AY Honors/Biosafety/Answer Key

Biosafety

Approval authority:
Category:
Skill Level:
Year of Introduction:

Contents

1. Define the following terms:

a. Biosafety

Biosafety is defined as the discipline addressing the safe handling and containment of infectious microorganisms and hazardous biological materials; procedures intended to protect humans or animals against disease or harmful biological agents.

b. Biohazard

A biohazard is a biological substance that's dangerous to people or the environment. Many biohazards are made of bacteria or other microorganisms. Some biohazards are an unintentional side effect of biologists working with or studying toxins or viruses. One common type of biohazard is medical waste — things like used syringes or other tools contaminated with human blood, bacteria, or other microorganisms. The word biohazard was first used around 1973, from the Greek bio-, "life," and hazard, from the Old French hasard, "game of chance."

c. Risk Factor

A risk factor is something that increases a person's chances of developing a disease. For example, cigarette smoking is a risk factor for lung cancer and obesity is a risk factor for heart disease.

d. Biological material

Biological materials are natural biocompatible materials that comprise a whole or a part of a living structure or biomedical device that performs, augments, or replaces a natural function. Biological materials are most often engineered for medical, biotechnology and pharmaceutical applications.

e. Chemical or biological accident

A biological or chemical accident is the unintentional release of one or more hazardous substances which could harm human health and the environment. Chemical hazards are systems where chemical accidents could occur under certain circumstances. Such events include fires, explosions, leakages or release of toxic or hazardous materials that can cause people illness, injury, or disability. It may occur due to natural or human-made sources.

f. Chemical or biological incident

An incident is more general and accident is more specific, regarding hazardous materials. An incident can refer to any event – big or small, good or bad, intentional or unintentional. Accidents are always unintentional and they usually result in some damage or injury.

g. Pathogen

A pathogen is a bacterium, virus, or other microorganism that can cause disease. A pathogen may also be referred to as an infectious agent, or simply a germ.

h. Aerosols

Aerosols are a suspension of fine solid or liquid particles in gas. it is an abbreviation of "aero-solution." Smoke, fog, and mist are aerosols.

i. PPE

Personal protective equipment (PPE) is protective clothing, helmets, goggles, or other garments or equipment designed to protect the wearer's body from injury or infection. The hazards addressed by protective equipment include physical, electrical, heat, chemicals, biohazards, and airborne particulate matter.

2. Describe which PPEs are used by health professionals. What are they for? Discuss at least five other non-health care fields that routinely use PPE for protection from biohazards and why they are needed.

PPE used by health professionals

Gloves

Prevent the hands from coming into contact with contaminated material.

Face mask

Reduce the possibility of inhaling airborn pathogens. Also reduces the chances of an infected healthcare worker from contaminating others.

Face shield

Protects the face from being sprayed by contaminated material or bodily fluids.

Gown/Scrubs

Protects the body from coming into contact with contaminated materials.

Hazmat suit

Also called Positive Pressure Personnel Suit (PPPS). Offers maximum protection against biohazards. This equipment is typically used in research laboratories.

• 

  Glove

• 

  Caps, scrubs, goggles, and face mask

• 

  Level 4 Hazmat suit (Positive Pressure Personnel Suit)

Examples of Non-Healthcare professions that use PPE

• Wastewater (sewage) Engineer/technician/laborer
• Waste management (garbage)
• Cleaning Services
• Law Enforcement
• Fireman
• Agriculture
• Veterinary
• Manufacturing
• Coroners
• Property Management
• Food Preparation
• Slaughterhouse/Meatpacking Operations
• Laboratory
• Hazmat Operations
• Correctional Facilities

3. Differentiate between outbreak, epidemic, pandemic and endemic. Make a Venn diagram or chart that shows the things that are the same and those that are different.

• Outbreak: Refers to the number of cases (disease) that exceeds what would be expected.

• Endemic: An infection or disease that exists permanently in a particular region or population. For example, Malaria is a constant worry in parts of Africa.

• Epidemic: An outbreak of a disease that is actively spreading over a wide geographic area and affects an exceptionally high proportion of the population.

• Pandemic: A global endemic. It relates to geographic spread and is used to describe a disease that affects a whole country or the entire world.

An example of this is dengue fever. There are parts of the world where dengue fever is endemic, meaning that there are mosquitoes that are carrying dengue fever and transmitting it from person to person. But we also see imported cases and imported outbreaks in parts of the world where a disease is not endemic. There was an outbreak in the Big Island of Hawaii where somebody, unknown, must have come in with dengue fever, got bitten by mosquitoes, and then there were local chains of transmission where those mosquitoes then bit other people, they got dengue fever, and so on and so on. In this case, dengue fever is not endemic in the Big Island, however, there was an outbreak due to an imported disease with subsequent transmission.

