Opinion not fact

This appears to be the conservative view of evidence

The following question was put to political parties in my organisation's federal election questionnaire: Does your party accept that peer-reviewed scientific evidence should be used as a primary source of information in decision-making? It deeply troubles me that the coalition responded that it was their belief that, and I quote, 'All government decisions should be considered and well informed, and where appropriate scientific evidence and opinion must be consulted.' Scientists Australia-wide and indeed the broader community are right to feel deeply uncomfortable with a position that places opinion on an equal footing with research and knowledge that has been gathered by some of Australia's most respected scientific authorities, such as the CSIRO. Independent and scientific advice must always be delivered to and heard by governments, not just when it is appropriate. Scientists are the first to recognise that other factors may influence decision-making, such as economic circumstances, but opinion shouldn't be one of those factors. We must remain a nation driven by knowledge, not stifled by a doubt.

Growing old; aging gracefully or falling into decrepitude?

This analysis looks at the commonly held ideas of an aging 'time bomb' and finds that it is all just a bit overblown;

Taking a deeper look at recent surveys conducted in the region on issues related to ageing, specifically health care costs, pension benefits and intergenerational solidarity, it can be stated that health care costs for the increasing ageing populations will be more affordable than we think, that older persons are healthier than ever before, that older persons in the region want to work beyond the retirement age in larger numbers than assumed, that intergenerational solidarity is hardly on the decline, and that older persons are contributing to their families and societies in more positive ways than ever.

The real deal - an update

Forrest has linked to the updated Diel paper on the predictive value of QFT, which reinforces the failure of TST;

QFT+ = 198 out of 954
TST+ = 604 out of 954 (+5mm lump
TST+ = 242 out of 954 (-10mm lump)

and for those that progressed to active (n = 19)

QFT+ = 19 (100%)
TST 5mm+ = 17 (89.5%)
TST 10mm+ = 10 (52.6%)

To put that into words

This study found a 2-year rate of progression to active TB of nearly 15% for those who were QFT-positive, compared with 2.3% for those who were TST-positive

Obviously a 5mm TST is closer to the mark than a 10mm lump however TST false positives are ~200% of QFT+ and false negatives were significant.

Two of the subjects who progressed to disease were QFT-positive, but TST negative, each with a 0-mm induration.

------

In conclusion, our results demonstrate the benefits of using the highly specific QFT assay in place of the TST in populations at risk and with a high pre-test probability of MTB infection. QFT yielded a higher positive predictive value, not only for determination of LTBI status, but, more importantly, for identifying those most likely to develop active TB disease in the near future. Moreover, whereas in clinical settings the usefulness of IGRAs fall short of that of a ‘rule-out’ test for active TB, given a diagnostic sensitivity of only 81% to 88% [2], in healthy subjects with intact immune function the sensitivity of the tests for detecting LTBI is likely much higher. This is supported by our finding that QFT had a 100% negative predictive value for progression to active TB in our study of a large body of close contacts with a high pre-test likelihood of infection.

Sanford gives the skin test the flick

Sanford Health (which serves the regions of Iowa, Minnesota, Nebraska, Oklahoma and both North and South Dakota and has +17,000 employees) is on the case

Sanford Health in Fargo announced Friday a doctor was diagnosed with an active case of T-B, and up to 100 people may have been exposed.

According to the North Dakota Department of Health, the focus is now on notifying those who may have been exposed.

Clinics will soon be set up in Fargo for testing. A speicla blood test will be given, which is different from the skin test that is typically done.

Clinics will also be set up for those in rural areas.

Testing will go through North Dakota Public Health Lab in Bismarck.

Projecting, not predicting

Forrest has put up a new spreadsheet, adjusted for actual amounts and margins. What is interesting is that if you use the sheet for the USA alone and vary the growth to 50% (plus other changes to the format) you get a very interesting dividend stream, from 3c ps in 2010 to around 20c ps by 2015.

The USA is the big market for Cellestis, they have been supportive of the science and then the product since the early days and, more importantly, they believe that to eradicate TB you must treat latent TB.

Plus they speak English.

The 50% growth rate is the rate that the Cellestis USA sales team believe is reasonable and doable - let them do it!

Changes to dividend legislation - Australia

Changes To Australian Law On The Payment Of Dividends - Jones Day

Article by Matthew Latham  and Eddie Marshbaum

Overview

On 28 June 2010 significant changes to the dividend payment regime under the Corporations Act 2001 (Cth) came into effect. The changes apply to dividends declared on or after 28 June 2010. Rather than being able to pay dividends out of profits, a company may now pay a dividend only if it has satisfied three requirements, which focus on a balance-sheet test and the protection of shareholders and creditors.

