29 January 2009

Prevention v. treatment (1st Global Health Blog Carnival!)

Constant readers, about a dozen of us who are interested in global health are co-blogging today in a Global Health Blog Carnival. If you are on Twitter, search the hashtag #ghnews. If you're not, we will try to get them all linked somewhere. This was organized (to the degree that blogger organize, which as you can guess is like herding small felines) by reporter and blogger Christine Gorman, formerly of TIME Magazine.

Our theme for today is prevention v. treatment. Fortuitously, the New England Journal of Medicine today is publishing an editorial (for which they have posted the free full text) that reminds us of the full burden and cost of MRSA. Drs. Cesar A. Arias and Barbara E. Murray say:
Faced with this gloomy picture, 21st-century clinicians must turn to compounds developed decades ago and previously abandoned because of toxicity — or test everything they can think of and use whatever looks active. ...
It is more difficult than ever to eradicate infections caused by antibiotic-resistant "superbugs," and the problem is exacerbated by a dry pipeline for new antimicrobials with bactericidal activity against gram-negative bacteria and enterococci. A concerted effort on the part of academic researchers and their institutions, industry, and government is crucial if humans are to maintain the upper hand in this battle against bacteria — a fight with global consequences. (NEJM 360(5):439-443)
As we've discussed time and time again, MRSA is increasingly common worldwide and increasingly costly to treat. Moreover, what has been presented by some as the first line of prevention for hospital-acquired MRSA — active surveillance and testing programs, also called "search and destroy" — is deeply controversial.

So what's the next step? Well, in the past, when medicine has wanted to nullify an infectious disease threat, it did not rely only on surveillance or asepsis; it developed a vaccine. And there have been a few efforts to develop a MRSA vaccine, which are recapped in a new article in Infectious Disease Clinics of North America (yes, that's a journal):
The most extensively tested vaccine against S aureus, which is a capsular polysaccharide-based vaccine known as StaphVAX, showed promise in an initial phase 3 trial, but was found to be ineffective in a confirmatory trial, leading to its development being halted. Likewise, a human IgG preparation known as INH-A21 (Veronate) with elevated levels of antibodies to the staphylococcal surface adhesins ClfA and SdrG made it into phase 3 testing, where it failed to show a clinical benefit. ... Given the multiple and sometimes redundant virulence factors of S aureus that enable it to be such a crafty pathogen, if a vaccine is to prove effective, it will have to be multicomponent, incorporating several surface proteins, toxoids, and surface polysaccharides. (23 (1): 153-171)
Several longtime MRSA researchers, including Dr. Robert S. Daum of the University of Chicago, who wrote the first paper calling attention to community-associated MRSA in 1998, have called for a vaccine to be made a research priority.

Any thoughts, constant readers? In the public mind, right now, vaccines are at a low point: People are turning away from them, manufacturing problems have led to shortages, and pharma no longer finds vaccine manufacturing a lucrative business sector. If a MRSA vaccine were developed, would you take it yourself before surgery, or give one to your children?


Anonymous said...

I think that this might be one of those cases where prevention is going to be tricky.

I suppose part of the question hinges on whether you think hospital staff should take greater precautions, or whether patients should inoculate themselves. Where one is a medical intervention, the other is a norm change.

I certainly think either is preferable to treatment, but I don't know if it'd be worthwhile to administer a vaccine to all children. After all, staph is extremely common; we may be defeating MRSA but breeding a different superbug

Anonymous said...

I'm speechless. Almost.

A vaccination? Just how many vaccinations are we up to now? If we build up an antibody to MRSA will we develop an autoimmune rejection of the normal Staphylococcus strains in and on our body? Not to mention allergies from vaccinations. Will washing of hands be ignored?

We won't have to look at WHERE this resistance comes from or how our practices might have caused it?

Will we then have a vaccination against Streptococcus, Pseudomonas, Acinetobacter... Just how many vaccines will we need?

daedalus2u said...

Prevention will work better than treatment because these things can get bad very fast. You have to treat before there is time for a culture. Treat with the wrong thing and you have made it worse.

Prevention with anti-microbials isn't going to work because they will all evolve resistance.

