Analyze issues of public health, infectious diseases, & bioterrorism

Analyze issues of public health, infectious diseases, & bioterrorism.

They remain the leading cause of death!

Public Health can be improved with

biomedical research!

How??

Read on….

A. Nature of infectious diseases

1. Pathogens- Microorganisms that are capable of causing disease.

2. Infection- results when a pathogen invades and begins growing within the host.

3. Disease- results only if and when tissue function is impaired (I.e. burns, skin lesions)

Guinea Worms!

4. The body has defense mechanisms to prevent infection – normal flora, physical attributes (nasal passages)

5. In order to cause a disease, pathogens must be able to enter, adhere, invade, colonize, and inflict damage.

6. Entrance to the host -- mouth, eyes, genital openings, wounds.

7. Growth of pathogens or the production of toxins/enzymes cause disease (impairment of tissue function).8. Some normal flora prevents disease

Infectious Disease Process

1. Bacteria- i.e.Salmonella typhi, Staphylococcus aureus (may lead to MRSA)

2. Viruses - apart from the host cell, have no metabolism and cannot reproduce.

3. Fungi- form spores (i.e. ringworm, athletes foot)

4. Protozoa- acquired through contaminated

food or water, or bite of an arthropod (mosquito)

*** Occurs more in tropical environment!!!! ***

5. Helminths - simple, invertebrate animals, some infectious parasites- symptoms: abdominal pain and diarrhea

6. Prions- i.e. Creutzfeldt-Jakob disease – causes holes in brain

7. Trichinella spiralis – Fatal cases due to respiratory paralysis.

1. Epidemiology- study of the occurrence of disease in populations

2. Disease reservoirs- where the infectious agent survives (humans, rodents)example= yersinia pestis3. Modes of transmission

(direct contact, airborne, etc).

1. Nonspecific mechanisms are the body’s defenses against disease- anatomical barriers, physiological deterrents and presence of normal flora (skin, low Ph and high salinity)

2. Specific mechanisms - immunity

3. Vaccination- produces immunity

What symptoms might a patient exhibit if they developed the infectious disease previously recognized prior to 1983 as being noninfectious.

Gastric ulcers caused by H-pylori (bacterium) have symptoms of abdominal pain and

indigestion.

How does biomedical research help the

population?

What is the role of public health in the prevention of infectious disease?

1. Safe water- US water is purified through settling, filtration, and chlorination

2. Sewage treatment and disposal is mandated by the federal government.

This is a public health concern!!!!After a hurricane the safety of the

water supply is often in jeopardy.

Settling Filtration Chlorination

3. Food Safety- US has many standards, inspection plans and regulations dealing food preparation, handling, and distribution. Pasteurizing milk & dating it for sale demonstrates food safety.

4. Animal control programs - Domestic herds are inspected, rabid animals are destroyed, rat control programs in place in urban areas.

i.e. Rabies primarily spread by direct contact.

5. Vaccination programs mandate that children be vaccinated prior to school. The reason vaccinations work, is a pathogen cannot reproduce itself enough to maintain disease in population.

6. Pesticides to block vectorborne disease- those carried by mosquitoes. Mosquitoe spraying kills the insect with pesticides therefore decreasing / eliminating vectorborne disease i.e. malaria

1. National Institutes of Health (NIH) - supports health-related research

2. Centers for Disease Control (CDC) - investigates disease outbreaks, publishes reports, sponsors education/research, reference labs

3. Food and Drug Administration (FDA)- monitors safety of food, medicines and other products

4. World Health Organization (WHO) - provides global surveillance and control of diseases.

FDA NIH CDC

1. New research techniques- has lead way to rapid identification.

2. HIV protease inhibitors

3. Vaccine research4. Identification of

better preventative measures.

What is the treatment for infectious diseases?

