Neglected tropical diseases(diseases of poverty)

Warwick GrantGenetics Department

What are neglected tropical diseases?

• These are primarily diseases of poverty• They either do not occur at all in developed

countries or are rare and of minor importance• But they affect tens to hundreds of millions in

developing countries, especially in sub-Saharan Africa where the poorest of the poor are concentrated

Parasitic diseases are very common

• more that two thirds of the world population carry one more more species of parasite

• the most common are gastrointestinal helminths... or worms in plain English

• roundworms such as Ascaris, hookworms and Trichuris and flat worms such as Schistosoma.

• they rarely kill outright but they cause great morbidity (morbidity vs. mortality... who knows the difference?)

What are the diseases?

• They are listed at:http://apps.who.int/tdr/svc/diseases• This is the website of the branch of the World

Health Organisation (WHO) that has special responsibility for these diseases... Tropical Disease Research or TDR

• There are other links to more Non-Governmental Organisations, or NGO’s: just Google “neglected tropical diseases”

River blindness, or onchocerciasis

• spread by blackflies... called river blindness because the flies must be near a river to breed

• symptoms are slow to develop but the infection is essentially incurable

• the symptoms are caused by the baby worms in the skin....

Where?

The life cycle

• http://apps.who.int/tdr/resources/animations/onchocerciasis-life-cycle.swf

Blindness

• estimates vary, but there are probably around 400,000 people who are blind or sight impaired as a result of infection

• there are possible 15 million total infections

• and an “at risk” population in the hundreds of millions

• no-one dies as a direct result of onchocerciasis but the infection may shorten life expectancy by 15+ years

Severe dermatitis

DALYS

• the WHO love their acronyms and this is a good one

• Daily Adjusted Life YearS• this is a measure of how much quality of life is

lost as well as quantity of life• for most of the neglected diseases of poverty,

the DALYS are the important measure

Lifelong infection, suffering and disability

• onchocerciasis causes:– blindness in severe cases– disfigurement of the skin... thickening, scarring,

depigmentation– intense itchiness, leading to scratching lesions and

secondary infections– disfiguring nodules where the adult worms live– immunological impairment, and disfigurement of

the axial and inguinal lymph glands – shortening of life expectancy

So what?

• The TDR (remember that is the branch of the World Health Organisation with special responsibility for these diseases)

• The TDR has a total budget of $70 million, for ALL of its activities

• Individual developed countries spend much, much more than this on diseases that cause a tiny fraction of the suffering

In Australia

• there is some funding (<$10M) for malaria research, largely because it is a “local” problem

• there is a tiny amount (<$1M) for research on one or two “worm” diseases, but only those that occur close to Australia (eg. in Papua, or in S.E. Asia where tourists go)

• there is nothing spent on oncho, or many other similarly serious diseases of poverty

The question?

• in philosophy, there is a school of thought that has been around for a long time called “utilitarianism”

• utilitarians are do-gooders who think we should try to do things that maximise the good in the society... the ethically right thing to do is the thing that brings most benefit to most people

• this usually means spending what resources are available on measures that help most people

What should we do?

• the Australian National Health and Medical Research Council has as one of their most important funding criteria that research must be focused on Australian health issues

• this all but rules out funding for the most important diseases in the world unless you can find an Australian angle

• most other developed countries are the same• and the tiny budgets of our government aid agencies

rarely fund disease research. • Should they?

Want to know more?

• dare I suggest:http://en.wikipedia.org/wiki/Onchocerciasis• but more seriously:http://www.cdc.gov/parasites/onchocerciasis/• and http://apps.who.int/tdr/svc/diseases/helminths• or just Google “onchocerciasis”

The Life You Can Save

http://www.thelifeyoucansave.com/

• information about the poorest of the poor, and what you can do about it....

• founded by a Melbourne philosopher (Peter Singer)... read the book with the same title.

• but back to the diseases...

How can you contact me?

• I am in the Genetics Department• My office is room 201, in Biological Sciences 1

(on the other side of the building site)• my email is w.grant@latrobe.edu.au• your best bet is to email me first to make a

time and then come and seem me• I am not here this Wed-Fri, or Tues-Wed of

next week.