Pathogens and the Oral CavityWilkins CH 4

Concorde Career College

Preclinical Sciences DH101

Lisa Mayo, RDH, BSDH

Virginia Carrillo, RDH, BSDH

Pathogens Transmissible by the Oral CavityWilkins CH4

Tuberculosis p.44-45

Viral hepatitis p.45-50

HIV p.54-58

Herpetic infections p.50-54

Tuberculosis

Tuberculosis: special consideration when sterilization and disinfection methods are selected and administered

Types of TB: drug-resistant, multidrug resistant TB, extensively drug-resistant

Transmission: Inhalation of fresh droplets containing tubercle bacilli disseminated from sputum & saliva of infected individual by coughing, sneezing, or breathing heavily

Factors affecting transmission Degree to which infected individual produces infectious

droplets & amount and duration of exposure and susceptibility of the recipient

Maximum communicability is just before the disease is diagnosed

Tuberculosis

Areas of infection: lungs (most common), lymph nodes, meninges, kidneys, bone, skin, & oral cavity.

Clinical management: official CDC recommendations 1.Annual risk assessment2.Screening of all newly employed DHCP3.Taking and updating medical history 4.Referral of patients with suggestive TB history or symptoms5.Deferral of elective dental treatment6.Urgent dental care be provided in a facility that can offer isolation7.A separate reception area for suspected or confirmed TB patients

is preferred, and appointment scheduling should be arranged to prevent a waiting period.

(Source: McInnes ME. Essentials of communicable disease. 2nd ed. St. Louis: The C.V. Mosby Co.; 1975).

Review

Tuberculosis infection occurs most commonly in which area?

A) Lymph nodes

B) Lungs

C) Kidneys

D) Liver

Answer

B) Lungs is the correct answer.

Tuberculosis infection occurs most commonly in the lungs, although it can occur in lymph nodes, kidneys, bone, skin, & the oral cavity.

Viral Hepatitis

Inflammation of the liver Causes

Viral & bacterial infections Toxins & certain medications Heavy alcohol use

Viral Hepatitis

Categories A & E: Oral-fecal route. Unsanitary food & water B, C, & D: Blood-borne route. Impacts DH F & G: New, transfusion-transmitted

HEPATITIS B

Hepatitis B HBV is a serious, endemic, worldwide disease Use of strict sterilization of equipment & materials, aseptic

techniques, & self-protection measures is mandatory Transmission (cont’d next slide)

• Blood & other body fluids

• Percutaneous (intravenous, intramuscular, & subcutaneous) & Perimucosal exposure

• Accidents with needle stick & other sharps

• Exchanging contaminated needles, syringes, & other IV drug paraphernalia

1.) Sexual exposure

2.) Infection from blood transfusion & blood products

Hepatitis B

Transmission (cont’d) Perinatal transmission• During fetal stage, at birth

• Infected infant at high risk for chronic infection, which can lead to chronic liver disease or cancer later in life

Carrier state or chronic hepatitis B• All HBsAg-positive persons are potentially infective

• chronic carrier is defined as individual with the HBsAg marker found in the blood on @ least 2 occasions at least 6mo apart

Hepatitis B

Prevention: critical occupational hazard for DH due to close association with potentially infected body fluids of patients. Preventive measures Prenatal testing of all pregnant women for HBsAg Universal immunization of infants & children; immunization of

adolescents & adults (especially those at high risk) Enforce blood bank control measures (screening of donors,

strict testing for all donated blood) Enforce use of disposable syringes & needles Education of public

Active immunization: the vaccines, available since 1982 for pre-exposure & post exposure prophylaxis; stimulate antibodies & convey immunity.

Hepatitis C

General facts: Serologic test for antibody to HCV was developed in 1991, and routine blood screening was implemented in 1992.

Transmission: primarily parenteral; rarely occurs from mucous membrane exposures to blood No documentation of transmission from intact or non-intact

skin exposures to blood Sexual contact with infected partner most common

Prevention & control: No vaccine is available for HCV Education & behavior modification are essential Standards precautions in dental office

Hepatitis D

Delta hepatitis virus, also called the delta agent, causes infection ONLY in the presence of HBV infection (B BEFORE D)

Transmission Delta infection is superimposed on HBsAg carriers Multiple exposures to HBV, especially those with hemophilia

and IV drug use Transmission similar to that of HBV, by direct exposure to

contaminated blood and serous body fluids, contaminated needles and syringes, sexual contacts, and perinatal transfer

Prevention: all measures used to prevent HBV prevent HDV since delta is dependent on presence of HBV.