The global economy, in pictures

Source

The US will no longer be the engine driver of the global economy; investors should be less fixated on the ^DJI

Dont panic dont panic

from Peter Martin

Crisis? Hardly. Financial markets shrugged off talk of ''mayhem'' and ''turmoil'' to trade roughly as normal on Monday, in some cases a little better.

The Australian dollar closed higher than on Friday, more than regaining the one US cent it lost in thin overseas trading before domestic trade opened. At 89.2 US cents late yesterday it was buying more than at any point on election eve.

The sharemarket closed almost unchanged in defiance of a slump on Wall Street with mining shares gaining as Telstra lost value.

''It's a squall in an Australian thimble,'' said economic analyst Sean Keane, from the Asia-Pacific consultancy Triple T.

''While it is absolutely correct that markets dislike uncertainty they will quickly move past this. Whatever the form of the ultimate coalition it is unlikely to do anything significant to affect the overall positive story that is unfolding in Australia.''

A senior economist, Rachel Logie, said the election outcome should make no difference whatsoever to the projections. Even abandoning the mining tax would make little difference, as mining investment would be constrained in any event.

''Miners can't get labour, miners can't get machinery,'' she said. ''Employment in construction is already as high as it was before the crisis. Oil and gas and iron ore miners are in competition with each other for that labour. That's the big constraint, not whether or not there is a tax.''

BIS Shrapnel is predicting a series of interest rate rises, taking the Reserve Bank cash rate from 4.5 per cent to 6.5 per cent over the three years. It expects the standard variable mortgage rate to climb to 9.1 per cent.

Long-term bond rates edged up early on Monday but most of the increase was reversed as buyers returned during the day.

''There are legions of bond hunters around the world looking for that rare mixture of a strong government issuing at a high yield,'' Mr Keane said. ''Those who own Aussie bonds have been well paid to do so, and they know it's likely the currency will climb higher.''

Funds manager Christopher Joye, of Rismark International, said the injection of three independents into Australia's political decision-making should be a plus for foreign investors.

''We will likely see an emphasis on better governance and transparency as flagged by the independents.''

Defining the market

In comments Merrywise says

I think you need to redefine the definition of a market ;). There are only 38 people who have sold today so far..

Or one person selling 38 times...that's the rumour...they had to sell a significant amount..

The picture tells the story

The market isn't happy with the latest results; stuffed if I know why

Looking forwards

Forrest thinks that a 10c dividend for the next financial year is entirely reasonable, and I would agree. This time last year long suffering shareholders were still waiting for the CDC to publish their updated guidelines and still waiting for Japan to implement QFT-GIT.

The Japan release was delayed until January 2010 and the US CDC did not publish the guidelines until June 2010, one year later. Despite these setbacks sales increased by 34%, well within the forecast target.

For the first time ever Cellestis are not having to look forward to an approval to be granted or a guideline to be published before sales can be energetically pursued; the way forwards is clear.

FY 2010 - so who won the comp?

With Cellestis preliminary results out it's hard to pick the absolute winner in Forrest's comp;

• Revenue varied between $60M and $30M with the closest being onefineday,

• NPAT was between $18M and $8.27M with closest being tassie,

• Dividends ranged from 7c to 2.5c with the closest, on 3.5c being Wallace, macduffy and yours truly.

With solid sales reflecting a growing market share all shareholders are winners.

I expect that this could be the last time foreign exchange will have a negative impact.

TST reactivity found to be induced by BCG vaccination at birth

Source

Overall our results showed that recent BCG vaccination affected TST reactivity in young infants but by 20 months of age the BCG vaccine had much less effect on the TST response.

And the winner is...

It would appear that the back room boys of the ALP were the big losers, looking at AEC results for many the informal votes were significant;

Blaxland - swing 3.89%  informal swing 5.33%
Watson - swing 8.66%  informal swing 4.48%

Tony! Tony! get out of debt!

Australian Treasury on the stimulus

Source

Several features of the global financial crisis conspired to make discretionary fiscal policy a particularly appropriate policy response. The contractionary shock was severe and highly synchronised across countries, which generated economic conditions particularly suited to a global fiscal policy response. The events surrounding the collapse of Lehman Brothers in mid September 2008 provided an unequivocal signal that a big contractionary shock was coming, and gave policymakers time to design and implement fiscal and monetary responses, without waiting for confirmation from macroeconomic data that the downturn had arrived.

For Australia, the evidence suggests that, without the discretionary fiscal action, the economy would have contracted not only in the December quarter 2008 (which it did) but also in the March and June quarters 2009, and that unemployment would have risen significantly more than it is now projected to do.

