Comments on: Improved ECF live vaccine

By: VRiitho

VRiitho — Wed, 13 May 2015 13:23:31 +0000

This is a great idea given that vaccination with live parasite followed by treatment (ITM) is, so far, the most promising means of vaccination albeit with some safety and technical challenges. Apart from virulence, another aspect of attenuation that can be considered is arresting parasite development at early infection stages. Significant progress has been made in the malaria vaccine field with a genetically attenuated (GAP) Plasmodium falciparum parasite with vaccine potential having been developed by Stephan Kappe and others at Seattle Biomed. Given the similarity of these two pathogens, their is room for collaboration and exchange of ideas. A common challenge for both ECF and Malaria live vaccine development is obtaining sufficient live sporozoites from ticks/mosquitoes: finding a way to culture sporozoites in vitro would be a giant leap.

By: Vish Nene

Vish Nene — Tue, 12 May 2015 11:14:02 +0000

I like the idea of genetic manipulation of T. parva and believe we need such an activity (and have discussed this with Roger Pelle) as it will help answer a number of critical questions on pathogen biology, which also relate to disease. However, I/we need to think about this some more as a means of developing an attenuated vaccine as you would then want to target more than virulence. Genome editing is now being used routinely for Plasmodium/malaria.

By: Lucilla Steinaa

Lucilla Steinaa — Tue, 12 May 2015 11:11:05 +0000

Hi there
This is a possibility and the idea has been around for a longer period of time (I think). One have to weigh the advantages and disadvantages. Advantages would be low virulence on its own and I guess the aim would be no need of co-administration of antibiotics which would make it cheaper. Disadvantages would be that it is alive, need of cold chain, it is a GMO, it would probably still be able to recombine with other strains BUT overall it would be an improvement of the current live vaccine. However, it would require a number of different modified strains just like the current live vaccine which is composed of three different strains. We also know that the current vaccine does not protect well against buffalo derived T.parva, so it could be considered how such buffalo-strains could be incorporated to give a broader protection. This could certainly be material for a proposal and I am aware that something similar has been proposed (not funded) before but I guess that should not discourage anyone.