Immunization with HBV vaccine also protects the recipient from delta hepatitis infection (NBQ)

(Source: Hoofnagle JH. Type D hepatitis and the hepatitis delta virus. In: Thomas HC, Jones EA, editors. Recent advances in hepatology. Edinburgh: Churchill Livingstone; 1986).

Diagram shows the delta antigen surrounded by HBsAg.

Herpes1. Description

2. HSV1 & 2: Primary Herpetic Gingivostomatitis, Herpes Labialis, Herpetic Whitlow, Ocular/Opthalmic Herpes, Genital herpes

3. HSV3: Varicella-Zoster Virus

4. HSV4: Epstein-Barr Virus

5. HSV5 Cytomegalovirus

6. HSV8 Kaposi’s Sarcoma

Herpes Virus Diseases Description

Endemic worldwide, each virus causing many disease entities that are highly infectious

Public health problem due to lack of effective therapeutics & vaccines 8 strains are known to infect humans Herpes viruses produce diseases with latent, recurrent, and sometimes

malignant tendencies HS type 2 has been implicated in cervical cancer HS type 1 in oral cancer, & Epstein-Barr virus with various types of

cancer After infection, the virus has the ability to remain latent in the

individual and only become reactivated to produce recurrent infection • Certain stimuli • Immune response lowered/altered

Herpes Virus Description

Relation to periodontal disease Human herpes viruses occur in periodontitis, found in

pocket flora with relatively high prevalence Infection with herpes viruses can suppress a patient’s

immunity, and as a result, subgingival overgrowth of opportunistic periodontal pathogens can occur, making periodontal disease symptoms more severe

Herpes Virus Description

HSV-1: primary infection usually occurs in children, but may occur at any age

Antibodies (anti-HSV) are produced, but do not guarantee immunity to recurrent herpes or other herpes virus infections

Sulcular epithelium can serve as reservoir for the viruses, Anti-HSV is present in gingival sulcus fluid The possibility exists that trauma to oral tissues during

dental or DH appointment may bring about herpetic recurrence

Herpes Virus DiseasesPrimary Herpetic Gingivostomatitis

Primary infection with HSV-1 Full-blown case presents with widespread oral ulcers that may

involve pharyngeal areas Fever, malaise, inability to eat, swollen lymph nodes Reactivation may also lead to herpetic ulcerations of the lip,

the typical “cold sore”

Herpes Virus Diseases: Labialis

Herpes labialis (cold sore, fever blister) HSV-1 & HSV-2 cause genital & oral-facial infections (cannot

distinguish between the 2) Reactivation of oral-facial HSV-1 infections are more frequent than

oral-facial HSV-2 Recurrent triggers: stress, sunlight, illness, trauma (dental appts) Prodromal: prior lesion appearance, burning, stinging, tingling

sensations with slight swelling may appear Clinical characteristics

Group of vesicles form and eventually ruptures & may coalesces Crusting follows and healing may take up to 10 days The lesions are infectious, with viral shedding Care must be taken by the patient because autoinfection (to eye,

nose, or genitals) is possible, as is infection of other people Laser dentistry

Herpes Virus Diseases Labialis

Clinical management: Use patient-friendly terms such as “cold sore” or “fever blister” or “ulcer” NEVER SAY HERPES LESION!!

POSTPONE appointment for patient with active lesion Explain problems: contagiousness, may spread around

their oral cavity Irritation to the lesion(s) can prolong the course and

increase severity of the infection Prodromal state MOST contagious!!

Latent infection of herpes simplex virus. Path of the virus traced from point of viral penetration on lip to establishment of latent infection in the trigeminal ganglion

Herpes Virus Diseases: Whitlow

Herpetic whitlow HSV-1 infection of the fingers that results from viral entry

through minor skin abrasions Most frequently found around a fingernail Prevention is with use of protective gloves during dental

procedures Extinct in dentistry with standard precautions

Herpes Virus Diseases Ocular/Ophthalmic Herpes

Can be primary or recurrent infection in the eye from HSV-1 or HSV-2

Transmission from splashing saliva or fluid from a vesicular lesion directly into an UNPROTECTED eye

Prevention: PPE

Herpes Virus Diseases HSV2

Herpes simplex virus type 2 (HSV-2) Commonly known as genital herpes, but can also

occur as an oral and ocular infections Antiviral therapy can suppress HSV-2 lesions, but

the latency of the virus can never be eradicated

Herpes Virus HSV3 Varicella-Zoster Virus

Varicella-zoster virus 1. Chicken pox caused by varicella virus: highly

contagious, may be transmitted by direct contact, droplet (possibly air-borne), or indirect contact with articles soiled by discharge from vesicles and the respiratory tract.