Time is money

in Spain;

We compared the cost of the tuberculin skin test (TST) with the QuantiFERON-TB Gold (QFT-G) test when screening for latent tuberculosis in 134 healthcare workers in Spain. The QFT-G test cost euro42.5 per healthcare worker, while the TST cost euro39.5. The tests varied in cost structure; most (70%) TST costs were due to time demands on the participants, whereas the QFT-G was more expensive in terms of consumables (50% of the total cost). Accordingly, the results depend on the hourly wages of the participants and the time they must dedicate to the tests. In the Spanish healthcare system, the societal costs of QFT-G are comparable to those of the TST, although their cost structures are quite distinct.

To be sure

Over at a fertility forum posters were thrown into conniptions;

Hi folks hoping to have IVF at the ARGC soon, had immune test etc and the clinic now requires me to have the Quantiferon gold TB blood test. phoned my GP she knew nothing about it said it would cost thousants etc. is there anywhere in Northern Ireland/southern Ireland  I can get this done or is it easier to go over to london?

and

Have any of you that have travelled from N. Ireland or S. Ireland been able to get a Quantiferon gold TB test done at home. following immune results I need this before starting humeria. Asked my local GP about having it, she never heard of it and said it would cost over a thousand pounds. 

Is it easier just to travel over to London to have it done? Any suggestions welcome

Not all were as confused

Your gp has never heard of the test for TB?! Where did she train? Mars?! LOL! Hang on a bit hon, I'm sure someone will be along soon who can answer your question, failing that, have you tried googling blood labs in Ireland???

Good point, just google it

Dublin

Dublin

It's all good

Much excitement by the scientists who believe that they have identified the gene clusters that differentiate active TB from latent TB, and other inflammatory diseases.

Here we identify a whole-blood 393 transcript signature for active TB in intermediate and high-burden settings, correlating with radiological extent of disease and reverting to that of healthy controls after treatment. A subset of patients with latent TB had signatures similar to those in patients with active TB. We also identify a specific 86-transcript signature that discriminates active TB from other inflammatory and infectious diseases. 

The press release strode a familiar path

Scientists have moved a step closer to developing a blood test that one day will be able to predict which 10 per cent of people who carry the TB bacterium in a latent form will later go on to have the full blown disease...

Unfortunately this is where they take a wrong turn, by referring to the group who are positive to the somewhat inefficient Mantoux

Some persons may react to the TST even though they are not infected with M. tuberculosis

Not to worry, the group is still significant and this research does hold some promise as an adjunct to the Interferon Gamma Release Assay

Prior BCG (bacille Calmette-Guérin) vaccination does not cause a false-positive IGRA test result.

Here's mud in your eye

Rotorua Area Primary Health Services (RAPHS), are quite clear on the best way forward;

We recommend Quantiferon Gold testing in place of Mantoux for preemployment screening and where indicated, pre-travel. The use of Quantiferon Gold for these indications is now well established worldwide and is already utilised for these indications in several parts of New Zealand

Politics is no refuge for the weak kneed - Real Action from Real Men

V

When it comes to national broadband

Tony Abbott says he doesnt understand

so what's the game plan Tony?

Remember when...

..Barnaby Joyce said that Australia is in imminent danger of defaulting on its government debt?

Well it didnt work then and doesnt wash now.

A true sovereign is free from default, end of story.

Open letter on the stimulus

Source

Nice work for some

Ramsey County has just cut a deal with TB infected inmates, $6.5M in base payments and $2.6M to the lawyers.

(U.S. District Judge Richard) Kyle called the case "hard-fought" and told both sides they ought to feel good about the settlement.

Previously Ramsey county had approved $10.6M as the

maximum "logical amount" that the county expects to pay

Logically the expected to pay ~$90,000 per botched TB infection.

I expect that this case will set a precedent and that other counties would not want to a repetition of these events.

Better late than never

Statute reform is a slow business in New Jersey;

The Department proposes amendments to the employee tuberculosis screening rule that are consistent with the Department’s communicable disease standards reflecting best practices for management of tuberculosis at N.J.A.C. 8:57-5, including the addition of the interferon gamma release assay as an approved screening method, and establishment of requirements and procedures for repeat and follow-up screenings.

QFT labs in San Diego

It would appear that San Diego has moved on from arguing the toss about gold standards - they are more focussed on telling you where you can get your QuantiFERON;

Kicking ass

Ex ALP leader Mark Latham urges a vote for the donkey,

to place a ‘‘totally blank’’ ballot in the box 

We did that when you were last up for election, Mark

Straight from the bull's mouth

Elio D’Amato at Lincoln Indicators;

At the moment, a couple of stocks that D’Amato thinks are in this position are PanAust (PNA), a copper producer in Laos, and Cellestis (CST), which makes a tuberculosis diagnostic and treatment. “PanAust is a good business, and Cellestis is a stock that has been producing good results year after year, but the share price is 25 per cent lower than a year ago...the market will repay faith in those sorts of businesses.”

