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Malaria vaccines
What is malaria?
Malaria is a communicable disease caused by a protist.
Protists are not plants, animals, fungi, or bacteria. They are their own branch of life on Earth. To learn more about protists click here.
Malaria can be caused by several species of Plasmodium parasites, each of which has a complex life cycle (see illustration).
Parasites enter a host’s blood through the bite of an infected mosquito.
The parasites infect the host’s red blood cells, causing fever, joint pain, anemia, and fatigue.
Image from niaid.nih.gov
Where is malaria endemic?
Malaria is common in tropical and subtropical climates.
It is one of the most common infectious diseases on the planet.
It kills several million people each year, most of them children.
A tremendous amount of research has gone in to developing a malaria vaccine. Currently, scientists have developed one weak vaccine, that offer 25% to 50% protection. Further improvements are expected.
(from CK-12-Biology-Concepts/section/8.7)
Vector Biology
Malaria parasites are transmitted to human hosts by female mosquitoes of the genus Anopheles.
A diverse group of Anopheles (30 to 40 species) serves as vectors of human disease.
Disease Pathogenesis
So-called “uncomplicated” malaria entails a series of recurring episodes of chills, intense fever, and sweating. This sometimes includes other symptoms such as headache, malaise, fatigue, body aches, nausea, and vomiting.
In some cases, and especially in groups such as children and pregnant women, the disease can progress to “severe malaria.”
This includes cerebral malaria/coma, seizures, severe anemia, respiratory distress, kidney and liver failure, cardiovascular collapse, and shock.
Long-term impacts include death, disability, and significant socioeconomic burden on societies where the disease is prevalent.
Why haven’t we had effective malaria vaccines?
John Timmer writes
The disease is not caused by just a single infectious agent. Instead, Malaria comes from several related species in the Plasmodium genus.
Plasmodium falciparum typically causes more severe illnesses and has thus been the target of most vaccine efforts.
There are various regional strains that differ in ways that can be significant for immune system recognition.
Even a single strain doesn’t present an easy target for an immune response, though. The parasites undergo several distinct stages within the human body, with different proteins associated with each. And the parasite can alter other proteins on its surface to act as decoys that distract the immune system.
That said, researchers have gradually identified a handful of proteins that are consistently present on the surface of malarial parasites and are essential for their infectivity. That information has led to the development of vaccines that attempt to generate an immune response to these proteins.
More vaccine progress: This time, it’s malaria, John Timmer, Ars Technica, 6/30/2021
What progress has there been on malaria vaccines?
“We have word of the most effective malaria vaccine yet discovered. A year-long trial in Burkina Faso has shown 77% efficacy, which is by far the record, and which opens the way to potentially relieving a nearly incalculable burden of disease and human suffering.”
Great Malaria Vaccine News, AAAS, Derek Lowe, Science Translational Medicine, 4/23/2021
High Efficacy of a Low Dose Candidate Malaria Vaccine R21 in 1 Adjuvant Matrix-M™, with Seasonal Administration to Children in Burkina Faso, Mehreen S. Datoo et al., 4/20/2021 – Preprint, The Lancet
The Lancet, 2021. DOI: 10.1016/S0140-6736(21)00943-0
Nature, 2021. DOI: 10.1038/s41586-021-03684-z (About DOIs).
How is digital data stored and transmitted?
Next Generation Science Standards ask us to teach about digital transmission and storage of information:
Evaluate questions about the advantages of using digital transmission and storage of information.
Clarification Statement: Examples of advantages could include that digital information is stable because it can be stored reliably in computer memory, transferred easily, and copied and shared rapidly. Disadvantages could include issues of easy deletion, security, and theft.
From sfu.ca/~gotfrit/ZAP_Sept.3_99/d/digital.html
As a science teacher who enjoys learning about technology, I wholeheartedly agree. The questions are: How much about this should students learn? In what grades, and in what classes should they learn this? Will the school leadership support interdisciplinary collaboration between science, mathematics, and computer teachers in the district, to allow for the best possible pedagogy?
My informal survey of teachers reveals that many school districts don’t have much collaboration between middle-school and high-school teachers, nor much between HS teachers in different departments, Currently the only way that many students learn about these ideas is when a teacher, on their own, adds this topic as enrichment – within an already over-packed curriculum.
I suggest that we set up meetings between science, math, and coding teachers. And while we’re at – restore computer programming (“coding”) classes to the mainstream middle school curriculum!
Why Johnny Can’t Code. By David Brin
With such collaboration we can develop interesting lessons and resources. The basic ideas could be taught in 7th or 8th grade; they’d be reinforced in high school.
To be clear, not everyone needs to learn computer coding, hardware design, etc. Rather, all NGSS Standards say is that it is reasonable & important for citizens to understand the digital world in which we live. Our lives revolve around computers; the internet; smartphones; news, articles, and books readable on E-readers, tablets or computers; streaming audio, and streaming video.
As such, I would want students leaving high school to have some basic grasp of these ideas:
What are binary numbers?
Why do computers use binary at all? Why not just use “regular,” base 10 numbers?
Why do computers use base 2 instead of base 10? Base 10 Computers did use to exist
and
Why-do-computers-use-binary-numbers?
How are letters and words stored in digital form?
