Communicable Diseases: Definition - PowerPoint PPT Presentation

Loading...

PPT – Communicable Diseases: Definition PowerPoint presentation | free to view - id: 3b2ec7-NzBjY



Loading


The Adobe Flash plugin is needed to view this content

Get the plugin now

View by Category
About This Presentation
Title:

Communicable Diseases: Definition

Description:

Defined as any condition which is transmitted directly or indirectly to a person from an infected person or animal through the agency of an intermediate animal ... – PowerPoint PPT presentation

Number of Views:266
Avg rating:3.0/5.0
Slides: 98
Provided by: wvlcUwate
Category:

less

Write a Comment
User Comments (0)
Transcript and Presenter's Notes

Title: Communicable Diseases: Definition


1
Communicable Diseases Definition
  • Defined as
  • any condition which is transmitted directly or
    indirectly to a person from an infected person or
    animal through the agency of an intermediate
    animal, host, or vector, or through the inanimate
    environment.
  • Transmission is facilitated by the following
    (IOM)
  • more frequent human contact due to
  • Increase in the volume and means of
    transportation (affordable international air
    travel),
  • globalization (increased trade and contact)
  • Microbial adaptation and change
  • Breakdown of public health capacity at various
    levels
  • Change in human demographics and behavior
  • Economic development and land use patterns

2
CD- Modes of transmission
  • Direct
  • Blood-borne or sexual HIV, Hepatitis B,C
  • Inhalation Tuberculosis, influenza, anthrax
  • Food-borne E.coli, Salmonella,
  • Contaminated water- Cholera, rotavirus, Hepatitis
    A
  • Indirect
  • Vector-borne- malaria, onchocerciasis,
    trypanosomiasis
  • Formites
  • Zoonotic diseases animal handling and feeding
    practices (Mad cow disease, Avian Influenza)

3
Importance of Communicable Diseases
  • Significant burden of disease especially in low
    and middle income countries
  • Social impact
  • Economic impact
  • Potential for rapid spread
  • Human security concerns
  • Intentional use

4
Communicable Diseases account for a significant
global disease burden
  • In 2005, CDs accounted for about 30 of the
    global BoD and 60 of the BoD in Africa.
  • CDs typically affect LIC and MICs
    disproportionately.
  • Account for 40 of the disease burden in low and
    middle income countries
  • Most communicable diseases are preventable or
    treatable.

5
Communicable Disease Burden Varies Widely Among
Continents
6
Communicable disease burden in Europe
7
Causes of Death Vary Greatly by Country Income
Level
8
CDs have a significant social impact
  • Disruption of family and social networks
  • Child-headed households, social exclusion
  • Widespread stigma and discrimination
  • TB, HIV/AIDS, Leprosy
  • Discrimination in employment, schools, migration
    policies
  • Orphans and vulnerable children
  • Loss of primary care givers
  • Susceptibility to exploitation and trafficking
  • Interventions such as quarantine measures may
    aggravate the social disruption

9
CDs have a significant economic impact in
affected countries
  • At the macro level
  • Reduction in revenue for the country (e.g.
    tourism)
  • Estimated cost of SARS epidemic to Asian
    countries 20 billion (2003) or 2 million per
    case.
  • Drop in international travel to affected
    countries by 50-70
  • Malaria causes an average loss of 1.3 annual GDP
    in countries with intense transmission
  • The plague outbreak in India cost the economy
    over 1 billion from travel restrictions and
    embargoes
  • At the household level
  • Poorer households are disproportionately affected
  • Substantial loss in productivity and income for
    the infirmed and caregiver
  • Catastrophic costs of treating illness

10
International boundaries are disappearing
  • Borders are not very effective at stopping
    communicable diseases.
  • With increasing globalization
  • interdependence of countries more trade and
    human/animal interactions
  • The rise in international traffic and commerce
    makes challenges even more daunting
  • Other global issues affect or are affected by
    communicable diseases.
  • climate change
  • migration
  • Change in biodiversity

11
Human Security concerns
  • Potential magnitude and rapid spread of
    outbreaks/pandemics. e.g. SARS outbreak
  • No country or region can contain a full blown
    outbreak of Avian influenza
  • Bioterrorism and intentional outbreaks
  • Anthrax, Small pox
  • New and re-emerging diseases
  • Ebola, TB (MDR-TB and XDR-TB), HPAI, Rift valley
    fever.

12
Tuberculosis
  • 2 billion people infected with microbes that
    cause TB.
  • Not everyone develops active disease
  • A person is infected every second globally
  • 22 countries account for 80 of TB cases.
  • gt50 cases in Asia, 28 in Africa (which also has
    the highest per capita prevalence)
  • In 2005, there were 8.8 million new TB cases 1.6
    million deaths from TB (about 4400 a day)
  • Highly stigmatizing disease

13
Tuberculosis and HIV
  • A third of those living with HIV are co-infected
    with TB
  • About 200,000 people with HIV die annually from
    TB.
  • Most common opportunistic infection in Africa
  • 70 of TB patients are co-infected with HIV in
    some countries in Africa
  • Impact of HIV on TB
  • TB is harder to diagnose in HIV-positive people.
  • TB progresses faster in HIV-infected people.
  • TB in HIV-positive people is almost certain to be
    fatal if undiagnosed or left untreated.
  • TB occurs earlier in the course of HIV infection
    than many other opportunistic infections.