He says Cellestis has earnings per share treble what it was in December 2007, yet the share price is only up by about 50 per cent in comparison. “There’s a lot to like about stocks like that, where the earnings growth is quite attractive, but the price, although it’s rising, is not keeping pace with the earnings. When the market finally cottons on to the growth story of what some of these companies are about, they can be rewarded with a sharp run in the share price,” says D’Amato.

Source

Something for the doom and gloom merchants

From New York;

Which country's stock market has been the best performer in the world -- not just over the past year or decade, but over the last 110 years? 
 
It's Australia, which stands above all others in its combination of higher returns and lower volatility..

The Crisis Down Under

Source: Project Syndicate

2010-08-05

CANBERRA – The Great Recession of 2008 reached the farthest corners of the earth. Here in Australia, they refer to it as the GFC – the global financial crisis.

Kevin Rudd, who was prime minister when the crisis struck, put in place one of the best-designed Keynesian stimulus packages of any country in the world. He realized that it was important to act early, with money that would be spent quickly, but that there was a risk that the crisis would not be over soon. So the first part of the stimulus was cash grants, followed by investments, which would take longer to put into place.

Rudd’s stimulus worked: Australia had the shortest and shallowest of recessions of the advanced industrial countries. But, ironically, attention has focused on the fact that some of the investment money was not spent as well as it might have been, and on the fiscal deficit that the downturn and the government’s response created.

Of course, we should strive to ensure that money is spent as productively as possible, but humans, and human institutions, are fallible, and there are costs to ensuring that money is well spent. To put it in economics jargon, efficiency requires equating the marginal cost associated with allocation (both in acquiring information about the relative benefits of different projects and in monitoring investments) with the marginal benefits. In a nutshell: it is wasteful to spend too much money preventing waste.

While the focus for the moment is on public-sector waste, that waste pales in comparison to the waste of resources resulting from a malfunctioning private financial sector, which in America already amounts to trillions of dollars. Likewise, the waste from not fully utilizing society’s resources – the inevitable consequence of not having had such a quick and strong stimulus – exceeds that of the public sector by an order of magnitude.

For an American, there is a certain amusement in Australian worries about the deficit and debt: their deficit as a percentage of GDP is less than half that of the US; their gross national debt is less than a third.

Deficit fetishism never makes sense – the national debt is only one side of a country’s balance sheet. Cutting back on high-return investments (like education, infrastructure, and technology) just to reduce the deficit is truly foolish, but especially so in the case of a country like Australia, whose debt is so low. Indeed, if one is concerned with a country’s long-run debt, as one should be, such deficit fetishism is particularly silly, since the higher growth resulting from these public investments will generate more tax revenues.

There is another irony: some of the same Australians who have criticized the deficits have also criticized proposals to increase taxes on mines. Australia is lucky to have a rich endowment of natural resources, including iron ore. These resources are part of the country’s patrimony. They belong to all the people. Yet in all countries, mining companies try to get these resources for free – or for as little as possible.

Of course, mining companies need to get a fair return on their investments. But the iron-ore companies have gotten a windfall gain as iron-ore prices have soared (nearly doubling since 2007). The increased profits are not a result of their mining prowess, but of China’s huge demand for steel.

There is no reason that mining companies should reap this reward for themselves. They should share the bonanza of higher prices with Australia’s citizens, and an appropriately designed mining tax is one way of ensuring that outcome.

This money should be set aside in a special fund, to be used for investment. The country will inevitably become poorer as it depletes its natural resources, unless the value of its human and physical capital increases.

Another issue playing out down under is global warming. If not a climate-change denier, the previous Australian government led by John Howard joined President George W. Bush in being a climate-change free rider: others would have to take responsibility for ensuring the planet’s survival.

This was especially strange, given that Australia has been one of the big beneficiaries of the Montreal convention, which banned ozone-destroying gases. Holes in the ozone layer exposed Australians to cancer-causing radiation. The international community banded together, banned the substances, and the holes are now closing. Nevertheless, the Howard government, like the Bush administration, was willing to expose the entire planet to the risks of global warming, which threaten the very existence of many island states.

Rudd campaigned on a promise to reverse that stance, but the failure of the climate-change talks in Copenhagen last December, when President Barack Obama refused to make the kind of commitment on behalf of the United States that was required, left Rudd’s government in an awkward position. The failure of US leadership has global consequences.

Citizens should consider the legacy they leave to their children, part of which is the financial debts they will pass down. But another part of our legacy is environmental. It is two-faced to claim to care about the future and then fail to ensure that the country is adequately compensated for the depletion of its resources, or ignore the degradation of the environment.

