and multiple learning disabilities (PMLD), Down’s syndrome, those on the learning disability register • neoplasm of the brain
Endocrine disorders Including diabetes mellitus, Addison’s and hypopituitary syndrome
Immunosuppression Immunosuppression due to disease or treatment, including: • those undergoing chemotherapy or radiotherapy, solid organ transplant recipients, bone marrow or stem cell transplant recipients • genetic disorders affecting the immune system (e.g. deficiencies of IRAK-4 or NEMO, complement disorder, SCID) • those with haematological malignancy, including leukaemia and lymphoma • those receiving immunosuppressive or immunomodulating biological therapy • those treated with or likely to be treated with high or moderate dose corticosteroids • those receiving any dose of non-biological oral immune modulating drugs e.g. methotrexate, azathioprine, 6-mercaptopurine or mycophenolate • those with auto-immune diseases who may require long term immunosuppressive treatments Children who are about to receive planned immunosuppressive therapy should be considered for vaccination prior to commencing therapy.
Asplenia or dysfunction of the spleen Including hereditary spherocytosis, homozygous sickle cell disease and thalassemia major
Serious genetic abnormalities that affect a number of systems Including mitochondrial disease and chromosomal abnormalities
Pregnancy All stages (first, second and third trimesters)
Other risk groups
Household contacts of people with immunosuppression Individuals who expect to share living accommodation on most days (and therefore for whom continuing close contact is unavoidable) with individuals who are immunosuppressed (defined as immunosuppressed in tables 3 or 4).
Proceed with vaccination (no special precautions) Special precautions Vaccination contra-indicated
SCITSIRETCARAHC TNEITAP ● previous allergic reaction (including anaphylaxis) to a food, insect sting and most medicines (where trigger has been identified) ● previous non-systemic reaction to a vaccine ● hypersensitivity to non- steroidal anti-inflammatory drugs e.g. aspirin, ibuprofen ● mastocytosis ● prior non-anaphylaxis allergic reaction to COVID-19 vaccine ● history of immediate anaphylaxis to multiple, different drug classes, with the trigger unidentified (this may indicate PEG allergy) ● history of anaphylaxis to a vaccine, injected antibody preparation or a medicine likely to contain PEG (e.g. depot steroid injection, laxative) ● history of idiopathic anaphylaxis ● prior anaphylaxis reaction to COVID-19 vaccine ● prior systemic allergic reaction to a component of the vaccine (for known PEG allergy see text above)
SNOITCA ● proceed with vaccination in any setting ● some individuals may be reassured by being observed for 15 minutes (may not be required if previously tolerated the same vaccine) ● some patients (e.g. those with mastocytosis) may benefit from pretreatment with anti-histamine to reduce allergic symptoms ● consider possibility of PEG allergy and seek allergy advice if needed ● a person has previously tolerated a dose of the same vaccine, it is safe to administer in any setting. Otherwise - consider giving vaccine and observe for 30 minutes ● refer to allergist or other appropriate specialist ● consider administration of the implicated mRNA vaccine under medical supervision in hospital, or, where reaction was to AstraZeneca vaccine give alternative vaccine in any setting ● consider observation for 30 minutes
Age Feb.22 Mar.22 1 - 6 Apr.22
5 - 11 years 56 0 0

Full Response Text

1 Chapter 14a - COVID-19 - SARS-Cov-2 Chapter 14a - COVID-19 - SARS-CoV-2 28 February 2022 14a COVID-19 - SARS-CoV-2
NOTIFIABLE The virus COVID-19 disease first emerged as a presentation of severe respiratory infection in Wuhan, China in late 2019 (WHO, 2020). By January 2020, lower respiratory samples taken from affected patients were sequenced and demonstrated a novel coronavirus (SARS-CoV-2) (Huang et al, 2020). The first two cases in the UK were seen in late January (Lillie et al, 2020). In March 2020, the World Health Organization (WHO) declared a SARS-CoV-2 pandemic (WHO Director- General, 2020). SARS-CoV-2 is a member of the family of Coronaviridae and genus Betacoronavirus (Zhu et al, 2020). Phylogenetic analysis of SARS-CoV-2 has shown that it is genetically distinct from the SARS coronavirus (Dhama, et al, 2020), but appears to share strong sequence similarity to bat coronaviruses in China (Lam et al, 2020). As with other coronaviruses, SARS-CoV-2 is an RNA virus which encodes four major structural proteins, spike (S), membrane (M), envelope (E) and a helical nucleocapsid (N) (Dhama et al, 2020) The S glycoprotein is considered the main antigenic target and consists of an S1 and S2 subunit (Kaur et al, 2020). The S1 subunit has two functional domains: the N terminal domain (NTD) and receptor binding domain (RBD) which contains the receptor binding motif (RBM) (Kaur et al, 2020). The RBM binds to angiotensin converting enzyme 2 (ACE2) on host cells and is endocytosed with subsequent release of the viral genome into the cytoplasm (Amanat et al, 2020). SARS-CoV-2 is primarily transmitted by person to person spread through respiratory aerosols, direct human contact and fomites (Kaur et al, 2020). Estimates of the basic reproduction number [R] were initially between 2 and 3 although a recent estimate was as high as 5.7 (Sanche et al, 2020). This high transmissibility indicates that stringent control measures, such as active surveillance, physical distancing, early quarantine and contact tracing, are needed in order to control viral spread. Perinatal transmission has been reported although the exact transmission route has not been elucidated (ECDCa, 2020). After the initial exposure, patients typically develop symptoms within 5-6 days (incubation period) although about 20% of patients remain asymptomatic throughout infection (Cevik et al, 2020). Polymerase chain reaction (PCR) tests can detect viral SARS- CoV-2 RNA in the upper respiratory tract for a mean of 17 days, although transmission is maximal in the first week of illness. Symptomatic and pre-symptomatic transmission (1-2 days before symptom onset), is thought to play a greater role in the spread of SARS- CoV-2 than asymptomatic transmission. During late 2020 and 2021, a range of SAR-CoV-2 variants have emerged, some of which have been associated with increased transmission. These more transmissible variants have become established globally and replaced the original Wuhan strain, being associated with successive waves of infections in many countries. The first widely 2 Chapter 14a - COVID-19 - SARS-Cov-2 Chapter 14a - COVID-19 - SARS-CoV-2 28 February 2022 distributed variant, designated Alpha, first emerged in Kent in late 2020 and led to a second wave in the UK in early 2021. Emergence of the Delta variant, first seen in India, has now been associated with further waves of infection in many countries. Information on variants under investigation is posted each week at: https://www.gov.uk/government/ publications/investigation-of-sars-cov-2-variants-technical-briefings A recent increased incidence in South Africa, associated with a new variant Omicron, has raised particular concern due to a large number of mutations, including many in the spike protein. These mutations appear to be associated with a higher rate of reinfection, suggesting a degree of immune escape. Many countries, including the UK, are now experiencing increases in the incidence of Omicron. Preliminary UK data confirms observations from other countries that the severity of infection due to Omicron is low, with an estimated reduction in risk of hospitalisation of 50-70% (https://www.gov.uk/government/publications/investigation-of- sars-cov-2-variants-technical-briefings). The disease In adults, the clinical picture varies widely. A significant proportion of individuals are likely to have mild symptoms and may be asymptomatic at the time of diagnosis. Symptoms are commonly reported as a new onset of cough and fever (Grant et al, 2020), but may include headache, loss of smell, nasal obstruction, lethargy, myalgia (aching muscles), rhinorrhea (runny nose), taste dysfunction, sore throat, diarrhoea, vomiting and confusion; fever may not be reported in all symptomatic individuals. Patients may also be asymptomatic (He et al, 2020). Progression of disease, multiple organ failure and death will occur in some individuals (Pachetti et al, 2020). Currently available data suggest that increasing age and male gender are significant risk factors for severe infection. However, there are also groups of patients with underlying comorbidities, where infection may result in increased risk of serious disease (Docherty et al, 2020). In a large review of primary care records pseudonymously linked with SARS- CoV-2 status, comorbidities including diabetes, cancer and poorly controlled asthma were associated with increased risk of death (Williamson et al, 2020). Infection fatality ratios (IFR) for COVID-19 in the UK, derived from combining mortality data with infection rates in seroprevalence studies, show a marked increase in IFR in the oldest age groups (Table 1) (Ward et al, 2020). In Europe and the UK, deaths attributed to SARS-CoV-2 have been reported disproportionately from residential care homes (ECDCb, 2020, Graham et al, 2020). Other notable risk groups include healthcare workers (Nguyen et al, 2020) who may acquire infection both in the hospital or within the community setting (Bielicki et al, 2020). Current evidence suggests that deprivation and being from black and asian minority ethnic groups results in a higher risk for death from SARS-CoV-2 infection (Williamson et al, 2020), although the factors that contribute to this are not yet clear. 