Chester Clinic

 

Issues 75

vulnerable versions. Dr Catherine Bennett of the University of Melbourne grimly informs us: "Today up to 95% of the bacteria causing common skin infections (e.g. boils) are penicillin-resistant" (see pp.22–24).
The problem, however, is not just with the diseases.
Stephen Luntz, Editor, Issues
Chlamydia can be cured with a dose of antibiotics, but 100 million new cases (and rising) appear each year partly because people fail to get themselves checked before passing Inthe 1950s and ‘60s there was optimism in the air – it on.
medical science had disease on the run. Diseases like Furthermore, rates of AIDS, chlamydia and many other cancer might still have been a problem, but with peni- diseases would plummet if we practised safer sex, but not cillin putting bacterial disease to flight and vaccinations everyone does. As Heather Corinna of www.scarleteen.com controlling polio and small pox it seemed like only a matter explains: "Plenty of young adults have the idea that condoms of time before infectious diseases would be wiped out, along put ‘something between' them and their partner" (see with many other conditions.
pp.25–29). "A pregnancy and child absolutely puts something Now the opposite is the case – governments around the in the middle, as does a sexually transmitted infection." For world are in a race to stock up on supplies of Tamiflu before a lot of diseases the problem is not that we lack solutions, it's an outbreak of avian influenza can cause millions of deaths.
that so many of us fail to think sensibly about using those AIDS is killing similar numbers more slowly in the devel- that we have.
oping world and, despite plenty of new drugs and superb The problem is not just at an individual level. Although public health campaigns, keeps coming back even in wealthy no cure for AIDS exists, great work has been done to create drugs that dramatically extend the lives of people infected with What went wrong? The answer is many things. One HIV. By reducing the viral load in a person's body, these drugs problem is that many of the diseases are much more slip- also reduce the risk that someone who is taking them will pery than we thought. infect everyone else.
Influenza is the perfect example. As each new strain comes However, James Nichols of Médecins Sans Frontières along we can produce a vaccine to protect people, but nothing (MSF) points out: "Even today, 95% of the [AIDS] drug market stops the disease mixing and matching its surface features to is in the developed world, yet 95% of patients live in Africa, find new ways past our immune systems. In most cases a Latin America and Asia" (see pp.30–35).
new ‘flu variety does some damage before the vaccine can be MSF's programs make antiretroviral drugs available in created, but it is usually only fatal for those who are already limited areas. These projects demonstrate that answers are possible, but the failure of the rich world to provide the money However, when a really new variety of ‘flu comes along we has meant that the disease runs unchecked across most of lack the immunity acquired by having encountered some- Africa and large parts of Asia.
thing vaguely similar. If the virus is particularly potent it can As if our neglect was not bad enough, we face the danger kill even the strongest people, as the pandemic of 1918–19 did.
that people will deliberately choose to infect each other with Sure we'll produce a vaccine in a few months, but ‘flu spreads diseases as a method of war or terrorism. Stephen Leeder so fast that tens of millions could be dead by then. and Anne-Marie Boxall of the University of Sydney point out Other diseases, such as AIDS resist simple vaccines in the that biological warfare is not new. "In the 15th century, during first place. In May 2006 the University of New South Wales Pizarro's conquest of South America, he improved his chances started enrolling people in a trial of an anti-AIDS vaccine.
of victory by presenting gifts to the natives – clothing laden However, there have been plenty of vaccines tried before with smallpox virus" (see pp.39–40).
against HIV, with little success. Even if one "works" it is more Now, however, bioterrorism can cause chaos even without likely to reduce infection rates a little rather than offering killing many people. "The consequences of bioterrorism often the almost complete protection that vaccines can offer against have nothing to do with the biological agent used and every- simpler diseases. thing to do with public panic and the need for community Even some of the diseases we thought we had beaten are leaders to be seen to be ‘doing something'," Leeder and Boxall reappearing as natural selection ensures that those bacteria with resistance to antibiotics spread to take the place of the The definition of emerging diseases is not entirely clear.
75 JUNE 2006
Some people apply it only to new and expanding infectious So far the H5N1 variety hasn't managed to spread from diseases, while others include any diseases that are becoming person to person, and jumps poorly from birds to humans.