How can binary numbers represent non-numbers such as letters and symbols? Khan Academy
and
httHow does a computer convert text into binary or 0’s and 1’s?
and
Representing text, images and sound
How is audio and video stored in digital form?
How Digital Audio Works: From a list of numbers to the magic you hear
How is data physically stored?
(e.g. How does information get written to a hard drive, USB stick, DVD, etc.?)
Hard Drives: How Do They Work? TechBytes U Mass Amherst
How hard drives work. Computer Hope
How is data transmitted from one place to another?
How is data put on radio waves?
Is data – information – something physically real?
As it turns out, yes. All data has physical reality.
Is data physically real? Does data have mass?
Where did computers originally come from?
Their history goes back much further than most people realize.
Where did computers come from? A short history
NGSS Learning Standards
NGSS HS-PS4-2
Evaluate questions about the advantages of using digital transmission and storage of information.
Clarification Statement: Examples of advantages could include that digital information is stable because it can be stored reliably in computer memory, transferred easily, and copied and shared rapidly. Disadvantages could include issues of easy deletion, security, and theft.
Science and Engineering Practices: Asking Questions and Defining Problems
Asking questions and defining problems in grades 9–12 builds from grades K–8 experiences and progresses to formulating, refining, and evaluating empirically testable questions and design problems using models and simulations. Evaluate questions that challenge the premise(s) of an argument, the interpretation of a data set, or the suitability of a design.
Disciplinary Core Ideas – PS4.A: Wave Properties
Information can be digitized (e.g., a picture stored as the values of an array of pixels); in this form, it can be stored reliably in computer memory and sent over long distances as a series of wave pulses.
Crosscutting Concepts
Stability and Change: Systems can be designed for greater or lesser stability.
Connections to Engineering, Technology, and Applications of Science
Influence of Engineering, Technology, and Science on Society and the Natural World
* Modern civilization depends on major technological systems.
* Engineers continuously modify these technological systems by applying scientific knowledge and engineering design practices to increase benefits while decreasing costs and risks.
NGSS Evidence Statements
Students evaluate the given questions in terms of whether or not answers to the questions would:
i. Provide examples of features associated with digital transmission and storage of
information (e.g., can be stored reliably without degradation over time, transferred easily, and copied and shared rapidly; can be easily deleted; can be stolen easily by making a copy; can be broadly accessed);
In their evaluation of the given questions, students:
i. Describe the stability and importance of the systems that employ digital information as they relate to the advantages and disadvantages of digital transmission and storage of information; and
ii. Discuss the relevance of the answers to the question to real-life examples (e.g., emailing your homework to a teacher, copying music, using the internet for research, social media).
When buildings collapse: analysis of structural failures
Engineering is the use of physics to safely design buildings, vehicles, or infrastructure.
Basic idea: Loads on architectural and civil engineering structures
Structural loads are an important consideration in the design of buildings.
Building codes require that structures be designed and built to safely resist all actions that they are likely to face during their service life.
Minimum loads are specified in these building codes for types of structures, geographic locations, usage and building materials.
A famous example of why we need to understand and calculate forces correctly is the Ponte Morandi (Morandi Bridge) bridge collapse. This was a bridge in Genoa, Italy, constructed in the 1960s over the river Polcevera. In 2018, it collapsed during a rainstorm. 43 people died. This led engineers to engage in extensive analysis of the structural failure.
This diagram shows how engineers use physics – forces and vectors – to model the stress and load on every part of a structure.
from the New York Times article, Genoa Bridge Collapse:
The Road to Tragedy. 9/6/2018
Structural loads are split into categories by their originating cause. In terms of the actual load on a structure, there is no difference between dead or live loading, but the split occurs for use in safety calculations or ease of analysis on complex models.
We have to take many kinds of loads into consideration:
Dead loads, Live loads, Environmental loads,
Changes in loads due to
• Foundation settlement or displacement
• Fire
• Corrosion
• Explosion
• Creep (tendency of a solid material to move slowly or deform permanently under the influence of persistent mechanical stresses)
• Impact from vehicles or machinery vibration
• Construction loads
(This section adapted from Structural load, Wikipedia.)
As science teachers we can use news events about structural collapse to illuminate NGSS Phenomena; this is a storyline approach to teaching physics.
Such phenomenon tie into:
Dynamics – the study of forces and their effects on motion. In high school we learn about this as “Forces” and “Newton’s laws of motion.”
Vectors are ways of showing the magnitude and direction of forces.
Mechanical equilibrium: If civil engineering was religion, the first commandment would be: “Thou shalt always have static equilibrium.” The principle is simple: the sum of all the forces acting on a structure should come to zero.
Free body diagrams – The simplest way to understand how objects are affected by forces: free body diagrams.
Surfside Condominium Florida collapse, 2021
‘Something Off’: Miami Collapse Complex Had Issues, Justin Rohrlich and Zoe Richards, The Daily Beast, 6/25/2017
The Champlain Towers complex was the subject of at least one lawsuit, and it attracted the attention of scientists alarmed over land erosion.
9/11 terrorist attack and destruction of the World Trade Center, 2001
The September 11 attacks, often referred to as 9/11, were a series of four coordinated terrorist attacks by the Wahhabi Islamist terrorist group Al-Qaeda against the United States. This occurred on the morning of Tuesday, September 11, 2001.
