Some teachers are pricks, and then some

12 09 2010

A simple investigation experiment looking at the pH of blood at a Tasmanian high school has turned into a biohazard scare after teacher somehow thought sharing needles would be totally fine for adolescent boys. In some muddled form of defence the teacher did “attempt to sterilise the needle with methylated spirits between tests.” (Methylated spirits its not really suitable for sterilizing).

Pretty much any official is saying that this was a major balls up by the teacher, and I’m finding hard to believe that with all the red tape (in the for of occupational health and safety) present in Australian workplaces these days, that this investigation was ever approved. I have no problem with hands on experiments. In fact, I think these should be encouraged. On top of that, if we expect to have smart and scientifically literate graduates from high school, experiments involving potential biohazards should be allowed. However (or even because of that) it still very important to recognise that risks are involved and the appropriate precautions be taken.

Do read the comments on The Mercury article too.

There seems to be some sections of the world who are somehow thinking that the teacher has not done anything wrong, because there are no schoolboys in Tasmania with bloodborne infectious disease. Perhaps they could do well to investigate the Health and Ageing website which show that historically (prior to vaccinations) they have been one of the highest risk groups for Hepatitis (which is probably the largest worry in this instance, rather than HIV). Blood-borne transmission is probably the number one risk that health organisations try to minimize to prevent the spread of disease.

Taking the buzz out of life

28 07 2010

Nature has an interesting article exploring the ramifications of a world without mosquitoes.

Overall the benefits appear to outweigh the negatives – but they are still given their credence. Mosquitoes, and their larvae, may be physicaly miniscule, but they are big players in the scheme of things. Their removal would have effects on food chains containing birds and fish, plus wider ecological effects – such as plants losing pollinators and changes to deer migration, and also possibly cause over-population in already stretched human communities.

Image: mosquito by tanakawho (CC by A from Flickr)

Trends in internet influenza

20 06 2009

At the start of the month, Google announced it was expanding its search-engine-based epidemiology surveillance tool, Flu Trends, to process information originating from Australia and New Zealand (previously it was processing U.S. statistics and a beta Mexico version).

The tool is based on there being a correlation between the number of people typing in influenza-related keywords into Google and the actual number of cases of influenza in the country. Google claims it is supported by historical data. The concept does make sense: when you are your family are sick with flu-like symptoms, that would be the time you are more likely to search for information on possible causes – Thus people searching for “flu” could reflect the cases across the country.

But I was skeptical at how well it would work in a pandemic. Google’s data might hold up for its recorded history, but that does not extend back to 1968-9 – the last influenza pandemic. A pandemic not only involves the potential for an increased number of influenza cases and increased severity of those cases, it also means an increased amount of media coverage and public awareness. When I last looked at Google Trends and health searches, I saw a possible link between media coverage of Kylie Minogue and Australian searches for breast cancer. There is a good reason to suspect that the statistical relationship between search terms and disease cases will not hold up during pandemic conditions. This concern is not addressed appropriately in the Flu Trends FAQ.


Google Flu Trends Data, as of 20 June, 2009. Click for larger image. A - US 2008/09 search data c.f. historical B - Australia 2008/2009 data c.f. historical (2008/09 dark blue, historical light blue). C - Australia historical data (blue) compared with official epidemiological seasonal ILI (infleunza-like-illness) data (orange)

Google Flu Trends Data, as of 20 June, 2009. Click for larger image. A - US 2008/09 search data c.f. historical B - Australia 2008/2009 data c.f. historical (2008/09 dark blue, historical light blue). C - Australia historical search data (blue) compared with official historical epidemiological seasonal ILI (infleunza-like-illness) data (orange)

Looking at the U.S data, for this past season, it looks like it could be an accurate reflection. And if anything, rather than seeing a spike of search term activity this year, there was not much difference than previous years. In fact, the historic data contains several search spikes that do not exist in this years trends. All this information could either accurately reflect that the influenza pandemic thus far has been little more than out-of-season seasonal flu, or, just maybe, that the increased media activity and awareness have actually actively decreased usage of Google for health information.

Were people being directly channeled towards non-search websites, like Were they getting enough influenza information from other websites they frequent, like news websites? Was there enough offline influenza resources that people did not feel the need to Google to find out more? Or were people just overloaded and desensitized by the mass media hysteria?

I still prefer the Rhiza Labs case-mapping tool. It is much more informative and accurate.

Pandemic in perspective

20 06 2009

Fear of disease vs. death toll
see more Funny Graphs

Pilgrims responsible for plague spread

21 09 2008

World Youth Day pilgrims have been blamed for an atypical spike in exotic influenza cases in NSW. CathNews.

