All posts by Jo Madden

TB or not TB – that is the question?

"One world" Microbiology, Antimicrobial Resistance, History of Microbiology, The Science of Microbiology,

As usual my delving into family history has prompted a post … I’ve been researching my Great-great-Uncle who was killed in action at Somme, France whilst serving as a WW1 ANZAC and discovered that his father, my great-great-grandfather died from (and I shall quote from the Marlborough newspaper that it was printed in) … “that dread disease consumption“.

Now you may consider TB to be a third world, old-fashioned type of disease and to a degree you would be right however TB remains the second greatest killer globally (HIV/AIDS is number one) due to a single infectious agent.  In 2013, 9 million people fell ill with tuberculosis and 1.5 million died as a result – 480,000 of these cases were MDR-TB (multi drug resistant).  There is an upside to all this in that 37 million lives were saved due to effective diagnosis and treatment between 2000-2013 and the number falling ill to the disease each year is declining albeit slowly.  New Zealand statistics show 305 cases nationwide during 2014 and this number has been relatively stable over the past five years.

MDR-TB is defined as those strains that are resistant to at least Isoniazid and Rifampicin (the two most powerful and standard first line drugs for treatment of TB).   XDR-TB are strains that are extensively drug resistant and are defined as MDR-TB with additional resistance to any fluoroquinolone and at least one of the second line agents (Amikacin, Capreomycin or Kanamycin).  Of the 480,000 MDR-TB cases in 2013 about 9.0% of these were determined to be XDR-TB.  Within New Zealand the rate of resistance is much lower, on average only 1-2% of isolates each year showing this level of resistance.  In the past 10 years there have been 33 cases of MDR-TB in good ol’ NZ and all but two of these cases were born overseas where it has been assumed they contracted it – 29 of these 31 cases were born in an Asian country.  Only one case of XDR-TB has ever been identified in New Zealand, this was in 2010.  I think this is one time were our geographical isolation from a large part of the world is to our benefit.

Tuberculosis was a disease that the WHO considered dropping from their watchlist in the 1960’s/1970’s due to it’s decline however it made a huge resurgence in the 1990’s with the number of HIV/AIDS cases increasing and is certainly a disease which we cannot afford to ignore.

You can view a copy of the 2014 WHO global TB report here.

“It’s Not Rocket Science but it Saves Lives”

"One world" Microbiology, The Science of Microbiology, ,

We have a poster that says this above our handwashing basin in our laboratory and it’s true!

The United Nations states that “washing hands is the most cost-effective intervention for the worldwide control of disease” and yet studies have shown that up to 50% of people do NOT wash their hands after using the toilet.  Here are some interesting facts and figures based on basic hygiene:

* Between 2 and 10 million bacteria colonise our bodies between the fingertip and the elbow.  The fingertip bacterial load doubles after using the toilet.

* Touchscreen devices such as mobile phones, keyboards and tablets harbour 18 times more bacteria than toilet flush handles.  Not to mention the number of people that actually use their mobile phones while on the loo – YUCK!

* The bottoms of handbags are known for being covered in bacteria including faecal coliforms especially if they are placed on toilet floors whilst using public facilities –  a lot of these handbags are then placed or stored on kitchen worktops – hang your bag where possible.

* 80% of communicable diseases are transmitted by touch.  Touch referring to the touching of food as well as ones own mouth, eyes, ears etc. – not simply person to person contact.

* Critical hand washing times are before food preparation and before and after using the toilet.  Only 20% of people wash their hands before preparing food.

* Flushing the toilet with the lid up spreads a fine bacterial mist over an area of 6 square metres – see guys, it pays to always leave the seat down then it is easier to close the lid.

So it is very much “back to basics” with this topic but important to remember on a daily basis especially as the cold and flu season is just around the corner and washing hands has been shown to reduce the rate of sick days by more than 20% not to mention we are still in the thick of BBQ season and I am sure hand washing reduces the rates of those gastro organisms also.

Nitpicking

"One world" Microbiology, History of Microbiology, The Art of Microbiology, The Science of Microbiology, ,

I’ve been doing some reading lately, mainly on the subject of World War I and it naturally brings to mind topics for this website ….. this time “lice”.

Why are we not able to eradicate parasites such as lice?  Surely if the little blighters do not have a host to live off then they die therefore minus the hosts and we shouldn’t have issues of lice, yes?

I guess it is the age old problem of compliance … there is always a host somewhere who is not willing or able to get rid of them and therefore continues to spread them to those who spend many hours and much money to de-louse their children (mainly) from these wriggly little pests.  I am referring in general to head lice which seem to be a fact of life throughout most kids journey through primary school however with the very popular “selfie” causing a surge in cases in older age groups also.  It is the sort of nuisance that if everyone cared enough to treat and eradicate then we should be able to get rid of ……

The head louse ( Pediculus humanus capitis) is essentially a harmless pest.  It is a wingless insect which spends its entire life on the head of a host feeding off small amounts of blood.  They cannot fly or jump and do not transmit disease although they can be responsible for secondary infections of the skin due to scratching.  They are simply a nuisance and one that should be able to be eliminated from our society.

Body lice (Pediculus humanus corporis and sometimes Pediculus humanus humanus), common during the Great War, are far more dangerous due to their potential to transmit  diseases such as typhus and trench fever.  The two species are physically very similar, almost indistinguishable, but do not interbreed however they have been known to under laboratory conditions.  Again a parasitic pest that should be able to be eliminated with adequate hygiene practises.

If the world can eradicate smallpox (Variola virus – declared obsolete by the WHO in 1979) then why can we not do the same with our Pediculus friends?  Just as we needed the “buy in” of people to get vaccinated against smallpox we should be able to get their “buy in” to de-louse.