Novel Influenza A H1N1 2009

INFORMATION PACK – AUGUST 2009

COVER PAGE

Primary TAG Information Pack – August 2009

In order to ease general practice paper burden, from this point forward we will be circulating:

  • A monthly ‘Novel A H1N1 2009 Information Pack’
  • Updates to specific information contained in this information pack - as required

Please disregard ALL previous Novel Influenza H1N1 advisories from around your practice... this will eliminate problems associated with out of date information.

Primary TAG Information Pack – Advisory 5thAugust 2009

This information pack is separated into 4 sections, with separate sections including:

  1. SECTION ONEDiagnosis and clinical aspects of Novel Influenza A H1N1 09

Up to date, 5th August 2009

a)Swabbing of cases is no longer necessary

b)Support available

c)Local status update

d)Clinical aspects

e)Aspects of treatment

  1. SECTION TWOSpecial populations

Up to date, 5th August 2009

a)Infants and Children

b)Pregnant women

  1. SECTION THREEManaging cases

Up to date, 5th August 2009

a)Instructions for accessing crown stocks of Tamiflu – Up to date, 5th August 2009

b)How to prescribe from the crown stock pile - Up to date, 5th August 2009

c)Dosage information – Up to date, 5th August 2009

  1. SECTION FOUR Forms and pharmacies

Up to date, 5th August 2009

a)FORM – Request for Tamiflu - Up to date, 5th August 2009

b)Community pharmacies authorised to dispense – Up to date, 5th August 2009

  1. SECTION FIVESummary for clinicians

Up to date, 5th August 2009

a)As provided by the ESR to 26th July 2009

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COVER PAGE

Novel Influenza A H1N1 2009

INFORMATION PACK – AUGUST 2009

SECTION ONE - Diagnosis & clinical aspects ...5th August 2009

a) Swabbing of cases is no longer necessary

Laboratory testing (viral swabs) for Novel Influenza H1N1 09 is not generally required for clinical care. Laboratories will not test unauthorised swabs.

b) Support available to general practice

In addition to the support of the ODHB Primary TAG, your PHO and the Medical Officers of Health, general practice is supported by:

  • Public Health South will focus on managing high risk clusters, monitoring, surveillance and supporting measures to reduce community transmission. Please inform Public Health South and your PHO about any outbreaks in institutions/groups.
  • The DHBs is investigating the establishment of an Otago/Southland “0800” telephone triages service for the public once the workload warrants it.
  • The National GPs phone line has been discontinued.

For current information visit:

Ministry of Health

World Health Organisation.has the key role for managing cases of influenza. Please;

ESR Public Health Surveillance Report

c) Local Status Update

  • General Practice has the key role for managing cases of influenza. Please;
  • See patients as you normally would, keeping good infection control around patients with influenza
  • Remain vigilant for other diseases such as meningococcal disease
  • Keep your PHO informed about your workload with the fax back form as requested
  • Encourage people with mild illness to care for themselves at home and remind all influenza cases to isolate themselves at home until free of symptoms.
  • Be prepared for increasing levels of illness
  • Identify someone [ and an alternate] to lead the response in your practice and to be main point of contact for all information and enquiries and tell your PHO who those contacts are
  • Identify a “buddy practice” should you experience workload difficulties
  • July saw most practices becoming increasingly busy with Influenza like illness [ILI] presentations. As we are in the “management phase” of the pandemic response, swabs were not routinely taken and therefore accurate numbers of H1N1 are not known, although extrapolation from Surveillance practice figures would suggest that more than 70-80%of influenza in the community is Novel A H1N1 09. All practices reported that they were coping with the increased workload.
  • Information through TV, radio and print media clearly advised the public about managing ILI and for the most part communities have responded appropriately.
  • In the early part of July secondary and tertiary services in Southland and Otago also experienced an increase in presentations, admissions and staff sickness, reflecting what was happening in Primary care.
  • Student health services reported high levels of illness in students and schools were also experiencing increasing absences due to ILI.
  • The last two weeks of July and the beginning of August have not seen exceptional levels of illness for this time of year, perhaps because of the school holidays. However there have been a number of patients in Otago and Southland with severe illness requiring ICU care.
  • Practices have noted that younger age groups have been more severely affected, with many presenting back to their GP a week after apparently recovering from their ILI.
  • Unfortunately we are unable to predict what may happen in the coming weeks. The response has had the desired effect of “flattening” the incidence curve, but we are not clear where we are on that curve. The Ministry of Health has indicated that we need to be prepared for the possibility that our preparations should take us through until the end of the year.
  • Regular feedback from practices is much appreciated, as is the extra effort required to attend meetings and teleconferences.

