DEN 111 Test 3 Study Material (Part 2)

Forms/Modes of Transmission of a Pathogenic Organism

• direct contact

• droplet spread

• indirect/vehicle contact

• aerosols

• vector-borne

Direct Contact

physical contact (kissing, sex, touching)

Indirect/Vehicle Contact

contact with contaminated items/surfaces (needle, objects)

Droplet Spread

direct contact with respiratory droplets (cough, sneeze, speaking)

Airborne/Aerosols

small particles suspended in the air for long periods of time after the infected individual leaves the room/area

Vector-Borne

insects/animals (mosquitoes, ticks)

Seroconversion

the process of converting from a “negative” to a “positive” blood test

Window Phase

period of time between exposure and the positive blood test (seroconversion)

Incubation Period

time from exposure to an infectious agent until signs and symptoms of the disease appear

(time that passes between seroconversion and the appearance of symptoms )

Incubation period of HBV

up to 200 days

Incubation period of HIV

up to 10 years

What is yellowing associated with?

accumulation of bilirubin in skin

HIV

human immunodeficiency virus

AIDS

acquired immunodeficiency syndrome

What cells do HIV invade and how does it affect the body?

CD4/T helper cells, makes it hard for body to fight off infection

What are CD4/T-helper cells?

white blood cells that play a major role in the immune system (they are attacked by HIV)

What type of virus is HIV?

• RNA virus

• Retro virus

• (genetic information is stored in the form of RNA instead of DNA)

Is HIV an acute or latent virus?

both acute and latent

HIV-2

• causes slower progression of disease

• uncommon in US

• same mode of transmission as HIV-1

HIV-1

• first recognized in homosexual population in the US

What makes up greatest number of HIV cases?

• unprotected sex

• IV drug users

What type of HIV is responsible for AIDS in America, Europe and Asia?

HIV-1

What does disease status depend on?

• dose

• virulence

• host susceptibility

Immunodeficiency

immune systems ability to fight infectious disease is compromised or entirely absent

Immunity

• natural or acquired resistance to a specific disease

• can be partial or complete

• can be long lasting or temporary

Immunocompetent

• healthy

• capable of developing a immune response

• possessing a normal immune system

How is HIV transmitted?

• blood products (unclean needles, unscreened blood)

• sharing needles to inject drugs

• mother to baby (pregnancy, birth, breastfeeding)

Is HIV spread by air/water?

no

Is HIV spread by insects?

no

Is HIV spread saliva, tears, or sweat?

no, unless it is contaminated with blood

Does HIV spread by casual contact or closed mouth kissing?

no

Can HIV reproduce outside of the body?

no it can’t reproduce outside of the body

What is one of the most common opportunistic infections among people with HIV/AIDS?

tuberculosis

PreP

• pre-exposure prophylaxis

• when people at very high risk for HIV take HIV medicines daily to lower their chances of getting infected

PEP

• post exposure prophylaxis

• only used in emergencies

• should be started within 72 hours of possible exposure for 28 days (4 weeks)

• taking antiretroviral medicines after potentially being exposed to HIV to prevent becoming infected

How long should PEP be received?

4 weeks

Is PEP 100% effective?

no it is not 100% effective

PEP testing

must be paid for by employer

ARS

• acute retroviral syndrome

• incubation period 1-6 weeks

• self-limiting without treatment

After acute infection HIV is considered what?

chronic

ARC

• aids related complex

• symptomatic HIV infection (patient may seek treatment because they wonder why they can’t get over the “flu”)

• prodromal phase of infection

Thrush

oral candidiasis

• common symptom of immune disorder

• common in those with HIV

Generalized Lymphadenopathy

persistent swollen glands under the arms, groin area, or submandibular area (otherwise asymptomatic)

CD4 level that results in AIDS

CD4 levels below 200 cells per cubic milliliter of blood

Normal Range of CD4 cells

500-1600 cells mm3

When is viral load the highest?

acute retroviral syndrome (ARS) during the AIDS stage

Symptoms of full blown AIDS

• persistant fevers

• severe fatigue

• rashes

• significant weight loss

• pneumonia

Kaposi’s Sarcoma

• cancer that develops from the cells that line lymph or blood vessels

• considered an AIDS defining illness (if you have HIV and this appears you officially have AIDS)

Hairy Leukoplakia

• white raised lesions having keratin projections on surface

• appears on tongue/buccal mucosa of those with HIV/AIDS

CDC Estimated survival rate

average of three years once AIDS has been diagnosed

Cure

treatment can stop without the risk of infection resurfacing

Appearance of positive reaction to a TB skin test

swelling at injection site

What is the number one reason dormant TB becomes active?

HIV

Can someone be TB positive but not contagious?

yes if they have latent TB

Bloodborne pathogens we are concerned with in dentistry

• Hep B

• Hep C

• HIV

What cells does HIV invade?

CD4/T helper cells

(makes it hard for the body to fight off infection)