Naked Science Forum

Life Sciences => Cells, Microbes & Viruses => Topic started by: Stacey Rollings on 03/02/2009 01:30:02

Title: Why has smallpox been eradicated but not the measles?
Post by: Stacey Rollings on 03/02/2009 01:30:02

Stacey Rollings asked the Naked Scientists:
   
I really enjoy your shows (http://www.thenakedscientists.com/HTML/podcasts/).  

My question is, why has smallpox been eradicated but not the measles?

Thanks for the podcasts (http://www.thenakedscientists.com/HTML/podcasts/)!

What do you think?

Title: Why has smallpox been eradicated but not the measles?
Post by: Chemistry4me on 03/02/2009 01:49:06

Quote

Measles virus is a spherical single-stranded RNA virus belonging to the paramyxoviridae family. It is spread by airborne droplets causing rash, cough and fever which lasts for several days. Although there is no treatment, most infected individuals recover by themselves. However, complications due to pneumonia occur in 2–27% of cases causing 56–86% of all measles deaths. Less commonly, measles infection can cause serious neurological complications. Compared to smallpox, the measles virus is considerably more contagious, capable of causing large outbreaks even in populations with high vaccine coverage. Nevertheless, measles shares several biological characteristics with smallpox which favour eradication: humans are the only reservoir for the virus (i.e. animals are not infected); measles causes a visible illness; infection leads to life-long immunity; cases often occur at regular intervals enabling the targeting of interventions; measles virus has only one genetic serotype which is relatively stable over time; an effective vaccine is available and accurate laboratory identification is possible.

Quote

Global eradication of measles is more difficult than for smallpox, mostly due to the greater virulence of the virus, needing almost universal vaccine coverage. However, success in the Americas has shown that measles eradication is technically feasible using existing vaccines and vaccination programmes. Growing international support, to deliver these programmes means that measles, like smallpox, can very well become a curiosity of history.

http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=387835

Title: Why has smallpox been eradicated but not the measles?
Post by: lyner on 11/02/2009 12:34:11

I think it could be due to cost-benefit factors. Measles is just not serious for us to bother to irradicate it. There are a few individuals who are seriously damaged by measles but smallpox is much more devastating, so it was considered worthwhile spending all the money in dealing with it.

Motor cars cause many more deaths than measles - what do 'they' do about that? Fit airbags.

"It's the economy, stupid." - to quote Bill Clinton.