14
Global Prevalence of TB cases (WHO)
15
Tuberculosis
16
(No Transcript)
17
Tuberculosis Control
  • Challenges for tuberculosis control
  • MDR-TB - In most countries. About 450000 new
    cases annually.
  • XDR-TB cases confirmed in South Africa.
  • Weak health systems
  • TB and HIV
  • The Global Plan to Stop TB 2006-2015.
  • an investment of US 56 billion, a three-fold
    increase from 2005. The estimated funding gap is
    US 31 billion.
  • Six step strategy Expanding DOTS treatment
    Health Systems Strengthening Engaging all care
    providers Empowering patients and communities
    Addressing MDR TB, Supporting research

18
Malaria
  • Every year, 500 million people become severely
    ill with malaria
  • And it causes 30 of Low birth weight in newborns
    globally.
  • gt1 million people die of malaria every year. One
    child dies from it every 30 seconds
  • 40 of the worlds population is at risk of
    malaria. Most cases and deaths occur in SSA.
  • Malaria is the 9th leading cause of death in LICs
    and MICs
  • 11 of childhood deaths worldwide attributable to
    malaria
  • SSA children account for 82 of malaria deaths
    worldwide

19
Annual Reported Malaria Cases by Country (WHO
2003)
20
Global malaria prevalence
21
Malaria Control
  • Malaria control
  • Early diagnosis and prompt treatment to cure
    patients and reduce parasite reservoir
  • Vector control
  • Indoor residual spraying
  • Long lasting Insecticide treated bed nets
  • Intermittent preventive treatment of pregnant
    women
  • Challenges in malaria control
  • Widespread resistance to conventional
    anti-malaria drugs
  • Malaria and HIV
  • Health Systems Constraints
  • Access to services
  • Coverage of prevention interventions

22
HIV/AIDS
  • In 2005, 38.6 million people worldwide were
    living with HIV, of which 24.7 million
    (two-thirds) lived in SSA
  • 4.1 million people worldwide became newly
    infected
  • 2.8 million people lost their lives to AIDS
  • New infections occur predominantly among the
    15-24 age group.
  • Previously unknown about 25 years ago. Has
    affected over 60 million people so far.

23
HIV Co-infections
  • Impact of TB on HIV
  • TB considerably shortens the survival of people
    with HIV/AIDS.
  • TB kills up to half of all AIDS patients
    worldwide.
  • TB bacteria accelerate the progress of AIDS
    infection in the patient
  • HIV and Malaria
  • Diseases of poverty
  • HIV infected adults are at risk of developing
    severe malaria
  • Acute malaria episodes temporarily increase HIV
    viral load
  • Adults with low CD4 count more susceptible to
    treatment failure

24
Global HIV Burden
25
HIV/AIDS
  • Interventions depend on
  • Epidemiology mode of transmission, age group
  • Stage of epidemic concentrated vs. generalized
  • Elements of an effective intervention
  • Strong political support and enabling
    environment.
  • Linking prevention to care and access to care and
    treatment
  • Integrate it into poverty reduction and address
    gender inequality
  • Effective monitoring and evaluation
  • Strengthening the health system and Multisectoral
    approaches
  • Challenges in prevention and scaling up treatment
    globally include
  • Constraints to access to care and treatment
  • Stigma and discrimination
  • Inadequate prevention measures.
  • Co-infections (TB, Malaria)

26
Avian Influenza
  • Seasonal influenza causes severe illness in 3-5
    million people and 250000 500000 deaths yearly
  • 1st H5N1 avian influenza case in Hong Kong in
    1997.
  • By October 2007 331 human cases, 202 deaths.

27
Avian Influenza
  • Control depends on the phase of the epidemic
  • Pre-Pandemic Phase
  • Reduce opportunity for human infection
  • Strengthen early warning system
  • Emergence of Pandemic virus
  • Contain and/or delay the spread at source
  • Pandemic Declared
  • Reduce mortality, morbidity and social disruption
  • Conduct research to guide response measures
  • Antiviral medications Oseltamivir, Amantadine
  • Vaccine still experimental under development.
  • Can only be produced in significant quantity
    after an outbreak

28
Confirmed human cases of H5N1
29
Migratory pathway for birds and Avian influenza
30
Neglected diseases
  • Cause over 500,000 deaths and 57 million DALYs
    annually.
  • Include the following
  • Helminthic infections
  • Hookworm (Ascaris, trichuris), lymphatic
    filariasis, onchocerciasis, schistosomiasis,
    dracunculiasis
  • Protozoan infections
  • Leishmaniasis, African trypanosomiasis, Chagas
    disease
  • Bacterial infections
  • Leprosy, trachoma, buruli ulcer

31
Communicable Disease and Human Security
  • Part 2 - Mounting an Effective Global Response

32
Approaches to Interventions
  • Personal Responsibility and action
  • Utilitarian Approaches Greatest good for the
    greatest number
  • Including non Health Systems Interventions.
  • Regulations and Laws
  • Partnerships and Collaboration
  • Enlightened Self Interest

33
Personal Responsibility and action
  • Improved hygiene and sanitation
  • Hand washing, proper waste disposal, food
    preparation and handling.
  • Information, education and behavior change
  • Changing harmful household practices
  • Livestock handling, knowledge about contagion
  • Cultural and social norms
  • Self reporting of illnesses and compliance with
    interventions and treatment.