4. Develop a list of precautions that should be taken during an epidemic/pandemic.

Frequent hand washing

The most common pathway for a pathogen to enter the body is for it to come into contact with the hands, and then be transferred to the face. Doorknobs, shopping carts, light switches, or other high-touch surfaces which are shared by many people are potential points for transference of germs to the hands. Whenever you arrive at your home (or other safe zone), it is very important to wash your hands immediately. Try to minimize the things you touch before you can wash your hands and make a mental note of which things you do touch.

You should also always wash your hands at these times:

• After you have used the bathroom
• Before you prepare food.
• Before you eat.

This guidance applies even if you are not caught in the middle of an epidemic.

Rinse your hands well. If you find that your hands are getting dry and crackly, you are probably not rinsing them well enough. Water doesn't generally cause your hands to dry out - soap does. Use a lotion if your hands dry out, and try to rinse them better next time. Don't let dry hands discourage you from washing them!

Avoid touching your face

See the discussion above on hand washing.

Disinfecting

When you arrive at your home you should have made a mental note of all the things you touched before you were able to wash your hands. Those are the surfaces should be disinfected. Clean them as soon as you finish washing your hands.

When you leave a public place and get to your vehicle, if you can use hand sanitizer before you get in your car, you can get away with not disinfecting your car when you get home. But if you forget, you need to use a disinfecting wipe to clean everything you touched in the car:

• Door handles (inside and outside)
• Steering wheel
• Gear shift
• Controls (power window buttons, A/C, heat/fan controls, cruise control, etc)
• Seat belt buckles
• Turn signal
• Radio controls
• Parking brake
• Garage door opener

In the house:

• Garage door closer
• Doorknobs
• Faucet handles
• Light switches
• Refrigerator handle
• Countertops
• Cell phone
• Purse/wallet
• Credit/debit cards

Other high-touch surfaces that should be regularly disinfected:

• Laptop keyboards
• Tablets
• Remote controls
• Reusable water bottles

Social Distancing

If the disease causing the outbreak does not have an effective treatment or vaccine, one of the only tools for slowing its spread is to keep people away from each other. This recommended separation distance depends on how the disease is spread. For COVID-19, which is spread by respiratory droplets, public health professionals recommend staying at least 6 feet (2 meters) from other people (especially strangers).

Face masks

A face mask should be worn when it is necessary to be in a public place during an epidemic which spreads by respiratory droplets. The mask will serve to reduce the amount of pathogens entering the wearer's mouth or nose, and also reduce the amount of pathogens emitted by the wearer. The latter point is especially important when the disease can be transmitted before the victim is aware of any symptoms.

Wearing a mask sends the message "I care about you, and if I am infected, I don't want to spread it to you."

When a mask is removed it should be placed in the laundry and the hands should be washed or sanitized as soon as possible.

Water Treatment/Hygiene

Some outbreaks, such as cholera, are spread through the use of water which has been contaminated by human feces. Proper sanitation prevents the cholera bacteria from getting into the water source in the first place. Water treatment kills any of the bacteria that may have been introduced into the water system. Water should be sterilized before drinking it, bathing with it, or cooking with it.

Mosquito Control

Yellow fever, malaria, West Nile, and Eastern equine encephalitis (EEE) are all spread by mosquitoes. To control the disease, you must control the mosquitoes. This is done by sleeping under mosquito netting, wearing mosquito repellent (DEET-based repellents being the most effective) emptying standing water where mosquitoes breed, and in extreme cases, through the use of pesticides.

5. Chart, list, or illustrate the differences between isolation and quarantine.

Chart - A simple T-chart can be created by folding a piece of copy paper (A3 or letter) in half "hotdog" style so that you have two long columns. On one side you write words or short phrases that describe Isolation and on the otherside you write comparable ideas that illustrate quarantine. Ex.

Isolation	Quarantine
Protect public health	Protect public health
Staying separate from others because you are sick	Staying separate from others to lower the chance of exposing/being exposed to the illness
Individuals who are sick/exposed stay away from others and use separate bathrooms etc to keep others in their family and community from getting exposed by them	Families stay away from other groups of people but share housing, bathroom, etc.

A list is more paper-pencil without a manipulative but accomplishes the same purpose as the chart.

