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Tag Archives: vaccine

Back from the Dead

Halloween seems like a good time to resurrect old blog posts that haven’t seen the sunlight for several years. Creeping out of the tomb is my first blog post about Genes, DNA, Memes, and GMO foods. Rather than post it here, I decided to post it over on my Medium site to see if it can catch some new eyes.

Take a look: Linked Memes

 
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Posted by on October 26, 2015 in Uncategorized

 

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An Ebola Question

Olytico-Question-Mark-1024x576I’ve had a question about Ebola posted on the StackExchange Biology page for some time without getting any answers. Basically, I was wondering about how antibody responses to Ebola can drive either sterilizing immunity (the goal) or actually improve the virus’s entry into host cells (a big problem). The idea that Ebola antibodies may be detrimental to the host was first raised by Baize et al, and my question is how this has impacted efforts to develop an effective vaccine. For background, I’ve written about this topic previously.

If anyone knows what the current thinking is in this area, please point them my way.

 
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Posted by on September 4, 2015 in Uncategorized

 

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Even Terry Bradshaw has a good handle on Shingles

Too bad Terry Bradshaw didn’t pop in for a visit at the Royal’s clubhouse, he seems to be pretty aware of the pain and disability associated with Chicken Pox and Shingles.

Kansas City is a lock for the postseason – that’s KC topping out at 100% probability:

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What’s one thing that could completely undermine the Royal’s season? How about getting blindsided by a completely vaccine-preventable illness* with a long incubation time that could lead to numerous infections?

Relief pitcher Kelvin Herrera, left, and outfielder Alex Rios, right

Relief pitcher Kelvin Herrera, left, and outfielder Alex Rios, right

Completely preventable? The vaccine is about as likely to prevent infection by varicella  as the Royals are likely to get in the playoffs

Data from CDC

Data from CDC

With an incubation time of 10-21 days, varicella infection may not show up for some time after exposure, meaning that any previously unimmunized players may still come down with the pox. Fortunately, vaccination may still be done and be effective in preventing illness up to 5 days after infection, so intervention may be successful. Cross your fingers Royals fans. We can only hope that the management for the Royals as well as other teams are now up to speed on having their players fully vaccinated.

Oh – and for those of us who have had Chicken Pox at some time in our lives, here’s Terry to talk to you about getting vaccinated to prevent Shingles…

 
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Posted by on September 2, 2015 in Uncategorized

 

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Autism’s False Prophets Questions – Part II

vaccines-save-livesA second installment in questions referring to Paul Offit’s book, Autism’s False Prophets. These questions mark the last of those we will cover for this book.

Autism’s False Prophets                                                                           Name:

Chapter 11 Questions

A Place for Autism

  1. What evidence is there for a genetic cause of autism?
  1. Other than genetics, what other things may cause autism?
  1. Who is the Autism Diva, and where did she come from?
  1. Who is Peter Hotez, and how did he get involved in the public conversation about autism?
  1. What does Peter Hotez think is the hardest part of being parent to an autistic child?
  1. What does Kathleen Seidel say is a problem about the way that doctors and scientists see the world?
  1. As always, at the end of a book like this, I like to ask for your feedback on whether you found this book important, what it might lack, and whether you think that I should keep using it in future classes.
 
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Posted by on May 3, 2015 in Uncategorized

 

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An ounce of prevention: A microbiology extra credit opportunity

Most flu shots are administered  I.M. (intra muscularly), therefore, at a 90 degree angle relative to the skin.

Most flu shots are administered I.M. (intra muscularly), therefore, at a 90 degree angle relative to the skin.

Bob and Sally go to get their annual Flu vaccine at the public clinic. Every year, the two go together and neither have contracted Influenza since they began five years ago.

This time, while he was getting his shot, he says to his nurse, “These shots are great. I haven’t been infected with the Flu for years, despite at least some of my co-workers getting sick every year.”

His nurse finishes his injection and then says, “Well, you might have gotten infected, but you’ve didn’t get sick.”

“What do you mean? Isn’t that the same thing?”

“Actually,” says the nurse, ” it’s not.”

Explain what the nurse means by ‘infection’ and ‘getting sick’ being different things. Include, in your explanation, why it is that a vaccine might not prevent organisms from getting into your body and even into your cells, but that they can still fail to make you ill. What cells and molecules are involved in protecting you in this way?

