Title: Treatment
1Treatment
- There is no specific treatment for smallpox and
the only prevention is vaccination. - All individuals that are diagnosed with smallpox
should be isolated immediately due to the highly
contagious nature of the virus. Isolation should
occur in the home or a non-hospital facility
because widespread contamination in hospitals is
a potential threat. - The most that can be done for patients infected
with small pox is supportive therapy and
antibiotics to treat secondary bacterial
infections that could occur. - Some studies suggest that Cidofovir (nucleoside
analog DNA polymerase inhibitor) could possibly
prevent smallpox infection if administered within
1 or 2 days after exposure. The potential use of
this drug is limited because it is administered
intravenously and can cause serious renal
toxicity.
2Identification
- PCR
- In 1995, a new method of identification using PCR
was developed at the Center for Disease Control. - Family-specific primers are used first, then
subgroup-specific primers are used if the former
is not successful in producing the PCR product. - TaqI restriction enzyme is used to differentiate
variola from other orthopoxviruses. - HhaI restriction enzyme is used to differentiate
between the different strains of variola.
3Differential Diagnosis I
4Differential Diagnosis II
5Eradication
- In 1967 the World Health Organization embarked on
a World Eradication Program. - Smallpox is a good candidate for eradication
because - smallpox virus has a single, stable, serotype
- there is no animal reservoir and humans are the
only hosts - the antibody response is prompt, so that exposed
persons can be protected - the disease is easily recognized clinically, so
that exposed persons can be immunized promptly - there is no carrier state or subclinical
infection
6Vaccination
- Smallpox vaccine is made from live vaccinia virus
and does not contain variola virus, the virus
that causes smallpox. Vaccinia virus is a member
of the orthopox virus family. - Vaccination is performed using a bifurcated
needle. A sterile needle with a droplet of
vaccine held by a capillary, is held at right
angles to the skin, while the wrist of the
vaccinator rests against the arm. 15 vigorous
strokes are rapidly made in an area approximately
5 mm in diameter. Blood should appear at the
vaccination site after 15 to 30 seconds. The
site of vaccination is covered with a loose
bandage to prevent individuals from touching the
area and spreading the virus to other parts of
their body. - Neutralizing antibodies developed provide the
vaccinated individual with immunity, but levels
of antibodies decline substantially during a 5 to
10 year period following vaccination.
7Calf-Lymph Vaccine
- Production
- A cow is intentionally infected with the cowpox
virus. - The lymph from the virus filled pustules on the
cows udder are then collected. - The virus is separated from any existing bacteria
and other impurities. - Dryvax is a stored calf-lymph vaccine
manufactured in the 1970s by Wyeth Laboratories. - It is freeze dried and requires dilution before
use. - It contains antibiotics and preservatives.
8Tissue Culture Cell Vaccine
- As of October 2002, tissue culture cell vaccines
are in preparation by Acambis-Baxter
Laboratories. - Two types of cells being used for propagation of
vaccinia virus - Vero monkey kidney cells
- Human fibroblast cell line (MRC5)
- It is thought that these vaccines may cause less
side effects than the calf-lymph vaccine.
9Smallpox Vaccination Program
- On December 13, 2002 President Bush announced a
plan to better protect the American people
against the threat of smallpox attack by hostile
groups or governments - Small Response Teams
- Under the plan, the Department of Health and
Human Services (HHS) will work with state and
local governments to form volunteer Smallpox
Response Teams who can provide critical services
in the event of a smallpox attack. - The federal government is not recommending
vaccination for the general public at this time. - Department of Defense and State Department
Personnel - The Department of Defense (DOD) has vaccinated
the army and certain civilian personnel who may
be deployed in high threat areas. Some United
States personnel assigned to certain overseas
embassies will also be offered vaccination. - Strengthening Homeland Security
- Immediately after the 9/11 attack, HHS began
working, in cooperation with state and local
governments, to strengthen our preparedness for a
bioterrorist attack by expanding the national
stockpile of small pox vaccine. According to the
CDC, the US currently has sufficient quantities
of the vaccine to vaccinate every single person
in the country in an emergency.