2. Shingles caused by herpes zoster virus: chickenpox leaves lasting immunity, but the VZV remains latent in the dorsal root ganglia. Secondary infection.

Herpes Virus HSV4: Epstein-Barr Virus

EBV virus causes:

1. Infectious mononucleosis• Prevention: minimize contact with saliva by frequent

handwashing, avoiding drinking from a common container, follow standard precautions

2. Oral hairy leukoplakia• High incidence in HIV/AIDS patients

• Tongue lesions appear as white linear lesions along the lateral borders

Infectious Mononucleosis

Oral Hairy Leukoplakia

Herpes Virus HSV5 Cytomegalovirus

Cytomegalovirus (CMV) Common in HIV/AIDS Most severe form developing in infants affected in utero Transmission

• Virus from mother’s primary or recurrent infection may affect infant in utero, in the birth canal, or through breast milk.

• CMV in the fetus can lead to premature birth, anemia, mental retardation, microcephaly, motor disabilities, deafness, and chronic liver disease

• Blood transfusion, post-transplant infection, sexual, respiratory droplet (daycare rate high)

Prevention• Standard precautions, handwashing

HSV8

Kaposi’s sarcoma-related herpes virus in immunocompromised host, a major cofactor in production of Kaposi sarcoma, an AIDS-defining lesion.

HIV

HIV-1 Infection

• General facts• Severe pandemic disease caused by HIV infection • First recognized in 1981 as cluster of diseases characterized by loss

of cellular immunity • Major types: HIV-1 (more prevalent in U.S. & Europe) & HIV-2 Slow,

progressive, & often lethal• Can persist within cells such as macrophages for long periods

Transmission: semen, vaginal secretions, breast milk, blood Serological tests: 1985 (EIA/ELISA)

Confirmation with Western blot or IFA test T-helper cell % marker for progression

Review

The majority of cases of transmission of HIV in adults is due to which of the following?

A) Blood transfusion

B) Needle sharing

C) Sexual contact

D) Contact with saliva

Answer

C) Sexual contact is the correct answer.

Sexual contact is the most common way HIV is transmitted among adults. Transmission via blood transfusions is rare, especially in developed countries. Needle sharing is a method of transmission, but not as common. No cases of transmission via saliva are known.

Clinical Course of HIV-1

Seroconversion = when antibody can be detected 6wks-6mo after exposure

Incubation period: Range from time infection → AIDS symptoms Could be 15+yrs

Clinical Course of HIV-1

Early symptomatic HIV disease

CD4+ T lymphocytes 200-500 cells; continued increase in viremia; systemic symptoms: night sweats, weight loss, diarrhea, fever, malaise, general weakness; opportunistic infections begin; oral lesions become more common

Late-stage disease: AIDS

CD4+ count below 200; pneumonia is presenting feature with other AIDS-defining diseases; presentation of full-blown AIDS is highly variable & affected by host’s prior exposure to chronic infections & treatment.

Symptoms: AIDS-indicating conditions

CD4+ numbers decline, Opportunistic infections become more frequent, extensive, & severe

• AIDS-dementia complex, Tuberculosis infection, Constitutional disease, Neoplasms

• Death in 1 to 3 years (if untreated)

Oral Manifestations of HIV-1

Extraoral examination: Lymphadenopathy, Skin lesions

Intraoral examination

Fungal infections: Candidiasis

Viral infections: Kaposi Sarcoma, Herpes, Oral Hairy Leukoplakia, Chickenpox, Verrucca vulgaris, HPV, Cytomegalovirus

Bacterial infections: Linear Gingival Erythema, NUG/NUP

Dental hygiene management: Refer symptomatic patients, help maintain quality of life, educated on home care

Prevention of HIV Infection

Community education Attitudinal, behavioral changes: increase awareness, modes of

transmission, prevention methods Goals

Primary prevention: lower rate at which new cases of HIV-1 appear. HIV testing is required for all pregnant women, all newborns

Secondary prevention: For seropositive individuals to reduce the rate of transmission and introduce treatment early.

Early intervention may postpone severe clinical manifestations of advanced illness. Counsel HIV-infected individuals to practice safe sex, cooperate with screening programs, and counsel their sexual contacts and families

Postpone visit due to herpes infection Don’t touch/scratch lesion Avoid transferring virus to objects Keeping medical history up-to-date Maintaining oral health

Factors to Teach the Patient