Communicable Disease Control Prepared by Suhail Al Hu moud

Communicable Disease Control Prepared by Suhail Al Humoud Communicable Disease Control

Communicable Disease Control: Objective Prepared by Suhail Al Humoud Upon mastery of this chapter, you should be able to: ● Discuss the global and national trends and issues in communicable disease control. ● Describe the three modes of transmission for communicable diseases. ● Explain the strategies used for the three levels of prevention in communicable disease control. ● Explain the significance of immunization as a communicable disease control measure. ● Describe major issues that affect the control and elimination of tuberculosis.

Communicable Disease Control: Objective Prepared by Suhail Al Humoud ● Differentiate between human immunodeficiency virus (HIV) infection and acquired immunodeficiency syndrome (AIDS). ● Discuss specific ways to prevent sexually transmitted diseases, including HIV/AIDS. ● Identify six globally emerging communicable diseases. ● Discuss the consequences of biologic terrorism with weapons such as anthrax and smallpox. ● Describe the nurse’s role in communicable disease control. ● Discuss ethical issues affecting communicable disease and infection control

Communicable Disease Control: Introduction Prepared by Suhail Al Humoud • What is the communicable disease • A communicable disease is one that can be transmitted from one person to another. • It is caused by an agent that is infectious (capable of producing infection) and is transmitted from a source, or reservoir, to a susceptible host. • A communicable disease: A disease or illness in a susceptible host, caused by a potentially harmful infectious organism or its toxic byproduct. • Communicable disease spreads due to contact between an infectious agent and a susceptible host

Communicable Disease Control: Introduction • What is the communicable disease ……… cont • Host: a person or other living being that can be infected by an organism • Infectious agent: an organism that causes infectious disease. Agents can be: • Bactria • Fungi • Viruses • Metazoa • Protozoa • Agent: something that must be present in the environment for a disease to occur in a susceptible host

Communicable Disease Control: Introduction • What is the communicable disease ……… cont • Endemic: when an infectious agent or disease has a constant presence within a defined geographic area • Epidemic: occurrences of infectious agent or disease that clearly exceed the usual expected frequency of the disease in a particular population • Pandemic when an epidemic outbreak occurs worldwide

Communicable Disease Control: Introduction • Knowledge of communicable diseases is fundamental to • the practice of community health nursing because: • these diseases typically spread through communities of people. • Understanding of the basic concepts of communicable disease control, as well as the numerous issues arising in this area, helps a community health nurse work effectively to prevent and control communicable disease in populations and groups. • It also helps nurses teach important and effective preventive measures to community members, advocate for those affected, and protect the well-being of uninfected persons (including the nurses themselves).

Communicable Disease Control: Introduction Several issues and circumstances have emerged during the last quarter-century that are important areas of concern to community health nurses:

Communicable Disease Control: Introduction • Despite significant declines in mortality, communicable • diseases are responsible for persistently high morbidity • among various age and population groups. • • Rates of some communicable diseases, especially tuberculosis (TB) and sexually transmitted diseases (STDs), remain disproportionately high in selected population groups (in some cases, shockingly high), a fact often masked when statistics are aggregated. • • Diseases that were once little-known in the United States, such as West Nile virus, are making an appearance.

Communicable Disease Control: Introduction • The development of resistant (MDR) strains of bacteria • and viruses poses a significant occupational health challenge as well as a practice issue for health workers. • • Current research reveals that infectious agents may be responsible for a number of the chronic diseases, including • some forms of cancer, that have occupied the interest of • health care providers in the last few decades

Communicable Disease Control: Introduction • Evolution of Communicable Disease Control • Communicable diseases have challenged health care providers for centuries. • They have led to the development of countless nursing and medical preventive measures, from simple procedures such as hand-washing, sanitation, and proper ventilation to the research and development of vaccines and antibiotics. • Communicable diseases, particularly those of epidemic and pandemic proportions, such as TB and acquired immunodeficiency syndrome (AIDS), continue to cost millions of lives and billions of dollars to the global human society every year.