34
Utilitarian Approaches Greatest good for the
greatest number
  • Reliance on personal responsibility
  • not always the optimal option given different
    knowledge levels and values.
  • Public good nature of the interventions
  • Social Isolation and Quarantine measures
  • Home treatment Isolation
  • Mass vaccination programs and campaigns
  • Polio, small pox, DPT, Hepatitis, Yellow fever
  • Mass treatment programs
  • Onchocerciasis, de-worming programs.
  • For some CDs, intervention in other sectors is
    required
  • Environmental health elimination of breeding
    sites, spraying
  • Agricultural practices such as poultry handling
    and exposure to soil pathogens during farming.

35
Regulations and Laws
  • National response remains the bedrock of
    intervention
  • National laws and capacities vary.
  • International Regulations and laws introduced
  • 1851 International Sanitary regulations in
    Europe following cholera outbreak
  • 1951- international sanitary regulation by WHO.
  • 1969- Replaced by the International Health
    regulation
  • Minor changes in 1973 and 1981
  • cholera, plague, yellow fever, smallpox,
    relapsing fever and typhus
  • 2005 Revised International Health Regulation
  • Challenge of enforceability of international
    agreements.

36
Regulation and laws WHO 2005 International
health regulation
  • IHR (2005) is a legally binding agreement among
    member states of WHO to cooperate on a set of
    defined areas of public health importance.
  • Arrived at by consensus of all member countries
    of WHO, with clear arbitration mechanisms
  • Its elements include
  • Notification
  • National IHR Focal Points and WHO IHR Contact
    Points
  • Requirements for national core capacities
  • Recommended measures
  • External advice regarding the IHR (2005)

37
Partnerships and Collaboration
  • Collaboration vs. coercion
  • Importance of partnerships
  • MDG 8 Develop global partnerships for
    development
  • Comparative advantage of partners
  • Inclusiveness
  • Examples of partnerships
  • Over 70 Global health partnerships available
  • Examples include the Stop-TB program, GFATM, RBM,
    UNAIDS, GAVI, Global Outbreak Alert and Response
    Network, GAIN, bilateral and multilateral
    organizations.

38
Isnt Donor Collaboration Wonderful?
INT NGO
WHO
CIDA
3/5
UNAIDS
GTZ
RNE
UNICEF
Norad
WB
Sida
MOF
USAID
T-MAP
UNTG
PMO
CF
DAC
GFCCP
PRSP
PEPFAR
HSSP
GFATM
MOEC
MOH
SWAP
CCM
NCTP
CTU
CCAIDS
NACP
PRIVATE SECTOR
CIVIL SOCIETY
LOCALGVT
Source WHO Mbewe
39
A paradigm shift - Enlightened Self interest
  • Communicable diseases have no borders.
  • Predominantly affect the poor, and poor countries
  • Also affect richer households and countries.
  • Interventions are non-rival, non-exclusive and
    have positive externalities.
  • Elimination and control of certain communicable
    diseases increases global health security.
  • Limited financial incentives for the market to
    drive needed innovation in research and drug
    development
  • Mismatch between global health need and health
    spending
  • Global health security is therefore inextricably
    tied to the effective control of CDs in
    developing world.

40
Global Mismatch Between Disease Burden and Health
Spending
41
Global Mismatch Between Disease Burden and Health
Spending
42
Future Population Growth Will be in LICs and MICs
43
Key principles of an Effective Global Response
  • Respect for the value of each life
  • Behind every statistic is an individual
  • Understanding of the social context that govern
    individual decision making
  • Disease Surveillance and reporting
  • Management and containment of outbreaks
  • Strong legal and regulatory framework
  • Sustained and predictable financing
  • Building national health systems

44
World Banks involvement
  • Relevance to our mandate
  • CDs disproportionately affect the poor and LICs
    and MICs
  • Enormous economic consequences
  • Major constraint to achieving the MDGs
  • Major source of financing for poor countries
  • This position is rapidly changing with the
    entrance of newer players in DAH such as Gates
    foundation, Bilaterals, multilaterals.
  • Call for innovative financing schemes

45
World Bank
  • 430 million committed to malaria booster
    projects in Africa
  • By 2008, 21 million bed nets and 42 million ACT
    doses would have been distributed.
  • As of June 2007, the World Bank had approved
    financing of 377 million for 40 projects in 45
    countries in all six geographic regions to combat
    Avian influenza
  • Cumulative WB commitment to HIV/AIDS is over 2.5
    billion

