Immunisation against infectious disease Updates Chapter 23a Pandemic influenza A(H1N1)v 2009 (swine flu)

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1 Immunisation against infectious disease Updates Chapter 23a Pandemic influenza A(H1N1)v 2009 (swine flu) p.1 Chapter title Delete (swine flu) p.2 History and epidemiology of the disease Replace second paragraph with: As of 20 September 2009, human infections with the new virus have occurred in 191 countries worldwide including the UK (WHO, 2009). In the UK, the number of reported cases increased rapidly in June and early July 2009 with the first wave peaking in late July 2009 (Figure 1). The number of cases then fell although the level remained above the summer norm. In September 2009, the number of cases started to increase again reaching a peak during November and then falling gradually. Figure 2 shows the number of GP consultations for influenza-like illness per 100,000 population in England, Wales, Scotland and Northern Ireland. Replace third paragraph with: Children and young adults appear to be most susceptible to clinical infection with the highest incidence in 5-9 and year olds (Figure 3) with a smaller number of cases in adults older than fifty years of age (born before 1957). The low number of cases seen in those aged over fifty is thought to be due to previous exposure in this age group to similar strains of H1N1 that circulated between 1918 and 1957 (Hancock et al., 2009). This pattern is confirmed amongst the deaths from confirmed influenza A (H1N1)v infection. By 11 December 2009, 85% of deaths (n=185) reported in the UK had been in patients less than 65 years of age, with 69% of these (where information was available) reported to have an underlying risk factor. Those with underlying neuro-developmental problems were at particularly high risk of severe outcome compared to the general population (Source: HPA).

2 p.3, Replace Figure 1 with: ILI rate per ILI 100,000 rate per 100, First UK cases detected First UK cases detected 19-Apr 31-May 2008/ / / /10 Baseline* Epidemic threshold* 2008/ / / /10 NPFS launched and Baseline* Epidemic threshold* schools close for Summer Swi NPFS ch to launched and schools treatment close for Summer only phase Schools re-open Switch to treatment only phase Schools re-open School half-term break School half-term break 12-Jul 23-Aug 4-Oct 15-Nov 27-Dec 7-Feb 21-Mar Week-ending date Figure 1 Weekly incidence of ILI/ , England and Wales (source: RCGP/HPA) * Baseline: 30 per 100,000; epidemic threshold=200 per 100,000; NPFS=National Pandemic Flu Service Replace Figure 2 with: Rate per 100,000 population England (RCGP) Northern Ireland (CDSC) Scotland (HPS) Wales (NPHS) Week Figure 2 GP weekly consultation rates for influenza/ili in the UK national sentinel influenza schemes, 2009/10 RCGP=Royal College of General Practitioners; NPHS=National Public Health Service; HPS=Health Protection Scotland; CDSC=Communicable Disease Surveillance Centre.

3 p. 6, Presentation Pandemrix Replace paragraph numbered 1. with the following: Instructions for mixing Pandemrix (see Figure 4) are: 1. Take one vial of vaccine antigen out of the larger box and one vial of adjuvant suspension out of one of the smaller boxes. Return the boxes to the fridge. Mark the larger vial containing the vaccine antigen with the date, time and the initials of the immuniser immediately before mixing the vaccine. p. 7, Replace paragraph numbered 5. with the following: obs, sca ccin 5. The mixed vial now contains ten (0.5ml) doses of vaccine. If there has been no wastage some vaccinators may be able to withdraw eleven doses from the vial. Dosage and schedule Replace second paragraph with: Pregnant women should be offered Pandemrix in preference to Celvapan. This is because a one-dose schedule of Pandemrix gives adequate levels of antibodies and thereby confers more rapid protection than would be afforded by the two-dose Celvapan schedule at a time when pandemic influenza viruses are circulating. p. 8, replace existing table with table below. Age Pandemrix Celvapan Children from six Immunocompetent: Two doses of 0.5ml months to ten years A single dose of 0.25ml. given at least three of age Immunocompromised: weeks apart. Two doses of 0.25ml given at least three weeks apart. Children aged ten Immunocompetent: Two doses of 0.5ml years and over or A single dose of 0.5ml. given at least three adults Immunocompromised: weeks apart. Two doses of 0.5ml given at least three weeks apart. Individuals who are immunocompetent and who have already received one dose of Pandemrix do not need a second dose of Pandemrix even if this has already been scheduled. Immunocompromised individuals should still receive a second dose as scheduled.