Illustrate means using photos, drawings, sketches, or pictures collected from the internet to illustrate the similarities and differences between the two words. The "Illustrate" option is by far the MOST FUN!

Definitions and Explanations: Isolation and quarantine are public health practices used to protect the public by preventing exposure to people who have or may have a contagious disease.

Isolation

Isolation separates sick people with a contagious disease from people who are not sick. Hospitals use isolation for patients who have a known infectious disease that can be spread easily to others. Household members should use a separate bedroom and even a separate bathroom if possible. It is also recommended that the ill person should eat or be fed in their room away from other household members. Household items such as dishes, drinking glasses, cups, eating utensils, towels, bedding, or other items should not be shared with the person infected. It is important to prohibit all visitors and non-essential people from being in the home.

Quarantine

Quarantine separates and restricts the movement of people who were exposed to a contagious disease to see if they become sick. These people may have been exposed to a disease and do not know it, or they may have the disease but do not show symptoms. Quarantine helps to limit the spread of communicable disease. Quarantining means staying home and away from other people as much as possible for at least a 14-day period. This includes avoiding shopping, eating out, socializing, public places, and large crowds.

6. Choose two of the following historic diseases and answer: When did it occur? How many were infected? How was it spread? What were the symptoms? What were the biosafety precautions used? How was it abated?

• 1918 Influenza (Spanish Flu)

The 1918 influenza, originally known as the Spanish flu, occurred from January 1918 to December 1920, it infected 500 million people.

The close quarters and massive troop movements during World War I hastened the pandemic, and probably both increased transmission and augmented mutation. Some speculate the soldiers' immune systems were weakened by undernourishment, as well as the stresses of combat and chemical attacks, increasing their susceptibility. A large factor in the worldwide occurrence of this flu was increased travel. Modern transportation systems made it easier for soldiers, sailors, and civilian travelers to spread the disease.

The sick experienced such typical flu symptoms as chills, fever and fatigue.

When the flu hit, doctors and scientists were unsure what caused it or how to treat it. Unlike today, there were no effective vaccines or antivirals, drugs that treat the flu. Officials in some communities imposed quarantines, ordered citizens to wear masks and shut down public places, including schools, churches and theaters. People were advised to avoid shaking hands and to stay indoors, libraries put a halt on lending books and regulations were passed banning spitting. According to The New York Times, during the pandemic, Boy Scouts in New York City approached people they’d seen spitting on the street and gave them cards that read: “You are in violation of the Sanitary Code.”

However, a second, highly contagious wave of influenza appeared with a vengeance in the fall of that same year. Victims died within hours or days of developing symptoms, their skin turning blue and their lungs filling with fluid that caused them to suffocate. In just one year, 1918, the average life expectancy in America plummeted by a dozen years.

After the lethal second wave struck in late 1918, new cases dropped abruptly – almost to nothing after the peak in the second wave. One explanation for the rapid decline in the lethality of the disease is that doctors became more effective in prevention and treatment of the pneumonia that developed after the victims had contracted the virus. Another theory holds that the virus mutated extremely rapidly to a less lethal strain. This is a common occurrence with influenza viruses: there is a tendency for pathogenic viruses to become less lethal with time, as the hosts of more dangerous strains tend to die out.

• Polio

Polio is a viral disease caused by the poliovirus. According to the Smithsonian National Museum of American History, the first outbreak of polio in epidemic form in the U.S. occured in 1894 in Vermont, with 132 cases. The World Health Organization estimates 350,000 cases were infected with polio.

Polio is spread when the stool of an infected person is introduced into the mouth of another person through contaminated water or food (fecal-oral transmission). Oral-oral transmission by way of an infected person's saliva may account for some cases.

Nonparalytic polio
Some people who develop symptoms from the poliovirus contract a type of polio that doesn't lead to paralysis (abortive polio). This usually causes the same mild, flu-like signs and symptoms typical of other viral illnesses.