It is even worse to leave our children without adequate infrastructure and the other public investments needed to be competitive in the twenty-first century.

Every country faces these issues. Sometimes, one can see them with greater clarity by observing how others are confronting them. How Australians vote in their coming election may be a harbinger of things to come. Let’s hope – for their sake and for the world’s – that they see through the rhetorical flourishes and personal foibles to the larger issues at stake.

Joseph E. Stiglitz is University Professor at Columbia University and a Nobel laureate in Economics. His latest book, Freefall: Free Markets and the Sinking of the Global Economy, is now available in French, German, Japanese, and Spanish.

Catch 22

Whilst WHO maintain that

a single dose of BCG be given to neonates or as soon as possible after birth in countries with a high prevalence of TB

there are those in countries "with a high prevalence of TB" who maintain that the limited efficacy of BCG vaccination is one of

four important obstacles to further progress in global TB control

The problem is that whilst HIV is prevalent there is

no definitive evidence exists to suggest that BCG will protect HIV-infected infants against TB

and in fact, the reverse can be observed

specific immunity induced by BCG is severely compromised in HIV-infected infants. Further, BCG disease is very common in these infants

Therefore WHO has recommended that BCG be given only once they are shown to be HIV uninfected.

Implementing this recommendation is problematic when follow-up for the HIV diagnosis cannot be guaranteed, as missed vaccination may precipitate an epidemic of severe TB in the approximately 95% of HIV-exposed infants who do not become infected.

QuantiFERON, a cause for celebration

An update on starflower's predicament (if you remember that the TST was positive and the T-Spot was "borderline");

Hey... finally some good news!!!!  FINALLY :)  I got the result from the second blood test today and it was negative.  No TB treatment for me.

Whoo hoo!!!

Thanks to everyone for your prayers and positive thoughts

Heather 

And the crowd went wild!

WoooHooo is right!! Im thrilled for you! Our prayers have got power behind them :)


HIP HIP HORRAH!!!!


I can't tell you just how happy I am to hear that WONDERFUL NEWS!!   That is absolutely TERRIFIC!!!   What a blessing!! 

THAT DESERVES SOME CELEBRATING HEATHER!!    Have a Coke on ME!!!!

Oooh... a banana split.  That will be my plan for tomorrow :P

Hooray for the ultra-positive thinking!!!!!!!!!!!

Hooray for HEATHER!!!!!!!!!!!!!    WE ALL REJOICE WITH YOU!!!!


I'm really, really proud of you sis, you plunged forward with your convictions as to what you knew that something just could not be right.  You bravely faced facts and swallowed your fears and dreads and faced the music, with the hope that entire time that you wouldn't have to do it!  You went after doctors who could investigate it properly and didn't accept just anybody's word on it who didn't have any capacity to judge the situation and you listened to those who are the authorities in this regardless of your own thoughts or feelings.   You went the entire way with it Heather, and as it panned out, it wasn't necessary to have to go through it afterall!!   Yet, you were committed to doing what you had to regardless of the price it was going to force you to pay!! 

I AM SO PROUD OF YOU!!!!!!!!!!!!!

Your husband needs to TAKE YOU OUT FOR A REALLY SPECIAL DINNER - JUST THE TWO OF YOU TO CELEBRATE THIS VICTORY PROPERLY!!!!!!   Save the Banana split for when you're with the kids cause they should celebrate it with you too!

YAHOOOOOOO!!!!!!!!!!

Amazing how QuantiFERON can generate such enthusiasm.

Putting things into perspective

Whilst we wait for Cellestis' results it's worthwhile taking a long look at the Australian biotech sector. Forrest has been playing with some numbers and in their Beyond borders Global biotechnology report 2010 Ernest & Young note that

The revenues of the Australian publicly traded biotech industry grew from US$3.48 billion in 2008 to US$3.72 billion in 2009 — a 7% increase, significantly lower than the 26% growth rate achieved in 2008. However, this number was skewed by fluctuations in the exchange rate and CSL’s performance. When measured in Australian dollars, the industry grew by a scorching 28%, beating the growth seen in 2008. After netting out the impact of CSL’s strong performance, the revenues of the rest of the industry actually declined by 9% in US dollars.

They also note that the number of publicly listed companies fell 11%, from 83 to 74.

It becomes obvious that the effects of foreign exchange fluctuations can mask growth trends which is why Cellestis' use of local currency to express sales is so helpful

Some things just don't add up

In addressing false-positive tuberculin skin tests caused by BCG vaccination and NTM Pai and Menzies reviewed the evidence and then said that the absolute

effect on TST of BCG received in infancy is minimal, especially > or =10 years after vaccination. BCG received after infancy produces more frequent, more persistent and larger TST reactions.