4 Administration Replace the third paragraph with: The influenza A(H1N1)v vaccine can be given at the same time or at any interval before or after any other vaccines including seasonal influenza vaccine and routine childhood vaccines. Vaccines should be given at separate sites, preferably in different limbs. p.9, Replace the second paragraph with: The site at which each vaccine is given, the vaccine product name and the batch numbers of the vaccines should be recorded in the individual s records and on the patient s appointment card. For Pandemrix the batch number on the outer box is the number that should be recorded. p.10, Add the following under Table 1. Clinical risk category Chronic respiratory disease, asthma Chronic heart disease Examples (decision based on clinical judgement) Chronic obstructive pulmonary including disease, disease (COPD) including chronic bronchitis and emphysema; bronchiectasis, cystic fibrosis, interstitial lung fibrosis, pneumoconiosis and bronchopulmonary dysplasia (BPD). Asthma that requires continuous or repeated use of inhaled or systemic steroids or with previous exacerbations requiring hospital admission. Children who have previously been admitted to hospital for lower respiratory tract disease. Congenital heart disease, hypertension with cardiac complications, chronic heart failure, individuals requiring regular medication and/or follow-up for ischaemic heart disease. Chronic renal disease Chronic renal failure, nephrotic syndrome, renal transplantation. Chronic liver disease Cirrhosis, biliary atresia, chronic hepatitis. Chronic neurological Stroke, transient ischaemic attack (TIA). disease Diabetes requiring insulin or oral hypoglycaemic drugs Immunosuppression Type 1 diabetes, type 2 diabetes requiring oral hypoglycaemic drugs, and diet controlled diabetes. Immunosuppression due to disease or treatment. Patients undergoing chemotherapy leading to immunosuppression. Asplenia or splenic dysfunction. HIV infection at all stages. 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 (any age) or for children under 20kg a dose of 1mg or more per kg per day. However, some immunocompromised patients may have a suboptimal immunological response to the vaccine. The examples within each group are not meant to be an exhaustive and exclusive list. It is not possible to list all conditions likely to be at higher risk. Healthcare practitioners should also use clinical judgement and take into account the risk of influenza infection exacerbating any underlying disease that a patient may have, as well as the risk of serious illness from influenza itself. A set of Read Codes has been developed by PRIMIS+ to support identification of the at-risk groups in primary care. This set of codes is also not exhaustive and should be used in conjunction with clinical judgement. The codes can be obtained at: Vaccinationprogramme/DH_107355#_9

5 p.11, Insert the following after the first paragraph: The groups have been prioritised for vaccination in the following order: i. Individuals aged six months and up to 65 years in the clinical at-risk groups (see Table 1) ii. All pregnant women iii. Household contacts of immunocompromised individuals iv. Individuals aged 65 years and over in the clinical at-risk groups (see Table 1) p.12, Pregnancy and breast-feeding Replace first paragraph with: All pregnant women should be vaccinated as they are at increased risk of complications from influenza A(H1N1)v. A study of over 2000 pregnant women who received influenza vaccine demonstrated no associated adverse fetal effects (Heinonen et al., 1973). There is no evidence of risk from vaccinating pregnant women, or those who are breast-feeding, with inactivated viral or bacterial vaccines or toxoids (Plotkin et al., 2009). Replace second paragraph with: Pregnant women should be offered Pandemrix in preference to Celvapan as this vaccine appears to give adequate levels of antibodies after a single dose thereby conferring more rapid protection. p.13, Adverse reactions Insert after first paragrapgh: Fevers over 37.5 C are common in children and are usually mild. Higher rates of fever have been observed in children aged 6-35 months following the administration of a second dose of Pandemrix in some studies. As with all childhood vaccinations advice on the use and appropriate dose of paracetamol or ibuprofen liquid to treat a fever should be given at the time of immunisation. Local reactions are usually self-limiting and do not require treatment. If they appear to cause discomfort, then paracetamol or ibuprofen can be given.

6 p 14, Celvapan Replace third paragraph with: A recent study in the UK found that there is no association between Guillain- Barré syndrome (GBS) and seasonal flu vaccines although there is a strong association between GBS and influenza-like illness (Stowe et al., 2009). The increased risk of GBS after influenza-like illness, if specific to infection with influenza virus, together with the absence of a causal association with influenza vaccine suggests that influenza vaccine may reduce the overall risk of GBS. GBS has been reported very rarely after immunisation with influenza vaccine (one case per million people vaccinated in one US study) (Lasky et al., 1998). In 1976, a cluster of GBS cases was reported in association with the swine flu vaccines used in the United States. The exact reason why the 1976 vaccine appeared to increase the risk of GBS remains unknown, but it was estimated that around one extra case of GBS occurred for every 100,000 doses of vaccine given (Schonberger et al., 1979). Surveillance of GBS following influenza A(H1N1)v infection and vaccination has been established through the British Neurologists Surveillance Unit (BNSU) and the British Paediatric Surveillance Unit (BPSU). Current data suggest, however, that the benefits of vaccination will outweigh any risk of GBS and therefore, subject to the clinician s discretion, those who have had a previous episode of GBS can be vaccinated. p.16, Vaccines Replace first paragraph with: In England, pandemic influenza A(H1N1)v vaccine will be supplied as detailed in the letter issued 15 October by Sir Liam Donaldson, Chief Medical Officer, Professor Christine Beasley, Chief Nursing Officer, Dr Keith Ridge, Chief Pharmaceutical Officer. Details can be found at: Dearcolleagueletters/DH_ p.16, References Insert in alphabetical order: Heinonen OP, Shapiro S, Monson RR et al., (1973) Immunisation during pregnancy against poliomyelitis and influenza in relation to childhood malignancy. Int J Epidemiol 2: