CD Inflammatory and Immunologic Concepts

Infection

Infection

Implantation and successful replication of an organism within the body causing an immunologic response.

Communicable Disease

Illness caused by an infectious agent or its toxins

Contagious Disease

Disease that is easily transmitted

Infectious Disease

Requires direct inoculation through a break in the skin or mucous membrane

Host

The living being in which the infectious agent resides

Reservoir

Place where an infectious agent lives and multiplies

Disinfection

Destruction of pathogens outside the body by physical or chemical means.

Concurrent Disinfection

Disinfection while the patient is still the source of infection

Terminal Disinfection

Disinfection when the patient is no longer the source of infection.

Isolation

Separation of a person with a communicable disease from others.

Reverse Isolation

Separation of an immunocompromised person to protect them from communicable diseases.

Quarantine

Limitation of freedom within the longest incubation period of a disease.

Epidemiologic Triangle

A model that considers the interaction between the agent, host, and environment in disease spread

Agent– Host – Environment

Patterns of Occurrence and Distribution

Endemic– Sporadic– Epidemic– Pandemic

Endemic

A disease constantly present in a population or area

Epidemic

A sudden increase in the number of disease cases above the expected level in a certain area

Pandemic

An epidemic that has spread across multiple countries or continents, affecting a large population.

Agent

An organism or substance that causes disease, including bacteria, viruses, fungi, protozoa, prions, and helminths

Causative Agent

Reservoir

Portal of Exit

Mode of Transmission

Portal of Entry

Susceptible Host

Chain of infection

Infectivity

The ability of an agent to invade and replicate in a host

Virulence

The strength of an agent in causing severe disease

Pathogenicity

The ability of an agent to cause disease

Antigenicity

The ability of an agent to stimulate antibody production

Invasiveness

The ability of an agent to live and multiply outside the host's body.

Mode of Transmission

The means by which an infectious agent spreads from one host to another

Direct Contact

Transmission through physical contact between an infected and a susceptible person

Indirect Contact

Transmission through contact with contaminated surfaces or objects.

Droplet Spread

Transmission through respiratory droplets expelled when coughing or sneezing.

Airborne Transmission

Transmission of infectious agents through air particles that can be inhaled.

Vehicle-borne Transmission

Transmission through contaminated food, water, or objects

Vector-borne Transmission

Transmission through an intermediate organism, typically insects like mosquitoes or ticks.

Community-acquired Infection

An infection contracted outside of healthcare facilities

Nosocomial Infection

An infection acquired within a hospital or healthcare setting

Iatrogenic Infection

An infection caused by medical procedures or treatments

Incubation Period

The time between exposure to an infectious agent and the appearance of the first symptoms

Infection —> 1st SSx

Prodromal Stage

The period from the onset of early symptoms to the appearance of specific disease signs

– 1st SSx —> Pathognomonic signs

Illness or Fastigial Stage

The phase when all disease symptoms are present and most severe.

Convalescence or Defervescence

Subsiding SSx and recovery

The recovery phase when symptoms subside, and the patient returns to health

Natural Immunity

Immunity acquired through natural infection or passive transfer from mother to child

active, passive

Artificial Immunity

Immunity acquired through vaccination or administration of antibodies.

active, passive

Inactivated, Attenuated

types of antigens

Inactivated Vaccine

A vaccine containing killed pathogens, requiring multiple doses and booster shots for long-lasting protection

– Not long lasting

– Multiple doses

– Booster needed

Attenuated Vaccine

A vaccine containing weakened live pathogens that provide long-lasting immunity with a single dose.

Strict Isolation

Contact Isolation

Respiratory Isolation

Enteric Isolation

Drainage/Secretion Precaution

Universal Precaution

types of isolation

Strict Isolation

Complete separation of a person with a highly contagious disease to prevent transmission

Contact Isolation

Isolation to prevent disease spread through direct or indirect contact.

Respiratory Isolation

Isolation to prevent transmission of diseases spread through airborne droplets.

Enteric Isolation

Isolation to prevent transmission of gastrointestinal infections through fecal-oral routes

Drainage/Secretion Precaution

Precaution to prevent infection from wound drainage or body secretions.

