Merck's mumps vaccine is good. But not good enough.

It came out this week that two former employees are suing Merck (here's the document), the pharmaceutical company/giant, over what they say was a deliberate attempt to con the US government - and by extension many other countries - into buying a mumps vaccine in the form of their combination MMR-II vaccine that was not as effective as they had previously stated. 


As documented here this has been jumped on by a number of anti-vaccinationists but if you really look at the data from the "real world", you'll quickly see how all parties have really jumped the gun a bit on this issue and that clearly the vaccine is - and has been - working well. But it could be better.

Single mumps vaccine jab (versus MMR) in the UK - back again?

The "Children's Immunisation Centre" has recently announced that it plans to start administering the single mumps vaccine sometime in the 2nd quarter of this year in the UK. When I rang them up asked at the helpdesk, the very helpful receptionist told me they were scheduling vaccinations for July. Their website details:

"Currently Mumps single vaccine is not available due to Merck stopping the manufacture of it about 3 years ago. However we are working with our suppliers (who have an MHRA -Medicines and  Healthcare products Regulatory Agency - Wholesale license and who are regularly inspected) to source a Jeryl Lynn Strain (the safest strain) of Mumps vaccine." 

They continue,

"M-M-R single vaccines are manufactured by, France, India, and in some European countries and also China, Russia and in future the  UK. Our suppliers in the UK are working with UK manufacturers and are looking to produce the single mumps vaccine  for our patients."

The internet has picked up on this as well, here.

The ethics of vaccination

Vaccines are distributed across the world and we desperately need them if we are to successfully control some our most deadly infectious diseases. But they also require vast sums of money and expertise - on the part of academic institutions and private companies - to develop, manufacture and ultimately, dispatch worldwide. They thus have the power to save lives and rapidly divide opinion, with governments at odds with some individuals over the way that vaccination may or may not infringe on their rights.

Do we really need a new measles vaccine?

Measles, that deadly childhood infectious disease is almost a distant memory to most people nowadays, that is except for a few isolated outbreaks across the US and Europe. This is all because of a really amazing preventative therapy: the vaccine.

Vaccines are great. They are by far the most effective means that we have to control - and hopefully eradicate - infectious diseases from a range of species. Measles is one of these diseases that, over the last half a decade or so, we have backed into a corner across the world. Before the introduction of global immunisation the measles virus caused around 2.6 million deaths, most of which were children. To show just how great the vaccine is: 2008 saw only 164,000 deaths (see the WHO data here). A big number still but a 97% decrease in associated fatalities is pretty impressive, so why then - in an editorial piece in the esteemed journal Vaccine, are they calling for researchers to develop a new vaccine?

Viruses at the crossroads of infection

Last week I wrote about a recent paper showing that in some cases influenza viruses can escape from the lungs of an infected person; here, it makes it's way to the local lymph nodes by infecting your lung's sentinal immune cells, the dendritic cells. In this instance, this mechanism is probably being used by our own body's as a defence: by capturing influenza virus in the lung we can kick start our immune system by handing it directly to T and B cells within the lymph nodes. But it can also have deadly implication, especially considering that possibly every virus will have some run in with a dendritic cell during an infection.

**for a great discussion of what goes on inside lymph nodes during the induction of an immune response, see last weeks This Week in Virology**

Complicated diagram of the role of dendritic cells in the immune response. On the left, DC's grab antigen (for example a virus) and thus move into nearby lymph nodes. Here they present antigen to T cells ( or B cells). These cells leave the lymph nodes to hunt down their specific antigenic target (shown on the right here whether the T cells move into infected tissues. What DC's can also do is carry infectious viruses into the lymph nodes where they are free to replicate inside the dense population of T and B cells. http://www.biken.osaka-u.ac.jp/COE/eng/project/images/fig-hirata-jpg.jpg