Chapter 14 Lecture

bacteria & viruses

Preventing and Controlling Infectious Diseases


The Increasing Threat of Infectious Diseases

• The significant advances in antibiotics and vaccines to fight infectious diseases during the 20th century lulled many health officials and the public into thinking that the primary diseases of the 21st century would be chronic diseases caused primarily by lifestyle choices
• The emergence and reemergence of many infectious disease agents have been fueled by the following

    • unprecedented worldwide population growth -increased international travel
    • increased transport of animals and food products
    • changes in food processing and handling
    • human encroachment on wilderness habitats
    • microbial evolution with resistance to antibiotics and other antimicrobial drugs

Primary Burden of STI's

Transmitted Infections

• Sexually transmitted infections (STIs) can be physically and emotionally devastating for women
• The stigma attached to many STIs can cause women to deny the possibility of having a STI, leading to a delay of testing and treatment
• Women need to become knowledgeable about the most common STIs and infectious diseases by asking questions and seeking information
• A woman should know the risks associated with STIs and practice assertive skills to prevent illness and unprotected sex

Common Bacterial Sexually Transmitted Infections

• Chlamydia
• Most common bacterial sexually transmitted infection in the United States
• Reported rates are higher than men, suggesting that many male partners are not screened
• The bacterium Chlamydia trachomatis causes the symptoms via sexual intercourse
• Symptoms include

    • Vaginal discharge
    • Burning urination
    • Lower abdominal pain
    • Bleeding between menstruation
    • Fever
    • Nausea

• Gonorrhea
• Caused by the Neisseria gonorrhea bacterium
• Infection often is asymptomatic until complications such as PID occurs
• Symptoms include

    • Thick yellow or white vaginal discharge
    • Burning during urination
    • Severe menstrual or abdominal cramps

• The incidence of gonorrhea continues to decline and the CDC reports rates of 106.5 per 100,000 persons annually
• Left untreated, can lead to arthritis, dermatitis, and tenosynovitis
• Syphilis
• Caused by the spirochete, Treponema pallidum
• Primarily passed via sexual intercourse
• Consists of four phases

    • Primary: painless brown or red sores
    • Secondary: rash on the palm of hands/sole on feet
    • Latent: no symptoms
    • Tertiary: destructive lesions and damage to the CNS

• Syphilis has been linked to increased susceptibility to HIV
• Condoms are a good source of protection but only protects the covered areas

• Chancroid
• Caused by the bacterium H. ducreyi
• Characterized by a painful genital ulceration
• Most prevalent in Africa and the Caribbean
• Risk factor for HIV transmission
• Difficult to culture or to test

Common Viral Sexually Transmitted Infections

• Herpes Simplex Virus (HSV)
• Spreads from direct skin to skin contact
• Can affect oral (Type 1) and genital areas (Type 2)
• Either can manifest on any side of the body
• Symptoms include

    • Itching, burning, and swelling
    • Small painful blisters appear in the genitalia (type 2)
    • Common viral symptoms such as fever, headaches, muscular aches, and chills

• There is no cure for Herpes Simplex but medications can reduce the severity of breakouts

• Human Papilloma Virus (HPV)
• Related to the formation of cervical cancer
• Known as genital warts which grow on or around reproductive organs
• Spread by direct skin contact
• There is no cure for HPV but lesions can be removed with proper treatment
• Most HPV infections are transmitted by sexual activity and diagnosed by an abnormal Pap smear

Reproductive Tract Infections

• Vaginitis

    • Nearly 10% of women who visit their health care provider complain of vaginal discharge
    • Types of Vaginitis

• Bacterial vaginosis (BV): non-specific vaginitis
• Trichomoniasis: one cell parasite that causes vaginal irritation
• Candidiasis: yeast infection, not usually sexually transmitted

Inflammatory Disorders

• Pelvic Inflammatory Disease

    • PID is an infection of the upper portion of the female reproductive tract beyond the cervix
    • Common symptoms include

• Severe pelvic pain
• High fever
• Chills
• Nausea
• Vomiting

    • PID is diagnosed through a pelvic exam or by analysis of vaginal or cervical secretions
    • Treatment includes antibiotics, rest, and sexual abstinence
    • PID is the only cause of infertility that is preventable

• Cervicitis

    • Inflammation of the cervix

HIV / AIDS

• HIV (Human Immunodeficiency Virus) is the retrovirus that causes Acquired Immune Deficiency Syndrome (AIDS)
• Transmitted from person to person through blood, semen, or vaginal secretions
• Symptoms of AIDS may be similar to those of other diseases, but they take longer to disappear and may reappear

    • Recurring fever
    • “Night Sweats”
    • Rapid weight loss without diet or exercise
    • Diarrhea lasting longer than several weeks
    • White spots in the mouth
    • Dry cough and shortness or breath

• In the United States, women represent 24% of all HIV diagnoses with women of color disproportionately represented
• These women are faced with an array of psychosocial, economic, cultural, and relational issues
• In 2008, HIV/AIDS was the third leading cause of death for African American women aged 35-44 years
• The most common methods for heterosexual women to contract AIDS are through contact with bisexual or heterosexual men followed by injecting drug use

Diagnosis of HIV

• Serologic and virologic testing
• Elisa test
• Western Blot test
• Oraquick test
• Home HIV tests
• Home Access Express

Treatment of HIV

• Drug treatment focuses on reducing the viral load or reinforcing the immune system by:
• Blocking HIV attachment to the CDR cell
• Blocking antigens on the virus envelope
• Interfering with the uncoating of the virus as it enters the cell
• Blocking RNA to DNA
• Disrupting the assembly of needed particles to form HIV
STIS In Women Who Have Sex With Women (WSW)
• Exposure of a mucous membrane to vaginal secretions and menstrual blood is potentially infectious
• Condoms, dental dams, or plastic wrap can help during oral sex
• Condoms should be used correctly when using sex toys
• Bacteria in the rectum can cause infections in the vagina and urethra
• Contact with a towel, underwear, bed linens, etc. can transmit some STIs from an infected woman
• Self contact after touching a partner’s genitals can transmit some STIs
• Some STIs can be transmitted from vulva to vulva contact
• A woman’s own and her partner’s HIV status can increase the risk of infection

Prevention Strategies

• Preexposure Vaccination
• Abstinence
• Monogamy
• Engaging in less risky behaviors with partners
• Oral contraceptives
• Male condoms
• Female condoms

Other Infectious Diseases

• Epstein-Barr Virus (EBV)
• Influenza (flu)
• Hepatitis A
• Hepatitis B
• Hepatitis C
• Tuberculosis (TB)
• MRSA
• Streptococcal Disease
• Varicella (Chickenpox and Shingles)
• Encephalitis
• Lyme Disease