Universal Precaution

Standard infection control practices applied to all patients, regardless of infection status

chicken pox

rubeola

rubella

scabies

The integumentary diseases

Chicken Pox (Varicella-Zoster Virus)

• MOT

  • Airborne

  • Direct Contact

  • Contact with contaminated fomites

• Incubation Period: 11 to 21 Days

• Period of Communicability – 5 days before onset of rash and 5 days after first crop of vesicles

Chicken Pox (Varicella-Zoster Virus)

• SSx

  • Itchy maculovesiculopapular lesions

  • Earliest complication: Encephalitis

  • Late complication: Herpes Zoster

Chicken Pox (Varicella-Zoster Virus)

• Dx

  • Tszank Smear

  • Lesion: Center —> Periphery

Chicken Pox (Varicella-Zoster Virus)

• MGT

  • Strict Isolation

  • Fever: NO ASPIRIN

  • Pruritus

    • Calamine Lotion

    • Oatmeal bath

    • Cornstarch bath

    • Antihistamine

    • Cut nails or use mittens

• DOC: Acyclovir/Zovirax

Rubeola (Measles)

A highly contagious viral infection marked by fever, cough, and a characteristic rash, preventable by vaccination.

• Measles, 1st Disease, English Disease, 7 day rash

• Agent: Paramyxoviridae

• MOT:

  • Airborne

  • Direct Contact

  • Indirect Contact

• Incubation Period: 7-14 days

• Period of Communicability: Just before the prodrome until 4 days after the rash appears

Rubeola (Measles)

• Pre-eruptive Stage

  • Fever

  • Catarrhal symptoms

  • Stimson’s line

• Eruptive Stage

  • Maculo-papular rash (EXANTHEM)

  • High grade fever

  • Anorexia and Irritability

• Convalesnce Stage

  • Rashes fade away

  • Fever subsides

  • Desquamation begins

  • Symptoms subsides

Koplik’s Spots

Small white lesions inside the mouth, pathognomonic for measles.

Rubeola measles

• MGT

  • Supportive and Symptomatic

    • Fever – TSB

    • Koplik Spots – Gentian violet, water and salt–

  • Vitamin A

    • <1 yr – 100,000 IU

    • >1yr – 200,000 IU

    • Pregnant – 10,000 IU

  • Dim light and use Shades

• Complication: Bronchopneumonia

• Prevention: Immunization

  • Anti-measles: 9 months

  • MMR

    • 1st dose at 15 months

    • 2nd dose at 12 years old

Rubella

• German measles, 3 Day Rash

• Togaviridae

• MOT

  • Droplet

  • Direct contact of respiratory secretions

  • Transplacental Transmission

• Incubation period: 2 to 3 day

• Prevention

  • MMR: 2 doses

  • Rubella titer <1:8 - Not immune

  • Immune serum globulin within one week after exposure

Rubella

• Prodromal Period

  • Low grade fever

  • Headache

  • Malaise

  • Mild coryz

  • Conjunctivitis

  • Cervical lymphadenopathy

• Eruptive Period

  • Forchheimer’s Spot — Pathognomonic

  • Rash – last for 1 to 5 days

  • Orchitis

  • Transient polyarthritis

Congenital Rubella

• IUGR– IUFD

• Cleft palate

• Cardiac Defects

• Eye defects

• Ear defects

• Mental retardation

Scabies (Sarcoptes scabiei)

• The Itch

• MO

  • Direct inoculation

  • Skin to skin contact

  • Indirect contact with fomites

• IP: 4 to 6 weeks

• Signs and Symptoms

  • Linear burrow

  • Anaphylactic reaction

  • Acropustulosis

    • Pustules

    • Blisters

    • Ulceration

Scabies (Sarcoptes scabiei)

• MGT

  • Kwell lotion (Gamma benzene hexachloride)

  • Crotamiton (Eurax)

  • DOC: IVERMECTIN: Single dose

• Prevention

  • Good personal hygiene

  • Avoid direct contact with infected persons

  • All members of the household should be treated

Rabies

Leprosy

Tetanus

Meningitis

Poliomyelitis

Neurologic Diseases

Rabies

• Hydrophobia, Lyssa

• Rhabdovirus

• All warm blooded animals are susceptible

• MOT

  • Bite or scratch of rabid animal

  • Transplant of infected organ

• IP: 9 days to 7 years

Rabies

• SSx

  • Numbness at site

  • Salivation

  • Fever

  • Headache

  • Malaise

  • Hydrophobia/Aerophobia

  • Hallucination

  • Confusion or Restlessness

  • Respiratory paralysis

• Dx: Flourescent Antibody Test

Rabies

• MGT

  • Wash wound for 5 minutes

  • Observe the dog for 10 to 14 days

  • Do not rub garlic on wound

  • Hospital: assess for

    • Severity

    • Site (Proximity)

