Regularly in the news since the first cases were identified earlier this year, what does the swine flu epidemic mean for people with HIV in the UK? Gus Cairns has a look.
A: Firstly, it may surprise some people to hear that the number of cases of ‘flu like illness’ notified to doctors plummeted during August.
Flu reports peaked at about 225 new cases per 100,000 population (one case per 444 people) in the week ending 21 July1. Since then flu cases have fallen almost as fast as they rose and as of the week we are writing (week ending 30 August) the number of new cases being reported is about 20 per 100,000. This is still considerably above the average for this time of year, but at present the epidemic is not rapidly increasing.
Seasonal flu tends to peak around Christmas – last year about 45 cases per 100,000 were reported in Christmas week. Some experts are concerned there may be a considerably larger flu peak this autumn, possibly sparked by the return of children to school. The truth is that this new flu virus has surprised us so far and we simply don’t know what it is going to do next.
A: Swine flu is somewhat more contagious than seasonal flu because it’s a new strain and few people have pre-existing immunity. But it doesn’t, thankfully, appear to be more virulent for most people.
We will probably see the same proportion of complications and deaths due to swine flu in people with HIV as that from seasonal flu. Immune suppression may make the complications of flu worse: this especially applies to people with pre-existing lung conditions such as TB, asthma and COPD (emphysema). Because of this people with HIV are amongst the groups entitled to free seasonal-flu vaccination each year.
However flu is not an opportunistic infection: people with HIV are no more likely to acquire flu than the general population, and as long as they don’t get complications, unlikely to die from it.
Seasonal flu particularly affects the people who are classically vulnerable: small children and, in particular, the elderly. The immunosuppressed belong to that group. But a useful analysis in Eurosurveillance journal2 of deaths due to swine flu in the early stage of the epidemic (before July) found that, to quote the paper, “healthy young adults” were the most likely group to die from swine flu with peak mortality in the 20-49 age group.
Ninety per cent of the people whose medical history was well documented, who died with swine flu had another underlying medical condition, with obesity and/or diabetes the most common one. There was also a strong association between pregnancy and swine flu.
“Immunosuppression” was seen in 7% of people who died, but in the people where the cause of immune suppression was known, it was due to things like cancer chemotherapy and transplants and not HIV. Out of the 502 cases documented in the paper, there was not one person known to have HIV.
A: If you think you have flu you should call the National Pandemic Flu Service (NPFS) on 0800 1513 100 or log on to www.pandemicflu.direct.gov.uk.
The general advice is to stay at home, to avoid spreading flu as well as to rest, and to restrict medications to ones for aches and fever such as paracetamol. If it is felt that you have flu you will be offered antivirals, which can be collected by a ‘flu friend’.
If you want to avoid passing it on to people at home, use a tissue when you cough and sneeze, dispose of tissues carefully, ash your hands scrupulously, and regularly clean hard surfaces. Alcohol-based hand rub after touching surfaces can help too. There is no evidence that wearing a face mask will stop you catching flu. There is some evidence that wearing a mask may reduce the chances of you transmitting flu when you’ve very infectious; otherwise the Health Protection Agency only recommends them for healthcare workers.3
Regarding the antiviral pill oseltamivir (Tamiflu) and the inhalation zanamivir (Relenza), their efficacy in reducing symptoms is mild: both reduced the length of time people had feverish symptoms by one to one-and-a-half days out of an average five4,5. They were quite effective at preventing flu, reducing the incidence of other household cases by 70-90%,6,7, but this requires a ten-day course of treatment and obviously involves starting the medicines as soon as one person develops symptoms.
Drug resistance is a problem in flu as it is in HIV. In the last two years the seasonal flu virus has already been almost entirely resistant to oseltamivir, and the first case of resistant swine flu was reported from Denmark at the beginning of July.
For this reason the British Medical Journal8 recently proposed that antivirals should only “still be consideredfor people on medication for asthma, obese people, and pregnantwomen who have been in close contact with probable cases”. However at present people with immunosuppression are entitled to receive Tamiflu, so to obtain it and for more information phone the NFPS.