Communicable Disease Control: Introduction • Global Trends • During the last several decades, substantial progress has been made in controlling some major infectious diseases around the world, although other diseases have not been managed as well. The following are some of the major accomplishments: • 1995, more than 80% of the world’s children had been immunized against diphtheria, tetanus, whooping cough, poliomyelitis, measles, and TB, compared with fewer than 5% in 1974 • Global eradication of smallpox was achieved in 1980 • Because of improved sanitation and hygiene, outbreaks of • relapsing fever, transmitted by lice, are rare today.

Communicable Disease Control: Introduction • Reported cases worldwide of poliomyelitis have declined by 99% since the campaign began, with only 537 new cases in the world in 2001. • Malaria remains a major threat, even though the mortality rate has improved in the last 25 years. In 1954, there were 2.5 million deaths annually and 250 million cases of malaria worldwide; in 2002, there were an estimated 1.5 to 2.7 million deaths and 300 to 500 million cases.

Communicable Disease Control: Introduction New, Emerging, and Resurging Diseases Pathogens that are considered to be under control because they respond well to current treatment can mutate and produce new, virulent strains; diseases that have been almost eliminated can emerge again if public health efforts slacken; and diseases that are eradicated in the United States can revisit this country on any one of the hundreds of international flights arriving each day.

Communicable Disease Control: Introduction Emerging diseases are diseases rarely or never before seen one country. These diseases may also be new to public health officials in other countries. Emerging diseases occurring in the United States include the hantavirus, seen in the southwestern United States in 1993; dengue fever, acquired from travel outside the United States and first seen among people in Texas in the 1980s; and typhoid, seen in a native Nigerian in New York City in 1994.

Communicable Disease Control: Introduction Resurging diseases are those communicable diseases that have been endemic in some parts of the world but are now endemic in more countries and are increasing to epidemic proportions in others. Often, the resurgence is caused by the emergence of new, drug-resistant strains of a familiar organism, such as the MDR TB bacillus. Staphylococcus aureus infections have some strains so powerful that they are not responding to vancomycin any longer; they still respond to two new antibiotics, but those could also lose effectiveness.

Communicable Disease Control: Introduction Healthy People: Many objectives still focus on infectious diseases and immunizations, aiming to decrease morbidity and mortality from infectious diseases and to increase the number of children and adults immunized.

Communicable Disease Control: Introduction Modes of Transmission the reservoir of infection can be a person, animal, insect, or inanimate material in which the infectious agent lives and multiplies and which serves as a source of infection to others. Transmission of a communicable disease can occur by direct or indirect methods..

Communicable Disease Control: Direct Transmission Direct transmission occurs by immediate transfer of infectious agents from a reservoir to a new host. It requires direct contact with the source, through touching, biting, kissing, or sexual intercourse, or by the direct projection of droplet spray onto the conjunctiva or onto the mucous membranes of the eye, nose, or mouth during sneezing, coughing, spitting, laughing, singing, or talking. Direct transmission is limited to a distance of 1 meter or less.

Communicable Disease Control: Introduction Indirect Transmission Indirect transmission occurs when the infectious agent is transported within contaminated inanimate materials such as air, water, or food. It is also commonly referred to as vehicleborne transmission.

Communicable Disease Control: Introduction Airborne Transmission Airborne transmission occurs through droplet nuclei—the small residues that result from evaporation of fluid from droplets emitted by an infected host. They may also be created purposely by atomizing devices or accidentally in microbiology laboratories. Because of their small size and weight, they can remain suspended in the air for long periods before they are inhaled into the respiratory system of a host. Airborne transmission can also occur in dust. Small particles of dust from soil containing fungus spores may cling to clothing, bedding, or floors. Alternatively, the spores may become separated from dry soil by the wind and then be inhaled by the host..

Communicable Disease Control: Introduction PRIMARY PREVENTION In the context of communicable disease control, two approaches are useful in achieving primary prevention: (1) education using mass media and targeting health messages to aggregates (2) immunization.