    • Numbness

    • Duration

    • Give Tetanus Immunoglobulin

• Bayrab

• Verorab

• Rabipur

• Imogam

• Rabies Immunoglobulin

Leprosy

• Lepra, Hansenosis, Hansen’s Disease

• Mycobacterium leprae

• MOT

  • Droplet

  • Skin to skin contact

• 3 Distinct Forms

  • Lepromatous leprosy

  • Tuberculoid leprosy

  • Borderline leprosy

Lepromatous leprosy

• Multibacillary

• Lepromin test negative

• Large amount of bacilli in skin lesion

• 24-30 months treatment

• Rifampicin, Dapsone, Lamprene(Clofazimine)

Tuberculoid leprosy

• Paucibacillary

• Lepromin test positive

• Organism rarely isolated on skin lesion

• 6-9 months treatment

• Rifampicin, Dapsone

leprosy

Early SSx

• Change in skin color

• Loss of sensation

• Decreased/absent sweating and hair growth

• Thickened or painful nerves

• Muscle weakness or paralysis

• Nasal obstruction

• Pain or redness of eyes

• Non healing ulcer

Late SSx

• Gynecomastia

• Madarosis

• Lagopthalmos

• Leonine facies

• Contractures

• Clawing

• Sinking nose bridge

• Chronic ulceration

leprosy

Dx:

• Slit Skin Smear

Tetanus

• Lock jaw

• Clostridium tetani

• MOT:

  • Direct Inoculation

• IP:– 3 to 21 days

• SSx

  • Hemolysis — Tetanolysin

  • Spasms – Tetanospasmin

  • Opisthotonus

  • Trismus

  • Risus sardonicus

tetanus

• MGT

  • Wash wound area

  • Hospital: Antitetanus Serum (ATS)

  • Spasms

    • Dilantin

    • Diazepam

  • DOC

    • Metronidazole

    • Penicillin (GABA Antagonist)

• Prevention:

  • TT: 5 doses

  • DPT

Meningitis

• Neisseria gonorrhea

• MOT

  • Droplet

• SSx

  • Increased ICP

  • Kernig’s Sign

  • Brudzinki’s Sign

• Dx

  • Lumbar Tap

    • Cloudy

    • Yellowish

    • Decreased glucose

    • Increased protein

meningitis

• MGT

  • Respiratory Isolation

  • N95 mask

  • DOC:

    • Penicillin G

    • Mannitol

    • Steroids – cerebral edema

• Prevention

  • Avoid contact with infected person

Poliomyelitis

• Infantile paralysis, Acute flaccid paralysis (AFP)

• Agent:

  • Poliovirus 1,2,3

  • Legio Debilitans

    • Brunhilde

    • Leon

    • Lansing

• MOT

  • Feco-oral transmissionPoliomyelitis

Poliomyelitis

• SSx

  • Poker Spine — destruction of anterior horn cells of spine

  • Hoyne’s Sign

  • Tripod Sign

  • Muscle tenderness, weakness, and spasms

  • Asymmetrical Paralysis of the extremities

  • Loss of superficial and deep reflexes

Poliomyelitis

• Dx: Pandy’s Test

• MGT

  • Enteric isolation

  • ROM exercises

  • Trochanter rolls and foot board are indicated

  • Physical Therapy

• Prevention

  • SALK: Inactivated Polio Vaccine (IPV)

  • SABIN: Oral Polio Vaccine (OPV)

Dengue

Malaria

Filariasis

Vector-Borne Diseases

Dengue

• H Fever, Dandy’s Fever, Breakbone fever, Infectious Thrombocytopenic Purpura

• Agents

  • Dengue virus 1,2,3,4

  • Arbovirus

  • Chikungunya virus

• MOT

  • Vector-borne: Aedes Egypti

GRADE 1

Dengue grade?