1. Penicillin’s / cephalosporin's interfere with certain layers of cell wall synthesis.

2. Chloramphenicol, tetracyclines, and erythromycins- may be toxic when used in high doses or prolonged periods of time.

3. Rifampin- used for treatment of Tuberculosis. (TB)…is considered re-emerging because of antibiotic resistance.

1. Antiviral drugs target virus - specific enzymes.

2. Acyclovir- used in treatment of genital herpes

3. Amantadine- used to prevent or moderate influenza.

4. AZT- inhibit replication of HIV genome.

1. Penicillin resistance noted as early as 1943.

2. Mycobacterium tuberculosis - some strains resistant to all drugs.

3. Resistance to antibiotics - result of changes in genetic information of bacteria.

4. Indiscriminate (random) use of antibiotics increases drug resistance.

A. Emerging infectious diseases1. Have not occurred in humans before,2. Have occurred previously but affected

only small numbers,3. Or have occurred throughout human

history, but only recently recognized as disease due to infectious agent (i.e. H. Pylori)

Once were major health problems globally or in a particular country, then declined dramatically, but are again becoming health problems for a significant proportion of the population

An infectious disease is considered to be

Re-emerging once occurred, greatly declined,

then increases in incidence.

What about bioterrorism???

1. Bacterial - Anthrax and Plague

2. Viral- Smallpox

3. Toxins - Botulism and Ricin (Saddam used it to “practice”bioterrorism in his own country)

1. Isolation practices2. Patient placement3. Patient transport - limited to movement

that is essential 4. Cleaning, disinfection and sterilization

of equipment and environment - follow standard precautions

5. Discharge management – lots of teaching before going home.

6. Post-mortem care - should you tell the funeral director what the pt died of if it is from an infectious disease? Yes to ensure it is not spread!

7. Do you know how to wash your hand?The best water temperature to use is

warm.

Terrorism is defined in the United States code, Title 18, section 2331 (18 USC

2331) as: Violent acts or acts dangerous to human life that…appear

to be intended

1. Healthcare facilities would group affected victims together in the same facility if there were a large scale bioterrorism attack.

2. If we were in a foreign country we would be kept there until we were noninfectious.

3. Victims least symptomatic will be sent home and instructed on barrier precautions, handwashing, and cleaning.

Purpose of bioterrorism…1. To intimidate or coerce a civilian

population.2. To influence the policy of a

government by intimidation or coercion; or

3. To affect the conduct of a government by assassination or kidnapping.

Biological weapons used in bioterrorism are living microorganisms such as bacteria, viruses, fungi, that can kill or incapacitate.

Funeral director would need to know the cause of death from a bioterrorist attack because special post-mortem precautions must be taken.

Health care facilities may be the initial site of recognition and response to bioterrorism activity. Because of this, the names and telephone numbers for internal and external departments or agencies that need to be contacted should be kept by each facility in its bioterrorism readiness plan.

By following standard precautions the general public could protect themselves from bioterrorism agents.

The guideline recommends wearing gloves when collecting or handling blood and body fluids contaminated with blood and wearing face shields when there is danger of blood splashing on mucous membranes and when disposing of all needles and sharp objects in puncture-resistant containers.

1. Internal reporting requirements (within a facility):a. Infection control personnelb. Epidemiologist (local and state)c. Administration (health care facility and health department)d. Office of public affairs in the health facility

a. Local health department b. State Health Departmentc. FBId. CDCe. Local policef. EMS

a. Bacterial- Anthrax and Plagueb. Viral- Small Poxc. Toxins- Botulism and Ricin

Acute infectious disease caused by bacillus anthracis.

Was sent through the mail to federal agencies in Washington D.C. in October 2001.

Infections in humans: Skin contact- cutaneous, ingestion-

gastrointestinal, inhalation-pulmonary Person-to-person transmission of inhalation

disease does not occur.**direct exposure to vesicle secretions of

cutaneous anthrax can result in a secondary infection.

Pulmonary signs and symptoms: Flu-like symptoms that may briefly

improve two to four days after initial symptoms

Abrupt onset of respiratory failure Hemodynamic collapse Thoracic edema Widened mediastinum on xray Positive blood culture in 2-3 days of

illness

Prognosis:

Good if treated early. Increased mortality rate if treated after respiratory onset.

Local skin involvement with direct contact

Commonly seen on head, forearms, or hands

Localized itching followed by popular lesion that turns vescular within 2-6 days- develops into depressed black eschar

Cutaneous signs and symptoms:

Prognosis:

Good if treated with antibiotics.