FEMA Chapter 2. World Trade Center Building Performance Study: Data Collection, Preliminary Observations, and Recommendations. FEMA 403, May 2002
Image above from FEMA Chapter 2. World Trade Center Building Performance Study: Data Collection, Preliminary Observations, and Recommendations. FEMA 403, May 2002
Engineering analysis of the destruction. Addressing conspiracy theories
Boston, Massachusetts area events
2000 Commonwealth Avenue collapse (in 1971)
Failure case studies – 2000 Commonwealth Avenue, Boston
Collapse of 2000 Commonwealth Avenue: Punching Shear Case Study
Punching shear is usually the critical failure mechanism for flat slab reinforced concrete structures. This mechanism is illustrated in Fig. 5. With this type of failure, the column and part of the slab punch through the slab as it moves downward.
The force acting on the slab around a column overcomes the resistance and the slab falls down around the column. A portion of the slab is left around the column, but the remainder of the slab falls to the next floor. If the lower slab is unable to hold up both floors, then a progressive collapse will begin.
Also, punching shear redistributes forces acting on the failed slab to other columns. If the other columns cannot carry the added weight, then the slab will start punching through the surrounding columns as well. Punching shear at one column can initiate a complete failure of a building.
When the Pickwick Club Collapse Killed 44 in Boston; the Charleston Took the Blame, event in 1925, New England Historical Society
Related articles
Making a Difference when Disaster Strikes: Structural Engineering Emergency Response
William C. Bracken, Structure magazine, 2/2018
Learning from Disasters, Jessica Mandrick, Structure magazine, 11/2016
Structural integrity and failure, Wikipedia
Learning Standards
2016 Massachusetts Science and Technology/Engineering Curriculum Framework
HS-PS2-1. Analyze data to support the claim that Newton’s second law of motion is a mathematical model describing change in motion (the acceleration) of objects when acted on by a net force.
HS-PS2-10(MA). Use free-body force diagrams, algebraic expressions, and Newton’s laws of motion to predict changes to velocity and acceleration for an object moving in one dimension in various situations
2016 High School Technology/Engineering
HS-ETS1-1. Analyze a major global challenge to specify a design problem that can be improved. Determine necessary qualitative and quantitative criteria and constraints for solutions, including any requirements set by society.
HS-ETS1-2. Break a complex real-world problem into smaller, more manageable problems that each can be solved using scientific and engineering principles.
HS-ETS1-3. Evaluate a solution to a complex real-world problem based on prioritized criteria and trade-offs that account for a range of constraints, including cost, safety, reliability, aesthetics, and maintenance, as well as social, cultural, and environmental impacts.
HS-ETS1-4. Use a computer simulation to model the impact of a proposed solution to a complex real-world problem that has numerous criteria and constraints on the interactions within and between systems relevant to the problem.
HS-ETS1-5(MA). Plan a prototype or design solution using orthographic projections and isometric drawings, using proper scales and proportions.
HS-ETS1-6(MA). Document and present solutions that include specifications, performance results, successes and remaining issues, and limitations.
A FRAMEWORK FOR K-12 SCIENCE EDUCATION: Practices, Crosscutting Concepts, and Core Ideas
PS2.A: FORCES AND MOTION
How can one predict an object’s continued motion, changes in motion, or stability?
Interactions of an object with another object can be explained and predicted using the concept of forces, which can cause a change in motion of one or both of the interacting objects… At the macroscale, the motion of an object subject to forces is governed by Newton’s second law of motion… An understanding of the forces between objects is important for describing how their motions change, as well as for predicting stability or instability in systems at any scale.
How many moons does Earth have?
How many moons (or natural satellites) does Earth really have?
Most people say that we have one moon, Luna. Yet there are some other objects in space have moon-like motions. We need to understand the question better: what exactly is a “moon”?
Look through astronomy and physics textbooks; they rarely agree with other on the definition. Why?
In our article on moons we learn that people first used the word moon for just one example (Luna.) But in later millennia we began using this word for other objects in our solar system (moons of Jupiter, of Saturn, etc.) Much later, many astronomers used this word for some very different kinds of objects.
So how should we define a moon?
We have options. We could define a moon in any of these way:
• Compositionally (what they are made of)
• How they were formed
• Kinematically: defined by their orbit, pattern of motion
There is some consensus on this issue; almost all definitions of moons have to do with their motion around a planet (the dynamic and kinematic option.) So a definition based on this is what we explore here.
Below we see Luna orbiting the Earth.
A NASA camera aboard the Deep Space Climate Observatory (DSCOVR) satellite captured a unique view of the moon as it moved in front of the sunlit side of Earth last month. The series of test images shows the fully illuminated “dark side” of the moon that is never visible from Earth.
The images were captured by NASA’s Earth Polychromatic Imaging Camera (EPIC), a four megapixel CCD camera and telescope on the DSCOVR satellite orbiting 1 million miles from Earth. From its position between the sun and Earth, DSCOVR conducts its primary mission of real-time solar wind monitoring for the National Oceanic and Atmospheric Administration (NOAA).
https://www.nasa.gov/feature/goddard/from-a-million-miles-away-nasa-camera-shows-moon-crossing-face-of-earth
Moons defined by simple orbit around a planet
A moon is a large natural body (rock, metal, etc.) that orbits around a planet.