In "absolute" terms they found that,

• When BCG is given in infancy, false-positive TST results due to BCG occur in 6% of vaccinated subjects
• When BCG is given after infancy, false-positive TST results due to BCG occur in 40% of vaccinated subjects

The Greek Army found that BCG vaccinations contributed to a staggering 86.4% of TST false positives

We found a significant discordance between TST and QFT-GIT in BCG-vaccinated Greek army recruits consistent with previous studies showing that BCG received after infancy produces false-positive TST reactions.

And yet Pai still says "show me the data"

Stated failure

In discussions with Nauru's President Marcus Stephen the Leader of the Opposition, Tony Abbott, let slip

"Sometimes I think we need a guided democracy," Mr Abbott joked as they wrapped up discussions, noting that the media in some other countries were "much less disruptive than they are here".

Nauru has a history of receiving bad advice, and acting on it.

Net assets in the trust funds administered by the Nauru Phosphate Royalties Trust (NPRT) had been valued at A$1,300 million in 1991, but the combined impact of excessive consumption spending, poor investment advice, and mismanagement reduced the value to an estimated A$138 million in 2002. 

It would be to Nauru's advantage to not act on Mr Abbott's advice.

Pressed for time

In a statement by the University of East Anglia titled The BBC has apologised for an "incorrect" remark the BBC said

The first thing to say is that the sentence : "The facts are that the emails were stolen and they revealed that some researchers in the university's Climatic Research Unit had been distorting the debate about global warming to make the threat seem even more serious than they believed it to be" is incorrect. For that I apologise wholeheartedly on behalf of the Today Programme. ….. in mitigation I can only say that this was a live programme being put together under the pressure of events, and as you said when you came to see BBC News, we were dealing with a matter that hadn’t at that stage been fully investigated and which was the subject of widespread comment and conjecture.

The phrase "pressure of events" appears to only apply to BBC broadcasts; checking "the facts" took them more than 9 months

The message is universal

The University of North Carolina have made their position quite clear;

“The Student Health Services is offering  the Quantiferon TB Gold (Blood Test) to determine the presence of Tuberculosis .  This test has been recommended by Center for Disease Control (CDC) as being a more  accurate test for tuberculosis Screening.  IPPD skin test will no longer be used for routine tuberculosis screening at the Student Health Services .

Updated August 06, 2010 11:50AM”

Lack of a gold standard has not prevented the University from choosing the more accurate test.

Predictive values of QuantiFERON®-TB Gold testing in screening for tuberculosis disease in asylum seekers

Authors: Harstad, I.1; Winje, B.A.2; Heldal, E.2; Oftung, F.2; Jacobsen, G.W.1
Source: The International Journal of Tuberculosis and Lung Disease, Volume 14, Number 9, September 2010 , pp. 1209-1211(3)
Publisher: International Union Against Tuberculosis and Lung Disease

Link



Abstract:
Screening with chest X-ray and the Mantoux test (the tuberculin skin test [TST]) is compulsory for adult asylum seekers who arrive in Norway. In 2005-2006, we included 823 asylum seekers in a study of the QuantiFERON®-TB Gold test (QFT-G), and followed them for 23-32 months. Eight subjects with a positive and one with a negative QFT-G test were diagnosed with tuberculosis (TB). The positive (PPV) and negative predictive values (NPV) for TB were respectively 3.3% and 99.8%. The PPV was 2.3% and the NPV 99.1% for TST ≥ 15 mm, and the NPV was 99.5% for TST ≥ 6 mm in combination with a negative QFT-G.

A field trial evaluating the Quantiferon Gold tuberculosis tube test in an endemic population

American Journal of Infection Control 

Michael R. Spence MD, MPHa, David Sibert RNa, Lisa Fleischer MDb and Adam Birks MT(ASCP)c

a Department of Quality Management, Kalispell Regional Medical Center, Kalispell, Montana
b Primary Care Facility, Kalispell Regional Medical Center, Kalispell, Montana
c Department of Microbiology, Kalispell Regional Medical Center, Kalispell, MT

Kalispell, Montana.  Available online 29 July 2010.

The Quantiferon Gold tuberculosis tube test is a sensitive and specific way to diagnosis latent and active tuberculosis. The test is easy to administer and potentially can be used under field conditions and in a remote analytical laboratory. We screened an endemic population under field conditions and transferred our specimens via express mail to a distant site for analysis.