Gastrointestinal signs and symptoms:

Abdominal pain, nausea, vomiting, fever

Bloody diarrhea, hematemesis Positive culture after 2-3 days

Prognosis:

If progression to toxemia and sepsis, prognosis is poor.

Modes of transmission:

Inhalation of spores Skin contact Ingestion of contaminated food

Pulmonary: 2-60 days Cutaneous: 1-7 days Gastrointestinal: 1-7 days

Transmission:

Anthrax is not airborne, person to person.

Direct contact with infectious skin lesions can transmit infection.

Vaccine available in limited quantities.

Potent neurotoxin caused by an anaerobic bacillus-colstridium botulinum.

Transmission: Contaminated food Inhalation

Signs and symptoms: Gastrointestinal symptoms Drooping eyelids Weakened jaw clench Difficulty swallowing or speaking Blurred vision Respiratory distress

Incubation period: Neurological S/S for

food borne botulism – 12-36 hours after ingestion

Neurological S/S for inhalation botulism- 24-72 hours after exposure

Prevention: Vaccine availableBotulism cannot be

transmitted person to person

It is one of the most poisonous naturally occurring substances, and it is the most toxic protein. Though it is highly toxic, it is used in minute doses both to treat painful muscle spasms, and as a cosmetic treatment in some parts of the world. It is sold commercially under the brand names Botox, Dysport, and Myobloc for this purpose.

Plague is an acute bacterial disease caused by yersinia pestis.

There are three major manifestations Bubonic plague; Septicemic plague; Pneumonic plague; Any bubo-causing disease; A pandemic caused by such a disease; Any pestilence, a virulent and highly infectious disease

Signs and symptoms: Fever Cough Chest pain Hemoptysis Watery sputum Bronchopneumonia on xray

In 1563, London experienced another outbreak of plague, considered one of the worst incidences of plague ever seen in the city. The bubonic plague took almost 80,000 lives.

Plague normally transmitted from an infected flea.

Can be aerosol-probable use in bioterrorism.

Can be transmitted person to person.

A potent protein toxin derived from Castor beans. Castor beans are found easily all over the world & the toxin is fairly easily produced. For this reason ricin could be used as a biological weapon with relative ease.

Infections in Humans Aerosol IngestionSigns & Symptoms18-24 hours-weakness, fever, cough,

pulmonary edema36-72 hours-severe respiratory distress &

then death from hypoxemia.Incubation period8-18 hoursPrognosisPoor-no vaccine availableRicin does not spread easily person to person.

Smallpox is an acute viral illness caused by the variola virus.

Mode of transmission-Airborne, droplets

Signs/Symptoms-Flu like symptoms-fever, myalgia.

*Skin lesions appear quickly progressing from macules to papules to vesicles.

*Rash scabs over in 1-2 weeks.

*Rash occurs in all areas at once, not in crops

The "white man" diseases…measles, chicken pox, typhus, typhoid fever, dysentery, scarlet fever, diphtheria, and after 1832, cholera…were devastating to the American Indian. Lumped together, these diseases did not equal the havoc of smallpox in terms of number of deaths, realignment of tribal alliances, and subsequent changes in Canadian and American Indian Cultures.  

A virus that has a long latent period that uses an enzyme to copy itself into a host cell.

Malaria is classified as a re-emerging infectious disease because it is drug resistant and fear of vaccination.

It is a vector-borne infectious disease caused by protozoan parasites. It is widespread in tropical and subtropical regions, including parts of the Americas, Asia, and Africa.

Organisms usually found in the dirt. Is a medical condition that is

characterized by a prolonged contraction of skeletal muscle fibers.

Is a re-emerging infectious disease because people refuse to be vaccinated.

Amantadine- it prevents or shortens episodes of influenza.

In humans, common symptoms of the disease are the chills, then fever, sore throat, muscle pains, severe headache, coughing, weakness and general discomfort. In more serious cases, influenza causes pneumonia, which can be fatal, particularly in young children and the elderly.

An adult on antibiotics!

A contributing factor to the emerging disease is cooling & plumbing systems.

Is the more severe form of the infection and produces pneumonia. Any infected water source.

A severe and highly contagious type of pneumonia.

First recognized in 2003, making it a Emerging disease.