A moon orbits within that planet’s Hill sphere (see below.)
This is the most common definition of a moon.
Newton’s canon, one of the most famous Gedankenexperiment (thought experiments) in physics is something you should study. When you understand how this leads to an object orbiting Earth (or in principle, orbiting any planet) then you have the classic – and perfectly fine – definition of a moon.
If you look into advanced physics we can say that a “moon” is a natural body orbiting a planet when it is within that planet’s Hill sphere. A Hill sphere is the region in which a planet’s gravity dominates the attraction of satellites.
Hill Sphere, the moon’s orbit and debunking flat earth theories
On a related note, what is the path of the moon around the Earth? A nearly-circular ellipse.
Moon_orbit.jpg, Wikipedia
Now ask – What is the path of the moon around the Sun?
The moon orbits Earth, yet at the same time, the Earth orbits the Sun. What would it look like if we want far above our Sun’s north pole, way out in space, and looked down at the motion of both the moon and the Earth, over the course of a year?
Luna’s path would trace out a convex curve like this:
The above image is exaggerated to bring out detail.
When we draw the path to scale (below) we see that the actual deviation from a circle is rather small.
from Does the Moon Orbit the Sun or the Earth? Wired magazine
Can moons have moons?
Can a moon have their own moons orbiting them? Apparently so!
Guess what scientists call the moons of moons, Quartz
Why Don’t Moons Have Moons? Medium
Can Moons Have Moons?
Objects at Lagrange points
Lagrange points are solutions to the famous “three body problem” –
Someone asked, hey if we have two objects in space (e.g. the Sun and the Earth) is there any place we could put a third object where the pull from those two bodies cancels out?
The Italian-French mathematician Josephy-Louis Lagrange used math to solve this problem; he discovered that for any three body system there were always five solutions (five special places in space.)
Objects at these points are stable. Unless, of course they are disturbed by some other force. (*)
(*) Over the long term (sometimes years, sometimes millennia) objects here are not perfectly stable. There always is a small external force disturbing them: the gravity from other planets and asteroids in our solar system. So in practice, a spaceship in those Lagrange spots occasionally need a bit of thrust to keep them in place.
Objects at Sun-Earth LaGrange points
Earth-Sun Lagrange points are where the gravitational pull of the Sun and Earth cancel each other out
Below we our sun, Sol, in yellow, and Earth in blue. The Lagrange points are labelled 1 through 5.
Only L1 and L2 are near Earth; L4 and L5 are many millions of miles away, and L3 is always on the other side of the Sun, relative to us.
There are objects in space in these positions, including some man-made satellites.
Such objects are not considered moon’s of Earth, although they are locked on the Sun-Earth motion.
Objects at Earth-Moon LaGrange points
Earth-Moon Lagrange points are where the gravitational pull of the Earth and Moon cancel each other out.
from 3D4U
Sure, objects in these orbits might be considered natural satellites or moon of Earth.
But perhaps we should clarify that they are in a separate category from the “usual” definition of an orbit.
Earth Moon Lagrange points video by 3D4U
Quasi-satellites
This term refers to near Earth asteroids that have their own orbit around the Sun, but over time these ones have developed a 1:1 resonance with Earth’s orbit
Their orbits are unstable over “short” periods of time – they develop other orbital resonances, or are kicked out of such patterns over a period of centuries or millennia.
The most well known quasi-satellite of Earth is the asteroid Cruithne, discovered in 1986. It is 5 KM in diameter.
If you were “above” our Sun, looking down into the solar system then you would see it’s orbit and Earth’s orbit like this:
image from Wikipedia
But from the point of view of people here on Earth, it appears to be trailing us, making a horseshoe-shaped orbit.
That’s not a moon as such, and it doesn’t even orbit us. But due to the oddities of orbital mechanics it appears to be behind us in space, orbiting empty space!
image from Wikipedia
Much more moon-like is the orbit of asteroid 469219 Kamoʻoalewa. Originally designated 2016 HO3.
What we see here is its path as seen from observers on Earth.
This is a small asteroid of the Apollo group, approx 41 meters (135 feet) in diameter. This is the smallest, closest, most stable (known) quasi-satellite of Earth.
Animation from JPL-CALTECH/ NASA
Here we see the orbit of asteroid AA29 2002, as seen from Earth. One can immediately see why people might consider an object like this to be a small moon.
From our point of view it indeed appears to be following and orbiting our world, although it is really like the above cases, an independent asteroid in resonance with us.
cneos.jpl.nasa.gov/doc/2002aa29/
Key difference between a true satellite and a quasi-satellite
(A) True satellites/moons simply orbit the Earth (or whatever other planet they orbit.) If the Earth hypothetically disappeared then the moon would fly off into a very different orbit around the Sun.
(B) But the orbit of one of Earth’s quasi-satellites wouldn’t change much if the Earth hypothetically disappeared. The quasi-satellite is independently orbiting the Sun.
External resources
https://en.wikipedia.org/wiki/Lagrange_point
Teaching three dimensional geometry in high school
Most school districts still make students master a one-size-fits all sequence of geometry topics and skills that is largely unchanged since the 1800s. Does this inspire students to love math, become mathematicians, engineers, or physicists? Does it provide the mathematical literacy necessary for people to function in society?