The global impact of BCG vaccination

In 1994 the WHO set out their policy on TB;

WHO continues to recommend that a single dose of BCG be given to neonates or as soon as possible after birth in countries with a high prevalence of TB

Countries with a low burden of TB may choose to limit BCG vaccination to neonates and infants of recognized high-risk groups for the disease or to skin-test negative older children. In some low-burden populations, BCG vaccination has been largely replaced by intensified case detection and supervised early treatment.

and as we can see from the picture below, just about everybody is using the BCG vaccine

From the above it would appear that only the US and parts of Europe have rejected BCG vaccination in favour of intensified case detection and supervised early treatment. Therefore one could assume that only these countries test for latent TB, which is supported by the WHO publication on global TB diagnostics;

Established market economies (EMEs) 
PPD skin testing
requests = 40.9M
units = 81.9M (assume 50% wastage of PPD units)

ROW/non-EMEs
PPD skin testing
requests = 8.6M
units = 17.3M (assume 50% wastage of PPD units)

From the above it would appear that testing for latent TB is largely confined to USA, Japan and parts of Europe whilst the traffic of migrants ensures that BCG vaccinated people will need to be tested for LTBI.

Updated CDC guideline bears fruit..

..or so it would seem. The CDC does say that

An IGRA is preferred for testing persons from groups that historically have low rates of returning to have TSTs read.

which is just commonsense really. It would appear that not wanting to be caught flatfooted the US military are updating their policies

3.I.(1) (U) FOR DEPLOYERS WITHOUT A CURRENT TB TEST OR DOCUMENTATION AS A PREVIOUS TB CONVERTER, SCREENING WILL BE CONDUCTED PREDEPLOYMENT. FOR RAPID DEPLOYMENTS (48 HOURS OR LESS), IGRA TESTING IS PREFERRED AS THERE IS NO NEED FOR PATIENT RECALL TO OBTAIN RESULTS WHILE TST TESTING REQUIRES THE PATIENT TO RETURN TO DETERMINE SIZE OF INDURATION WITHIN 48 TO 72 HOURS OF TEST ADMINISTRATION.

USPACOM refers to the United States Pacific Command

A Scandalous Incompetence..

When Lee Reichman read the 1998 Kendig report on deficiencies in skin test reading he hit the roof - and he doesn't appear to take too kindly to the "but there is no gold standard" argument - he calls it a case of scandalous incompetence..

..To ignore, downplay, or postpone consideration of the findings of Kendig and colleagues would be the height of irresponsibility.

QuantiFERON - test of choice in San Francisco

San Francisco TB Control have a new website and its very good, in fact very good.

Mantoux and mast cell disorders

Interesting chat on the mast cell disorder forum (mast cells contain histamine and heparine and form part of the immune system). Anyway, "starflower" works as a part time volunteer at her son's day care clinic and the manager

suddenly decided that we need to get in compliance with state regulations... NOW.  Like yesterday.  One of those regulations is that all workers (I'm considered a worker even though I don't get paid) must have an annual TB test.

Starflower had the test done and then watched it like a hawk

I put on a bit of hydrocortisone lotion and thankfully the itching stopped.  The lump is quite flat... let's hope it's not a positive test!

There's a little bit of swelling, but it's soft and not very big (especially now that I'm not scratching it). I'll let you know what the nurse says tomorrow.

Well... the overactive immune system strikes again!  The nurse took one look at my arm and said, "Oooh... that is not negative."

kateswmo tried to help

I reacted to a TB test once... however, it was NOT TB... I reacted to the dye/preservatives within the TB test solution itself.

Back to starflower

I went to my doctor this morning and he DID start talking antibiotics.  For some reason he didn't have my chest x-ray yet, but I told him my concerns and gave him Dr. Castells contact information.  I just got a call back from the nurse and here's the news: My chest x-ray is clear, but Dr. Castells thinks that I should go through the treatment for latent TB.  I'm going to meet with that infectious disease specialist on July 30th...

jillyg recounted her botched injection of PPD

In my case, I watched the nurse inject the shot, but she didn't give it SC, she hit me in the muscle.   So of course, I got lump that hung around a bit, and she said it was positive.  Having injected over 400 mice in the lab, I knew darn well what it was from, but I had to jump throughhoops to finally convince them I did not have TB.  I got a re-test with the Canadian vaccine by a very proficient nurse who knew how to inject... came back NEGATIVE as expected.  I had another one several years later... again, it was negative.

which riverwn2 confirmed

I think Jill is right. Hon, I've given that test 100s of times and I still find myself teaching new nurses how-to do it right. It is barely under the skin and it should create a bubble. if it wasnt or didnt, the nurse may have done it wrong. Giving it too deeply or moving the syringe can create a false positive. You said you itched it right? That alone could create an error--not to mention the mast cell reaction.

starflower then did some reading

I am going to ask the infectious disease specialist about a blood test (I've been reading the CDC's website).  I don't know if it's available in my town, but I'm willing to drive to the next major city to get one.  A three-hour drive is better than several months of medication!

and then

I had a pleasant conversation this morning with Dr. Tom, the infectious disease specialist.  The voice of sanity!  He sent me for a T-Spot blood test to make sure the skin test was really a positive and not just a reaction from my hypersensitive immune system

However it wasn't quite so easy

OMG... the never-ending saga...