10Statistics
11Vaccination Local
12Vaccination Local
13Vaccination Local
14Complications
15Complications
- Postvaccinial Encephalitis
- Between 8 to 15 days after vaccination,
individual develops encephalitic symptoms,-fever,
headache, vomiting, drowsiness, and sometimes
spastic paralysis, meningitic signs, coma, and
convulsions. Recovery is either complete or
associated with residual paralysis, and sometimes
death. - Progressive Vaccinia (Vaccinia Gangrenosa)
- It is a frequently fatal complication in which
the vaccinial lesions fails to heal and
progresses to the adjacent skin with necrosis of
tissue, spreading to other parts of the skin, to
bones, and to viscera. - Eczema Vaccinatum
- Vaccinial skin lesions extended to cover all or
most of the area once, or currently afflicted
with eczema. - Generalized Vaccinia
- A secondary eruption, resulting from blood-borne
dissemination of virus. Lesions emerged between
6 to 9 days after vaccination and were either few
in number of generalized. - Inadvertent Inoculation
- Transmission to close contacts or auto
inoculation to sites such as face, eyelid, mouth,
and genitalia, sometimes occurs.
16VIG
- Vaccinia immunoglobin (VIG) is a collection of
antibodies prepared from the blood of people who
have been vaccinated against smallpox.
Individuals that are at high risk for adverse
reactions to the vaccinia virus can be given VIG
along with the vaccine. It is also used to treat
people who have had adverse affects to the
vaccine. - Individuals that are at high risk to side effects
are those that have the following conditions - Eczema or atopic dermatitis
- Skin conditions that result in a break of the
skin such as burns, shingles, impetigo, herpes,
and psoriasis - Weakened immune system such as someone who has
received a transplant, is HIV positive or
receiving treatment for cancer - Anyone taking immune suppressing medications like
corticosteriods - Pregnant women
- Women that are breastfeeding
- Children under 12 months
- Allergies to the vaccine or any of its components
- Heart disease
17Post exposure Infection Control
- In the event of a smallpox outbreak
- Patients suspected to have smallpox should be
vaccinated to ensure that those who are
misdiagnosed are not placed at risk of getting
smallpox. Vaccination that is administered
within the first few days after exposure may
prevent or significantly reduce subsequent
illness. - All health care workers at clinics or hospitals
that might encounter patients as well as other
disaster response personal, such as police,
firefights, transit workers and mortuary staff
who might have to handle the bodies, should be
vaccinated. - Those individuals that have been in the same
household with infected individuals (face-to-face
contact) should be vaccinated. - Possible establishment of separate hospitals for
smallpox patients. - Areas of infection and those infected should be
isolated and quarantined. - Patients who die of smallpox should be cremated.
18Decontamination
- In a contaminated area, standard precautions of
using gloves, gowns, and masks should be
observed. All waste should be placed in
biohazard bags and incinerated. - Contaminated bedding and clothing should be
autoclaved or laundered in hot water with bleach. - Standard disinfectants, such as hypochlorite and
quaternary ammonia are effective for cleaning
surface.
19Potential Probability vs. Impact
BIOLOGICAL AGENT
NUCLEAR WEAPON
IMPROVISED NUCLEAR DEVICE
CHEMICAL AGENT OR TOXIC INDUSTRIAL CHEMICAL
POTENTIAL IMPACT
RADIOACTIVE MATERIAL
PROBABILITY/LIKELIHOOD
20Limitations of Biological Agents
- It was formerly thought that smallpox was not
very suitable for biological warfare, because it
was too infectious. - An attack would entail a high risk of a worldwide
epidemic, striking even the population of the
attackers. - Effective dissemination difficult.
- Delayed effects can detract from impact.
- Terrorists generally lack the means for
vaccinating large groups of people and have less
opportunity to run large-scale virus cultures. It
has thus been considered far more probable that
they would prefer bacterial infectious matter
such as anthrax, which entails less risk of
uncontrollable epidemics. - Only available on the international WMD black
market.
21Growing Danger?