46
Sources of Development Assistance for Health
Source Michaud 2006
47
Emerging viral diseases what are the threats and
how should we respond? Professor John Mackenzie
Professor of Tropical Infectious Diseases Curtin
University of Technology, Perth
Emerging viral diseases what are the threats and
how should we respond? Tuesday 4 September 2007
48
(No Transcript)
49
  • Emerging diseases on rise
    Date 21/02/2008
  • An international research team has provided the
    first scientific evidence that deadly emerging
    diseases have risen steeply across the world, and
    has mapped the outbreaks' main sources. They say
    new diseases originating from wild animals in
    poor nations are the greatest threat to humans.
    Expansion of humans into shrinking pockets of
    biodiversity and resulting contacts with wildlife
    are the reason, they say. Meanwhile, richer
    nations are nursing other outbreaks, including
    multidrug-resistant pathogen strains, through
    overuse of antibiotics, centralised food
    processing and other technologies. The study
    appears in the Feb. 21 issue of the leading
    scientific journal Nature. Emerging
    diseases-defined as newly identified pathogens,
    or old ones moving to new regions--have caused
    devastating outbreaks already. The HIV/AIDS
    pandemic, thought to have started from human
    contact with chimps, has led to over 65 million
    infections recent outbreaks of SARS originating
    in Chinese bats have cost up to 100 billion.
    Outbreaks like the exotic African Ebola virus
    have been small, but deadly.
  • Despite three decades of research, previous
    attempts to explain these seemingly random
    emergences were unsuccessful. In the new study,
    researchers from four institutions analysed 335
    emerging diseases from 1940 to 2004, then
    converted the results into maps correlated with
    human population density, population changes,
    latitude, rainfall and wildlife biodiversity.
    They showed that disease emergences have roughly
    quadrupled over the past 50 years. Some 60 of
    the diseases travelled from animals to humans
    (such diseases are called zoonoses) and the
    majority of those came from wild creatures. With
    data corrected for lesser surveillance done in
    poorer countries, "hot spots" jump out in areas
    spanning sub-Saharan Africa, India and China
    smaller spots appear in Europe, and North and
    South America.

50
  • Emerging diseases on rise
    Date 21/02/2008
  • "We are crowding wildlife into ever-smaller
    areas, and human population is increasing," said
    coauthor Marc Levy, a global-change expert at the
    Center for International Earth Science
    Information Network (CIESIN), an affiliate of
    Columbia University's Earth Institute. "The
    meeting of these two things is a recipe for
    something crossing over." The main sources are
    mammals. Some pathogens may be picked up by
    hunting or accidental contact others, such as
    Malaysia's Nipah virus, go from wildlife to
    livestock, then to people. Humans have evolved no
    resistance to zoonoses, so the diseases can be
    extraordinarily lethal. The scientists say that
    the more wild species in an area, the more
    pathogen varieties they may harbour. Kate E.
    Jones, an evolutionary biologist at the
    Zoological Society of London and first author of
    the study, said the work urgently highlights the
    need to prevent further intrusion into areas of
    high biodiversity. "It turns out that
    conservation may be an important means of
    preventing new diseases," she said.
  • About 20 percent of known emergences are
    multidrug-resistant strains of previously known
    pathogens, including tuberculosis. Richer
    nations' increasing reliance on modern
    antibiotics has helped breed such dangerous
    strains, said Peter Daszak, an emerging-diseases
    biologist with the Consortium for Conservation
    Medicine at the Wildlife Trust, another Earth
    Institute affiliate, who directed the study.
    Daszak said that some strains, such as lethal
    variants of the common bacteria e. coli, now
    spread widely with great speed because products
    like raw vegetables are processed in huge,
    centralised facilities. "Disease can be a cost of
    development," he said.

51
  • Emerging diseases on rise
    Date 21/02/2008
  • The group's analyses showed also that more
    diseases emerged in the 1980s than any other
    decade-likely due to the HIV/AIDS pandemic, which
    led to other new diseases in immune-compromised
    victims. In the 1990s, insect-transmitted
    diseases saw a peak, possibly in reaction to
    rapid climate changes that started taking hold
    then. Team members soon hope to study this
    possibility and its future implications.
  • Daszak says the study has immediate uses. "The
    world's public-health resources are
    misallocated," he said. "Most are focused on
    richer countries that can afford surveillance,
    but most of the hotspots are in developing
    countries. If you look at the high-impact
    diseases of the future, we're missing the point."
    Team members say nations must share more
    technology and resources in hot-spots to reduce
    risk. "We need to start finding pathogens before
    they emerge," said Daszak.

52
Global Distribution of Relative Risk of an EID
Event                     
                                                  
                         Caption Global
distribution of relative risk of an EID event.
Maps are derived for EID events caused by a,
zoonotic pathogens from wildlife, b, zoonotic
pathogens from nonwildlife, c, drug-resistant
pathogens and d, vector-borne pathogens. The
relative risk is calculated from regression
coefficients and variable values in Table 1
(omitting the variable measuring reporting
effort), categorized by standard deviations from
the mean and mapped on a linear scale from green
(lower values) to red (higher values). Credit Jon
es et. al., Nature Usage Restrictions Please
credit Jones et. al., Nature
A
B
C
D
53
Geographic Origins of EID events from 1940 to 2004
Caption Global richness map of the geographic
origins of EID events from 1940 to 2004. The map
is derived for EID events caused by all pathogen
types. Circles represent one degree grid cells,
and the area of the circle is proportional to the
number of events in the cell. Credit Jones et.
al., Nature
54
WNV In USA
WNV is spreading rapidly throughout the
country
12/11/02
55
WNV in USA 12/31/2002
  • In 2002, 5 States Il, MI, OH, LA and IN accounted
    for
  • 62.2 of WNV cases
  • 70.5 of deaths

www.cdc.gov/od/oc/media/wncount.htm
56
West Nile Virus
Clinical Presentation
  • Incubation period 3 - 14 days
  • 20 develop West Nile fever
  • 1 in 150 develop meningoencephalitis
  • Advanced age primary risk factor for severe
    neurological disease and death
  • Mild dengue-like illness of sudden onset
  • Duration 3 - 6 days
  • Fever, lymphadenopathy, headache, abdominal pain,
    vomiting, rash, conjunctivitis, eye pain,
    anorexia
  • Symptoms of West Nile fever in contemporary
    outbreaks not fully studied

