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Epidemiology

The Deadly Toxin You May Not Have Heard About

By June 10, 2015 1 Comment
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In Spain a little boy is being kept alive by machines and eight other children have been hospitalized after being infected with a deadly toxin. This toxin can cause the nose of an infected individual to drip blood and pus-filled infection, the roof of their mouth to bleed and turn green and black, can obstruct their airways, and can cause patches of skin to become scaly and leather-like.

The toxin invades the body’s mucus membranes, enters the blood stream, and multiplies rapidly. Most alarming is that the first symptoms this toxin in the body are similar to that of a cold, until the inside of the victim’s mouth turns gray and scaly, by which point the toxin has likely already entered the bloodstream and attacked the other mucus membranes in the body, and the patient has likely already infected other people.

Twenty percent of infected patients under the age of five will die and 5-10% of patients over the age of five will die. That mortality rate has remained unchanged for 50 years, despite medical advances.

This toxin is caused by a naturally occurring bacteria of the same name called Corynebacterium diphtheriae, better known as diphtheria.

Diphtheria is one of those diseases we think about in the same way we think about cholera, typhoid, and consumption (TB). We think of it as a disease that people used to die from on The Oregon Trail, but that it’s not actually a thing anymore. Except that it is.

In the 1930s, diphtheria killed between 13,000 and 15,000 individuals annually in the United States. A diphtheria vaccine was developed in the 1920s, and became widely available in the ‘40s and ‘50s. The disease’s prevalence rate dropped off to a statistical zero by the 1980s.   Most people are vaccinated against diphtheria in childhood as a part of the DTaP vaccine, which protects against diphtheria, tetanus and pertussis (whooping cough). People older than the age of 11 need a Tdap booster shot every seven to nine years. The differences between the DTaP and Tdap vaccines are the antigen concentrations in each shot.

Diphtheria InfocardDiphtheria is in the news again due to a cluster of cases in Spain; in the Girona province of Catalonia, Spain (very close to the border of France), the index case (“patient zero”) is an unvaccinated little boy. Heartbreakingly, as of the writing this post the boy is in critical condition on life support, and his parents have expressed that they “feel terrible guilt” over not vaccinating their son and feel hoodwinked by the antivaccine community. Several months ago Tara Hills, a mother of seven, wrote on our blog about the guilt she felt after not vaccinating her children and their subsequent battle with whooping cough.

While the index patient in Spain was not vaccinated, initial reports of the subsequent eight infections indicate that the other patients were vaccinated. The reports, however, don’t indicate the age of the new patients (diphtheria is particularly virulent in those under age five) or if the eight had completed the World Health Organization’s full vaccination schedule. Additionally, those who have been vaccinated against diphtheria tend to develop a milder form of the disease as their bodies already have some of the antibodies needed to fight the bacteria and the toxin.

Treating diphtheria is complicated, many impacting factors including the age of the individual, their vaccination status, when in the disease’s progress they sought medical treatment, and how the bacteria entered the body can all vary the severity of the illness. Prevention is the first line of defense (get your shots, people!) but once infected, antitoxins, antibiotics and supportive care are the standard treatment. Complicating matters even further is that the diphtheria antitoxin is not a standard drug that hospitals keep on hand. In fact it’s only available through the CDC directly for us here in the US. The antitoxin also won’t neutralize existing pockets in the mucus membranes, it will only prevents the progression of the disease by neutralizing the toxin that’s circulating in the bloodstream. This is why the death rate from diphtheria remains so high.

As Rene Najera pointed out on Monday, many diseases are just a plane ride away. This disease could even easily spread to areas of southern France given its proximity to the border and the nature of cross-European transit, which is largely train and short-flight based. Even if you don’t plan to travel to Spain any time soon, now may be a good idea to check in with your doctor and make sure you and your family are up to date on your Tdap and DTaP shots. Heck, most health departments give them away for free (FREE!).

Editor’s note: Since the publication of this post, the little boy has since passed away. You can read more here.