The endless system of curriculum reforms over the last century (*) hasn’t helped achieve either goal. Some students do fall in love with math and science, but usually in spite of curriculums, not because of them.
School districts are pressured to have standardized state exams. Some pressure is from parents who think that good education means doing it the same way that it always has been done. (And to be sure, it is important to have mastery of some basic geometry topics.) Yet most pressure is from politicians. How? Textbook publishing companies give campaign donations to politicians; they want them to enact a constant stream of new curricula so they can sell new learning materials and tests. Students are stuck in a system in which the voices of expert math and science teachers are minimized.
How does this issue relate to geometry in specific? Students are relentlessly drilled on two dimensional geometry, and how to construct proofs. Many students dread this; they find it disconnected from daily life, devoid of fun, and not instilling any sense of wonder.
Yet when we talk to actual mathematicians we learn that they they investigate interesting and fun problems in geometry; they find almost mystical connections between the laws of math and laws of the universe itself; and they use geometry not in two dimensions, but in three.
They use geometry for engineering and building; machining and 3D printing parts, metalwork, and tools; they use 3D polygon design for computer programming and making video games.
Where is all of this in our schools? It is time to listen to math teachers, mathematicians, and people who use these ideas for work or art. We should reduce the amount of time we spend on geometry proofs, and increase the use of fun, interesting and practical 3D geometry.
– Robert Kaiser
(*) Left Back: A Century of Battles over School Reform, Diane Ravitch
Presented below is an example of transforming two dimensional geometry into three dimensional geometry, which has applications in sports, engineering, and videogames.
First, consider regular, convex polygons Mathsisfun.com Regular polygons
Here are the basic regular and irregular polygons.
from skillsyouneed.com
Now consider shapes in three dimensions: A polyhedron (plural polyhedra or polyhedrons) is a 3D shape with flat polygonal faces, straight edges and sharp corners or vertices.
The five convex examples have been known since antiquity and are called the Platonic solids:
The triangular pyramid or tetrahedron, cube, octahedron, dodecahedron and icosahedron:
Look at 2D pentagons and hexagons – consider: Do they tile together without gaps or overlaps?
If so then show us…. But if not then how can we get such tiles to fit tightly without overlap or gaps?
We need to assemble them together into a 3D structure. What do we mean by 3 dimensional?
Photo by RK
Questions: How many tiles of each type will we need? How do we arrange them? Is there more than way to do this, or just one way?
Procedure
Give students hexagon and pentagon templates (on heavy card stock.)
They will trace multiple copies of each one onto card stock or construction paper.
Carefully cut out all of these pieces. Assemble them together into a 3D structure with a regular, repeating pattern. The resulting shape should have no gaps or overlap.
Animation by Friedrich Lohmüller
How do we use geometry in real life
Geometry in real life: careers and at home
Related readings
The (Math) Problem With Pentagons.
“Three pentagons at a vertex gives us 324 degrees, which leaves a gap of 36 degrees that is too small to fill with another pentagon. And four pentagons at a point produces unwanted overlap. No matter how we arrange them, we’ll never get pentagons to snugly match up around a vertex with no gap and no overlap. This means the regular pentagon admits no monohedral, edge-to-edge tiling of the plane.”
The (Math) Problem With Pentagons. Triangles fit effortlessly together, as do squares. When it comes to pentagons, what gives? Patrick Honner, Quanta Magazine, 12/11/2017
Two-Dimensional Math In a Three-Dimensional World, Marjorie Senechal & George Fleck, Education Week, 2/6/1985
Week Five: Make Something Big, Daniel B. Rosenberg
Building a buckyball, PBS NOVA
Learning Standards
Common Core Math – Geometric Measurement and Dimension
• Explain volume formulas and use them to solve problems
• Visualize relationships between two-dimensional and three-dimensional objects
CCSS.MATH.CONTENT.HSG.MG.A.3
Apply geometric methods to solve design problems (e.g., designing an object or structure to satisfy physical constraints or minimize cost; working with typographic grid systems based on ratios).*
Appendix A Common Core Math, Unit 3: Extending to Three Dimensions
Visualize the relation between two dimensional and three-dimensional objects.
Apply geometric concepts in modeling situations.
National Council of Teachers of Mathematics, Standards and Positions
Grades 9–12 Expectations: In grades 9–12 each and every student should – Analyze properties and determine attributes of two- and three-dimensional objects; Explore relationships (including congruence and similarity) among classes of two- and three-dimensional geometric objects, make and test conjectures about them, and solve problems involving them.
Influenza vaccine
“Flu” is short for “influenza virus”.
How are influenza vaccines made?
The US CDC and other labs partner with the World Health Organization (WHO) to choose certain virus strains to send to private vaccine manufacturers.
The flu can mutate and strains can change each year, meaning new vaccines are needed for every flu season.
The selected virus is injected into a fertilized hen’s eggs, where it incubates and replicates for a few days — just as it would do inside a human host.
Scientists then harvest fluid containing the virus from the egg.
They inactivate the virus so it can no longer cause disease, and purify it, leaving scientists with the virus antigen.
The antigen is the crucial element — it’s a substance released by the virus that triggers your immune system to respond. That’s how the vaccine prepares your immune system for a real infection.