d) Clinical Aspects of H1N1 09

Globally, H1N1 09 appears to mainly present as uncomplicated influenza, so far affecting mainly younger people. There is early evidence suggests that people over 55 who have been exposed to 1957 influenza may have some protection against the novel influenza strain.

A variety of clinical syndromes have been described for novel influenza:

  • Illness and death in the young and sometimes previously healthy at a rate in excess of that seen with seasonal influenza
  • Vomiting and diarrhoea is seen with all types of influenza (including type B) but may be more common in novel influenza
  • Severe pneumonia and rapid progression to respiratory failure. Patients with pre-existing lung disease such as asthma are particularly prone.
  • Severe disease in the immune compromised
  • Severe illness and foetal death in pregnant women
  • Tendency to develop Lower Respiratory Tract Infections (LRTI) with a greater frequency than seasonal influenza.
  • Severe disease in morbidly obese patients, with a higher than expected death rate.
  • There has been speculation that the mortality rate is 0.5% of laboratory-confirmed cases. However this may be an over-estimate as many people with milder disease may never seek medical advice or be tested

Additionally, the following has been noted in New Zealand:

  • Possible pulmonary haemorrhage as a complication
  • Prolonged intubation/ventilation requirements even in previously healthy patients.
  • Mucopurulent sputum and haemoptysis have been observed with greater frequency than is generally seen in patients with LRTI in DunedinHospital this winter – unclear if all of these patients have H1N1
  • It is possible that H1N1 09 pneumonia may not present as classic influenza (or other viral) pneumonia

e) Aspects of Treatment during the 2009 Pandemic

  • Usual dose of Oseltamivir (Tamiflu) is 75mg (one capsule) po BD (Dose reduce in renal impairment).
  • Usual dose of Oseltamivir (Tamiflu) is 75mg (one capsule) po BD (Dose reduce in renal impairment. For further dose information, including paediatric dosages please refer section 3.
  • Consult with secondary/tertiary care centreearly where clinical concern for unusual and/or rapidly progressive LRTI, especially in immune compromised/pregnant individuals.
  • Treat presumptively during the Pandemic period.
  • Immune compromised individuals suspected of having Influenza, in particular those with pre-existing respiratory disease (i.e. Asthma, COPD), should be treated for H1N1 09 presumptively
  • Exposures and/or clinical illness involving women who are or recently were pregnant should be treated presumptively in all trimesters. Safety data for Tamiflu in pregnancy are not established, but no adverse effects have been reported either to mothers or exposed infants. See product information sheet for more information.
  • Clinical benefit of Oseltamivir is seen if treatment commences within 48 hours of onset of symptoms. Later treatment and/or higher dosages of Oseltamivir may be useful in immune compromised individuals but there is no trial data. Prophylaxis (Tamiflu 75mg OD) should be considered for immune compromised individuals who have had a contact with proven H1N1 infection or a highly suspicious ILI.
  • NZ surveillance data (including Otago) indicate that the majority (70-80%) of current influenza infections are caused by the pandemic strain H1N1 09. This is especially true in the Otago region. To date no Oseltamivir (Tamiflu)-resistant H1N1 09 has been identified in NZ. All tested specimens of seasonal Influenza A are resistant to Oseltamivir however, in line with the northern hemisphere non-pandemic Influenza A strains.

Secondary Bacterial Pneumonia

The incidence of secondary bacterial infections is unknown. The group of bacterial agents causing secondary pneumonias is likely to include Streptococcus pneumoniae and/or Staphylococcus aureus. It may be difficult to confidently diagnose bacterial pneumonia in some patients, given the unusual nature of some H1N1 09 pneumonias. However, sputum and blood cultures should be obtained for all patients with suspected bacterial pneumonia.

