For most people, having the flu just means a couple of days in bed.
But for a significant number particularly children, the elderly, and those with other conditions it is a lot more serious.
The average flu season in the US kills around 41,000 people, experts reckon. And in a bad year, things can get much worse. During the last big UK epidemic in 1999-2000, so many staff got sick, that hospitals had to cancel vital operations.
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While a vaccine has been widely available since the 1940s, it has to be taken every year, and provides only partial protection in any case.
The good news is that both biotech and pharmaceutical companies are working hard to find a better version. And that spells opportunity for adventurous investors.
The trouble with flu vaccines
The trouble is, there are many different variants of the flu virus, and new ones appear each year. Meanwhile, the number of antibodies the body produces drops in half within about six months of each jab. That's why people have to be re-vaccinated each year.
To make matters worse, the vaccine takes time to produce. This means that the companies that make it have to decide on which strains to guard against long before flu season peaks in the winter. The World Health Organisation gives them the best advice it can, but mismatches still occur. That means that in some cases, that year's flu jab might provide only partial protection, or even none at all.
Even when the viruses are well matched to the vaccine, protection is not complete. A recent study suggested that in a good year, the vaccine reduces the number of cases in healthy adults by about two-thirds. The benefit for the elderly is much smaller.
To get around this, flu vaccine manufacturers have been taking two main approaches. One is simply to increase the number of strains in the jab. This year a number of firms are including four strains, rather than the three commonly used.
However, several are trying instead to find the Holy Grail': a universal vaccine, which will provide much broader protection.
The growing market for flu vaccines
As a result, some countries such as the US recommend that as many people as possible get the jab. And after the 2000 epidemic here in the UK, the NHS decided to provide free flu jabs to all over-65s. This has gradually been extended to other groups: pregnant women became eligible in 2010. The government now aims to provide it to all two- and three-year olds as well.
At the same time, hospitals have been strongly encouraged to vaccinate key staff. Indeed, £500m of NHS funding has been made conditional on NHS trusts getting 75% of their staff to have a jab.
There are even suggestions that flu vaccination could benefit developing countries. According to the United Nations, the biggest childhood killer in these countries is pneumonia, a third of which can be attributed to the flu. Last year, the World Health Organisation started to organise global distribution of swine flu jabs. Overall the global flu jab market is expected to grow from $2.9bn in 2011 to $3.9bn by 2018.
This firm is well-placed to profit
In the case of Inovio's flu jab, this platform allows it to identify the bits of the virus that are common to all strains. It can then genetically engineer a version that allows the body's immune system to react to all types of flu.
Inovio's flu vaccine is still going through early stages of clinical trials. However, the preliminary results are very encouraging. The latest data, revealed in the spring, suggests that the broad jab provides equivalent protection to a conventional vaccine that is perfectly matched with a particular strain.
Better yet, the SynCon process isn't just limited to flu vaccines. Inovio is also testing an HIV vaccine and treatments for several cancers. While none has reached the market yet, drug giant Roche has signed a licensing deal, worth up to $400m, for global rights to prostate cancer and hepatitis B vaccines from Inovio. The $10m upfront cash should help Inovio fund its research.
As with all drug companies at the more experimental end, Inovio is risky. But it's a very promising-looking play on an exciting area. I also recently covered how vaccines are being used to treat deadly conditions such as lung and brain cancer. And if you're interested in biotechnology, Dr Mike Tubbs has also looked at other flu jab makers in his Research Investments newsletter find out more about it here.
Research Investments is a regulated products issued by Fleet Street Publications Ltd. Your capital is at risk when you invest in shares, never risk more than you can afford to lose. Please seek independent financial advice if necessary. Fleet Street Publications Ltd. 0207 633 3600.
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Matthew graduated from the University of Durham in 2004; he then gained an MSc, followed by a PhD at the London School of Economics.
He has previously written for a wide range of publications, including the Guardian and the Economist, and also helped to run a newsletter on terrorism. He has spent time at Lehman Brothers, Citigroup and the consultancy Lombard Street Research.
Matthew is the author of Superinvestors: Lessons from the greatest investors in history, published by Harriman House, which has been translated into several languages. His second book, Investing Explained: The Accessible Guide to Building an Investment Portfolio, is published by Kogan Page.
As senior writer, he writes the shares and politics & economics pages, as well as weekly Blowing It and Great Frauds in History columns He also writes a fortnightly reviews page and trading tips, as well as regular cover stories and multi-page investment focus features.
Follow Matthew on Twitter: @DrMatthewPartri
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