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Categories: Infectious Disease + Vaccines, Policy, Politics, + Pop Health

Is It Time to Freak Out About MERS?

By June 8, 2015 3 Comments
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Middle Eastern Respiratory Syndrome virus (MERS) is a nasty infection and one you definitely don’t want to get. A recent outbreak of Middle Eastern Respiratory Syndrome virus (MERS) in Korea has a lot of people on edge, and for good reason. But what are the chances that you, sitting at home in the United States and other countries where MERS is not active, will get MERS? What are the chances that it will spread like wildfire and make many people sick and kill even more? And is it really that deadly? Let’s take these questions one by one and separate fact from worry.

According to the Centers for Disease Control and Prevention (CDC), the signs and symptoms of MERS are fever, cough, and shortness of breath. Those symptoms sound similar to just about any upper respiratory tract infection, but complications from MERS include kidney failure and severe pneumonia. Partly due to these complications, between 30% and 40% of patients with MERS cases have died, which is a very high mortality rate. Currently there isn’t a specific treatment for MERS, much like a cold or a stomach bug, treatment is supportive (fluids, fever reducers, pain killers etc…). The high mortality rate is why public health agencies across the world are on high alert.

Good for us (bad for MERS) unlike the flu or the measles, it turns out MERS isn’t easy to catch.

The MERS virus is a variant of the corona virus, a virus that has many different strains and causes different kinds of respiratory and gastrointestinal diseases. You’ll sometimes see “MERS” written as “MERS-CoV,” with “CoV” meaning “coronavirus.” Because the MERS strain of coronavirus is relatively new to humans, scientists are still working on fully understanding how it is transmitted.

One thing is for sure, close contact between people leads to transmission. Close contact can include healthcare providers caring for people with MERS and not using appropriate personal protective equipment or infectious disease precautions. Some of these providers not using those precautions have been infected. Also, people hospitalized with MERS patients have been infected, suggesting that the virus is spread via aerosols (e.g. sneezes and coughs) or is airborne (e.g. through breathing the same air).

MERS-CoV Infographic copyI mentioned before that MERS has a mortality rate between 30% and 40% and the high hospital transmission rate may be over-inflating the virus’ actual mortality rate. People who are already in the hospital for another illness or condition and contract MERS are likely to have more complications and worse outcomes (and a higher mortality rate).

Because MERS is so new (and until now has been relatively contained) disease surveillance systems have been only picking up cases that are hospitalized. It will likely take a while before systems are in place to detect sub-clinical cases (i.e. cases who don’t become sick enough to seek hospital care).

With that said, you may remember the H1N1 pandemic several years ago. In the US alone, thousands of people became so sick they sought care from their doctors and hospitals. We aren’t seeing this with MERS, which tells us that MERS is either a mild virus in those who are otherwise healthy or isn’t easily transmitted at the community level.

According to the Korean Ministry of Health, the first person identified in the current outbreak (what we call in public health the index case) was reported as having traveled recently to the Middle East. Seven days after his arrival, the index case sought care at different healthcare facilities in Korea, likely spreading the virus in those settings.

Taking all of this into consideration, it is very possible that MERS could spread to other parts of the world past Korea, in fact, there have already been cases in the United States. These cases in the US were unconnected and over 500 people were potentially exposed, but no one contracted the virus outside of the index cases.

We live in a world where a jet can depart the Middle East and be in any part of the world in a matter of hours. Combine that with the incubation time (time for symptoms to develop from the initial exposure) that MERS is displaying of about 2 to 14 days, and you could have plenty of cases popping up all over the globe.

So what is keeping that from happening?

First, it seems that exposure to camels or camel products (like milk) were the primary source of MERS infections in the Middle East. Second, modern healthcare facilities have strict infection control protocols that may be keeping infections from occurring within them. Third, as I mentioned above, the person-to-person transmission in the community – outside of healthcare facilities – seems to be limited.

