A Post about Vaccines
Group A Streptococcus pyrogenes is the culprit behind a large slew of infections, a very mild but common infection caused by this bacterium is strep throat. I contracted this many times as a child and it is almost common to know someone who has had it at some point if not once a year. While most people would agree strep throat is not desirable this bacterium can cause much more severe and potentially deadly illnesses such as scarlet fever and other severe skin rashes(2).
Often strep can be treated relatively easily, but for the more severe illnesses caused by S. pyrogenes there is still a long way to go. The article this week is from the Indian Journal of Medical Microbiology and the researchers are trying to determine a vaccine for the many infections caused by S. pyrogenes. They are particularly focused on treating rheumatic fever/ rheumatic heart disease (RF/RHD). What is tricky about treating RF/RHD is that this is not even directly caused by S. pyrogenes, it is actually a condition that is formed as a result of the infection itself(1).
Designing a vaccine takes skill and patients and despite how much vaccines are in the news the process of creating them is often lost and seems almost simple. As genetics would dictate however, some bacterium are very complicated and finding the right sequence of genes that cause the virulence factors of those bacterium can be difficult. As the article mentions the public perceptions and cost are also very important aspects to consider, in the article it is mentioned that the there are a high number of people that do not get vaccinated due to fear of injection. A researchers job not only becomes what part of this bacteria can be targeted to affect the greatest amount of strains but what is the fewest amount of injections a person will need.
There is also the consideration of different regions having to have different versions of the vaccine. For example, one of the findings of the M protein "vaccines was that in industrialized regions 72% of M types were covered but only 24% in Pacific regions"(1). This is because there are over 200 M types that cause human infection, so finding something that targets all of them is also an obstacle in this specific vaccine.
Luckily, with the advent of faster and better genetic sequencing methods creating a vaccine has become easier. For the particular case of S.pyrogenes there are many virulence factors that can be the target of antibodies the major player however are M proteins. As discussed earlier their are a large amount of these suckers however the antibodies for M proteins give specific immunity to Group A streptococci.
Researchers who work with vaccine design have to take into account a huge amount of data and even if the vaccine gets approved and is available to the public there is still public opinion to get through. With the influence of better gene sequencing methods there will hopefully be many more treatment options and preventative measures for infections, illnesses and diseases that kill thousands.
1. Brahmadathan, N K. "Molecular Biology of Group a Streptococcus and Its Implications in Vaccine Strategies." Indian Journal of Medical Microbiology, vol. 35, no. 2, Apr. 2017, pp. 176-183.
2. Patterson MJ. Streptococcus. In: Baron S, editor. Medical Microbiology. 4th edition. Galveston (TX): University of Texas Medical Branch at Galveston; 1996. Chapter 13. Available from: https://www.ncbi.nlm.nih.gov/books/NBK7611/
Often strep can be treated relatively easily, but for the more severe illnesses caused by S. pyrogenes there is still a long way to go. The article this week is from the Indian Journal of Medical Microbiology and the researchers are trying to determine a vaccine for the many infections caused by S. pyrogenes. They are particularly focused on treating rheumatic fever/ rheumatic heart disease (RF/RHD). What is tricky about treating RF/RHD is that this is not even directly caused by S. pyrogenes, it is actually a condition that is formed as a result of the infection itself(1).
Designing a vaccine takes skill and patients and despite how much vaccines are in the news the process of creating them is often lost and seems almost simple. As genetics would dictate however, some bacterium are very complicated and finding the right sequence of genes that cause the virulence factors of those bacterium can be difficult. As the article mentions the public perceptions and cost are also very important aspects to consider, in the article it is mentioned that the there are a high number of people that do not get vaccinated due to fear of injection. A researchers job not only becomes what part of this bacteria can be targeted to affect the greatest amount of strains but what is the fewest amount of injections a person will need.
There is also the consideration of different regions having to have different versions of the vaccine. For example, one of the findings of the M protein "vaccines was that in industrialized regions 72% of M types were covered but only 24% in Pacific regions"(1). This is because there are over 200 M types that cause human infection, so finding something that targets all of them is also an obstacle in this specific vaccine.
Luckily, with the advent of faster and better genetic sequencing methods creating a vaccine has become easier. For the particular case of S.pyrogenes there are many virulence factors that can be the target of antibodies the major player however are M proteins. As discussed earlier their are a large amount of these suckers however the antibodies for M proteins give specific immunity to Group A streptococci.
Researchers who work with vaccine design have to take into account a huge amount of data and even if the vaccine gets approved and is available to the public there is still public opinion to get through. With the influence of better gene sequencing methods there will hopefully be many more treatment options and preventative measures for infections, illnesses and diseases that kill thousands.
1. Brahmadathan, N K. "Molecular Biology of Group a Streptococcus and Its Implications in Vaccine Strategies." Indian Journal of Medical Microbiology, vol. 35, no. 2, Apr. 2017, pp. 176-183.
2. Patterson MJ. Streptococcus. In: Baron S, editor. Medical Microbiology. 4th edition. Galveston (TX): University of Texas Medical Branch at Galveston; 1996. Chapter 13. Available from: https://www.ncbi.nlm.nih.gov/books/NBK7611/
Great time to post this considering the free flu shots now. It makes since that different areas would have different vaccines types I think just because the kinds of diseases or strains may vary depending on the place on earth. Then not even everyone gets them, as I have learned some do it because they are nervous about what goes into their body which makes since, but some do it because they do not feel they need it. Some just do not get the flu as easily as others. I forget the term but there is a description for when a majority of a group getting a vaccine also defends those who do not just because that flu or disease now has less chance to spread so this may be the case.
ReplyDeleteI found your post to be quite enjoyable. Microbiology is my favorite subject so I knew quite a bit about the causative agent and the many other diseases that it is responsible for. However, I was not aware of the progress being made in terms of vaccine production. Overall, great post and Lucio, the term is Herd Immunity.
ReplyDeleteGreat job on this post! I find the fact that something so small could wreck so much havoc on our bodies fascinating. Microbiology is definitely an interesting subject but it sucks that these bacteria can evolve so quickly that our medicine doesn't seem to catch up.
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