In uncomplicated ILI (Influenza-Like Illness) patients suspected of bacterial LRTI, empiric antibacterial treatment (Augmentin (Amoxycillin/Clavulanic acid) or Cefaclor is reasonable in the outpatient setting.

Encouraging Influenza and Pneumococcal vaccination in those for whom it is recommended (i.e. Smokers, chronic lung disease patients) is particularly important ahead of possible future Pandemic waves. Smoking cessation may well reduce the risk of serious pneumonia from any cause, especially pneumococcal pneumonia.

SECTION ONE1

Novel Influenza A H1N1 2009

INFORMATION PACK – AUGUST 2009

SECTION TWO – Special population cases...5th August 2009

a) Special Population - infants and children

Influenza presents in infancy and childhood as a wide variety of clinical syndromes.The diagnosis needs to be considered and if any suspicion of influenza exists, appropriate precautions taken to prevent spread.Presentations may include:-

  1. Fever and misery
  2. Bronchiolitis
  3. Asthma exacerbation
  4. Acute otitis media
  5. Lower respiratory infection
  6. Convulsion with fever
  7. Dehydration
  8. Fever, lethargy, irritability meningitis not excluded
  9. Toxic bacteraemic type illness
  10. Apnoea
  11. Diabetic instability

The focus of care needs to relate to the presenting clinical syndrome and be managed appropriately.Consult relevant clinical guidelines.

Wherever possible infants and children with uncomplicated influenza should not be seen in hospital or admitted. Thresholds for admission may be lowered where underlying conditions exist:-

infants under 6 months

infants with a history of prematurity especially if any ongoing lung disease

immunosuppression

children with cerebral palsy or weakness that may impair coughing

underlying heart disease

lung disease

b) Special Population – pregnant women

Pregnant women appear to have higher rates of hospitalisation with influenza. Fever in the first trimester is associated with twice the rate of neural tube defects in the foetus. Therefore both antipyretics and antivirals may be useful.

Influenza close to the time of delivery poses extra challenges for maternal and newborn health, as well as challenges to infection prevention in the delivery suite.

The Ministry’s Pandemic Influenza Technical Advisory Group recommends early administration with either oseltamavir (Tamiflu) or Zanamavir (Relenza) when indicated.Neither medicine is contraindicated during pregnancy, however there is limited information related to their use. Whereas preclinical studies suggest that the risks are low, their potential to cause foetal toxicity or malformations in humans is currently unknown; therefore it is recommended that they should be used during pregnancy only if the potential benefit justifies the potential risk to the foetus. A local obstetric or infectious diseases specialist should be consulted where there are concerns.

SECTION TWO1

Novel Influenza A H1N1 2009

INFORMATION PACK – AUGUST 2009

SECTION THREE – Managing cases of H1N1 09 ...5th August 2009

a) Instructions for doctors wishing to access the Crown stockpile of Tamiflu during the “manage it” phase of pandemic influenza

1) General Practice role under “Manage It”

  • General Practice has the key role in managing cases of Novel A Influenza
  • Most people will recover at home without the need for a GP visit
  • Please see all those who are ill (including for influenza ) as you normally would
  • There is no need for routine swabbing

2)General Practitioners and Hospital doctors will be able to access the Crown stockpile of Tamiflu via authorised community pharmacies (list attached) for patients meeting clinical and eligibility criteria.

3)Treatment should begin within 48 hours of symptom onset. Treatment effect is minimal if started after 48 hours.

Clinical criteria – case definition of Influenza

Sudden onset of respiratory illness with fever > 38C, chills, AND sore throat or cough, or aching muscles / headache.