The entire process, from the arrival of the egg to the publicly available vaccine, takes at least six months, according to the CDC.
Graphic by Jason Kwok, CNN article, with info from US CDC
Why does the flu vaccine seem to make some people sick?
Vaccines merely stimulate our immune system, which temporarily creates non-specific responses. For example, redness, swelling, small increase in body temperature.
These are not a sign of infection. Rather, they are the normal signs that your body is developing defenses against the antigen.
How effective is the influenza vaccine?
How effective are influenza vaccines?
No one claims that vaccines are 100% effective. No medical technique is 100% effective. Most vaccines are very effective, usually over 90% effective.
However, that is not yet the case for flu vaccines. The flu virus evolves through natural selection, like all viruses and life, and it happens to evolve very quickly.
“CDC conducts studies each year to determine how well the influenza (flu) vaccine protects against flu illness. While vaccine effectiveness can vary, recent studies show that flu vaccination reduces the risk of flu illness by between 40% and 60% among the overall population during seasons when most circulating flu viruses are well-matched to the flu vaccine. In general, current flu vaccines tend to work better against influenza B and influenza A(H1N1) viruses and offer lower protection against influenza A(H3N2) viruses.”
Vaccine Effectiveness – How Well Does the Flu Vaccine Work? CDC (Centers for Disease Control)
So if it isn’t perfect, why use this vaccine at all?
Excerpted from the CDC article:
Keeps you from getting sick with flu.
Reduces risk of flu-associated hospitalization, including among children and older adults.
Flu vaccination lowers rates of some cardiac (heart) events among people with heart disease
Reduces chances of being hospitalized among people with diabetes (79%) and chronic lung disease (52%).
Helps protect women during and after pregnancy. Getting vaccinated can also protect a baby after birth from flu. (Mom passes antibodies onto the developing baby during her pregnancy.)
Vaccination reduced the risk of flu-associated acute respiratory infection by about one half
Significantly reduces a child’s risk of dying from influenza.
It can make your illness milder even if you do get sick.
Most importantly, it protects people around you, including those who are more vulnerable to serious flu illness, like babies and young children, older people.
.
Why don’t we yet have a vaccine for HIV/AIDS?
Intro – What is HIV?
HIV (human immunodeficiency virus) is a virus that attacks cells that help the body fight infection, making a person more vulnerable to other infections and diseases.
It is spread by contact with certain bodily fluids of a person with HIV, most commonly during unprotected sex (sex without a condom or HIV medicine to prevent or treat HIV), or through sharing injection drug equipment.
HIV leads to the disease AIDS (acquired immunodeficiency syndrome).
The human body can’t get rid of HIV and no effective HIV cure exists. So, once you have HIV, you have it for life.
from HIV.Gov
HIV infecting a human cell. Credit: NIH Image Gallery
HIV/AIDS vaccine: Why don’t we have one after 37 years, when we have several for COVID-19 after a few months?
Ronald C. Desrosiers writes
HIV has evolved an ability to generate and to tolerate many mutations in its genetic information. The consequence of this is an enormous amount of variation among strains of the virus not only from one individual to another but even within a single individual.
Let’s use influenza for a comparison. Everyone knows that people need to get revaccinated against influenza virus each season because of season-to-season variability in the influenza strain that is circulating.
Well, the variability of HIV within a single infected individual exceeds the entire worldwide sequence variability in the influenza virus (*) during an entire season.
What are we going to put into a vaccine to cover this extent of strain variability?
HIV has also evolved an incredible ability to shield itself from recognition by antibodies. Enveloped viruses such as coronaviruses and herpes viruses encode a structure on their surface that each virus uses to gain entry into a cell.
This structure is called a “glycoprotein,” meaning that it is composed of both sugars and protein.
But the HIV envelope glycoprotein is extreme. It is the most heavily sugared protein of all viruses in all 22 families. More than half the weight is sugar.
And the virus has figured out a way, meaning the virus has evolved by natural selection, to use these sugars as shields to protect itself from recognition by antibodies that the infected host is trying to make. The host cell adds these sugars and then views them as self.
These properties have important consequences relevant for vaccine development efforts. The antibodies that an HIV-infected person makes typically have only very weak neutralizing activity against the virus.
Furthermore, these antibodies are very strain-specific; they will neutralize the strain with which the individual is infected but not the thousands and thousands of other strains circulating in the population.
Researchers know how to elicit antibodies that will neutralize one strain, but not antibodies with an ability to protect against the thousands and thousands of strains circulating in the population. That’s a major problem for vaccine development efforts.
HIV is continually evolving within a single infected individual to stay one step ahead of the immune responses. The host elicits a particular immune response that attacks the virus. This puts selective pressure on the virus, and through natural selection a mutated virus variant appears that is no longer recognized by the individual’s immune system. The result is continuous unrelenting viral replication.