 
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Posted by on May 1, 2015 in Uncategorized

 

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HCV, briefly

Viral Hepatitis comes in a number of flavors, named HAV, HBV, HCV, HDV, and HEV (not to mention any subtypes). HCV, identified as recently as 1990, is a serious form of Hepatitis causing cirrhosis of the liver, chronic infection, and often hepatocellular cancer. Prior to 1990, the most common way to become infected was through transfusion with contaminated blood. However, after identifying the virus, tests became available to prevent this form of passage, leaving the primary mode of transmission being sharing of needles between IV drug users and sexual contact.
Unlike other viruses (HAV), few people ever clear HCV and, instead, become chronically ill. This may, in part, be due to the inability of the body to generate protective, neutralizing antibodies. Those antibodies that are produced are mostly usable only as markers of disease. Symptoms of disease include fatigue, nausea, vomiting, loss of appetite, abdominal pain, jaundice, dark urine, and clay colored feces. The CDC definition of a case is: (sorry this isn’t clearer)

acute-hcv-infection-cdc2012-case-definition.jpg

Serum alanine aminotransferase (ALT) levels greater than 400 IU/L indicate hepatocellular damage. This enzyme is normally found only in
liver cells, but is released into the blood when these cells are injured. Normal ALT should not exceed 60 IU/L, providing a fairly clear altmeasure of cell injury.This can be seen clearly below as serum levels of ALT spike with symptoms of disease and then return (however not down to normal, ‘healthy’ amounts) to lower levels following resolution of symptoms.

symptoms-acute-hepatitis-c-infection.jpg

There is no vaccine against HCV, so the best way to avoid it is to avoid contact with blood or other bodily fluids that may be contaminated.


Don’t forget to check out my comments on the novel ‘Rosemary’s Baby’ on my other blog. I highly recommend this book to anyone who enjoys thrillers / light horror (a la Stephen King).

 
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Posted by on April 12, 2015 in Uncategorized

 

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Science on Trial – Science in the Media

Amongst the many interesting topics that Paul Offit’s Autism’s False Prophets brings up are how science is perceived in the media, received by the public, and judged in the courtroom.

For reference, Offit brings up the fiasco of the 1990s lawsuits against the makers of silicone implants.

Kristin E. Schleiter writes an excellent paper about the history of silicone implants and the litigation that followed them in Silicone Breast Implant Litigation in the AMA Journal of Ethics.

Breast implants, she says, were first introduced in the 1960s. In 1976, the FDA was granted the power to regulate them as medical devices, but did not specifically do so until 1988. Prior to that, in 1984, Maria Stern won [the first case against an implant manufacturer totaling] “$211,000 in compensatory damages and $1.5 million in punitive damages from silicone breast implant manufacturer Dow Corning after claiming that her breast implants caused autoimmune disease.” This was the first, but not last case to bring implants to court. In the 1990s public opinion was against the makers of breast implants and thousands of suits were filed against their makers.

A natural progression

A natural progression

-Schleiter’s paper goes through a list of important individual and class action cases that I don’t feel the need to repeat here, however it is a fascinating read.

In the midst of these lawsuits, the attorney, “John O’Connor, relied on PR and sympathy to win [his case representing client, Pamela Johnson]. O’Connor hired a public relations firm that gave interviews to Phil Donahue and 60 Minutes, and the trial was broadcast in its entirety on Court TV. At trial, O’Connor set up a rebuttable presumption, asking the jury to hold MEC liable unless the company could prove that they knew their implants were safe at the time they marketed them. “

That is, it doesn’t matter whether the implants caused damage, but instead, whether the company, MEC, could prove them to be safe.

In the wake of litigation, studies began appearing showing the lack of any connection between breast implants and negative health outcomes.

Schleiter provides a list of papers reviewing the safety or danger linked to implants consolidated here:

  •  Plastic and Reconstructive Surgery published a study that found no increase in the incidence of breast cancer in women who had received breast implants
  • The New England Journal of Medicine soon followed with a study that concluded that breast implants did not substantially increase a woman’s risk for breast cancer
  • In 1994- New England Journal of Medicine published a study by Mayo Clinic epidemiologists that found no increased risk of connective tissue disease in women with silicone gel breast implants
  • In 1995, the Journal followed with yet another study—this one larger and more refined—that found no association between implants and connective tissue disorders.
  • In 1997, the American Academy of Neurology reviewed existing silicone gel breast implant studies and concluded that there was no link between the implants and neurological disorders
  • Also in 1997 Journal of the National Cancer Institute published a review of studies and concluded that breast implants did not cause breast cancer

However, billions of dollars had already been awarded or settled upon and Dow Corning was forced into Bankruptcy.

With respect to Offit’s book, the question arises, “How should science be settled in court?” It’s tempting to say that the cases should prompt investigations that statistically determine the culpability of, in this case, breast implant manufacturers. But that leads directly to one of the core problems that raised the specter of a MMR / Autism connection. Andrew Wakefield’s paper was intended to do just that – provide scientific evidence to help determine a case. In that case, the British government provided $30M to a law firm in order to fund their investigation. But that’s not proper either. To begin with an outcome in mind, i.e. “MMR shots cause autism” and then try to uncover evidence to support that idea is putting the cart in front of the horse. It’s OK to ask, “Does MMR vaccination cause autism?” and then look for the answer, but starting with the answer in mind – No.

For those in my Pathophysiology class, consider, as you read these next chapters, how these questions should be answered. If you were in the position to outline how cases involving questions of science / healthcare should be handled in court, how would you do it? Are these questions any different from the other questions that courts have to address?

 
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Posted by on February 15, 2015 in Uncategorized

 

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