57
Severe Acute Respiratory Syndrome (SARS)
58
Severe Acute Respiratory Syndrome (SARS)
  • The Initial Epidemic
  • Outbreak of atypical pneumonia in Hong Kong in
    March 2003
  • Between 03/11/03 and 03/25/03 156 patients were
    hospitalized with SARS
  • 138 were identified as secondary or tertiary
    cases as a result of exposure to index case(s)
  • 112 secondary cases
  • 26 tertiary cases
  • Includes 69 HCWs
  • 20 MDs
  • 34 Nurses
  • 15 Allied HCWs
  • 54 patients on ward or visitors
  • 16 medical students
  • 32 of the 138 patients (23.2) had severe
    respiratory failure
  • 5 patients died (3.6)
  • All had been hospitalized with a major medical
    condition

Lee N et al. NEJM April 7, 2003. www.nejm.org
59
Severe Acute Respiratory Syndrome (SARS)
  • The Clinical Presentation- Initial 138 Cases
  • Incubation period was 2-10 days from initial
    exposure to onset of fever
  • Median incubation period was 6 days
  • The most common clinical symptoms were
  • Fever (100) gt 100.50
  • Chills, rigors or both (73.2)
  • Myalgia (60.9)
  • Cough (57.3)
  • Headache (55.8)
  • Dizziness (42.8)
  • Less common symptoms included
  • Sore throat, sputum production, coryza, nausea,
    vomiting, and diarrhea

Lee N et al. NEJM April 7, 2003. www.nejm.org
60
Severe Acute Respiratory Syndrome (SARS)
  • Routes of Transmission
  • The principal way SARS appears to be spread is
    through droplet transmission1,2
  • Namely, when a SARS patient coughs or sneezes
    droplets into the air and someone else breathes
    them in.
  • It is possible that SARS can be transmitted
    through the air or from objects that have become
    contaminated.1,2
  • People at risk 1,2
  • Direct close contact with an infected person
  • Sharing a household with a SARS patient
  • HCWs who did not use infection control procedures
    while caring for a SARS patient.
  • In the United States, there is no indication of
    community transmission at this time.1,2
  • CDC. April 4, 2003. http//www.cdc.gov/ncidod/sars
    /faq.htm.
  • http//www.ada.org/prof/prac/issues/topics/sars.ht
    ml

61
Severe Acute Respiratory Syndrome (SARS)
  • Respiratory illness of viral etiology with onset
    since February 1, 2003, and
    the following criteria
  • Measured temperature gt 100.5F (gt38 C)

    AND
  • One or more clinical findings of respiratory
    illness
  • Cough
  • Shortness of breath
  • Difficulty breathing
  • Hypoxia
  • Radiographic findings of either pneumonia or
    acute respiratory distress syndrome
  • AND

http//www.cdc.gov/ncidod/sars/casedefinition.htm
62
Severe Acute Respiratory Syndrome (SARS)
  • Travel within 10 days of onset of symptoms to an
    area with documented or suspected community
    transmission of SARS
  • Peoples' Republic of China
  • Mainland China
  • Hong Kong Special Administrative Region
  • Hanoi, Vietnam
  • Singapore
  • Toronto, Canada (04/21/03)
  • OR

http//www.cdc.gov/ncidod/sars/casedefinition.htm
63
Severe Acute Respiratory Syndrome (SARS)
  • Close contact within 10 days of onset of symptoms
    with either a person with a respiratory illness
    who traveled to a SARS area or a person known to
    be a suspect SARS case.
  • Close contact is defined as having
  • Cared for
  • Lived with
  • Direct contact with respiratory secretions and/or
    body fluids of a patient known to be suspect SARS
    case.

http//www.cdc.gov/ncidod/sars/casedefinition.htm
64
Severe Acute Respiratory Syndrome (SARS)Case
Definition 04/20/03
  • Suspected Case
  • Travel within 10 days of onset of symptoms to an
    area with documented or suspected community
    transmission of SARS
  • Excludes areas with secondary cases limited to
    healthcare workers or direct household contacts)
  • Travel includes transit in an airport in an area
    with documented or suspected community
    transmission of SARS. Areas with documented or
    suspected community transmission of SARS
  • People's Republic of China
  • Mainland China
  • Hong Kong Special Administrative Region
  • Hanoi, Vietnam
  • Singapore
  • Toronto, Canada.

