January 22, 2008

Plague

Plague is one of those diseases that most of us relegate to the history books. Great outbursts of plague have had a dramatic impact upon history. Athens in the Peloponesian war was heavily blasted by plague, medieval Europe suffered greatly from the disease as did 19th Century China. The disease is largely transmitted by fleas living on rodents- rats it is presumed in medieval Europe- and proceeds to infect human beings afterwards. Human to human transmission is possible but the key catalyst for an outbreak appears to be the presence of rodents in large enough quantities. Plague no longer severely threatens developed world countries and in the world at the moment there are only an estimated 1-5,000 cases per year over the last twenty years. Africa seems to be the main locus of plague cases with 90% of the cases in the last five years coming in Madagascar, Tanzania, Mozambique, Malawi, Uganda, and the Democratic Republic of the Congo (DRC). Plague outbreaks though can have a dramatic effect on a country- in India in 1994 an outbreak killed 50 people in the city of Surat, an event which led to a nationwide collapse of trade and tourism and the loss of an estimated 600 million dollars to the Indian economy. Hence a recent study in the Public Library of Science's Medicine Journal calls for more attention to be paid to the disease and to methods of treating it- and also to studies of whether the disease may be able to evolve into new forms in order to further threaten humanity.

I don't consider myself as having the medical expertise to comment upon the development of plague as a disease- no doubt others are in a better position. But one thing that is interesting does arise I think from this analysis and that is that economic development tends to present new opportunities for the aspiring virus and to erradicate disease. It presents new opportunities because increased trade leads to increased human contact and hence the risk of infection. Nigerian truck drivers spread aids to South African prostitutes. It tends to erradicate diseases because it presents us with options to control and contain the disease in locations or by advancing cleanliness and healthiness amongst the general population. Successful public education campaigns in the US and Europe helped eliminate Aids through encouraging condom use for example. Furthermore a well developed health service can lead to diseases being spotted earlier and therefore dealt with more quickly. I wonder and this is just a thought that others can comment on, whether there are particular states of society in which epidemics are more likely to hit than not. Obviously in the events after the breakdown of sophisticated societies during wars- like say the influenza epidemic of 1918- we should expect massive dislocation and possible medical disasters. But are there other moments- for instance at the birth of capitalism where the structures of trade have evolved faster than the wider society- when we should look for epidemics. I wonder if anyone has plotted this data- if they have it would be fascinating.

The studies on plague are interesting and worth thinking about- the disease may not be a historical footnote.

I should say I've written a further post about plague and climate change over at the Liberal Conspiracy.

2 comments:

jmb said...

This post sent me searching. I especially wanted to see what drugs were used. 10-15 cases every year in the US with 2006 a peak year. I found it interesting that more than 50% of cases are in the under 20 yrs group.

Bretwalda Edwin-Higham said...

A plague upon the plague.