Course 138 Workplace Hygiene and Illness Prevention

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Contagious Diseases

What are Pathogens?

Pathogens are organisms that cause infectious diseases. Pathogens are also known as infectious agents and germs. When a pathogen enters and attacks a host, symptoms begin to appear. A host is a human who can carry a pathogen and become ill.

There are five main types of pathogens. In the workplace, viruses and bacteria are the most common causes of illness. Viruses are infectious agents that require a living host to replicate and thrive. Viruses cause viral infections. Bacteria are microscopic, single-celled organisms that supports many forms of life. Most bacteria are harmless, but there are a few that can cause illness. Bacteria cause bacterial infections.

Examples of infectious diseases caused by pathogens:

  • Common Cold: Many viruses can cause the common cold. It is a viral infection that affects the nose and throat.
  • Influenza (flu): A contagious respiratory illness caused by influenza viruses. It affects the nose, throat, and sometimes the lungs.
  • Coronavirus Disease 2019 (COVID-19): COVID-19 is a disease caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus. This virus is related to the coronavirus responsible for the SARS outbreak of 2003. Cases have ranged from mild symptoms to severe respiratory illness and death.
  • Norovirus: The norovirus is also known as the stomach flu. Norovirus is a common virus that is not related to the flu.
  • Measles: A highly contagious, serious disease that is caused by a virus. About 1 in 5 (20%) unvaccinated people in the U.S. who get measles are hospitalized.
  • Strep Throat: A mild bacterial infection that affects the throat and tonsils.
  • E. coli: Escherichia coli (E. coli) are bacteria found in the environment, food, and intestines of people and animals. Most strains of E. coli are harmless, but others can make you sick.

1. What is true about pathogens?

a. Pathogens are microorganisms that support all forms of life
b. Pathogens are the cause of infectious diseases
c. Pathogens do not cause disease
d. There are four types of pathogens

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Communicable vs. Non-Communicable Diseases

Communicable diseases are transmissible diseases caused by pathogens. Most communicable diseases are spread through contact with contaminated surfaces and infected hosts. Communicable diseases are transmitted through direct or indirect transmission.

Non-communicable diseases are long-term illness caused by a combination of factors. These factors can include genetics, environment, and behaviors. Non-communicable diseases describe conditions that remain for one year or more. Non-communicable diseases are also known as chronic diseases. Common non-communicable diseases include heart disease, lung cancer, and diabetes.

2. Which of the following describes a communicable disease?

a. Communicable diseases include heart disease, lung cancer, and diabetes
b. Communicable diseases are caused by a combination of factors
c. Communicable diseases are long-term
d. Communicable diseases are transmissible diseases caused by pathogens

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Modes of Transmission

illness transmission methods
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Most people work outside their homes. This increases the risk of exposure to pathogens that cause infectious diseases. Pathogens can be transmitted through direct or indirect transmission. Direct transmission can occur through direct contact or droplet spread. Indirect contact occurs when pathogens are transferred through airborne transmission, vehicles, or vectors.

Direct Transmission

  • Direct Contact: Direct contact refers to contact with surfaces that contain pathogens. Direct contact includes person-to-person contact. For example, a worker who has coughed into their hand can directly transfer pathogens by shaking hands with their coworkers.
  • Droplet Spread: Droplets from a cough, sneeze, or talking can spread an infectious disease. This type of transmission requires people to be within close proximity. For example, droplets from sneezing can spray over a few feet and fall on a person who is not infected.

Indirect Transmission

  • Airborne Transmission: This type of transmission occurs when pathogens are carried by dust or droplet nuclei that are suspended in the air. This can cause pathogens to remain in the air for longer periods of time and travel longer distances than droplets. For example, if an ill person coughs, the pathogens from their cough can remain suspended in the air if they fall onto dust or droplet nuclei.
  • Vehicles: A vehicle is an object or material that can carry pathogens. Common vehicles are water, food, and blood. Pathogens can infect a person when they touch or ingest a vehicle. For example, a person may contract the stomach flu if they consume food that was not handled with care.
  • Vectors: A vector is any insect or animal capable of transmitting pathogens known to cause disease in humans. Mosquitoes, fleas, and ticks are examples of vectors.

In the case of workplace hygiene, the most common modes of transmission are through direct contact, droplet spread, and airborne transmission.

3. Which of the following describes airborne transmission?

a. An object or material that can carry pathogens
b. Mosquitoes carrying the West Nile Virus
c. Pathogens are carried by dust or droplet nuclei that are suspended in the air
d. Touching surfaces that contain pathogens

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Illness symptoms
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Symptoms are indications of a disorder or illness. Each infectious disease has their own specific signs and symptoms. There are general signs and symptoms common to many types of infectious diseases.

Common signs and symptoms of infectious diseases include:

  • fever
  • sore throat
  • fatigue
  • body ache
  • coughing
  • diarrhea

Common infectious diseases and their symptoms:

  • Common Cold: Runny nose, sore throat, sneezing, coughing, headaches, and body aches.
  • Influenza (flu): Fever, cough, sore throat, runny or stuffy nose, muscle or body aches, headaches, fatigue, vomiting, and diarrhea.
  • Coronavirus 2019 (COVID-19): Fever, headache, fatigue/weakness, runny/stuffy nose, sneezing, itchy/watery eyes, diarrhea, general aches/pains, sore throat, dry cough, and shortness of breath.
  • Strep Throat: Sore throat, pain when swallowing, fever, red and swollen tonsils, and swollen lymph nodes in the front of the neck.
  • E. coli: Severe stomach cramps, diarrhea, vomiting, and fever.
  • Salmonella: Diarrhea, vomiting, nausea, stomach pain, fever, headache, and body aches.

Note: Do not use online information to self-diagnose.

When to See a Doctor

Seek medical attention if you:

  • have trouble breathing
  • have been coughing for more than a week
  • have a severe headache with fever
  • have an unexplained or prolonged fever
  • have sudden vision problems

4. Which of the following is a common symptom of infectious diseases?

a. Fever
b. Vision Problems
c. Numbness
d. Migraine

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Do you know the symptoms of Coronavirus (COVID-19)?

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Catching an infectious disease may be unavoidable, but there exist many strategies to treat diseases once they have developed. As stated previously, the most common infectious diseases contracted in the workplace are caused by viruses and bacteria. Most individuals who catch an infectious disease can recover after getting plenty of fluids and rest. In some cases, individuals may require further treatment to recover or reduce pain. Antivirals and antibiotics are used to treat infectious diseases caused by viruses and bacteria, respectively.

  • Antivirals: Antivirals are a class of medication used to treat viral infections. Antivirals stop viruses from reproducing or strengthen the body’s immune response to the virus. For example, oseltamivir, better known as Tamiflu, is an antiviral medication used to treat influenza.
  • Antibiotics: Antibiotics are powerful medicines that fight bacterial infections. Antibiotics do not work on viral infections. Antibiotics either kill or stop bacteria from reproducing. This allows the body to eliminate the pathogens. For example, amoxicillin is an antibiotic commonly used to treat strep throat.

Note: Antivirals and antibiotics are prescribed by healthcare providers.

5. What class of medicine is used to treat viral infections?

a. Amoxicillin
b. Antivirals
c. Tamiflu
d. Antibiotics

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