Signs and symptoms, which can last up to 10 days, include:

• Fever
• Sore throat
• Headache
• Vomiting
• Fatigue
• Back pain or stiffness
• Neck pain or stiffness
• Pain or stiffness in the arms or legs
• Muscle weakness or tenderness

Paralytic polio
This most serious form of the disease is rare. Initial signs and symptoms of paralytic polio, such as fever and headache, often mimic those of nonparalytic polio. Within a week, however, other signs and symptoms appear, including:

• Loss of reflexes
• Severe muscle aches or weakness
• Loose and floppy limbs (flaccid paralysis)

Post-polio syndrome
Post-polio syndrome is a cluster of disabling signs and symptoms that affect some people years after having polio. Common signs and symptoms include:

• Progressive muscle or joint weakness and pain
• Fatigue
• Muscle wasting (atrophy)
• Breathing or swallowing problems
• Sleep-related breathing disorders, such as sleep apnea
• Decreased tolerance of cold temperatures

The poliovirus has been eradicated in the United States since 1979, thanks to the use of effective vaccines. Other steps to prevent the spread of polio include washing hands with soap and water after using the bathroom and changing diapers, and before preparing food and eating. If soap and water are not available, an alcohol-based hand rub can be used.

• Swine Flu

The Swine Flu, also known as H1N1, began in January 2009. From April 12, 2009 to April 10, 2010, the CDC estimated there were 60.8 million cases (range: 43.3-89.3 million), 274,304 hospitalizations (range: 195,086-402,719), and 12,469 deaths (range: 8868-18,306) in the United States due to the virus.

Spread of the 2009 H1N1 virus is thought to occur in the same way that seasonal flu spreads. Flu viruses are spread mainly from person to person through coughing, sneezing or talking by people with influenza. Sometimes people may become infected by touching something – such as a surface or object – with flu viruses on it and then touching their mouth or nose.

The signs and symptoms of swine flu are similar to those of infections caused by other flu strains and can include:

• Fever (but not always)
• Chills
• Cough
• Sore throat
• Runny or stuffy nose
• Watery, red eyes
• Body aches
• Headache

The best way to prevent swine flu is to get a yearly flu vaccination. Other easy ways to prevent swine flu include: frequently washing hands with soap or hand sanitizer. not touching your nose, mouth, or eyes (The virus can survive on surfaces like telephones and tabletops.)

The United States mounted a complex, multi-faceted and long-term response to the pandemic, summarized in The 2009 H1N1 Pandemic: Summary Highlights, April 2009-April 2010. On August 10, 2010, WHO declared an end to the global 2009 H1N1 influenza pandemic. However, (H1N1)pdm09 virus continues to circulate as a seasonal flu virus, and cause illness, hospitalization, and deaths worldwide every year.

7. Choose two of the following diseases and answer: What are the symptoms? How is it spread? Is there a cure today? Where and when was there an outbreak/epidemic/pandemic? Is there a prevention for this disease? What are the biohazard safety methods used to combat the spread of this disease?

• Ebola

What are the symptoms? The symptoms appear usually 8-10 days after virus exposure, but as early as 2 days and as late as 21 days after exposure. symptoms usually start with “dry” symptoms initially (such as fever, aches and pains, and fatigue), and then progress to “wet” symptoms (such as diarrhea and vomiting) as the person becomes sicker.

Usually people with Ebola show several of the following symptoms: Fever; Aches and pains, including headache, body aches, and stomach aches; Weakness and fatigue; diarrhea and vomiting; stomach pain; Unexplained hemorrhaging, bleeding or bruising

How is it spread? It is spread from infected fruit bats and monkeys to people. People spread it through bodily fluids. It can only be transmitted from people who are demonstrating symptoms of EVD (Ebola). There are not known "asymptomatic" contaminations known.

Is there a cure today? There is no cure / antiviral medication as of 2020. Symptoms are treated,in hopes that the person's immune system can fight off the virus.

Where and when was there an outbreak/epidemic/pandemic? The largest outbreak of Ebola (as of 2020) was in West Africa (Zaire strain) with over 28,600 cases. The Democratic Republic of the Congo has an ongoing case that began in late 2019 and is ravaging that country as of the writing of this answer key.

Is there a prevention for this disease? There is a vaccine for the Zaire Ebola virus. It was approved in 2019. What are the biohazard safety methods used to combat the spread of this disease? eliminating contact with bodily fluids of infected persons or contact with tools/tables/clothing/bedding etc. that the bodily fluids have contacted. Thus PPE usage of gloves, gowns, sterilization and etc are all used by clinicians.

• AIDS

Symptoms

There are several symptoms of AIDS. Not everyone will have the same symptoms. It depends on the person and what stage of the disease they are in.

Below are the three stages of HIV and some of the symptoms people may experience.

Stage 1: Acute HIV Infection Within 2 to 4 weeks after infection with HIV, about two-thirds of people will have a flu-like illness. This is the body’s natural response to HIV infection.