Communicable Disease Control: Introduction Education Health education in primary prevention is directed both at helping at-risk individuals understand their risk status and at promoting behaviors that decrease exposure or susceptibility.

Communicable Disease Control: Introduction Use of Mass Media for Health Education All people need to be informed about the risks of communicable diseases. Often, use of the mass media is the most effective way to reach the largest number of people. Additionally, many target groups, such as low-income and racially and ethnically diverse communities at high risk for communicable diseases, are very hard to reach one on one. One way to reach them is through the media. To disseminate public health information to large numbers of people, there are four major roles of mass media:

Communicable Disease Control: Use the media as a primary change agent 1. Programs can successfully increase knowledge about communicable diseases and preventive measures. 2. Use the media as a complement to other disease prevention efforts; the media can effectively model preventive behaviors, such as condom use and drug abstinence. 3. Use the media as a promoter of communicable disease control programs; the media can help to increase participation of community members in primary prevention services. 4. Use the media to promote disease prevention messages; the media can contribute to the creation of a social environment that promotes health (eg, increasing acceptance of regular condom use in the prevention of STDs).

Communicable Disease Control: Introduction Immunization Immunization is the process of introducing some form of disease-causing organism into a person’s system to cause the development of antibodies that will resist that disease. A vaccine is a preparation made from killed, living attenuated, or living fully virulent organisms that is administered to produce or artificially increase immunity to a particular disease. Before the introduction of pertussis vaccine in the 1940s, more than 200,000 cases were diagnosed yearly in the United States, with 5000 to 10,000 deaths each year. Today, pertussis (whooping cough) claims 10 to 15 lives per year.

Communicable Disease Control: Introduction Passive immunity is short-term resistance to a specific disease- causing organism; it may be acquired naturally (as with newborns through maternal antibody transfer) or artificially through inoculation with a vaccine that gives temporary resistance. Such immunizations must be repeated periodically to sustain immunity levels. An example is the influenza vaccination. Active immunity is long-term (sometimes lifelong) resistance to a specific disease-causing organism; it also can be acquired naturally or artificially. Naturally acquired active immunity occurs when a person contracts a disease and develops long-lasting antibodies that provide immunity against future exposure

Communicable Disease Control: Introduction Vaccine-Preventable Diseases Vaccine-preventable diseases (VPD), such as hepatitis B, H. influenzae type b, measles, polio, diphtheria, pertussis, and chickenpox, are diseases that can be prevented through immunization. Immunity may be either passive or active.

Communicable Disease Control: Introduction • Herd Immunity • Herd immunity is central to understanding immunization as a means of protecting community health. it is the immunity level present in a particular population of people . • If there are few immune persons within a community, there is low herd immunity and the spread of disease is more likely. Vaccination of more individuals in the community, so that a high proportion have acquired • resistance to the infectious agent, contributes to high • herd immunity. High herd immunity reduces the probability • that the few unimmunized persons will come in contact with • one another, making spread of the disease less likely.

Communicable Disease Control: Introduction • Barriers to Immunization Coverage • Religious Barriers. • Financial Barriers • Social Barriers • Cultural Barriers • Philosophical Objections • Provider Limitations

Communicable Disease Control: Introduction • SECONDARY PREVENTION • There are two approaches to secondary prevention of communicable disease: • screening • contact investigation, partner notification, and case-finding

Communicable Disease Control: Introduction Screening The term screening is used in community health and disease prevention to describe programs that deliver a testing mechanism to detect disease in groups of asymptomatic, apparently healthy individuals.

Communicable Disease Control: Introduction Criteria for Screening Tests Validity and Reliability. The screening test must be valid and reliable. Validity refers to the test’s ability to accurately identify those with the disease. Reliability refers to the test’s ability to give consistent results when administered on different occasions by different technicians. Predictive Value and Yield. The predictive value of a screening test is important for determining whether the screening intervention is justified. Yield refers to the number of positive results found per number tested. The predictive value and the yield of screening tests become important in planning screening programs for communicable disease detection and prevention because they can help planners locate screening efforts in areas or within population groups that are known to be at high risk for the disease. The predictive value of screening tests increases as the prevalence of the disease increases.

