Julie Lonsdale deputy head of medicines management
Rosalind Way head of research innovation and development
— both at North Lancashire Teaching Primary Care Trust
About this paper
The full paper, together with references and acknowledgements, is available online
Correspondence to: Julie Lonsdale
Swine flu is an illness caused by type A influenza (H1N1) virus. The pandemic of 2009 was caused by a new strain of the virus, Pandemic (H1N1) 2009.
As part of the national pandemic programme North Lancashire Teaching Primary Care Trust opened antiviral collection points (ACPs) for issuing antiviral medicines. A locally enhanced service was offered to community pharmacies to act as ACPs.
The survey was handed out to 1,000 “flu friends” with a request for the patient, or the patient’s representative, to complete the survey following the patient’s recovery.
Results and discussion
Only 28 per cent of respondents had risks or co-morbidities that classified them as being at high risk of complications of influenza.
Symptoms and duration of influenza
The most commonly reported symptoms were tiredness (90 per cent), headache (88 per cent) and sudden fever (82 per cent). All the established symptoms of the H1N1 virus were reported in a high percentage of patients.
Symptom severity reported in the study was mostly quite severe or moderate. Very mild or mild symptoms were only reported in 18 per cent of all respondents. Symptoms were described by the Department of Health as being mostly mild and resembling those of seasonal flu.
Possible reasons why our data conflict with the DoH understanding may be that symptoms became more severe following the initial phase of the pandemic, that patient perceptions of severity differed from those of healthcare professionals or that people with mild symptoms might have chosen not to access the antivirals.
The most usual duration of swine flu illness was between four and seven days. A third of people (32 per cent) returned to their routine activities while symptoms remained. This highlights the need to reinforce the message to patients to stay at home while symptoms remain to limit the spread of the infection. Prevention is the most effective way to reduce the burden and costs of influenza.
Effectiveness of treatment
There was a correlation between the day of receiving the antiviral after symptom onset and the illness duration. The duration of illness was shorter the earlier treatment was received. If received in the first 48 hours the mean duration of symptoms was reduced by 1.2 to 5.1 days.
There was no reduction in illness duration when the antivirals were received three days or more after the onset of symptoms.
Our findings showed that there was no significant difference in the severity of symptoms when the antiviral was started in the first 48 hours of symptoms.
Some 57 per cent of patients did not receive their antivirals until after the first 48 hours of experiencing symptoms. Processes were in place to enable patients to access the antivirals as soon as possible, suggesting that late collection may have been due to patient or flu friend factors.
Patients may have benefited from a clearer message to obtain their antivirals as soon as flu symptoms developed. A one-step approach of authorisation and issue may provide faster access to the antivirals.
Medicines management is about getting the right drug to the right patient at the right time, ensuring that the medicine is effective, necessary, appropriate, timely and safe. Analysis of the data showed that only 31.5 per cent of patients received the antivirals in the first 48 hours and completed the course.
Compliance was shown to be generally good with 86 per cent of patients taking their medicines for five days or more.
Pandemics are a considerable burden to society because of large numbers of people incapacitated by illness. Direct costs relating to hospital admission and treatment occur more frequently in high risk patients.
Additional indirect costs are also substantial and largely attributable to a loss of work productivity. Prevention is the most effective way of reducing costs. Targeted treatment also reduces total costs. The expected benefits of antiviral treatment in a pandemic are:
- Reduction of illness duration and more rapid mobilisation of affected individuals including essential workers
- Possible reduction in hospital admissions of infected individuals with complications
- Reduction of subsequent antibiotic use by individuals with secondary infections
Side effects, patient experiences and perceptions
Less than half of the patients thought they had side effects from the antivirals and the related discontinuation rate was only 1.6 per cent.
Results show that 70 per cent of patients believed that the antivirals helped in some way, however results indicate that the antivirals only reduced the duration of illness when given within 48 hours and do not suggest that symptom severity was reduced.
Our results show that patients’ perceptions of the effectiveness of the antivirals exceeded the evidence.
How people perceive medication assists in their illness affects their compliance and future requests for medication should the need arise again. Of the patients who received the antiviral after 48 hours, 82 per cent thought it assisted their recovery, supporting the idea that patients believe that this antimicrobial medication assists respiratory illnesses despite there being no evidence to support the premise.
As a result of using the National Pandemic Flu Service, 1 per cent of patients who responded to the survey received a misdiagnosis.
The antivirals used in the H1N1 flu pandemic reduced the duration of illness when given in the first 48 hours. There is no evidence to support their efficacy when given after 48 hours of symptoms.
We can conclude that systems put into place for the safe issue of antiviral medicines during the pandemic, including the use of the National Pandemic Flu Service, failed to achieve one of the desired outcomes, namely, getting medicines to patients as early as possible, for most patients.
The results demonstrate that the public may have a poor understanding of how antivirals work. Patients should be given more information on antiviral medication, empowering them to be able to make informed decisions on their treatment.
The most effective way to reduce the costs to society of a flu pandemic is to prevent spread of the disease and to aim to start treatment with neuroaminidase inhibitors as early as possible following the onset of symptoms.