http//www.cdc.gov/ncidod/sars/casedefinition.htm
65
Severe Acute Respiratory Syndrome (SARS)Case
Definition 04/20/03
  • Suspected Case
  • Close contact within 10 days of onset of symptoms
    with a person
    known to be a suspect SARS case.
  • Close contact is defined as having cared for,
    having lived with, or having direct contact with
    respiratory secretions and/or body fluids of a
    patient known to be suspect SARS case.
  • Probable Case
  • A suspected case with one of the following
  • Radiographic evidence of pneumonia or
    respiratory
    distress syndrome
  • Autopsy findings consistent with respiratory
    distress
    syndrome without an identifiable cause

http//www.cdc.gov/ncidod/sars/casedefinition.htm
66
Severe Acute Respiratory Syndrome (SARS)
  • Cause of SARS
  • Scientists at CDC and other laboratories have
    detected a
    previously unrecognized coronavirus in
    patients with SARS.1-4
  • Confirmed as causative agent by WHO on 04/16/03
  • Virus a member of the coronavirus family, never
    before seen in humans

1. http//www.cdc.gov/ncidod/sars/casedefinition.h
tm 2. Peiris J et al, Lancet 2003
http//image.thelancet.com/extras/03art3477web.pdf
3. Drosten C et al. NEJM 2003 www.nejm.org 4.
Ksiazek T et al. NEJM 2003 www.nejm.org
67
Severe Acute Respiratory Syndrome (SARS)
  • Cause of SARS
  • Coronaviruses are a group of viruses

    that have a halo or crown-like (corona)
    appearance when
    viewed under a microscope.
  • These viruses are a common cause of mild to
    moderate upper-respiratory illness in humans and
    are associated with respiratory,
    gastrointestinal, liver and neurologic disease in
    animals.
  • Coronaviruses can survive in the environment for
    as long as three to four hours.

1. http//www.cdc.gov/ncidod/sars/casedefinition.h
tm 2. Peiris J et al, Lancet 2003
http//image.thelancet.com/extras/03art3477web.pdf
3. Drosten C et al. NEJM 2003 www.nejm.org 4.
Ksiazek T et al. NEJM 2003 www.nejm.org
68
Severe Acute Respiratory Syndrome (SARS)Dental
School, University of Maryland
  • Precautions for Dental Patients Who
    May Have
    Been Exposed to SARS
  • While taking initial medical histories and at
    periodic updates, all dental patients at the
    Dental School will routinely be asked about
  • Recent travel of patient or immediate family
    members to areas where SARS is endemic
  • Peoples' Republic of China
  • Mainland China
  • Hong Kong Special Administrative Region
  • Hanoi, Vietnam
  • Singapore
  • Toronto, Canada

DePaola L, 2003, University of Maryland Baltimore
69
Severe Acute Respiratory Syndrome (SARS)Dental
School, University of Maryland
  • Precautions for Dental Patients Who May Have
    Been Exposed to SARS
  • Recent respiratory illness
  • Cough
  • Shortness of breath
  • Difficulty breathing
  • Hypoxia
  • Radiographic findings of either pneumonia or
    acute respiratory distress syndrome
  • Close contact with anyone suspected of being
    infected with SARS
  • While taking initial medical histories and at
    periodic updates, all dental patients at the
    Dental School will routinely be asked whether
    they have a history of and/or S S suggestive
    of SARS

DePaola L, 2003, University of Maryland Baltimore
70
Severe Acute Respiratory Syndrome (SARS)Dental
School, University of Maryland
  • Precautions for Dental Patients Who May Have Been
    Exposed to SARS
  • Patients with a medical history or signs and
    symptoms of SARS will be immediately referred to
    the University of Maryland Medical System, or
    their private physician for medical evaluation
    for possible infectiousness.
  • Such patients should not remain in the Dental
    School any longer than required to arrange the
    referral.
  • Elective dental treatment will be deferred until
    a physician confirms that the patient does not
    have SARS.

DePaola L, 2003, University of Maryland Baltimore
71
Severe Acute Respiratory Syndrome (SARS)
  • Infection Control Procedures Suspected Cases1-3
  • Isolate patients in a separate waiting area
  • Give patients a surgical mask to wear
  • Instruct patients to cover mouth when coughing or
    sneezing
  • HCWS utilize surgical mask
  • Healthcare personnel should apply
  • Standard precautions
  • Hand hygiene
  • Soap and water or alcohol-based hand rub
  • Contact precautions when aerosol-generating
    procedures
    are being performed on patients who may have
    SARS.
  • Gloves, gown, and eyewear
  • Airborne precautions
  • Respiratory protective devices with a filter
    efficiency of greater than or equal to 95
  • Recommended with confirmed SARS patients
  • http//www.cdc.gov/ncidod/sars/infectioncontrol.ht
    m.
  • http//www.ada.org/prof/prac/issues/topics/sars.ht
    ml
  • DePaola L, 2003, University of Maryland Baltimore

72
Severe Acute Respiratory Syndrome (SARS)
  • Infection Control Procedures
  • For known SARS patients
  • Due to rapid development of symptoms it is
    unlikely
    that SARS will be seen in
    the dental office
  • HCWS utilize NIOSH respirators appropriate for
    TB
  • Defer all elective treatment until patient has
    been evaluated
  • Refer patients for urgent/emergency care to
    locations equipped with TB Isolation Areas, i.e.
    local hospitals
  • Follow the Guidelines for Preventing the
    Transmission of Mycobacterium tuberculosis in
    Health-Care Facilities http//www.cdc.gov/mmwr/pre
    view/mmwrhtml/00035909.htm
  • In summary, healthcare personnel should apply
  • Standard precautions
  • Contact precautions
  • Airborne precautions
  • http//www.cdc.gov/ncidod/sars/infectioncontrol.ht
    m.
  • http//www.ada.org/prof/prac/issues/topics/sars.ht
    ml
  • DePaola L, 2003, University of Maryland Baltimore