Communicable Disease Control: Introduction Epidemiologic criteria for screening interventions for the detection of health problems are as follows: 1. Is the disease an important public health problem? 2. Is there a valid and reliable test? 3. Is there an effective and tolerable treatment that favorably influences the early stages of the disease? 4. Are facilities for diagnosis and treatment after a positive screening result available and accessible? 5. Is there a recognizable early asymptomatic or latent stage in the disease? 6. Do clear guidelines for referral and treatment exist? 7. Is the total cost of the screening justifiable compared with the costs of treating the disease if left undiscovered? 8. Is the screening test itself acceptable? 9. Will screening be ongoing?

Communicable Disease Control: Introduction Contact Investigation, Partner Notification, and Case-Finding In this approach, the community health nurse seeks to discover and notify those who have had contact with a person diagnosed with a communicable disease such as with TB and to notify partners in the case of STDs. The objective of contact investigation and partner notification is specifically to reach contacts of the index case (diagnosed person) before the contacts, in turn, become infectious (CDC, 2002c). Therefore, the rapidity with which contact investigation can be accomplished is a concern.

Communicable Disease Control: Introduction Tertiary Prevention The approaches to tertiary prevention of communicable disease include isolation and quarantine of the infected person and safe handling and control of infectious wastes.

Communicable Disease Control: Introduction Isolation and Quarantine Communicable disease control includes two methods for keeping infected persons and noninfected persons apart to prevent the spread of a disease. Isolation refers to separation of the infected persons (or animals) from others for the period of communicability to limit the transmission of the infectious agent to susceptible persons. Quarantine refers to restrictions placed on healthy contacts of an infectious case for the duration of the incubation period to prevent disease transmission if infection should develop (Chin, 1999).

Communicable Disease Control: Introduction SELECTED COMMUNICABLE DISEASES There are several communicable diseases that community health nurses encounter in their practice. They are frequently diagnosed and treated in the community. Tuberculosis (TB) Chlamydia, genital herpes, hepatitis, HIV/AIDS, influenza, pneumonia, syphilis, and viral warts and other

Communicable Disease Control: Introduction • Tuberculosis (TB) • Incidence and Prevalence • Roughly one third of the world’s population is infected with • Mycobacterium tuberculosis. These 2 billion people have the potential for developing active TB at some point in time. Each year, 8 million people worldwide develop active TB and 1.8 million people die. Approximately 80% of TB cases are found in 23 countries; the highest incidence rates are in Africa and southeast Asia

Communicable Disease Control: Introduction • Tuberculosis (TB) • Population at risk • TB disease cases occur predominantly among the following groups: foreignborn persons (46%), the elderly (23%), homeless people • (5%), and individuals infected with HIV (8%). • Higher incidences of TB are found among low-income people, persons with alcohol or drug abuse problems, the underserved, the malnourished, people in correctional facilities, people with other medical conditions, and individuals working where people at risk for TB are grouped together (eg, homeless shelters, drug treatment centers, health care facilities). TB rates are highest among refugees and immigrants, and noncompliance with treatment in all groups is a major factor in continued transmission of the disease and development of MDR organisms. • Children, persons with HIV infection , persons in congregate living such as prisons shelters, long term facilities

Communicable Disease Control: Introduction Tuberculosis (TB) Prevention and Intervention Tuberculin testing, the standard method for evaluating TB infection, is a simple skin test that measures by visible reaction whether the body has had immunologic experience with M. tuberculosis (Table 9–5). From there, evaluation procedures determine the classification status of the disease, ranging from 0 to 5. The two most used terms are infected without current disease (classification 2) and with current TB disease (classification 3) (Table 9–6). The skin test itself is not diagnostic of disease. Treatment: multidrug regimen with direct observation therapy to ensure compliance