Flu-like symptoms can include:

• Fever
• Chills
• Rash
• Night sweats
• Muscle aches
• Sore throat
• Fatigue
• Swollen lymph nodes
• Mouth ulcers

These symptoms can last anywhere from a few days to several weeks. But some people do not have any symptoms at all during this early stage of HIV.

Stage 2: Clinical Latency In this stage, the virus still multiplies, but at very low levels. People in this stage may not feel sick or have any symptoms. This stage is also called chronic HIV infection.

Without HIV treatment, people can stay in this stage for 10 or 15 years, but some move through this stage faster.

Stage 3: AIDS If HIV is present and the person is not on HIV treatment, eventually the virus will weaken the body’s immune system and will progress to AIDS (acquired immunodeficiency syndrome). This is the late stage of HIV infection.

Symptoms of AIDS can include:

• Rapid weight loss
• Recurring fever or profuse night sweats
• Extreme and unexplained tiredness
• Prolonged swelling of the lymph glands in the armpits, groin, or neck
• Diarrhea that lasts for more than a week
• Sores of the mouth, anus, or genitals
• Pneumonia
• Red, brown, pink, or purplish blotches on or under the skin or inside the mouth, nose, or eyelids
• Memory loss, depression, and other neurologic disorders

Each of these symptoms can also be related to other illnesses. The only way to know for sure if a person has HIV is to get tested.

Many of the severe symptoms and illnesses of HIV disease come from the opportunistic infections that occur because the body’s immune system has been damaged.

Transmission

You can only get HIV by coming into direct contact with certain body fluids from a person with HIV who has a detectable viral load. These fluids are:

• Blood
• Semen and pre-seminal fluid
• Rectal fluids
• Vaginal fluids
• Breast milk

For transmission to occur, the HIV in these fluids must get into the bloodstream of an HIV-negative person through a mucous membrane (found in the rectum, vagina, mouth, or tip of the penis); open cuts or sores; or by direct injection.

HIV is NOT spread by:

• Air or water
• Mosquitoes, ticks or other insects
• Saliva, tears, or sweat that is not mixed with the blood of a person with HIV
• Shaking hands; hugging; sharing toilets; sharing dishes, silverware, or drinking glasses; or engaging in closed-mouth or “social” kissing with a person with HIV
• Drinking fountains

HIV can’t be passed through healthy, unbroken skin.

Cure

At this time, there is no cure for AIDS, but medications are effective in fighting HIV and its complications. Treatments are designed to reduce HIV in your body, keep the immune system as healthy as possible and decrease the complications that may develop.

8. Complete the following:

a. Which of the previous diseases studied are or were endemic to your local area?

Many areas in the USA and other countries can cite statistics of the pandemic spread of COVID-19 of 2019-2020. It would be interesting however to see which others were prevalent in your area! For example, Ebola was and is prevalent on the African continent.

9. How do vaccines work? Why is it important to be up to date with your immunizations?

A vaccine is medicine given by a doctor or nurse and makes a person less likely to get a disease. It gives immunity to an infectious disease caused by a particular germ (bacteria or virus). For example, the flu vaccine makes it less likely that a person will get the flu. A flu vaccine is often called a flu shot.

Vaccines are usually made from something that is alive, or was alive.

The word "vaccine" comes from the Latin words vaccīn-us (from the word vacca, meaning "cow"). In 1796, Edward Jenner used cows infected with cowpox (variolae vaccinae) to protect people against smallpox.[1] The use of vaccines is called vaccination. Simple English Wikipedia: Vaccines Vaccines work because they train the person's body to "learn how to fight off" the full-strength disease. There are two major types of vaccines. "live vaccines" and "inactivated vaccines."

It is important to be up to date with immunizations because most vaccines don't last forever but need "boosted." Thus, if a person misses part of an ongoing schedule of vaccines, they may lose their immunity or partial immunity to the virus or bacteria that the vaccine was protecting them from.

10. Name a national or global entity that assists in developing and applying disease prevention and control.

a. Where is this organization located?

CDC

In the United States the CDC (Centers for Disease Control) is headquartered in Atlanta, Georgia, United States.

WHO

The WHO (World Health Organization), an international health agency, is located in Geneva Switzerland.

PHAC

The Public Health Agency of Canada (PHAC) is headquartered in Ottawa, Ontario. It is responsible for public health, emergency preparedness and response, and infectious and chronic disease control and prevention in Canada.

b. What information does it relay and why is it important to know how to access that information?

