Possible anthrax exposure in
Department of Defense Mail Facility
Samples
taken from a mail facility at the Pentagon at a Remote Delivery Facility (RDF)
on March 10 tested positive for Bacillus anthracis. The
Department of Defense (DOD) briefed all personnel who may have had contact with
the mail at the Pentagon RDF. These employees are being provided with
antibiotics as a prophylactic measure. Based on the route of mail reaching the
Pentagon, CDC has made the following public health recommendations for USPS
postal workers at the V Street Postal Facility in Washington DC where the DOD
mail was processed prior to being sent to the
Pentagon
1) Active medical follow-up should be initiated; that is,
interviews with possibly affected workers for evidence of symptoms and review
of sick leave records.
2) Although risk is considered low, based on an abundance of
caution a course of prophylactic antibiotics (doxycycline or ciprofloxacin;
both are equally effective) is recommended until tests
determining possible exposure to B. anthracis at the V Street facility
can be conducted.
CDC has
also recommended DOD follow up immediately with other non-USPS commercial mail
carriers that deliver to the DOD facility to share the information on:
1) Positive alarm signals
2) Recommendations for USPS workers, so that those carriers
can take steps as needed to follow up with their employees.
Extensive environmental sampling will be conducted in the
Pentagon’s RDF and the V Street Postal Facility to determine the extent of
anthrax contamination.
Clinicians and public health agencies are encouraged to
heighten their surveillance for typical symptoms and exposure history for B.
anthracis. Clinicians should report suspected or confirmed anthrax cases
immediately to your local or state department of health.
Anthrax
causes and transmission
Anthrax is caused by exposure to B. anthracis an
encapsulated, aerobic, gram-positive, spore-forming, rod-shaped bacterium.
Depending on the route of infection, human anthrax can occur in three clinical
forms: cutaneous, inhalational, and gastrointestinal. Direct
skin contact with contaminated animal products can result in cutaneous anthrax. Inhalation of aerosolized spores, such as through
industrial processing of contaminated wool, hair, or hides, can result in
inhalational anthrax. Hemorrhagic meningitis can
result from hematogenous spread of the organism following any form of the
disease.
The incubation period for anthrax is generally <2 weeks.
However, due to spore dormancy and slow clearance from the lungs, the
incubation period for inhalational anthrax may be
prolonged. This phenomenon of
delayed onset of disease is not recognized to occur with cutaneous or
gastrointestinal exposures.
Skin/cutaneous
anthrax
Skin or cutaneous
anthrax is the most common type of naturally-acquired infection. Infection begins as a pruritic papule or vesicle
that enlarges and erodes (1-2 days) leaving a necrotic ulcer with subsequent
formation of a central black eschar (Images at http://www.bt.cdc.gov/Agent/cutaneous.asp]). The lesion is usually painless with surrounding
edema, hyperemia, and regional lymphadenopathy. Patients
may have associated fever, malaise and headache. Historically,
the case-fatality rate for cutaneous anthrax has been <1% with antibiotic
treatment and 20% without antibiotic treatment. There
are rare case reports of person-to-person transmission of cutaneous disease.
See http://www.cdc.gov/mmwr/preview/mmwrhtml/mm5042a1.htm#tab2
for specific treatment of cutaneous anthrax.
Inhalational
anthrax
Inhalational
anthrax is rare but is the most lethal form of
the disease. Disease may initially involve a prodrome
of fever, chills, nonproductive cough, chest pain, headache, myalgias, and
malaise. However, more distinctive clinical
hallmarks include hemorrhagic mediastinal lymphadenitis, hemorrhagic pleural
effusions, bacteremia and toxemia resulting in severe dyspnea, hypoxia and
septic shock. Widened mediastinum is the
classic finding on imaging of the chest, but may initially be subtle (Images at
http://www.bt.cdc.gov/Agent/inhalational.asp
and in the appendices). Case-fatality rates for
inhalational anthrax are high, even with appropriate antibiotics, and
supportive care. Following the bioterrorist
attack in fall 2001, the case-fatality rate among patients with inhalational
disease was 45% (5/11). Person-to person spread
of inhalational anthrax has not been documented.
For case
definitions, treatment guidelines, laboratory testing procedures, etc, see
Anthrax Information for Health Care Providers
http://www.bt.cdc.gov/agent/anthrax/anthrax-hcp-factsheet.asp
For
information on mail handler protection related to anthrax, see
http://www.bt.cdc.gov/agent/anthrax/mail/index.asp