I got a call from Dr. Tom's office this morning.  The t-spot test came back "borderline."  So... he's sending me for a different kind of blood test (QuantiFERON Gold) to get more information.

Interesting to see how all this pans out..

Get Quantiferon - update

Two new additions to the list of institutions in North America which have

agreed to provide QFT testing services to outside physicians and laboratories.

This brings the total up to 144, of which 2 are in Canada.

The additions are Dekalb County, Georgia and Finlay Clinical Laboratory, Miami.

Under reading those lumps

Not only is the TB skin test subject to failure due to the non return of the patient to have the reaction read, it is subject to failure by way of the measurement and interpretation of the skin reaction is entirely subjective, and prone to human error.

This is a known and quantifiable factor and there is no evidence that it has been properly addressed. In 1998 Kendig et al published a study into the accuracy of skin test readers

Mantoux tuberculin reaction measuring 15 mm induration was read individually by a group of 52 practicing pediatricians, 33 pediatric house officers, 10 pediatric academicians, 11 registered nurses, and one pediatric nurse practitioner.

....93% of those in the study (99/107 participants) would have identified our known converter as tuberculin negative.

For some the skin test remains the test of choice because IGRA have failed to provide "sufficient data" or "quality data" and there is "no gold test" for TB infection.

IGRA - Swiss Lung Association

31st Annual Congress of the European Society of Mycobacteriology

There is no doubt that the IGRAs are a very useful tool for the detection of tuberculosis infection. More time and studies are needed for defining the precise indication and limits of the available tests, remembering that we have used the imprecise tuberculin skin test for over 100 years and have taken number of sound decisions based on it, and the IGRA are far better than the tuberculin skin test. The art of medicine is somehow the art of taking correct decisions based on a unperfect test.

Jean-Pierre Zellweger
Swiss Lung Association, Berne, Switzerland

Link

It's a fact - science is dying

Australian researchers tried out this quick quiz, nothing too hard mind;

"We asked six basic questions in a survey of 1,500 people and only 3 per cent or 4 per cent of them got them all correct," she said.

"Unfortunately 30 per cent of Australians think reptiles or dinosaurs and humans were alive at the same time, for example, which is probably something I guess worries us.

Other worrying aspects to the survey

• 29% of Australians don’t think evolution is currently occurring, and
• about a quarter don’t think humans are influencing the evolution of other species – a worrying statistic given the impact that human activity is having on the environment.

How did we end up so ignorant?

Returning back to return rates

Consider this study into TST return rates for drug users where they were paid either $10, $5 or nothing to return. The results were

More than 90% of those who received a $10 incentive and approximately 85% of those who received a $5 incentive retumed on time, as opposed to nly 33% of those who received no monetary incentive.

So why not just pay them?

The problem is that the system of inducements is open to manipulation

A logistical concern associated with the use of incentives is that some individuals may attempt to enroll more than once in the study or that ineligible subjects may try to enroll...a substantial level of duplicate and unnecessary screening in an ongoing program would reduce the cost-effectiveness of providing monetary incentives to increase return rates.

OK, so why not just flick the entire TST policy and use Quantiferon, which has a 100% result rate and avoids all the unnecessary complications with inducements and compliance?

Maybe it's too obvious..

Tangled up in blue

By comparison with their US counterpart the updated Canadian IGRA guidelines make for uninspiring reading. Despite acknowledging the higher specificity of IGRA

...IGRAs have very high specificity (93% – 99%)

...where BCG is given, TST specificity is low and variable (~60%).

they did not specify which IGRA has the higher specificity and, more importantly, they continue to recommend the less specific TST.

The concluding remarks

Ongoing studies should resolve these issues within the next few years and inform evidence-based guidelines on how to implement IGRAs in clinical practice.

reads like a cop out - when will enough studies ever be enough?

Let's consider return rates; they acknowledge that where return rates are low eg "homeless person or IV drug users" IGRA may be more cost effective. However there exists plenty of evidence that return rates are low in most populations eg

in an urban primary care clinic....Five hundred seventy-three (40%) patients returned for a reading by a health care professional.

With a 60% failure rate

Alternative strategies that are more convenient for parents are needed to obtain accurate readings by health care professionals when skin testing is deemed necessary.