Not quite the disease spike I was expecting. Perhaps raging hormones were kept in check .

According the Sydney Telegraph: “Nurses report seeing high rates of of virulent infections among New South Wales hospital patients with ‘new and unusual strains of flu from exotic places’.”

Flu outbreaks amongst the pilgrims occurred more than once (old ABCVideo).

But NSW Health spokespeople note it is impossible to lay the blame firmly on pilgrim carriers or whether its part of normal flu cycles.

Anti-vaccinationists winning the war against healthy children

21 09 2008

Re-emergence of diseases like measles and mumps amongst Canadian communities (see Respectful Insolence) is starting to show what the totally unfounded (see The Stats Blog)  fear surrounding the MMR and other children’s vaccines has the propensity to cause.

I also had a link to similar outbreaks emerging in the UK. Outbreaks in other parts of the world are also likely to happen.

Part of reading this stories has helped me learn another horrible fact about the ramifications of less children being vaccinated. It does not just affect children who aren’t being vaccinated. Vaccination relies upon a concept called “herd immunity”.

We all have heard how vaccines aren’t 100% effective in the first place. This is an anti-vaccinationists selling point. Every time you are exposed to the contagion there is a chance of your vaccine failing. Think of it like brakes on your car, you can only be in so many “near-miss” situations before you bang something.

The idea of mass vaccination is to reduce the number of gambles. If every child is vaccinated, there is virtually no entry point for the contagion to enter your community. Every unvaccinated child is a bad driver on the road with no brakes. Not only are they relying on the brakes on your car to reduce danger to their children, they are an additional risk that your children need to avoid.

Some savvy parents are taking this into mind. Daycares that allow unvaccinated children (or do not have data on enrolment vaccines) are seeing health informed parents remove their children to other institutions that provide. The link I lost had a story of a mother who found out one of her children’s friends mothers had bought into the anti-vaccinist screed – and promptly stopped their children playing. A similar incident is found on MSNBC:

Karey Williams [47, Chicago] never thought a parenting decision would come between her and a good friend. The two had known one another for a decade, supported each other through infertility treatment and had their first babies around the same time. But when she told the friend that she had stopped vaccinating her daughter at age 1, the relationship abruptly ended. “She said, ‘Well then, your child can’t come into my house,’”

You might think this is harsh. But these are serious deadly diseases, no parent should be reprimanded for ensuring the health of their children. Lifelong complications (such as deafness) are very very common amongst victims of these diseases.

The positive impact of mass vaccination has a very clear and positive record. Science-Based Medicine has put up the stats for major vaccines. All of them have efficacy rates of over 80%, and save thousands of lives every year (if not more). And none of them have autism as a proven side effect. Science-Based Medicine’s author, Mark Crislip also points out that if GP/Big Pharma was really some sort of evil diabolical institution, they’d be joining the anti-vaccinists. More vaccines, means less disease. Less disease, means less business.

“I am an Infectious Disease doctor. I make a living from treating diagnosing and treating infections. I don’t make dime one if people do not get infected, so I am against any and all vaccines as they cut into my bottom line” – Mark Crislip, Science-Based Medicine weblog

Mandatory safety measures such as bicycle helmets, seat belts, standardised testing of car breaks are important for road safety. Shouldn’t similar safety measures be mandated for children’s health and safety.

Human parasite’s goody two shoes cousin helps coral

28 08 2008

Malaria is one of the most important infectious diseases under study today. It has been with us since early medical history, and still persists as a major global threat.

The disease is caused by a parasite – a multicellular microorganism. Not just a simple bacteria, the malaria plasmodium is a complex critter that still remains quite mysterious. It is very hard to work with in the laboratory: it doesn’t culture well and the risks involved are immense.

The discovery of a non-infectious relative (albeit, rather distant) by Australian researchers is exciting news for many.

Paydirt hasn’t quite been hit as far as medical research. However the fun isn’t just for medicos, but the evolutionary biologists as well.

Chromera velia is clearly related to Plasmodium parasites, but rather than being a blood-borne obligate parasite of mammals and insects that rarely sees light of day, it is a plankton-like photosynthesising obligate symbiont of corals.

These long-lost cousins are so very different, it could almost make the ghost script of the next Wil Farrell comedy (or not, besides its been done before).

Can they really be from the same origin?

The evidence is convincing.

For more information, take a read of a great interview (it says so in the title) with the scientists responsible for the discovery, as well as the University of Sydney press release.

Image: Copyright University of Sydney. Use only for non-commercial and educational purposes with attribution.