Influenza is a viral infection which attacks the respiratory system.

by icheatboy (student)

Influenza in the UKBiology AS Issue Report

Influenza in the UK

The Influenza problem

According to the UK department of health, “In the UK, about 600 people a year die from seasonal flu. This rises to around 13,000 during an epidemic.” (1) This is a problem that biologists have been and will continue to try and solve, keeping this number as low as possible will save lives.

Influenza is a viral infection which attacks the respiratory system. For healthy people it means a week or two off work with the sudden onset of a fever, headache, cough, sore throat and muscle aches. After about a week these will disappear but you will be left extreme fatigues for a few weeks after you catch the infection. (2) If you are fit and healthy this shouldn’t cause much of a problem. However the problems occur if you have a weakened immune system. This means you are less likely to be able to fight against the virus so you are more vulnerable to catching the virus and its complications, the most likely of which is a bacterial chest infection. This can result in serious illness such as pneumonia which can result in death. (3)

The solution

Currently in the UK a vaccination against influenza is given free of charge to everyone who is in a high risk group. The National Health Service (4) says that this includes all those who are; aged 65 and over, pregnant, suffering with a serious medical condition, living in a residential home or are healthcare workers or carers for the sick or elderly.

Every year the World Health Organisation predicts the three strains of influenza virus that will affect people most and recommends that these are put in vaccines for that influenza season. For example The World Health Organisation (5) states that the vaccination last given out in the UK for the 2010-2011 season contained the; N1H1 strain (Swine flu), H3N2 strain and B strain.

As explained in BBC Focus magazine (6) the vaccination works by containing a small amount of the influenza virus, shown in figure 1, containing the different strains recommended for that year. It is not enough for the body to feel the symptoms of the virus however your body will still respond to the small amount of virus. It produces antibodies, molecules which remember the shape of a protein on the surface of the virus, the hemagglutinin (HA) head. ‘Memory cells’ then remember this shape and if it enters the body again, the antibodies will recognise it and attach themselves to the HA head to kill the virus. This is illustrated in figure 2. As the HA head is a different shape for each strain of influenza and there are different strains circulating all the time, a new vaccine must be made and given to everyone each year so that antibodies suitable for the new strains can be made.

Why is this solution appropriate?

The National Health Service says that “No vaccine is 100% effective; however, people who have had the flu jab are less likely to get flu. If you do get flu despite having the jab, it will probably be milder than if you haven’t been vaccinated.” (7) With the people most at risk from contracting influenza immunised against it, there are significantly fewer cases of the illness. Also the people are vaccinated against it are the people who are most likely to suffer badly from the virus and its complications which can be fatal so the number of deaths related to influenza are also decreased. Even though not all the population is vaccinated against it, it is still less likely for the people in low risk groups to contract the influenza virus because with the high risk population immunised there are fewer people to catch it form as the low risk group are more able to fight the virus quicker and avoid its complications this is a more cost-effective method that vaccinating the entire population.

This is a preview of the whole essay

The UK Health Protection Agency releases a weekly influenza media update; the following statistics are from the statement dated 10 February 2011 (8). 439 people in the UK had died in this winter flu season since October because of the influenza virus. The ages of people for 393 deaths were available have been presented in figure 3. The histogram shows that vaccine is effective for the population in high risk age groups as the number of deaths per the size of each age group is higher in 15 to 64 than the other groups. The majority of this population is not offered the free vaccination while the high risk age groups who are offered the free vaccination have fewer deaths per each year of age, suggesting that the vaccine is effective. In addition to this the update also states that where information was available, 72 percent of fatal cases who were offered the vaccine did not receive it. This further backs up the effectiveness of the scheme as most the people who died of influenza virus are likely to have done so because they did not get their vaccination. Finally the statement says that “Where information is available on the fatal cases, 240 out of 338 (71%) were in a clinical 'at risk' group for vaccination.” (8) As the majority of these deaths are of people in the high risk groups it hints that the vaccination is being given to the correct group of people. This evidence on the high effectiveness of the scheme portrays how the solution is appropriate.