73
Hantavirus Pulmonary Syndrome (HPS)
  • An outbreak of unexplained illness occurred in
    May 1993 an area of the Southwest shared by NM,
    AZ, CO, and UT (Four Corners).
  • A number of previously healthy young adults
    suddenly developed acute respiratory symptoms
    about half soon died. 
  • A hantavirus, which is transmitted by rodents,
    was suspected.
  • The virus named Sin Nombre virus (SNV) and its
    principal carrier, the deer mouse were positively
    identified. 
  • A "bumper crop" of rodents there,

    due to heavy rains during
    the spring
    of 1993.
  • Determined that person to person

    transmission of SNV was unlikely.
  • SNV had actually been present, but

    unrecognized, at least as early as 1959.
  • Since the discovery in 1993, hantavirus

    pulmonary syndrome (HPS) has been

    identified in over half of the states
    of the U.S.

74
Influenza
75
Influenza
  • Acute, febrile illness, usually self limited
  • Headache, malaise, myalgias
  • Fever - 104oF-106oF (days 1-3)
  • URI symptoms
  • Nasal discharge, sore throat, cough (days 2-7)
  • Cervical adenopathy (children gt adults) and
    rhonchi
  • Attack rate 10 - 40
  • Viral shedding
  • One day before - until 10 days after symptom
    onset
  • Peak day 3-4
  • Shedding is prolonged in young children
  • Transmission
  • Person to person via small particle aerosols
  • Virus is relatively stable and favors low
    humidity and cool
    temperatures

www.cdc.gov/ncidod/diseases/flu/fluvirus.htm
76

http//www.cdc.gov/nip/Flu/Public.htmFacts
77
Flu Facts
  • Influenza (flu) is a serious disease
  • Flu is not a cold!
  • It is far more dangerous than a bad cold
  • The virus infects the lungs.
  • It can lead to pneumonia/other sequellae.
  • Every year in the USA approximately
  • 114,000 people are hospitalized
  • 20,000 people die because of the flu.
  • Most who die are over 65 years old. But small
    children less than 2 years old are as likely as
    those over 65 to have to go to the hospital
    because of the flu.   

http//www.cdc.gov/nip/Flu/Public.htmFacts
78
Influenza Vaccine
  • Type Inactivated split or whole virus
  • Route/schedule 0.5 IM annually
  • Efficacy 70-90
  • Indications
  • Age gt 65
  • Health care or day care workers
  • Nursing home/chronic care residents
  • Adults and children with pulmonary and
    cardiovascular disorders, chronic metabolic
    disease (diabetes mellitus),
    renal dysfunction, immunosuppression
  • Teenagers and children on ASA
  • Women in the 2nd and 3rd trimester of pregnancy
  • Contraindications Anaphylaxis to eggs
  • Side effects
  • Local pain, occasional myalgias and rare allergic
    reactions

www.cdc.gov/ncidod/diseases/flu/fluvirus.htm
79
Prevention and Control of InfluenzaRecommendatio
ns of the Advisory Committee on Immunization
Practices (ACIP)
  • The 2002 recommendations include five principal
    changes or updates
  • The optimal time to receive influenza vaccine is
    during Oct. and Nov.
  • However, because of vaccine distribution delays
    during the past 2 years, ACIP recommends that
    vaccination efforts in Oct. focus on persons at
    greatest risk for influenza-related complications
    and health-care workers and that vaccination of
    other groups begin in November.
  • Vaccination efforts for all groups should
    continue into Dec. and later,
    for as long as vaccine is available.
  • Because young, otherwise healthy children are at
    increased risk for flu-related hospitalization,
    influenza vaccination of healthy children aged
    6--23 months is encouraged when feasible.
  • Vaccination of children aged gt6 months who have
    certain medical conditions continues to be
    strongly recommended.
  • The 2002--2003 trivalent vaccine virus strains
    are A/Moscow/10/99 (H3N2)-like, A/New
    Caledonia/20/99 (H1N1)-like, and B/Hong
    Kong/330/2001-like strains.
  • A limited amount of influenza vaccine with
    reduced thimerosal content will be available for
    the 2002--2003 influenza season.

MMWR. April 12, 2002 / 51(RR03)1-31
80
  • The 2002--2003 trivalent vaccine virus strains
    are
  • A/Moscow/10/99 (H3N2)-like
  • A/New Caledonia/20/99 (H1N1)-like
  • B/Hong Kong/330/2001-like strains

http//www.cdc.gov/mmwr/preview/mmwrhtml/rr5103a1.
htm
81
Tuberculosis
82
Tuberculosis (TB)
The number one single infectious disease killer
  • TB is not on the decline.
  • One third of the world's population is
    infected with TB
  • In 1999 TB caused 8,000 deaths/day
  • The most deaths from TB in history
  • 7- 8 million people become infected with TB/year
  • 5-10 of these people will develop active TB
  • Between 1993 and 1996, TB increased 13
  • TB accounts for more than 1/4 of all preventable
    adult deaths the developing world.

