I’m guessing that at this point, all of you have heard of the dreaded ebola virus. Just in the past few months, US citizens have been more concerned than ever about this horrific disease. In this blog, you will learn a little bit about the background of the ebola virus, as well as how diseases spread.
- First identified in 1976 in Congo near Ebola river.
- Then: 90% mortality
- Now: 50% mortality
How did ebola evolve to affect humans?
2014 Ebola Outbreak: Largest in HISTORY
- Ebola is now spreading in West Africa and concentrated in Guinea, Sierra Leone, and Liberia.
- The number of cases that have occurred during this outbreak have been more than the combined number of cases occurring previous to 2014 combined.
As you saw in the video, ebola spreads first from animal to human and then from human to human. Fruit bats, monkeys, gorillas and other primates become infected with ebola and become carriers. People may become infected with ebola by eating uncooked infected meat or coming in contact with infected animals. Once people are infected, they can infect other people by coming in contact with each other’s bodily fluids.
How is ebola contracted?
Although ebola has stayed out of the US in the past, it has recently made its way in, starting with a Texas man who was diagnosed on September 30th, 2014 and passed away on October 8th. The man had traveled from Liberia to Texas, so he was infected in Liberia before coming to the US. Since then, three others have been reported to have ebola. Two of these people who have contracted ebola have been health care workers from the Dallas, Texas, hospital where the first ebola patient was treated, and the third was a New York City doctor who had traveled to Guinea. Both Dallas patients have recovered and the New York City patient is currently being treated.
Why would health care providers be the ones to get ebola? Shouldn’t they knew the best way to stay healthy?
Health care providers are at a higher risk, since they are treating those who have ebola. Although ebola can only be spread through bodily fluids, treating someone who is vomiting could lead to infiltration of the disease through touching the infected person’s bodily fluids and then touching broken skin or mucus membranes such as the eyes. Health care providers treating patients with ebola have a much higher risk than the average US citizen, since they are in direct contact with the disease.
No! The reason ebola spreads so quickly and causes so many deaths in other countries is because they do not have adequate healthcare available to them. In the US, health care providers are not concerned about ebola spreading; as stated, ebola is difficult to contract in its present form and is easily stoppable when the right procedures are followed.
In order to help control the spread of diseases, teams of healthcare professionals work together to quarantine infected people, immunize people at risk, educate the public about prevention strategies, and treat infected people swiftly and aggressively.
Currently, there is no safe ebola vaccine.
Do I need to worry about getting ebola?
Although ebola is very dangerous, you most likely have no need to worry. It’s very difficult to actually get ebola, since you have to come in contact with an infected person’s bodily fluids and then get those bodily fluids in a mucus membrane such as your mouth, eyes, nose, etc. Ebola does NOT spread like a cold--you can’t get ebola from a sneeze or a cough--it’s not an airborne disease. Just like any other virus or disease, you can avoid ebola and help keep it from spreading by washing your hands, not sharing drinks, chapstick, etc., staying home if you are sick, and going to the doctor if you have symptoms.
And remember, only ebola victims with symptoms are infectious--the disease does not spread until the infected person is already showing symptoms.
The incubation period for ebola is 2-21 days. This means it may take 2-21 days to show symptoms of ebola. Therefore, if you come in contact with the disease, you should be on watch for about three weeks.
Quick look at ebola vs. the flu:
Simulation of how diseases spread:
YOU WILL NEED:
Lemon juice
Clear cups
Water
Paper
Writing utensils
A light source
Red and blue food coloring
Water droppers
An iron, and a heat-proof surface to use it on
YOU WILL DO:
- Get a group of twenty or so students together.
- Fill nineteen cups with water and one cup with lemon juice.
- Hand out the cups, paper, and water droppers to each participant, and don’t announce who has the lemon juice.
- Explain that there will be six one-minute rounds in this simulation.
- You may be wondering what lemon juice could have to do with infectious diseases. Lemon juice can actually be used as “invisible ink,” so the lemon juice represents the invisible infectious disease. One person has lemon juice in their cup, while others only have water. All participants should have a piece of paper with them for round one.
- Round 1: Give participants 60 seconds to move around the room; whenever they come in contact with each other, they should take a drop of water from the other’s cup and dot it on their piece of paper. This represents coming in contact with others’ body fluids.
- After the 60 seconds is up, use the iron on its hottest setting, and iron everyone’s papers. The heat from the iron will cause the lemon juice to turn brown. Those that came in contact with the lemon juice will have a brownish spot on their paper, while others will just have water spots. Those with the brown spot represent people who have been infected with the disease. Record the number of people who were infected.
Ok, so is this demonstration completely accurate? No! There was only one person spreading the disease. Let’s try something new!
8. Once again, all participants get a cup of water. This time, give one person a red dye dropper. Just like the lemon juice, the red dye represents the disease. Participants get 60 seconds to rotate around the room. The person with the red dye will put a drop of red dye in the cup of each student he or she comes in contact with. Those who receive a red drop will then also become disease carriers (equipped with red dye). They will continue to spread the disease by putting a drop of red dye into the cup of each person they encounter.
9. After 60 seconds, analyze how many people have pinkish-colored water--that’s how many now have the virus!
10. Create two graphs for round 1 and round 2 to demonstrate how many people became “infected” in each round. The Y-axis should be number of people, and X-axis should be time. How do they look different? Which round had more infected people? Which round more accurately demonstrates how quickly a virus can spread?
You should end up with something like this:
12. You could now have some people with red water (people infected with the disease), blue water (inoculated people who did not come in contact with the disease) or purple water (inoculated people who came in contact with the disease). Because inoculated people were protected from the virus, they do not count towards the infected number of people. Before moving on to round 4, record the number of infected students.
13. Round 4: This time, start by inoculating 40% of the class. If you have twenty people, eight should now start with blue water. Repeat step 8. Record the number of infected students.
14. Round 5: Start by inoculating 60% of the class. Repeat step 8. Record the number of infected students.
15. Round 6: Start by inoculating 80% of the class. Repeat step 8. Record the number of infected students.
16. Make a bar graph for rounds 2-6 and see how inoculation affects the spread of the disease.
You should end up with something like this:
References
- http://www.who.int/mediacentre/factsheets/fs103/en/
- http://www.cdc.gov/vhf/ebola/outbreaks/2014-west-africa/qa.html
- http://www.pbs.org/wgbh/nova/education/activities/3318_02_nsn.html
- http://www.seplessons.org/node/226
- http://youtu.be/qkzIGp1uYoc
- http://www.cdc.gov/vhf/ebola/outbreaks/2014-west-africa/index.html