In the United States, between 3,000 and 49,000 people die from influenza each year. Half a million of us die from smoking-related diseases like lung cancer, high blood pressure, and heart disease. Another half a million will die from heart disease associated with poor diet and lack of physical activity. And over 30,000 will die from traffic-related accidents. At this time and in the United States, MERS is on our public health radar, but in your day-to-day life it should be your least concern.

The best things you can do for your health (and others) are to wash your hands, eat a balanced diet, wash your hands, get plenty of exercise and plenty of rest, wash your hands, and follow your healthcare providers advice at all times, buckle-up in the car, and wash your hands. Also, don’t forget to wash your hands.

Edited by Leslie Waghorn

 

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Categories: Infectious Disease + Vaccines, Policy, Politics, + Pop Health

The Measles Drives Immunization Rates Up, but Whooping Cough Doesn’t Have the Same Effect in Washington State

By April 2, 2015 1 Comment
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On March 31, a prisoner escaped from a hospital about two miles from our house. He fired off a shot at police while he made his escape, and carjacked two individuals causing one car crash. The words, “armed and dangerous” and “area lock down” are not words that generally make the public feel safe, even after evidence suggested the prisoner had moved out of our immediate area.

It was this threat that made me realize how generally lax I am about safety in my own home. I had to confirm that the doors and windows were locked and as usual, I would have been lucky to find my phone to call 911 if I needed to. Theft and dangerous offenders aren’t something I worry about in our area because the crime rate is so low. It took an emergency for me to realize, “it might be a good idea if I knew how to lock our windows.”

Humans are terrible at judging risk. We’re categorically awful at it, and we don’t tend to act on slow-moving risks until the crisis is upon us. Reactively, rather than proactively. It looks like the same pattern is playing out in Washington State, where immunization

Image c/o The Seattle Times. Original can be found: https://static.seattletimes.com/wp-content/uploads/2015/03/dfbde78e-d7fb-11e4-8dd6-4df606469ca8-300x730.jpg

Image c/o The Seattle Times. via: SeattleTimes.com

rates have surged 27% higher than this time last year in the wake of the Disney measles outbreak.

This is remarkable news as immunization rates in Washington State have lagged behind the national average and in the past Washingtonians haven’t always responded to the resurgence of a deadly early childhood disease with the same gusto. A 2011/2012 whooping cough epidemic caused no increase in immunization rates, despite sickening 2,520 residents.

So what’s changed this time?

There are a few potential hypotheses, which include:

  1. The perceived severity of the illnesses, with whooping cough being viewed, not necessarily accurately, as “less severe” than the measles;
  2. Media coverage of the outbreak has been extensive and may have had an educational and awareness impact on parents;
  3. Parents that vaccinate have become much more vocal since the Disneyland outbreak, which may have helped change social norms in certain areas;
  4. A bill was introduced to the Washington State House (and was defeated) that would have removed the personal belief exemptions many parents use to not vaccinate, and this may have prompted parents to vaccinate before its potential passage.

So the short answer is: we don’t know what changed this time. My guess is that it’s a combination of the factors above, and I can’t wait to read the studies once they’re published!

If you’d like to learn more about immunization rates in Washington State, you can read the article from the Seattle Times: Measles vaccinations jump after scare, public dialogue.


 

Resources:

Resources:

JoNel Aleccia. Measles vaccinations jump after scare, public dialogue. The Seattle Times. March 31, 2014. Retrieved 4.2.15.

Rachel La Corte. Lawmaker aims to limit reasons for vaccine exemptions. The Seattle Times. February 4, 2015. Retrieved 4.2.15

Washington State Department of Health. News Release: State vaccination rates for children lag behind national average. September 12, 2013. Retrieved 4.2.15.

Wolf, E., Opel, D., DeHart, M. et al. Impact of a Pertussis Epidemic on Infant Vaccination in Washington State. Pediatrics. pp 456-464, September 2014. Retrieved 4.2.15

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Categories: Infectious Disease + Vaccines, Policy, Politics, + Pop Health