nfid.org/factsheets
83
Tuberculosis (TB)
The number one single infectious disease killer
  • Someone is newly infected with TB
    every second !
  • TB is the leading killer of women
  • TB outranks all causes of maternal mortality
  • TB creates more orphans than
    any other infectious disease
  • TB is the leading cause of death
    among HIV-positive individuals

nfid.org/factsheets
84
Tuberculosis Transmission
  • Caused by Mycobacterium tuberculosis
  • Spread by
    - Airborne route

    - Droplet nuclei
  • Affected by
    - Infectiousness of
    patient -
    Environmental conditions
    - Duration of exposure
  • Most persons exposed do not become infected

85
PathogenesisLatent M.tuberculosis Infection
  • Inhaled droplet nuclei with M. tuberculosis
  • - Reach alveoli
  • - Are taken up by alveolar macrophages
  • - Reach regional lymph nodes
  • - Enter bloodstream and disseminate
  • Chest radiograph may have transient abnormalities
  • Specific cell-mediated immune response controls
    further spread

86
PathogenesisActive M. tuberculosis Infection
  • Active disease state
  • Symptoms present
  • Cough
  • Fever
  • Chills
  • Night sweats
  • May be infectious
  • Disease both treatable preventable

87
Diagnosis
of Active TB
  • History and epidemiologic clues
  • Think TB!!!
  • Chest X-ray
  • Tuberculin skin test
  • AFB smear
  • AFB culture
  • Nucleic acid amplification
  • Fast but sensitivity poor in smear neg.
  • Empiric treatment trial

88
Administering the Tuberculin Skin Test
  • Inject intra-dermally
  • 0.1 ml of 5 TU PPD tuberculin
  • Produce wheal
  • 6 mm to 10 mm in diameter
  • Do not recap, bend,
    or break needles,

    or remove needles
    from syringes
  • Follow universal
    precautions for
    infection
    control

89
Reading the Tuberculin Skin Test
  • Read reaction
  • 48-72 hours
    after injection
  • Measure only induration!
  • Record reaction in
    millimeters

90
Dental Offices
  • .No specific dental procedure
    has been
    classified as cough inducing.
    In light of these
    observations
    the following additional
    considerations appear
    prudent in dental settings

Guidelines for Preventing the Transmission of
Mycobacterium tuberculosis

in Health-Care Facilities,
MMWR October 28, 1994 / 43(RR13)1-132
91
Risk of Occupational
TB Transmission
Private Dental Offices
  • Considered minimal
  • Follow CDC/ADA
    guidelines
  • No OSHA regulations
    (to date)

Guidelines for Preventing the Transmission of
Mycobacterium tuberculosis
in
Health-Care Facilities, MMWR October 28, 1994 /
43(RR13)1-132
92
TB Guidelines
  • During initial medical history and periodic
    updates DHCW should
  • Routinely ask all patients
    about a history of TB
  • And signs and
    symptoms
    suggestive of TB

Guidelines for Preventing the Transmission of
Mycobacterium tuberculosis


in Health-Care
Facilities, MMWR October 28, 1994 /
43(RR13)1-132
93
TB Guidelines
  • All elective dental care should be
    deferred until a physician determines
  • That the patient doesnt have TB
    or
  • Anti-TB therapy has
    been rendered and
    the patient is no
    longer infectious!

Guidelines for Preventing the Transmission of
Mycobacterium tuberculosis

in Health-Care
Facilities, MMWR October 28, 1994 /
43(RR13)1-132
94
TB Guidelines
  • If urgent care must be provided for
    a patient with active TB or signs symptoms
    suggestive of TB,
  • TB isolation practices
    should be implemented
  • DHCW should use appropriate respiratory
    protection while performing procedures on these
    patients

Guidelines for Preventing the Transmission of
Mycobacterium tuberculosis

in Health-Care Facilities, MMWR October
28, 1994 / 43(RR13)1-132
95
Emergency Dental Treatment
for TB Patients
  • Perform treatment in facilities with TB isolation
    capability
  • Use recommended respiratory protection
  • Fit tested HEPA filter mask
  • Select least invasive treatment options
  • Accomplish definitive care after patient is no
    longer infectious
  • Sputum Negative for Acid Fast Bacillus (AFB)
  • Guidelines for Preventing the Transmission of
    Mycobacterium tuberculosis

    in Health-Care
    Facilities, MMWR October 28, 1994 /
    43(RR13)1-132

96
Tuberculosis
  • Dental-care in high risk facilities
  • Use engineering controls similar to those in
    general use areas of medical facilities with
    similar risk profile.
  • Evaluation of Dental HCW TB symptoms
  • Evaluate promptly
  • Do not return to clinic until
  • TB Diagnosis is ruled out or
  • DHCW is on therapy and non-infectious

Guidelines for Preventing the Transmission of
Mycobacterium tuberculosis
in
Health-Care Facilities, MMWR October 28, 1994 /
43(RR13)1-132

97
CDC/ADA Dental Office
TB Recommendations
Written Plan Should Include
  • Protocol for referring TB patients
    to dental isolation facility
  • Protocol for identifying and referring
    patients for medical evaluation for TB
  • DHCW education, training, counseling
    and screening
  • Periodic risk assessment and updates

Guidelines for Preventing the Transmission of
Mycobacterium tuberculosis
in
Health-Care Facilities, MMWR October 28, 1994 /
43(RR13)1-132
About PowerShow.com