The point about other Staph is very well taken. A lot of what keeps MRSA in check is other benign Staph bacteria that suppress them (or suppress their quorum sensing which is the same thing but which they can't evolve resistance to). Suppress those benign Staph with a vaccine and you may be worse off.

I think we need to rethink the whole “kill and sterilize everything” paradigm. Killing methods that resistance can’t evolve for, heat above 120 C, UV, alcohol, strong oxidizing agents are all going to continue to work. The chemical methods, triclosan, pine oil, phenolics, antibiotics all increase resistance by selecting for upregulated resistance mechanisms.

Unknown said...

I have just watched my significant other fight off an almost fatal case of MRSA pneumonia over the past 3 weeks. He was hospitalized for 17 days, in ICU for 11 days. This began as what seemed to be a routine sinus infection, but was really MRSA. His ENT was seen a couple of days after the head stuffiness started. He was put on Avelox and a blister pack of prednisone. Eight days later, he returned to the ENT who observed that the "sinus" infection was worse and prescribed Augmenton (sp?). Do I wish that he had had the opportunity to be vaccinated against MRSA? You're damn right I do and if such a vaccine existed, I'd be one of the first in line to get it too and my children would be standing right in front of me!

All of this balderdash about not giving your children routine vaccines is simply what comes out of a male cow's ass! I'm 52-years-old. When I was child, I was vaccinated for everything except chicken pox and it didn't hurt me one bit. I'm not autistic or any of the other developmental conditions that have been wrongly blamed on vaccinations.

Given the choice between myself or my children or my partner getting a vaccination and running the miniscule risk involved or having the potential to suffer such diseases as polio, diptheria, rubella, hepatitis, etc., I'd opt for the vaccine. Both of my sons were given all the "routine" vaccinations when they were babies and on through childhood and they suffered no developmental side effects from being vaccinated. To have even considered not getting my children vaccinated would have been a gross example of child abuse and neglect by a parent who is supposed to protect their children's health and best interest.

In the 1930's my father was stricken with polio as a teenager and thankfully lived. However, he did have to learn to walk again and had problems with his legs the remainder of his life. Do you think that if the polio vaccine had existed prior to his contracting polio that he would have wanted to take it? You bet! People back then who had watched loved ones die from polio, whooping cough, rubella, etc. were thrilled when a new vaccine against one of the deadly "plagues" was developed and made available to the public. And, plagues is an accurate description of what some of these diseases used to be before medical researchers developed vaccines to control them. Look some of these diseases up in your history books. An outbreak of one of these diseases would spread like wildfire through the population and thousands would die. Did parents in the 20's, 30's, 40's, 50's, 60's, and 70's want vaccines against these diseases? More than they wanted air to breath! They wanted to spare their children from these deadly diseases that they had witnessed or that their parents had witnessed and were helpless against.

Polio was a disease that had been virtually eliminated in the United States due to the polio vaccine developed by Dr. Salk. I remember lining up at my elementary school to get the polio vaccine during the early 1960's. As more and more immigrants come to the United States from countries that do not the same access to vaccines that we do, the United States is once again dealing with diseases such as polio. The doctors in the US had quit giving polio vaccinations because of its near eradication in the US. That decision has left millions of younger American children and young adults unprotected against the polio that has been imported into our country again.

Digital Arts Blog said...

mrsa is out of control - me and my 3 kids have been getting the infection over and over again despite cleaning everything in the house including ourselves w/bleach- give me the vaccine now!!!!!

Anonymous said...

My child has had MRSA 17 times in 13 months. I would do anything for a well researched vaccine. He was treated like Ryan White in school by staff members. There is little support or compassion in the community for MRSA victims. It is terrifying to face alone. What can we do to get funding allocated for more research & treatment?

Anonymous said...

What about keeping supplies of benign staph in storage and unexposed to antibiotics and inoculating patients who develop resistance with these organisms? I have watched my staph grow increasingly resistant and dangerous over the years, and only wish I had the staph I had started with to reinoculate myself and start over. Sure they would get resistant again, but it would take years, and you could theoretically keep repeating the process.