3 Chapter 14a - COVID-19 - SARS-Cov-2 Chapter 14a - COVID-19 - SARS-CoV-2 28 February 2022 Table 1: UK Infection fatality ratio and estimated total numbers of deaths (February to July 2020) Category Population Size SARS-CoV-2 antibody prevalence% (95% CI)1 Confirmed COVID-19 deaths2 Infection fatality ratio % (95% CI)2 Estimated number of infections (95% CI) Total 56,286,961 6.0 (5.7, 6.8) 30180 0.9 (0.9, 0.9) 3,362,037 (3,216,816; 3,507,258) Sex Male 27,827,831 6.5 (5.8, 6.6) 18575 1.1 (1.0, 1.2) 1,729,675 (1,614,585; 1,844,766) Female 28,459,130 5.8 (5.4, 6.1) 11600 0.7 (0.7, 0.8) 1,633,785 1,539,821; 1,727,749) Age (years) 15-44 21,335,397 7.2 (6.7,7.7) 524 0.0 (0.0, 0.0) 1,535,884 (1,436,941; (1,634,826) 45-64 14,405,759 6.2 (5.8, 6.6) 4657 0.5 (0.5, 0.5) 895,238 (837,231; 953,244) 65-74 5,576,066 3.2 (2.7, 3.7) 5663 3.1 (2.6, 3.6) 181,044 (153,426; 208,661) 75+ 4,777,650 3.3 (2.5, 4.1) 19330 11.6 (9.2, 14.1) 166,077 (131,059; 200,646) 1 All estimates of prevalence adjusted for imperfect test sensitivity and specificity (see text for details). Responses have been re-weighted to account for differential sampling (geographic) and for variation in response rate (age, gender, ethnicity and deprivation) in final column to be representative of the England population (18+). 2 Infection fatality ratios were calculated excluding care home residents. Confirmed COVID-19 death counts were obtained from https://fingertips.phe.org.uk/static-reports/mortality-surveillance/excess-mortality-in- England-week-ending-17-jul-2020.html. Deaths in care homes by age on 12 June 2020 were obtained from www.ons.gov.uk. Total deaths in care home residents up to 17 July 2020 were obtained from www.ons.gov.uk. The age stratified estimates of COVID-19 deaths were then estimated using the total deaths from 17 July and the age distribution from 12 June. We assumed that age distribution of deaths did not change between 12 June and 17 July 2020. 4 Chapter 14a - COVID-19 - SARS-Cov-2 Chapter 14a - COVID-19 - SARS-CoV-2 28 February 2022 Children In general children appear to exhibit mild disease. Although cough and fever are the main symptoms in children (Ladhani et al, 2020), a UK study tracking children of healthcare workers has shown that of those who were seropositive, gastrointestinal symptoms were also commonplace (Waterfield et al, 2020). Initial evidence suggested that children had a lower susceptibility to SARS-CoV-2 infection, and they were unlikely to be key drivers of transmission at a population level (Viner et al, 2020). However, a prospective study found higher secondary attack rates where the household index case was a child (Lopez Bernal et al, 2020). Following the large scale vaccination of adults in the UK, recent rates of reported cases in children have exceeded those in adults. A spectrum of multi system inflammatory disease similar to Kawasaki disease (KD) was was initially identified in children admitted during the SARS-CoV-2 pandemic, temporally associated with severe acute respiratory syndrome attributed to SARS-CoV-2 (Paediatric multisystem inflammatory syndrome temporally associated with SARS-CoV-2 infection (PIMS-TS)) (Whittaker et al, 2020). This severe presentation in children is extremely rare, but appears to encompass a wide range of features, including fever, gastrointestinal symptoms, rash, myocardial injury and shock (Swann et al, 2020). Pregnant women and neonates The risks to pregnant women and neonates following COVID-19 infection have worsened over the course of the pandemic: the maternal mortality ratio as a result of COVID-19 has significantly increased from 1.4 per 100,000 live births in the Wildtype SARS-CoV-2 dominant period to 5.4 per 100,000 live births in the Delta dominant period. (Knight et al, 2021). During the Delta dominant period, six neonatal deaths were recorded. No neonatal deaths were reported in previous waves. The proportion of pregnant women hospitalised with symptomatic COVID-19 that experienced moderate to