Both the CDC and the WHO work to collect data from regional, state, national, and global sources and data points (NNDSS)to track any diseases or situations that affect or could effect public health. Information for both organizations is available on their websites US Center for Disease Control: CDC and World Health Organization: WHO

11. Explain why it is so important to remove medical gloves properly. Demonstrate the proper way to remove medical gloves without transferring pathogens from the gloves to your hands through the following exercise:

The skin is your body’s largest organ. It protects your organs and acts as a barrier that guards against micro-organisms and chemicals; but as protective as skin is, it needs protection, too. That’s because while skin is working hard to keep contaminants out, some actually absorb through unless you’re wearing PPE. Then there’s the risk of cross contamination or carrying a contaminant elsewhere. Even if you were wearing gloves while working with the contaminant, if you remove disposable gloves incorrectly, it can deposit the very same hazard back onto the skin that you thought you’d protected.

12. Regarding the cleaning of hands:

a. Why is hand washing recommended rather than hand sanitizing whenever possible?

Hand washing reduces the amounts of all types of germs and chemicals on hands. But if soap and water are not available, using a hand sanitizer with at least 60% alcohol can help you avoid getting sick and spreading germs to others.

Hand sanitizers may not be as effective when hands are visibly dirty or greasy. When hands are heavily soiled or greasy, hand sanitizers may not work well. Hand washing with soap and water is recommended in such circumstances.

Hand sanitizers also might not remove harmful chemicals, like pesticides and heavy metals, from hands. Although few studies have been conducted, hand sanitizers probably cannot remove or inactivate many types of harmful chemicals. In one study, people who reported using hand sanitizer to clean hands had increased levels of pesticides in their bodies.

b. What steps should be taken to make sure all parts of the hands are clean? Explain why it is important to follow each step.

The World Health Organization recommends the technique shown in this video. It is effective because it methodically cleans all of the skin on the hands - palms, backs of hands, between fingers, finger tips, and thumbs. Germs can hide on any of those surfaces, and this technique takes that into account.

c. What song have you found that is long enough that you can sing it completely while scrubbing your hands?

Singing the Pathfinder Song at a good regular tempo can easily take up to 30 seconds!

d. Why is the use of paper towels preferable over cloth towels that will be used several times?

It's possible to leave germs behind on what ever you use to dry your hands (especially if you don't do a great job of washing them). Since paper towels are used once and thrown away, they are unlikely to infect anyone. Cloth towels should be reserved for situations where people do not share towels.

e. Make a video or other presentation to demonstrate to your instructor how to properly wash and dry your hands.

You can watch the video from the WHO (see above), but you need to make your own presentation. It could be a video, poster, live demonstration, or some other presentation that your instructor approves.

13. Regarding hand sanitizer:

a. Why is 70% isopropyl alcohol the most effective concentration as the main cleansing sanitizer ingredient?

70% alcohol takes a longer time to evaporate from any surface, hence there is enough contact time. In the case of 100% alcohol, evaporation will be very fast, contact time will be less and it will not be so effective against microbes.

70 % isopropyl alcohol solution kills microorganisms by dissolving the plasma membrane of the cell wall. Plasma membrane of gram negative bacteria consist of thin layer of peptidoglycon that is easily destroyed by the alcohol.

Water plays key important role which used to denature the proteins of cell membrane and acts as a catalyst in the reaction. Contact time of the alcohol with the organism also plays an important role. A 70% solution of alcohol takes more time in evaporation from the surface, increasing the contact time. Therefore, 70% isopropyl alcohol fulfills the both requirements.

The 100% isopropyl alcohol coagulates the proteins instantly by creating a protein layer that protects the other proteins from further coagulation. Because of this, microbes are not killed but remain in a dormant stage.

b. What is the correct way to use hand sanitizer?

Apply about a teaspoon (5 ml) of hand sanitizer to your hands. Rub it in thoroughly, being sure to get the palms, the backs of the hands, between the fingers, and the finger tips. Do not wipe the hands dry, but rather, allow the sanitizer to evaporate. This leaves the sanitizer in contact with any germs long enough for it to disinfect the hands.

c. Explain when it is appropriate to use hand sanitizer instead of soap and water.

Hand sanitizer can be used when soap and water are not readily available. Using soap and water is always the more effective way to wash your hands.

14. Regarding face masks:

b. Learn how to improvise a face mask using materials commonly found around your home.

YouTube video with U.S. Surgeon General demonstrating a technique:

18. According to 1 Corinthians 15:51-58 and Revelation 21:1-5, what will happen to sicknesses and diseases when we go to Heaven?

Template:Division variant