NB Influenza presents in infancy and childhood as a wide variety of clinical syndromes - see Paediatric clinical guidelines

Eligibility criteria

Tamiflu from the Crown stockpile can only be used for the following:

  1. Patients with severe clinical influenza-like illness, regardless of whether they are admitted to hospital or not.
  1. Hospitalized patients with upper or lower respiratory tract symptoms
  1. Symptomatic people at high risk of influenza-related complications –
  • People who are immune compromised or suppressed (transplantation, haematological and solid organ malignancy on chemotherapy/radiotherapy, HIV, autoimmune disorders, etc)
  • Anyone over 12 months of age with chronic medical conditions, such as:
  • Severe or poorly controlled congestive heart failure
  • Severe chronic respiratory disease
  • More severe asthmatics (e.g. people on oral steroids, high dose steroid inhalers, or steroids and long-acting beta-agonists)
  • Renal replacement therapy.

NB Dosage adjustment is required for people with renal impairment, discuss with their specialist.

  • Women who are pregnant
  1. People who live or work in ‘high risk’ institutions, or as part of cluster and/or infection control, where appropriate – discuss with Medical Officer of Health.
  1. Tamiflu is not licensed for children under 12 months. Severe disease in children of any age needs to be discussed with a paediatrician.
  1. The Ministry of Health does not currently recommend the routine use of antivirals for pre- or post-exposure prophylaxis. Situations where post-exposure prophylaxis may be indicated e.g. for essential workers and hospital staff where there have been significant breaches of Personal Protective Equipment should be discussed with the Medical Officer of Health.

b) How to Prescribe from the Crown Stockpile

Step 1

If the person meets the clinical and eligibility criteria, complete the “Request for Tamiflu” form [copy below] and fax to Public Health South (03) 476 9858, then initiate step 2 without waiting for a reply.

Step 2

Prescribe Tamiflu for patient on your normal prescription pad and add ‘notified to Medical Officer of Health

  • Tell patient they can only fill the script at an authorised pharmacy – attached list.
  • Clear documentation is required of the person’s illness. You must confirm they meet the clinical and eligibility criteria as per the “Request for Tamiflu” form.
  • Pharmacies will send a copy of the prescription to Public Health South for cross checking with the “Request for Tamiflu” form. The DHB or the Ministry of Health can audit the process.
  • There is no patient pharmacy fee for crown stockpile medicines

Step 3

To minimise transmission in pharmacies:

  • Ask the patient if a well person can collect their prescription from an authorised pharmacy. If so fax it to the pharmacy.
  • If the sick patient has to go to the pharmacy the doctor should provide them with a surgical mask to wear in the pharmacy while they collect the script.

c) Dosage information - TAMIFLU (5th August 2009)

Developed by- Dr Antje van der Linden – Consultant Microbiologist and Dan Wright- Medicines Information Pharmacist

Dose (treatment) / Comments
Adults and children ≥ 13yrs and > 40 kg / 75 mg capsule twice daily for 5 days
Creatinine clearance 10-30 mL/min / 75 mg capsule once daily for 5 days
Children >1 year and under 13 years or those unable to swallow capsules / >40 kg / 1 capsule (75mg) mixed with a sweet food twice daily for 5 days / See instructions for mixing capsules with food below
15-40 kg / 2/3 (two thirds of) capsule (50 mg) daily for 5 days / See instructions for giving part capsules below
 15 kg / 1/3 ( one third of) capsule (25 mg) twice daily for 5 days / See instructions for giving part capsules below

* oseltamivir is not registered for use in children < 1 year but if there are concerns, please discuss with the on-call Paediatrician

Instructions for mixing oseltamivir with sweet food

Acceptable sweet foods include: smooth textured jams, fruit syrup, strongly flavoured runny honey, strong sugar syrup, golden syrup and sweetened condensed milk. DO NOT USE CHOCOLATE SYRUP

  1. Place a large teaspoon of some strongly flavoured sweet food* into a clean small bowl.
  2. Carefully twist and pull apart the oseltamivir capsule, and pour the contents into the food.
  3. Stir thoroughly for at least one minute until all the powder is completely mixed in.
  4. Divide the mixture into equal halves or thirds and give the prescribed portion (i.e. ½ = 50mg, 1/3 = 25mg etc). Discard the unused portion.
  5. It has a bitter after taste and taking a strongly flavoured drink afterwards may help.

SECTION THREE1

Novel Influenza A H1N1 2009