Implications of the solution

Vaccinating such a large percentage of the population for free has a huge economic cost. This is increased when there is a pandemic and emergency vaccinations are given. For example BBC News (9) recently revealed that the department of health spent £239 million on swine flu vaccines. As the strains on the virus are always changing and a new vaccine has to be made every year, the cost of the seasonal influenza vaccinations has to be repeated each year. This is money that could be spent elsewhere in the heath service which is currently undergoing large financial cuts like much of the UK. According to BBC news “More than 50,000 NHS jobs will be lost across the UK over the next five years”. (10) It is likely that the cost of the vaccination is balanced out by the money saved by the National Health Service in having to treat the much greater number of influenza cases that would occur if there was no vaccine. However the cost would be dramatically reduced if the vaccination didn’t have to be repeated each year.

There are however many positive implications of the vaccination scheme. One social benefit is that it means that less people are falling ill. If they were affected by the influenza virus, it would definitely have some level of impact on their daily life. If they are of working age, it is likely that they would have to take some time off work while they recover. This would lead to economic losses for the person involved or their business as they would have to take a day out of earning money or have to pay for a replacement, the vaccine reduces this loss. If not working they may have problems if they are the carer of a child or vulnerable adult as it is likely they will need to find a replacement carer in order to prevent the person they look after contracting the virus. The vaccination highly reduces the chance of this.

Advantages and disadvantages of the solution

As well as the obvious advantage that the influenza vaccination saves lives, there are other advantages of the vaccination scheme. “A three-year study of community-dwelling people aged over 50 found that confirmed flu accounted for about 9% of all respiratory hospital admissions for this group, and that seasonal flu vaccination prevented about 60% of such admissions.” (11) This demonstrates that the vaccine has been successful in reducing the strain on the National Health Service having to treat cases of influenza.

The largest disadvantage of the vaccination scheme is that they have to be repeated yearly in order to keep up immunity from the changing strains on the influenza virus. As well as the financial cost of this some people may not bother to go every year or could have difficulty in getting to somewhere where they can receive the vaccine, practically if they are elderly or disabled. Having to repeat this to every year adds to these problems. Some people may not wish to have the vaccination because they don’t like injections or have heard incorrect stories such as that it can give you the illness. The vaccination is optional so not everyone in the high risk group receives the vaccine and this decreases the effectiveness of the entire scheme. Another disadvantage is that as with most vaccinations there are some side effects to receiving the injection however these are quite small with this vaccine, the National Health Service says “Sometimes, it can cause mild fever and slight muscle aches for a day or so.” (12) Finally, the seasonal influenza vaccine only provided immunity to 3 strains of the virus. These are the three that have been predicted to be the most harmful; however, it is possible to come into contact with another strain of the virus as this is only a prediction. Even if you have had that years vaccination, you with have no immunity against this strain of the virus.

Alternative solutions

Scientists are currently working on a new ‘universal’ influenza vaccination, according to The Telegraph, “A universal flu vaccine that could protect people from all strains of flu has been successfully tested on humans for the first time by Britain scientists.” (13) Focus magazine (6) explains that this vaccination works by targeting the entire HA protein, including the stem which doesn’t change for different strains of the virus as shown in figure 4. This means that the antibodies made will be able to attack any variation of the flu virus. “It is hoped that the vaccination, which is followed by a few booster jabs, will provide life-long immune protection.” (6) This would dramatically reduce the costs of repeating the vaccination scheme yearly and make it a lot more effective. It would also stop flu pandemics which can cause many deaths.

Another alternative to an influenza vaccine is antiviral drugs. These “work by preventing the flu virus from reproducing - to be effective you need to take them within 48 hours of the symptoms beginning. This can reduce the risk of complications and possibly shorten the illness by a day.” (14) This is a good alternative for people who cannot or refuse to have a vaccination for any reason. Tamiflu is the trade name for the drug oseltamivir which was an antiviral drug used to treat the recent swine flu outbreak, it stopped the virus reproducing but caused side effects including; nausea, vomiting, diarrhoea, stomach ache and headache according to Yougov. (14) The official website for Tamiflu (15) states that there is a 30% reduction in the duration of the illness if the drug is taken. This figure was derived from a clinical trial that took place in 1998, it compared the duration of the illness in 629 unimmunised adults who had taken either Tamiflu or a placebo. The results are illustrated in figure 5.

Conclusion

Influenza is a common but serious illness in the UK. The current scheme to vaccinate the people at high risk of contracting the virus is working well however the vaccine has to changed each year due to differing strains of the virus. However a new vaccination is currently in development which will provide immunity from all strains of the influenza virus.