• Dengue fever

• Fever: 39 degrees Celsius

• Abd. Pain and vomiting

• Petechial rash

Grade 2

Dengue grade?

• Dengue hemorrhagic fever

• Bleeding

Grade 3

Dengue grade?

• Circulatory collapse

Grade 4

Dengue grade?

• Shock, coma, and death

dengue

• Dx: Confirmatory

  • CBC

  • Platelet count

• MGT

  • Supportive and symptomatic

    • Fever: Analgesics, NO ASPIRIN

    • Increase fluid intake

    • Oresol

    • IVF

    • Blood transfusion

• Prevention

  • Sanitation

  • Treated mosquito nets

  • On-stream seeding

  • On-stream clearing

  • Wear covered clothing

  • Planting Neem trees

  • Zooprophylaxis

Malaria

• Marsh Fever, Ague

• Agents:

  • Plasmodium falciparum

  • Plasmodium vivax

  • Plasmodium malariae

  • Plasmoidium ovale

• MOT

  • Vector: Anopheles mosquito

  • Blood transfusion

  • Transplacental

Malaria

• SSx

  • Paroxysms with shaking chills

  • Rapid rising fever with severe headache

  • Profuse sweating

  • Myalgia

  • Splenomegaly

  • Hepatomegaly

• Dx: Malarial Smear

• MGT

  • Chemoprophylaxis: Chloroquine

  • DOC

    • Arthimeter

    • Quinine

    • Primaquine

Filariasis

• Elephantiasis

• Agent:

  • Wuchereria bancrofti

  • Brugia malayi

  • Brugia timori

• MOT:

• Vector:

  • Aedes Poecellus

  • Culex quinquefasciatus

  • Anopheles Minimus

Filariasis

• S/Sx:

  • 1. Acute-Inflammation

    • 1. Lymphadenitis

    • 2. Lympharyngitis

    • 3. Epidydimitis

  • 2. Chronic

    • 1. Lymphedema

    • 2. Hydrocele

    • 3. Elephantiasis

• Dx:

  • 1. Nocturnal Blood Smear-8PM above

  • 2. Immunochromatographic Test

  • 3. Bentonite Flocculation Test

• DOC:

  • DEC (Diethyl Carbamazipine Citrate)

  • Hetrazan/BeltrazanFilariasis

Diphteria

Pertusis

Pneumonia

Tuberculosis

Respiratory Diseases

Diphteria

• Agent:

  • Klebs-Loeffler Bacillus

  • Corynebacterium Diphteria•

• MOT:

  • Droplet

Diphteria

• S/Sx:

  • 1. Nasal – Foul smelling nasal discharge

  • 2. Pharyngeal – Pseudomembrane, bull-neck

  • 3. Laryngeal – Stridor

• Dx:

  • 1. Confirmatory: Nasal and Throat Swab

  • 2. Schick’s Test – Susceptibility

  • 3. Maloney’s Test - HypersensitivityDiphteria

• Mgt:

  • 1. Do not remove the pseudomembrane

  • 2. Anti-Diphteria Serum

  • 3. Tracheostomy set at bedside

  • 4. DOC:

    • 1. Penicillin

    • 2. Erythromycin

Pertusis

• Whooping cough

• Agent:

• Bordotella pertussis

  • Haemophilus pertussis

  • Bordet-Gengou Bacillus

• MOT:

  • Droplet

  • Direct contact of respiratory discharges

Pertusis

• Dx:

  • 1. Nasal and Throat Swab

• MGT:

  • DOC: Erythromycin

  • Supportive Therapy

    • Fluid and Electrolytes replacement

    • Adequate nutrition

    • Oxygen therapy

Catarrhal

Pertusis

• S/Sx:

  • ______ Stage - Highly communicable

    • 1. Cough

    • 2. Sneezing

    • 3. Teary eyes

    • 4. Fever

Paroxysmal

Pertusis ________ Stage - Frequent coughing ending in inspiratory whoop.

Pneumonia

• Consolidation of the lungs

• Agent: Streptococcus Pneumoniae

• MOT: Droplet

• S/Sx: Rusty Sputum

• DOC:

  • 1st Amoxicillin

  • 2nd Cotrimoxazole (Hepatotoxic)