However, other flu viruses have no problems travelling from We've used the latter interpretation, considering two one human host to another, and flu viruses share a fright- diseases that have increased dramatically in recent decades ening ability to interchange DNA, so just one person infected – asthma and RSI. Although both seem to have levelled off with both a normal dose of flu and with the avian variety recently they're interesting because we don't fully under- could start a pandemic such as the one that killed more people stand the factors that have influenced their frequency. As Dr than World War 1.
John Woods and Prof Philip Thompson note: "The under- For a time the world shut its eyes and pretended that the lying reasons why some people develop asthma are still poorly problem would go away, but recently governments and indi- viduals have been waking up. Wealthy nations are stocking There are other emerging diseases where our under- Relenza and Tamiflu, two drugs that protect against, and standing is better. Rates of Type II diabetes are shooting up, reduce the severity of, flu.
mainly as a result of our diets and lack of exercise (see Issues The need for such stocks is so widely acknowledged. It's less well-known that both drugs are based on research uncov- Sometimes we do manage to stop diseases emerging.
ering the structure of the flu virus by Prof Graeme Laver of Variant Creutzfeld Jacob disease (CJD) appeared as a result of people eating meat from animals with "mad cow disease".
the Australian National University. Laver identified sections The disease attracted plenty of attention, partly because it is of the virus' surface that don't change, enabling the produc- so horrific and also because the infectious agent, known as tion of drugs that prevent the virus from escaping infected a prion, is so bizarre.
However, since it was realised that mad cow disease However, Laver doubts that the Australian government resulted from the truly mad behaviour of turning grass eating will make the best use of its stores. "The plan the Health cattle into cannibals, the disease has largely been brought Minister announced was to use the stockpile to enable one under control. Deaths from variant CJD have been falling million ‘essential workers' to take Tamiflu each day for a period of 6 weeks to prevent infection," he writes (see The Hendra virus caused panic in the horseracing industry pp.7–10). "This is a complete waste of a valuable drug. What in 1994, and bouts of the closely related Nipah virus have happens after 6 weeks, when the stockpile is exhausted and caused hundreds of deaths in Asia (see pp.20–21). However, the pandemic is still raging?" a vaccine is now being tested, and it looks like we may be able Athol Yates of the Australian Homeland Security Research to protect ourselves against this pair before they can do much Centre is not so damning, but he sees nine ways that the more damage. Similarly the use of effective public health Australian pandemic plan could fail (see pp.15–19). One issue measures brought an end to the SARS crisis of 2003, although that Yates doesn't mention is our heavy reliance on Tamiflu.
re-emergence is possible.
Relenza is Australian, and taxpayers invested almost This has happened because all diseases have weaknesses.
$250 million in its development. Yet our stockpile is mostly A disease can't afford to kill its hosts before they can infect Tamiflu, which, while based on Australian research, was a new host – which is why the ebola virus makes for good developed overseas.
horror movies but isn't likely to turn up in Sydney any time Tamiflu has been chosen because it comes in pills while soon. Of the 1500 people known to have been infected with Relenza is inhaled. However, more than patriotism suggests this terrible disease – which causes bleeding from every that we might want to even up the balance. Widespread use opening in the body – fatality has occurred in 80% of cases.
However, most have died too quickly to transmit the virus, and of Tamiflu will cause the same selection pressures that see only poor hygiene in impoverished hospitals has allowed the bacteria become resistant to antibiotics. Having a different number of deaths we've seen.
drug as a second line of defence may prove invaluable.
Which is why the disease that really gives experts sleep- The government has reasons for its choices. Maybe they're less nights is avian flu. There is a huge reservoir of birds out the right choices, but what is really worrying is how little there with the disease (some of which carry it without getting debate there has been on these topics. An avian outbreak sick), and we know how easily flu can be transmitted from could be the greatest disaster since World War II, yet there's one person to another.
hardly any discussion on how best to prepare for it.
JUNE 2006

Source: http://issues.control.com.au/issues2006/75editorial.pdf