Week 8 ~ Say Hello to Measles

There is a current outbreak of measles in New York City that has spread to at least 21 people as of Tuesday, March 25, 2014. According to the city's Health Department, there are 10 pediatric cases and 11 adult cases. These cases range from three months to 63 years old. Amy Movius MD states in her article, "This year is shaping up to be the worst for measles cases in the US for many, many years" (2014). In 2000, measles was actually declared effectively eradicated from the United States. It did not circulate within our population due to the high vaccination rates of Americans. Now the disease is back, and unvaccinated people should highly consider becoming vaccinated.

3-D model of the measles virus

Measles, also known as rubeola, is a highly contagious respiratory disease caused by a virus, which shares the same name as the disease. This virus usually grows in the cells that line the back of the throat and lungs, and it can spread very easily through the air. It can also live on infected surfaces for up to 2 hours, so a person doesn't even need to be near an infected person in order to get sick. The onset of symptoms usually begins about 7-14 days after a person has been infected. In a typical case of measles, the infected individual may first experience a cough, fever (mild to moderate), red eyes, running nose, and sore throat. Tiny white spots (Koplik's spots) found inside the mouth may appear two or three days after the start of symptoms. A red or reddish-brown rash appears three to five days after symptoms begin. This rash normally develops on the individual's face near the hairline and will then spread down to the neck, trunk, arms, legs, and feet. Along with the rash, the infected person's fever may rise to 104 degrees Fahrenheit or higher.

A rash develops 3 to 5 days after symptoms begin

The measles vaccine didn't become available until the 1960s. Before then, there were 3 to 4 million cases per year in the United States. These large numbers of cases lead to about 500-600 deaths every year, and even many of the survivors ended up suffering from pulmonary and neurologic injuries caused by the infection. In the early 2000s, very little cases were reported each year, and all of those cases were brought back to the United States by individuals who had traveled to other countries where the disease still circulates. As years went on, though, more cases began to appear in the US. It was the worst in 2011, where there were 220 reported cases of measles. This rising number of cases is very likely due to more people choosing not to vaccinate. It is predicted that 2014 will surpass the number of cases in 2011; 80 cases have already been confirmed this year, and the outbreaks in NYC and other parts of the country will most likely continue to add to this number.

The outbreak in New York City began when measles was brought back to the US by unvaccinated individuals who had been traveling abroad. This goes to show how extremely important it is to be vaccinated. Someone may have traveled to another country for vacation or a business trip with no thought of contracting a disease, and now many others are infected because that person chose to travel abroad without being immunized. Once the measles virus was brought back to NYC, it was spread to many places including hospitals and health clinics, classrooms, different types of public transportation, and possibly airports and other large public places. The CDC has also tracked one individual who may have exposed the virus to up to 100 cancer patients. Of course it's a serious issue no matter who contracts measles, but cancer patients may have a much harder time combating the disease.

The majority of measles cases could have been avoided by a simple vaccination, so hopefully this outbreak has spread more awareness to how important being vaccinated really is. I have learned a lot more about measles just be reading about the outbreak in NYC. I did not know how extremely contagious it is. It can also lead to potentially fatal consequences like encephalitis and pneumonia. I feel that more people should be properly educated about this vaccine, and also informed of how quickly it spreads and the possible effects it can have on infected people.




References
1. Movius, A. (2014). Measles 2014: new reminders of old lessons. WABI TV5. Retrieved from http://wabi.tv/2014/03/25/measles-2014-new-reminders-old-lessons/
2. Mercogliano, A. (2014). NYC measles outbreak grows to 21 cases. PIX 11. Retrieved from http://pix11.com/2014/03/25/nyc-measles-outbreak-grows-to-21-cases/#axzz2x5GKwL1O
3. CDC. (2013). Overview of measles disease. Retrieved from http://www.cdc.gov/measles/about/index.html
4. Photo (top): http://img-new.cgtrader.com/items/19343/measles_virus_3d_model_max_48b80d2a-0fdc-46b7-807c-ed76e587e07f.jpg
5. Photo (2nd from top): http://classconnection.s3.amazonaws.com/624/flashcards/476624/jpg/clipboard05d.jpg
6. Photo (2nd from bottom): http://www.healthline.com/hlcmsresource/images/slideshow/mmr-vaccine/slide01_girl-getting-vaccine.jpg
7. Photo (bottom): http://www.gov.im/media/389484/measles_logo.jpg

