Viruses are the cause of a number of diseases. The flu, chicken pox and most common colds are just a few examples of diseases caused by viral infections.
While they may seem familiar, there is still much we don’t understand about viruses. For example, many bacterial infections can be treated with antibiotics, but few medicines are able to treat viral infections and these are rarely used.
Some viruses only affect particular species, but these viruses can evolve and jump to infect different species. This is what happened with swine flu a few years ago. The virus that causes swine flu originally affected pigs, but then started infecting humans.
Hendra and Nipah viruses – known as Henipaviruses – are two closely related viruses from fruit bats. Both viruses can infect humans and other animals. They are some of the deadliest viruses known, with mortality rates of over 70%.
While Nipah virus has only been reported in humans in South Asia, Hendra virus is native to Australia. There have been a number of Hendra outbreaks in Australia since 1994, with the most recent in 2011. These outbreaks have caused deaths in both humans and horses. Hendra virus is still poorly understood and it is not known why it is so dangerous to humans.
Until recently, Hendra and Nipah viruses were the only known Henipaviruses. Researchers from CSIRO and Biosecurity Queensland have recently identified a new Henipavirus, which they have called Cedar.
Ferrets and guinea pigs are two animals that are severely affected by Henipaviruses, however the research shows that they don’t get sick when infected with Cedar.
By comparing the genome of the Cedar virus with Henipaviruses, scientists may be able to identify the genes that make Hendra so dangerous to humans and horses. This information could lead to scientific discoveries that save lives.
Cells affected by Hendra virus (left) and Cedar virus (right). Hendra virus is much more effective at fusing cells together (as indicated by the red circles) and spreading the infection. Gary Crameri/CSIRO
Try this: Noodle bamboozle
You will need these materials.
Bring the water to the boil, and add the turmeric, noodles and flavouring.
Drain the cooked noodles and allow to cool. Don't worry if your noodles are a different colour.
Put on some rubber gloves, and dip the ends of the noodles into the 'acid' jar. What happens to the colour? Dip them into the 'base' jar - what happens now?
SAFETY: This activity uses a hot stove and hot water. See the CSIRO Education safety page for more information.
You will need
Turmeric
2 minute noodles, including flavouring sachet
Saucepan
Water
Sieve
Measuring cups and spoon
Vinegar
Sodium bicarbonate (Bicarb soda)
Jars
Stove
Rubber gloves
Marker
Labels
What to do
Place 2 cups of water in a saucepan and bring to the boil.
Add 2 tablespoons of turmeric to the saucepan. What colour is the water?
Add the noodles and flavouring sachet and cook for 2 minutes.
Drain the noodles with the sieve and allow them to cool. What colour are the noodles?
Label one jar ‘acid’ and another jar ‘base’.
Half fill the ‘acid’ jar with vinegar. Half fill the ‘base’ jar with water, add 2 teaspoons of bicarb soda and stir until dissolved.
When the noodles have cooled, put on some gloves. Pick up the noodles, and dunk the ends in the ‘acid’ jar. Remove the noodles. What do you observe?
Dip the ends in the ‘base’ jar. What happens?
What's happening
Turmeric is a vibrant, yellow spice commonly used in cooking. Turmeric gets its yellow colour from a chemical called curcumin. Curcumin is an acid-base indicator. This means that it changes colour depending on the pH of a substance.
pH is a measure of the acidity of a mixture. If a mixture has a pH of less than 7 it is acidic, and it is basic if the pH is greater than 7. A mixture with a pH of exactly 7 is said to be neutral (neither acidic nor basic).
Curcumin stays yellow in acidic mixtures. However, it turns a deep red colour in basic mixtures. The salts and flavourings in the noodles can make them slightly basic. This can turn the curcumin in the turmeric a red or orange colour.
Vinegar is an acid, so putting the noodles into vinegar turns the curcumin yellow again. Adding the curcumin to a basic bicarb soda solution turns it red.
Applications
pH is important in a range of fields, including medicine, chemistry, environmental science and food science. While pH is often measured accurately using electronic probes, indicators are still a quick and simple way to test pH.
One example is swimming pools. To prevent bacteria and other microbes growing in pool water, many pools are chlorinated. The concentration of chlorine has to be kept in a certain range, and its effectiveness depends on the water’s pH. Many pool testing kits use an indicator so that people can quickly and easily check to make sure the pH is in the correct range.
Send in your three-line poem to the RiAus sci-ku competition by 19 August for a chance to win a Kindle e-Reader. This year’s themes are farming and agriculture.
National Science Week
National Science Week is almost over but there are still plenty of events happening around the country. To find events in your local area head to the National Science Week website.
Quiz questions
1. What is the common name of the largest species of penguin? 2. What common pets are also known as cavies? 3. What happens to the boiling point of water as you rise above sea level? 4. What is the name of the rover that landed on the surface of Mars last week? 5. What common piece of medical equipment was first invented by René Laennec in 1816?
Websites
Watch it!
Instruments made for space need to survive a rough rocket ride, so they are tested before launch. Take a tour of a space shaker at Backstage Science.
See it!
New amphibian species are discovered frequently. Check out these pictures of some of the newest species.
Did you know?
Researchers have invented an ‘electronic nose’ to detect mesothelioma, a rare form of cancer often caused by exposure to asbestos.
Quiz answers
1. The Emperor Penguin is the largest species of penguin. 2. Cavies are also known as guinea pigs. 3. As you rise above sea level, the boiling point of water decreases. 4. The Mars rover is called Curiosity. 5. René Laennec invented the stethoscope in 1816. Research from Curtin University suggests that doctors wear stethoscopes during e-consultations to build trust with patients.
The LRET funds education, training and research programs in transportation, science, engineering, technology and the safety of life, worldwide for the benefit of all.
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