Field of Science

Mumps outbreaks - why here, why now? and how can we stop it?

Mumps is an acute viral disease of humans and really only humans. It is spread through the respiratory tract (probably droplets and aerosols) where the virus most likely infects the cells lining the epithelium - we don't really know this for certain. From here it spreads throughout the body, infecting organs and tissues such as the salivary glands, testes and ovaries, pancreas, and perhaps most worryingly, your central nervous system. In fact, in the pre-vaccine era, mumps was the biggest cause of aseptic meningitis across the developed world; it can also cause the more severe encephalitis.

Lucky we've got a vaccine, right?

What's in a cough? Viruses. Lots of viruses.

A cough - Tang et al 2008
Respiratory pathogens are pro's when it comes to person-person transmission; easy in and easy out. Viral replication - and also I guess bacterial - followed by the subsequent immune response, induces a range of behaviors in the host which results in the expulsion of doses of infectious particles. These include your runny nose, coughs and sneezes -  you've all experienced them. Although even talking and breathing may also be spreading virus.

But, how exactly does the virus cause this? Which mechanism is potentially the most potent transmitter of virus? How many particles can be found in your average cough? And, how do these behaviors physically transfer infection? Perhaps most important - what can we do to stop it?

Did dinosaurs get measles?

 I know what you're thinking: of course they did - what organism out there isn't parasitized by viruses and their ilk? But where's the evidence? In science you can't just pluck ideas out of the air like this - no matter how obvious they are - and say they are true; maybe dinosaurs had a fantastic immune system and were able to thwart any potential viral invaders. What I'm saying is that we just don't know, but a paper published last month in Current Biology suggests otherwise: documenting the discovery that some dinosaur (see above) fossils bare lesions in their bones that are suggestive of viral infection.

Why don't we have a #dengue vaccine yet?

This is taken from a recent special issue of the journal Vaccine from September covering the "state-of-the-art" of dengue virus vaccine research. 

The process of generating - and testing -  a dengue vaccine captures the entire field of vaccinology and highlights it's promises and pit-falls and can be used as a model when thinking of any number of potential vaccine initiatives.

See below for my take and summary of this issue:

What can flies tell us about #virusevolution?

Some of the fly species used in this study (thanks to Ben Longdon).
 What influences whether a parasite - for example a virus - will infect a new host and jump species? Is it more to do with the virus, or the host? Maybe something entirely different, like whether the two hosts will ever meet. Investigating these factors may allow us to predict how viruses will behave in their natural environment and aid us in determining the likelihood of transmission and spread into - and throughout - a new species, like us, humans. Imagine if we had had this knowledge earlier, we may have been able to prevent such epidemics HIV, SARS or the recurring ebola outbreaks. 

 Well, this is exactly what one group - joint between Edinburgh and Cambridge Universities in the UK - are doing. Get the PLoS Pathogens paper here. Using perhaps the only experimentally amenable model system for animals - which consisted of flies and their viruses - they recently provide evidence that the likelihood of a virus replicating within a new host has a lot to do with how genetically related it is to the original host species. And, surprisingly, in some cases it has not much at all to with it - further compounding the complexities of virus emergence. But how did they do it?

#vaccines - can you predict how well they'll work?

Vaccines are great aren't they -  they offer us probably the most cost-effective means of reducing death and suffering on a worldwide scale that extends to both humans and other animals. The problem is that it's never been as easy as just dreaming up a vaccine for the latest virus to afflict us. Effective vaccines are extremely difficult to produce, even for the most well-researched pathogens and, even when you do develop one, plow billions into it's generation and testing, and get it successfully through all the necessary clinical trials it still might not work so perfectly.