Infectious Diseases

1
Infectious Diseases

• Chapter 12
• Medical Considerations

2
Contraction, Transmission, and Stages of Disease

• Transmission of Infectious Disease
• Interaction of Host, Infectious Agent, and
  Environment
• Reservoirs
• Direct vs. Indirect Transmission
• Routes of Exposure
• Bloodborne, airborne, sexual, fecal-oral, and
  foodborne
• Risk of Infection
• Theoretical vs. measurable

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Contraction, Transmission, and Stages of Disease

• Factors Affecting Disease Transmission
• Mode of Entry
• Virulence
• Number of Organisms Transmitted
• Host Resistance
• Other Host Factors

4
Contraction, Transmission, and Stages of Disease

• Phases of the Infectious Process
• Latent Period
• Communicable Period
• Incubation Period
• Seroconversion and the window phase
• Disease Period

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The Bodys Defenses against Disease

• Barriers to Entry
• Intact Skin
• Respiratory System
• The Immune System
• The Reticuloendothelial System (RES)
• Identifies Foreign Material
• Includes antigens of most bacteria and viruses.
• An inflammatory response triggers mechanisms
  designed to remove foreign material.

Cellsalive.com
Viral antigens
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The Bodys Defenses against Disease

• The Immune System (cont.)
• Leukocytes
• Neutrophils and macrophages
• Cell-Mediated Immunity
• Humoral Immunity
• Results in the formation of antibodies.
• Memory and specificity.
• Antibodies (Immunoglobulins)
• IgG, IgM, IgA, IgD, and IgE
• Autoimmunity

• neutrophil, ingesting Streptococcus pyogenes

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The Bodys Defenses against Disease

• The Complement System
• The Bodys Rapid Response System
• Proteins that work with antibody formation and
  inflammatory reaction to fight infection.
• Recognizes endotoxins of certain bacteria.
• The Lymphatic System
• Structures
• Spleen, thymus, lymph nodes, and ducts.
• Collects and filters lymph.
• Facilitates Phagocytosis in Lymph Nodes.

8
Infection Control in Prehospital Care
Brady Paramedic Care Principles Practice
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Infection Control

• Recovery
• Wash your hands immediately after patient
  contact.
• If you sustain a wound and are exposed to the
  body fluids of others, wash the wound with soap
  and water immediately.
• Dispose of biohazardous wastes in accordance with
  local laws and regulations.

10
Infection Control

• Recovery (cont.)
• Place potentially infectious wastes in leak proof
  biohazard bags. Bag and label soiled linen.
• Decontaminate contaminated clothing and reusable
  equipment.
• Handle uniforms in accordance with agency policy.

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Infectious Diseases of Immediate Concern

• Human Immunodeficiency Virus
• Pathogenesis
• Risk to the General Public
• Found in blood, blood products, and body fluids.
• Common methods of transmission include sexual
  contact and shared needles.
• Risk to Health Care Workers
• Transmission to health care workers is actually
  rare.
• Accidental needlesticks are the most common
  source.
• High-risk exposures are those involving a large
  volume of blood, deep percutaneous injury, actual
  intramuscular injection, or a high
  antibody-retrovirus titer in the source

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Diseases of Immediate Concern

• HIV (cont.)
• Clinical Presentation
• Fatigue, fever, sore throat, lymphadenopathy,
  splenomegaly, rash, and diarrhea.
• Kaposis sarcoma.
• Secondary (opportunistic) infections and weight
  loss.
• Dementia, psychosis, and peripheral neurological
  disorders develop as AIDS progresses.

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Diseases of Immediate Concern to EMS Providers

• Hepatitis
• General Signs Symptoms
• Symptoms are similar regardless of type of
  infection.
• Headache, fever, weakness, joint pain, anorexia,
  nausea, vomiting, and URQ abdominal pain.
• Jaundice, clay-colored stool, and dark urine
  develop as the disease progresses.
• Hepatitis A (Infectious or Viral Hepatitis) (HVA)
• Transmitted by fecal-oral route.
• Typically is mild many patients are
  asymptomatic.
• Rarely serious and lasts 26 weeks.

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Diseases of Immediate Concern to EMS Providers

• Hepatitis (cont.)
• Hepatitis B (Serum Hepatitis) (HBV)
• Virus is transmitted through direct contact with
  infected blood, semen, vaginal fluids, or saliva.
• Risk is significantly higher for EMS providers.
• 5-35 of all needlesticks result in infection.
• Vaccination is available and recommended for all
  EMS workers.
• 6080 of infected individuals are asymptomatic.