Week 7 ~ Insect Sting Allergies

Hymenoptera venom allergy is simply an allergy to an insect sting. But to be more specific, it is "an immunoglobulin E (IgE)- mediated hypersensitivity to the venom of insects in the insect order Hymenoptera" (Paschall, 2014). I have always been interested in how some people don't have much of a reaction at all to a bee sting, while others could die without being treated. I don't know too much about this, though, so I thought it would be a good topic to research, especially why the allergy usually doesn't manifest until after the first couple stings. I have never been stung before, but for some reason I am not a big fan of bees, wasps, yellow jackets, etc. Whenever I happen to encounter one, I tend to overreact more than the average person probably does :) When I was younger I was always afraid of being allergic to them. My good childhood friend was very allergic to bees, so that is what probably caused me to be more paranoid about it.

Being stung by one of the insects in the order Hymenoptera can lead to systemic reactions. These types of reactions cause signs and symptoms throughout the body, some only mild while others life threatening. Mild systemic reactions may include flushing of the skin, uticaria (hives), and angioedema (swelling under the skin). More severe, or life-threatening, systemic reactions (also known as anaphylaxis) can include bronchospasm (a sudden constriction of the muscles in the walls of the bronchioles), laryngeal edema (a swelling caused by fluid accumulation in the soft tissues of the larynx), and hypotension. As stated in one source, "Venom-induced anaphylaxis can be particularly severe and is a leading cause of fatal anaphylaxis" (Tracy, 2013).

An insect sting allergy can develop at any age. Systemic reactions to Hymenoptera venom occur in about 3% of adults and in only about 1% of children younger than 17 years, which is interesting because children are stung more often than adults. Many of the reactions that children have are just mild, and large local reactions to stings are also more common in children (incidence of 20% for children and 10% for adults). The prevalence of insect sting allergy is twice as high in males as in females. This may be due to environmental factors such as increased exposure rather than genetic factors like inherent susceptibility. According to an online article from the Cleveland Clinic (2014), "There is no clear association with other allergies, and only 30% of patients with venom allergy are atopic. In addition, insect sting allergy is statistically not more likely to occur in persons with a family history of sting reactions." I found this last piece of information pretty interesting because I assumed it could be inherited.

In the United States, there are at least 50 deaths per year caused by insect sting reactions, and about one half of these deaths occur in victims with no prior history of a sting reaction. This number may be pretty large due to the fact that these people probably aren't as prepared to deal with the reaction since they have never experienced one before. Another interesting fact is that most fatalities (80%) occur in adults older than 40, and just 2% of fatalities occur in individuals younger than 20 years (Paschall, 2014). Perhaps the sting reactions grow worse over time or the body starts to become more sensitive to the venom as it ages. Another reason for this could be because older adults have obviously been alive longer, giving them more opportunities to have been stung more than once: "At least one prior sting is required to sensitize a person to venom, and sensitization is more likely to occur following multiple simultaneous stings or subsequent stings occurring over a relatively short period of time" (Paschall, 2014). Since an older person has been alive longer than a younger person, the older person is more likely to have had more sting reactions throughout his/her life compared to a child. The more severe reactions that one experiences, the higher his/her chance of fatality becomes.

It is crazy how the little stinger of a bee has the potential to cause such severe reactions in a person's body. The body is just trying to protect itself from the venom, but the immune system ends up overreacting and doing more harm than good. Thankfully these life-threatening systemic reactions are not common, but they are possible and do occur. As stated above, the two main risk factors for developing an insect sting allergy are 1) having multiple stings at one time and 2) being stung sequentially at close intervals. These two factors relate to an individual's environment, lifestyle, etc. rather than his/her biology such as the immune system. I was having trouble, though, finding more biology-related risk factors. For example, not everyone who experiences multiple stings at once ends up developing an allergy. So what makes them different from those who do develop the allergy?



References
1. Paschall, V. L. (2014). Hymenoptera venom allergy. Cleveland Clinic. Retrieved from http://www.clevelandclinicmeded.com/medicalpubs/diseasemanagement/allergy/hymenoptera-venom-allergy/
2. Tracy, J. M. (2013). Diagnosis of hymenoptera venom allergy. UpToDate. Retrieved from http://www.uptodate.com/contents/diagnosis-of-hymenoptera-venom-allergy
3. Photo (top): http://bee-stings.net/bee_stinger2.jpg
4. Photo (middle): http://pics.davesgarden.com/pics/2006/08/29/mygardens/40fec6.jpg
5. Photo (bottom): http://justoutsidetheboxcartoon.files.wordpress.com/2012/04/img_0605.jpg