Life cycle of HIV
Source: HIV/AIDS vaccine: Why don’t we have one after 37 years, when we have several for COVID-19 after a few months? By Ronald C. Desrosiers, TheConversation.com, 5/17/2021
(*) Evolutionary and immunological implications of contemporary HIV-1 variation
Bette Korber, Brian Gaschen, Karina Yusim, Rama Thakallapally, Can Kesmir, Vincent Detours
British Medical Bulletin, Volume 58, Issue 1, September 2001, Pages 19–42, https://doi.org/10.1093/bmb/58.1.19
Learning Standards
Massachusetts Comprehensive Health Curriculum Framework
Students will gain the knowledge and skills to select a diet that supports
health and reduces the risk of illness and future chronic diseases. PreK–12 Standard 4
8.1 Describe how the body fights germs and disease naturally and with medicines and
immunization
8.2 Identify the common symptoms of illness and recognize that being responsible for individual health means alerting caretakers to any symptoms of illness.
8.5 Identify ways individuals can reduce risk factors related to communicable and chronic diseases
8.6 Describe the importance of early detection in preventing the progression of disease.
8.7 Explain the need to follow prescribed health care procedures given by parents and health care providers.
8.8 Describe how to demonstrate safe care and concern toward ill and disabled persons in the family, school, and community.
8.13 Explain how the immune system functions to prevent and combat disease
Interdisciplinary Learning Objectives: Disease Prevention and Control
8.a. (Law & Policy. Connects with History & Social Science: Geography and Civics &
Government) Analyze the influence of factors (such as social and economic) on the treatment and management of illness.
Benchmarks for Science Literacy, AAAS
The immune system functions to protect against microscopic organisms and foreign substances that enter from outside the body and against some cancer cells that arise within. 6C/H1*
Some allergic reactions are caused by the body’s immune responses to usually harmless environmental substances. Sometimes the immune system may attack some of the body’s own cells. 6E/H1
Some viral diseases, such as AIDS, destroy critical cells of the immune system, leaving the body unable to deal with multiple infection agents and cancerous cells. 6E/H4
Vaccines induce the body to build immunity to a disease without actually causing the disease itself. 6E/M7** (BSL)
This website is educational. Materials within it are being used in accord with the Fair Use doctrine, as defined by United States law.
§107. Limitations on Exclusive Rights: Fair Use. Notwithstanding the provisions of section 106, the fair use of a copyrighted work, including such use by reproduction in copies or phone records or by any other means specified by that section, for purposes such as criticism, comment, news reporting, teaching (including multiple copies for classroom use), scholarship, or research, is not an infringement of copyright. In determining whether the use made of a work in any particular case is a fair use, the factors to be considered shall include: the purpose and character of the use, including whether such use is of a commercial nature or is for nonprofit educational purposes; the nature of the copyrighted work; the amount and substantiality of the portion used in relation to the copyrighted work as a whole; and the effect of the use upon the potential market for or value of the copyrighted work. (added pub. l 94-553, Title I, 101, Oct 19, 1976, 90 Stat 2546)
How to be an ally to Jewish students and families
Over the last decade antisemitism has increased dramatically in the United States. An increasing number of students in public schools and colleges report being made to feel unwelcome or unsafe; violent attacks and death threats have been on the rise.
Jews in America are the target of 60 percent of all religiously motivated hate crimes in the US. This is despite Jewish people constituting a mere two percent of the population, newly released FBI statistics for 2020 have shown.
“New data analysis of the just-released FBI hate crime statistics uncovers a disturbing trend in the United States: Jews are at least three times more likely to experience a hate crime in America than any other ethnic group.
The Federal Bureau of Investigation recently released its Hate Crime Statistics Report highlighting troubling trends related to hate crimes against Jews. According to the report, Jewish people were the targets of over 60% of religious bias-related hate crimes. Jews were targeted at significantly higher rates than any other religious group.
This data indicates an increase of 41% since 2015. Over the past decade, hate crimes targeting Jews topped the charts every year, with rates ranging from 52% to 67% of the total religious bias crimes.
Factoring in the relative proportion of Jews from the total US population, this analysis highlights an alarming result: A Jewish person is three times more likely to experience a hate crime than African Americans and thirteen times more likely than Hispanic Americans.
These comparisons are not intended to diminish anyone’s suffering; however, these numbers are alarming and require deep evaluation. Antisemitic rhetoric, vandalism, and intimidation have become normalized in the US in recent years. Whether it takes place on social media, in the public square, or even in Congress. It is no wonder that such trends would escalate to violent hate crimes against Jewish people on the streets, in our places of worship, and even in our homes.”
Jews are top target for hate crimes in US, FBI data shows
As teachers we have an obligation to insure that all of our students and their families are safe and welcome in our schools.
Teachers of all backgrounds work to understand students of all backgrounds, and we learn to recognize bigotry so that we can keep that out of our schools.
An important point in being an anti-racist is listening to voices. Make space to learn from the lived experiences of our Jewish students and their families.
A Jewish Resistance to antisemitism
Antisemitism Stories
Antisemitism Today
ChallahBackGirls – perspective from Jewish teens
Jewish On Campus
Stop Antisemitism
This Modern Jew
“You Don’t Look Jewish”
Being anti-racist includes being an anti-antisemite.
No one is born racist or antiracist; these result from the choices we make. Being antiracist results from a conscious decision to make frequent, consistent, equitable choices daily. These choices require ongoing self-awareness and self-reflection as we move through life. In the absence of making antiracist choices, we (un)consciously uphold aspects of white supremacy, white-dominant culture, and unequal institutions and society. Being racist or antiracist is not about who you are; it is about what you do.