A: The advice initially is to phone the NFPS as above and not to go to your GP or the hospital. They will advise if you need to seek medical help – though if symptoms are grave, safety is the first priority.
The World Health Organization provides a useful list of symptoms that indicate complications and which should indicate a call to the doctor or to A&E. They include:
Shortness of breath, either during physical activity or while resting
Difficulty breathing
Turning blue
Bloody or coloured sputum
Chest pain
Altered mental state, including drowsiness and confusion
High fever that persists beyond three days
Low blood pressure
In children, warning signs include fast or laboured breathing, lack of alertness, difficulty in waking up, and little or no desire to play.
One or more of the above symptoms could indicate something altogether more serious than swine flu such as TB, pneumonia or a heart condition. So it’s important to get a proper diagnosis.
If your CD4 count is under 200, it is important that you seek advice if you have symptoms of swine flu, particularly if your symptoms are severe.
A: If you have flu you shouldn’t be trying to struggle to the clinic to get your quarterly CD4 count done both for your own sake and because you may infect others.
The NHS is also worried about the impact a serious autumn epidemic could have on health services if a lot of healthcare workers get sick. Contingency plans have been put into place by some commissioners to issue HIV drugs for longer periods in case appointments need to be postponed or drugs cannot be home-delivered on time. It is always a good idea to keep at least one month’s supply of HIV drugs at home. At your next appointment you could discuss having extra supplies.
A: The government has said that people with HIV will be a priority group for swine flu vaccination. As with seasonal flu, you will have to get it from your GP. The first batch of the swine flu vaccine arrived in the UK on 28 August, but is undergoing safety tests by the European Medicines Agency. It is unlikely to be licensed till October.
Whether the vaccine will benefit people with HIV is at present an open question based both on getting more data on safety and more data on whether people with HIV in general or with low CD4 counts are at increased risk.
It’s true that a third of nurses and GPs in two separate polls said they would be reluctant be vaccinated for swine flu, and up to 60% of GPs expressed some doubts based on concerns about it not being safety-tested for long enough,9 but this needs to be put into the context of a traditionally low uptake of seasonal flu vaccine in health workers (about 15%).
It is important at this stage not to draw any conclusions either about what will happen to people who do take the vaccine or what will happen if they don’t. Severe adverse effects caused by vaccines are very rare. The health workers’ stance was controversial because if they get vaccinated they would protect patients as well as themselves. Professor David Salisbury, the Department of Health’s Director of Immunisation, said: 'They have a duty to their patients not to infect their patients and they have a duty to their families.”
For more advice see the NHS website on www.nhs.uk or phone the National Flu Pandemic Service on 0800 1513 100/200.
1. Health Protection Agency: Weekly pandemic flu media update 27 August 2009. See www.hpa.org.uk
2. Vaillant L et al. Epidemiology of fatal cases associated with pandemic H1N1 influenza 2009. Eurosurveillance 20 August 2009.
3. Cowling BJ et al. Preliminary Findings of a Randomized Trial of Non-Pharmaceutical Interventions to Prevent Influenza Transmission in Households. PloS One, early online publication, July 2009. doi:10.1371/journal.pone.0002101
4. Treanor JJ et al. Efficacy and safety of the oral neuraminidase inhibitor oseltamivir in treating acute influenza: a randomized controlled trial. JAMA. 2000;283:1016-1024.
5. Campion K et al. Randomised trial of efficacy and safety of inhaled zanamivir in treatment of influenza A and B virus infections. Lancet. 1998;352:1877-81.
6. Welliver R et al. Effectiveness of oseltamivir in preventing influenza in household contacts: a randomized controlled trial. JAMA. 2001;285:748-754
7. Monto AS et al. Zanamivir prophylaxis: an effective strategy for the prevention of influenza types A and B within households. J Infect Dis. 2002;186:1582-8.
8. British Medical Journal editorial. Who should receive Tamiflu for swine flu? 6 July 2009, doi:10.1136/bmj.b2698.
9. GP Magazine. Exclusive: Most GPs may reject swine flu vaccine. 24 August 2009.