- Several factors contribute to the growing danger
of smallpox as a biological weapon - A terrorist movement or the military command of a
state could arrive at the conclusion that an
attack with variola in the USA could allow the
epidemic to remain local because of the vigorous
countermeasures expected. If the risk of a
worldwide epidemic seems small, an attack might
be attempted. - The attacks on September 11, 2001 demonstrated
the great ruthlessness and considerable resources
of some terrorists. The fundamentalist ill-will
toward the USA is another driving force and the
attacks in the USA with weapons-grade anthrax
disseminated via the postal service have shown
that terrorists can get access to pathogens. - It is now widely considered that the risks of
variola being used as a weapon have been
underestimated in the past.
22Bio-Weapons Chief
- Former Soviet colonel and doctor Kanatjan
Alibekov, now known as Ken Alibek was the 1st
Deputy Chief of the secret Soviet germ warfare
program, Biopreparat, from 1988 to 1992. - In 1992, Dr. Alibek defected to the US and has
since spent his time briefing U.S. Military,
Intelligence and medical officials about
biological weapons and defenses. Dr. Alibek holds
both M.D. And PhD. Degrees. - In a recent interview Alibek admitted
- for years it (Soviet Union) was researching the
ways to genetically alter variola major by
inserting some new genes in this virus genome. - Q If you had to pick one (1) bio-weapon for an
terrorist attack on the USA, based on former
Soviet doctrine, which one would you chose?A
Smallpox.
23Ebolapox
- This disease is a genetic recombination of
smallpox and Ebola. - It would seem likely that it is more hardy than
Ebola, more like smallpox, with much more
resistance to sunlight, heat, cold, drying, and
humidity. Like smallpox, it could lie dormant for
weeks in the air. - Common symptoms beginning 2-3 days after exposure
are fever, headache, confusion, muscle pain, and
prostration. - Physical examination may reveal only conjunctival
redness, mild hypotension, flushing, and small
skin hemorrhages (petichiae). - Full-blown VHF typically evolves to shock and
generalized mucous membrane hemorrhage, and often
is accompanied by evidence of lung, bone marrow,
kidney, and neurologic involvement.
24Biological Agent Sources
- Home production
- Laboratory / commercial production
- Industrial facilities
- Foreign military sources
- Medical / university research facilities
25Groups That Threaten
- Lone individual
- Identified local or non-aligned terrorist groups
- Internationally sponsored
- Doomsday cults
- Insurgents
26Potential Terrorist Targets
- Enclosed spaces
- Large crowds (high profile events)
- Critical facilities and infrastructure
- Accessible facilities with significant
hazard / damage potential
(materials in transit) - Facilities of interest to terrorists cause
27Why Bio Terrorism?
- Agents are available relatively easy to
manufacture. - Large amount not needed in enclosed space.
- NBC incident difficult to recognize.
- Easily spread over large areas.
- Psychological impact.
- Can overwhelm existing resources.
- Great value!
- According to the Stockholm international peace
research institute, the cost to inflict civilian
casualties is 2000 per square kilometer with
conventional weapons, 800 with nuclear weapons,
and 1 with biological weapons.
28Biological Warfare Agents Aerosol Particle Size
Maximum respiratory infection is caused by a
particle in the 1 to 5 micron size range. This
particle will reach the alveoli during normal
respiration.
Larger particles (trapped in upper airways)
1-5 micron particles (enter alveoli)
29Breaking Devices
- Point Source
- Common Items
- Moderate downwind hazard
Vacuum Bottle
Light Bulb
30Bursting and Exploding Devices
- PointSource
- Moderate downwind hazard
- May destroy agent
- Detectable
- Multiple hazard potential
Timer
Explosive with igniter
Agent reservoir
31Spraying Devices
- Point Source
- Aerosol can
- Garden sprayer
- Moderate/significant
- downwind hazard
- Line Source
- Moving vehicles
- Significant downwind hazard
Pressurized agent
Agent release valve
Pressure release valve
Pressure vessel
Agent reservoir
Dissemination nozzle
32Impact of Dissemination Devices
Downwind Hazard
Device
Most Likely Agent
Moderate
Breaking
Chemical
Moderate
Bursting
All
Moderate
Explosive
Radiological (C/B Possible)
- Significant (Line Source) - Moderate/Significant
(Point Source)
Spray
Biological or Chemical
Unpredictable
Vector
Biological or Chemical