Communicable Disease Control: Introduction • Hepatitis • Community health nurses have the key role in TB prevention and treatment. they can: • Identify people at risk • Initiate testing programs • Do follow-up for compliance • Provide education

Communicable Disease Control: Introduction Hepatitis Five viral hepatitis infections are A, B, C, D, and E Each constitutes a serious liver disease caused by a different hepatitis virus. Progress is being made to develop immunizations against various types of hepatitis. Nevertheless, the number of people being infected with hepatitis is globally epidemic.

Communicable Disease Control: Introduction • Hepatitis A: • venerable population : person exposed to unsanitary condition, poor hygiene, sexual contact with infected person, exposed to contaminated food and water • Prevention: a vaccine for those at risk for exposure • Hepatitis A: • venerable population : person who have contact with blood or body fluid of infected person, sexual contact with infected person, people who share needles, newborn infected during birth • Primary Prevention: a vaccination, children, health worker • Secondary Prevention: screening • Tertiary prevention: minimizing effects of the disease

Communicable Disease Control: Introduction • Hepatitis C: • venerable population : intravenous drug users, frequent blood transfusion, sexual contact with infected person, • Prevention: education and screening • Hepatitis D: • venerable population : same as hepatitis B • Primary Prevention: a vaccination, • Hepatitis E: • Usually spread through contaminated water or by fecal-oral contamination • There is no diagnosis test • Has high mortality rate

Communicable Disease Control: Introduction • Influenza • Viral illness characterized by sever muscle aches, fever, headache, sore throat, and cough • Influenza derives its importance from the rapidity with which epidemics evolve, the widespread morbidity, and the seriousness of complications, namely pneumonia • Influenza infections occur primarily in the winter • months, affecting individuals in all age groups and causing • approximately 20,000 deaths and 110,000 hospitalizations • annually in the United States • Primary Prevention: yearly vaccination for vulnerable population, health worker • Secondary Prevention: early diagnosis , and treatment

Communicable Disease Control • Hantavirus • Respiratory disease caused by a virus that is carried and spread by rodents. Person to person transmission may also possible • symptoms: fever, interstitial edema, severe shortness of breath, joint pain, nausea and vomiting • Venerable populations: people exposed to rodent feces and urine contaminated materials and people bitten by rodents • Primary Prevention: rodent control in endemic areas, precautions for decontaminating suspected infectious areas and using protective clothing • Secondary Prevention: testing for hantavirus antibodies • treatment: there is no cure, mortality rate 45%, supportive care such as controlling fever, provide respirtory supports or controlling hemorrhage

Communicable Disease Control • Ebola • Caused by a virus that is can be spread from person to person, or through direct contact with infected blood, semen and secretions • symptoms: bleeding in the mucosa abdomen pericardium and vagina and death • Venerable populations: people living in an area of outbreak , contact with infected person , laboratory worker • Primary Prevention: interrupting of spread of the virus from person to person • Secondary Prevention: testing for Ebola antibodies • treatment: there is no cure, mortality rate 90%,

Communicable Disease Control • Lyme disease • Lyme disease bacterium is transmitted when an infected deer tick bites a person, a bull's-eye rash may appear at the site of tick bite, early symptom like flue • Venerable populations: people living in areas with infected ticks • Primary Prevention: • - Education – avoiding tick endemic areas – inspection for ticks and using insecticide and proper light colored clothing outside doors • Secondary Prevention: • Procedures for properly removed the ticks • Follow-up testing and early diagnosis • treatment: antibiotics

Communicable Disease Control • Pediculosis • is infestation of lice, tiny insects that feed on human blood • there are many type of Pediculosis divided by the body parts • Itching is the symptom • Venerable populations: children, and or people with poor hygiene • Prevention: screening and teaching • treatment: removal of lice by especial shampoo

Communicable Disease Control Prepared by Suhail Al Hu moud