– Talking About Race. Being Antiracist. National Museum of African American History and Culture, Smithsonian
“To be antiracist is a radical choice in the face of history, requiring a radical reorientation of our consciousness.”
Ibram Kendi, “How to be an Antiracist”
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Include Jews in your activism
By Isabel Liang
Antisemitic Incidents: Being an Ally, Advocate and Activist, ADL
Include Jews in Your Activism
An unheard hatred: how anti-Semitism is dangerously ignored
It’s Time for Intersectionality to Include the Jews
Start Including Jewish People In Your Activism, Her Campus
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Best Practices When Teaching About Native American Peoples
Some helpful links:
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Indigenous peoples of the Americas, the pre-Columbian peoples of North and South America and their descendants
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Native Americans in the United States
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Indigenous peoples in Canada, the indigenous peoples of Canada
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First Nations, indigenous Canadians who are neither Inuit or Métis
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Inuit, indigenous peoples inhabiting the Arctic region
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Métis in Canada, people who trace their descent to indigenous First Nations peoples and European settlers
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Learning Standards
Toward Responsibility: Social Studies Education that Respects and Affirms Indigenous Peoples and Nations, National Council for the Social Studies, 3/2018
The National Council for the Social Studies recognizes the responsibility of social studies education to respect and affirm Indigenous peoples, nations, and sovereignty. NCSS supports the creation and implementation of social studies curricula that explicitly present and emphasize accurate narratives of the lives, experiences, and histories of Indigenous Peoples, their sovereign Nations, and their interactions—past, present, and future—with Euro-American settlers and the government of the United States of America.
Glycans (polysaccharides and oligosaccharides)
Glycans are polymers of individual sugar molecules (monosaccharides)
Here’s a glucose, a simple sugar monomer (single unit.) Note that there are also many other types of sugars.
What’s the difference between monomers and polymers?
Living things can link many sugars together into a polymer – a glycan.
Here’s one example:
Glycans are made by all living things and by many viruses.
Glycans can be free (not bonded to anything else.) In this state they are often used to store chemical energy, or as building blocks for plant cell walls.
Glycans can be bonded together with a protein or a lipid. In such cases they have specific jobs.
• When bonded with a protein they’re called glycoproteins.
• When bonded with a lipid they’re called glycolipids.
Types of glycans
Cellulose – glucose monosaccharides linked to one another in a long, linear chain.
Used for structural support in cell walls of plants and algae.
Trees and plants use these glycans as building blocks.Here we see them linking together until they build the structure of a leaf, a stem, or branch.
From Direct evidence for α ether linkage between lignin and carbohydrates in wood cell walls, Hiroshi Nishimura et al, Scientific Reports volume 8, Article number: 6538 (2018)
Starch is made in plants. This molecule is used for energy storage.
Glycogen – used for energy storage in fungi and animals.
Comparison of cellulose, starches, and glycogen
from coredifferences.com
Uses of glycans in the body
In breast milk
Human milk oligosaccharides are found in breast milk.
Human milk oligosaccharides(HMOs)
On cell membranes
They are found in cell membranes (lipid bilayers) as glycans attached to proteins – glycoproteins.
Gly-tech.com
Immune system
I don’t know if any glycoproteins evolved to be part of the immune system, but I do know that they became a part of the immune system – various pathogens can recognize some glycans and use them as part of a pathway to infect a cell. Some antibodies interact with them.
Uses in bacteria
We find peptidoglycan in bacterial cell walls.
From Prescott’s Microbiology, McGraw Hill
Medical uses
They are valuable diagnostic and therapeutic targets.
How to draw glycans, the exact way
On the left we see a skeletal drawing of a single sugar molecule, glucose. In the middle we see two sugars bonded together to make a sucrose molecule. (disaccharide, i.e. a molecule with 2 sugars.)
On the right we see a starch, which is a more complex structure of several sugars covalently bonded.
On the bottom we see a much more complex assembly of sugar molecules bonded together N-Glycan, in this case mostly a bunch of sucrose molecules bonded together.
The advantage of drawing glycans this way is that we see their exact structure.
The disadvantage of of drawing glycans this way is that it is super difficult to do when drawing freehand, it ain’t that even easy when using an app, and finally – being “exact” isn’t always an advantage! Look at that last molecule. Yes, if you look at it long enough you might figure out that it is a bunch of sugars.
But what about complex molecules like this that are made of many different types of sugars? It would be very difficult to interpret a drawing. Thus we have developed an easier way to visually represent them!
from GlyTech, Inc
How to draw glycans: the easier way
There is a standard Symbol Nomenclature for Glycans (SNFG).
It is from the National Center for Biotechnology Information, U.S. National Library of Medicine.
Super easy to read, each color and shape represents a different sugar.
On the top is an example of a glycan in which we draw the name of each sugar. Technically correct but hard to read.
So below it we show the easier way to draw and color the glycan, so we can see which sugars it is made of.
from National Center for Biotechnology Information, U.S. National Library of Medicine
Another example: Here are seven sugars (monosaccharides.)
And here they are linked together. The atom by atom details are not necessary.
from glytech-inc
Articles
Recent Advances in Nutritional Sciences: An Overview of Glycans and miRNAs, Marcello Menapace
KaiserScience 