severe infection increased from Wildtype to subsequent Alpha and Delta dominant periods, and the proportion admitted to intensive care units also increased (Vousden et al, 2021a, https://www.icnarc.org/Our- Audit/Audits/Cmp/Reports). Pregnant and recently pregnant women with COVID-19 are more likely to be admitted to an intensive care unit, have invasive ventilation or extracorporeal membrane oxygenation in comparison to non-pregnant women of reproductive age (Allotey et al, 2021). UK studies have suggested a high rate of stillbirth in infected women (Allotey et al, 2020, Gurol-Urganci et al, 2021), and this appears to have increased during the Delta period (Vousden et al, 2021a). Vertical transmission appears rare (Gale et al, 2021). However, the risk of preterm birth is increased two to threefold for women with symptomatic COVID-19 (Vousden et al, 2021a,b)), usually as a result of a medical recommendation to deliver early to improve maternal oxygenation.1 Pregnant women are more likely to have severe COVID-19 infection if they are overweight or obese, are of black and asian minority ethnic background, have co-morbidities such as diabetes, hypertension and asthma, or are 35 years old or older (Vousden et al, 2021a, Allotey et al, 2020). 1 NICE Guideline 25, 2019 https://www.nice.org.uk/guidance/ng25 5 Chapter 14a - COVID-19 - SARS-Cov-2 Chapter 14a - COVID-19 - SARS-CoV-2 28 February 2022 COVID-19 vaccines The recognition of the pandemic has accelerated the development and testing of several vaccines using platforms investigated during previous emergencies such as the SARS pandemic (Amanat et al, 2020) and Ebola in West Africa. Candidate vaccines include nucleic acid vaccines, inactivated virus vaccines, live attenuated vaccines, protein or peptide subunit vaccines, and viral-vectored vaccines. Most vaccine candidates focus on immunisation with the spike (S) protein, which is the main target for neutralising antibodies. Neutralising antibodies that block viral entry into host cells through preventing the interaction between the spike protein Receptor Binding Motif (RBM) and the host cell Angiotensin-converting enzyme 2 (ACE2) are expected to be protective (Addetia et al, 2020, Thompson et al, 2020). In the UK four vaccines targeting the S protein have been authorised for supply; two use an mRNA platform (Pfizer BioNTech COVID-19 BNT162b2 vaccine (tozinameran)/Comirnaty® and Moderna mRNA-1273 COVID-19 vaccine/Spikevax®) and two use an adenovirus vector (AstraZeneca COVID-19 ChAdOx1-S vaccine/Vaxzevria® and COVID-19 vaccine Janssen Ad26.COV2-S [recombinant]). One other vaccine is now approved for use in the UK, Nuvaxovid® is the COVID-19 vaccine developed by Novavax. This vaccine uses a recombinant S protein (grown in baculovirus infected insect cells) as an antigen with the Matrix-M adjuvant. The latter adjuvant includes two saponins derived from tree bark. COVID-19 Vaccine Janssen and Nuvaxovid® are currently approved for primary immunisation in those aged 18 and older. As there are relatively limited indications for these vaccines in the current programme, they are not currently being supplied routinely in the UK.
The Pfizer BioNTech and Moderna COVID-19 vaccines are nucleoside-modified messenger RNA (mRNA) vaccines. mRNA vaccines use the pathogen’s genetic code as the vaccine; this then exploits the host cells to translate the code and then make the target spike protein. The protein then acts as an intracellular antigen to stimulate the immune response (Amanat et al, 2020). mRNA is then normally degraded within a few days. Both the Moderna mRNA-1273 and the Pfizer BioNTech COVID-19 BNT162b2 vaccines have been generated entirely in vitro and are formulated in lipid nanoparticles which are taken up by the host cells (Vogel et al, 2020, Jackson et al, 2020). The Pfizer vaccine was tested in healthy adults between the ages of 18-55 and 65-85 years in phase 1 studies and the BNT162b2 vaccine product at a 30 microgram dose was chosen by Pfizer as the lead candidate in phase 2/3 trials (Walsh et al, 2020). The Moderna mRNA-1273 vaccine was tested at three dose levels in those aged 18-55 years and the 100 microgram dose chosen for phase 3 study (Jackson et al, 2020). AstraZeneca COVID-19 vaccine uses a replication deficient chimpanzee adenovirus (ChAd) as a vector to deliver the full-length SARS-CoV2 spike protein genetic sequence into the host cell (Van Doremalen et al, 2020). The adenovirus vector is grown in a human cell-line (HEK293) (see chapter 1). ChAd is a non-enveloped v

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