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Diseases of Immediate Concern to EMS Providers

• Hepatitis (cont.)
• Hepatitis C (HCV)
• Primarily transmitted by IV drug abuse and sexual
  contact.
• Chronic infection that can cause active disease
  years later.
• May cause cirrhosis and end-stage liver disease.
• Hepatitis D (HDV)
• Exists only concurrently with HBV.
• Hepatitis E (HEV)
• Is similar to HAV but primarily associated with
  contaminated drinking water.

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Diseases of Immediate Concern to EMS Providers

• Tuberculosis
• General Info
• Most common preventable infectious disease
• Drug-resistant TB
• Skin Testing
• Pathogenesis
• Clinical Presentation
• Chills, fever, fatigue, chronic cough, weight
  loss
• Night sweats
• Hemoptysis

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Diseases of Immediate Concern to EMS Providers

• Tuberculosis (cont.)
• EMS Response
• Index of suspicion
• N95 and HEPA respirators
• Postexposure Identification and Management

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Diseases of Immediate Concern to EMS Providers

• Pneumonia
• General
• Differentiating pneumonia from CHF
• Source pathogens
• At-risk patient populations
• History and Assessment
• Community-acquired pneumonia.
• Signs include acute onset of chills, fever,
  dyspnea, pleuritic chest pain, cough,
  adventitious breath sounds.
• In geriatric patients, the primary sign may be an
  altered mental state.

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Diseases of Immediate Concern to EMS Providers

• Pneumonia
• Patient Management and PPE
• Management should support oxygenation and
  ventilation.
• Consider the possibility of TB.
• Consider placing a mask on yourself or the
  patient.
• Immunization and Postexposure Management
• Routine vaccination is not necessary.
• Antimicrobial agents and multidrug-resistant
  strains.

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Diseases of Immediate Concern to EMS Providers

• Chickenpox
• Varicella Zoster Virus (VCV)
• Clinical Presentation
• Respiratory symptoms, malaise, and low-grade
  fever followed by a rash.
• Rash may be the first sign of illness and may be
  limited or widespread often prolific on the
  trunk.
• Transmission is through airborne droplets and
  direct contact with lesions.
• Can be lethal in adult immunocompromised patients.

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Diseases of Immediate Concern to EMS Providers

• Chickenpox (cont.)
• Assessing Immunity
• Past history of chickenpox is sufficient.
• Immunization
• EMS Response and Postexposure
• Observe universal (standard) precautions.
• Get postexposure vaccination.

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Diseases of Immediate Concern to EMS Providers

• Meningitis
• Inflammation of the Meninges
• Caused by a variety of pathogens.
• Transmission Factors
• Host resistance factors, weather
• Contact with oral secretions
• Crowding, close contact, smoking

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Diseases of Immediate Concern to EMS Providers

• Meningitis (cont.)
• Clinical Presentation
• Incubation period of 410 days
• Fever, chills, headache, nuchal rigidity,
  arthralgia, lethargy, malaise, altered mental
  status, vomiting, and seizures
• Brudzinskis and Kernigs signs
• Immunization
• EMS Response and Postexposure
• Observe universal (standard) precautions.
• Perform postexposure prophylaxis within 24 hours.

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Other Airborne Diseases

• Influenza and the Common Cold
• Viral Infection
• Mutation and virulence
• Epidemics
• Symptoms
• Fever, chills, malaise, muscle aches, nasal
  discharge, mild cough
• Secondary infections
• Management
• Immunization

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Other Airborne Diseases

• Measles
• Viral Infection
• Highly communicable, with lifelong immunity after
  disease.
• Transmitted by airborne droplets and direct
  contact.
• Symptoms
• Presents similar to severe cold with fever,
  conjunctivitis, photophobia, cough, and
  congestion.
• Rash.
• Management
• Immunization

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Other Airborne Diseases

• Mumps
• Viral Infection
• Transmitted by airborne droplets and direct
  contact with saliva of infected patient.
• Occurs primarily in 5- to 15-year-old patients.
• Symptoms
• Painful enlargement of salivary glands
• Symptoms of cold with earache, difficulty
  chewing, and swallowing
• Management
• Immunization

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Other Airborne Diseases

• Rubella
• Systemic Viral Infection
• Symptoms
• Sore throat, low-grade fever, and fine pink rash
• Management and Immunization
• Respiratory Syncytial Virus (RSV)
• Viral Infection
• Common cause of pneumonias and bronchiolitis
• Commonly associated with lower respiratory
  infections during the winter

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Other Airborne Diseases

• RSV (cont.)
• Symptoms
• Runny nose and congestion, followed by wheezing,
  tachypnea, and signs of respiratory distress
• Management
• Pertussis (Whooping Cough)
• Bacterial Infection
• Symptoms
• Catarrhal, paroxysmal, and convalescent phases
• Management and Immunization