Children And Anthrax This article was written on 11/11/01 from resources
available on that date.
Please check the CDC Web site for updated information.
Anthrax is making headlines as an agent of biological warfare,
and as a weapon of bioterrorism.
The last epidemic of inhalational anthrax occurred in the former
Soviet Union, in the industrial city of Sverdlovsk, in 1979.
The 66 deaths were due to inhalation of aerosolized spores of
anthrax, which were accidentally released from the nearby military
microbiology laboratory.
Anthrax is an acute infectious disease caused by the bacterium Bacillus anthracis.
B. anthracis is a bacterium which is distributed worldwide.
It exists in contaminated soil in the form of extremely resistant spores.
Anthrax is most prevalent among cattle, horses, sheep, and goats
which have grazed on contaminated land, or which have ingested contaminated feed.
Most cases in industrialized countries are associated with exposure to goat hair imported from countries where anthrax is common among livestock.
In the U.S. these bacteria remain endemic in the soil of Texas,
Oklahoma, and the lower Mississippi valley.
Anthrax may have been responsible for two of the plagues which afflicted Egypt in 1491 BC.
The Greek poet and scientist Virgil gave a detailed description
of this disease.
Around 1877, John Bell first described woolsorters’ disease in England.
This form of inhalational anthrax is linked to processing of infected hides and wool in enclosed factory spaces.
WHAT IS ANTHRAX?
It is a square-ended, non-motile, aerobic, Gram-positive rod with
a centrally located spore.
The anthrax spores are highly resistant to drying, boiling, and most
disinfectants.
Resistant spores can survive in the soil for decades.
B. anthracis spores germinate when exposed to human (or animal) tissue or blood.
Anthrax is not spread from person to person.
Children may be affected by three forms: inhalational, cutaneous, or gastrointestinal.
HOW MANY FORMS OF ANTHRAX ARE THERE?
There are three forms of anthrax: inhalational, cutaneous, and gastrointestinal.
Inhalational Anthrax:
This is the most lethal form of anthrax.
It results from the inhalation of anthrax spores 1-5 microns in diameter.
The 8,000 to 50,000 spores needed to infect someone are smaller than a
speck of dust.
Dormant spores travel to tiny sacs in the lungs where they germinate into bacteria.
Children develop symptoms 1-5 days after exposure, with nonspecific
respiratory symptoms of cough associated with low-grade fever,
fatigue, malaise, and muscle aches.
Cutaneous Anthrax: "Anthrax" means coal in Greek.
The cutaneous form eventually produces skins lesions which resemble the color of coal.
The disease is initiated when spores enter the skin through cuts or abrasions.
Handling wool or other by-products of infected animals can result in spores
lodging in skin cuts.
After an incubation period of 12 hours to 7 days the spores germinate,
multiply, and produce a toxin that causes an initial skin lesion
which resembles an insect bite or pimple.
A painless ulcer the size of a quarter appears after a few days.
It then develops a black center.
Gastrointestinal and Pharyngeal Anthrax:
This form occurs after ingestion of anthrax spores in contaminated and undercooked meat.
The spores germinate in the abdominal lymph nodes where they produce
a hemorrhagic lymphadenitis and bacteremia.
In oropharyngeal anthrax, fever and neck swelling occur in the presence
of an oral cavity lesion.
Soft tissue edema and dramatic cervical lymph node enlargement follow.
WHAT MAKES ANTHRAX SO DEADLY?
Anthrax is now being used as a biologic weapon for terrorism.
Its spores remain viable for years, and can be easily stored
and transported.
Inhaled anthrax spores can produce a lethal infection despite antibiotic therapy.
Anthrax bacteria produce and release a deadly toxin.
The anthrax toxin has 3 components:
edema factor (EF), lethal factor (LF), and protective antigen (PA).
EF is responsible for the edema at the site of infection, as well as the
inhibition of neutrophil function.
LF destroys cells, injures local blood vessels, and causes thrombosis.
LF stimulates the release of tumor necrosis factor alpha and interleukin-1B, which contribute to sudden death.
PA facilitates the transfer of EF and LF into the body’s cells.
WHAT ARE THE SIGNS AND SYMPTOMS OF ANTHRAX INFECTION?
Inhalational Anthrax:
Inhalational anthrax has two phases.
In the initial phase, it appears as a nonspecific illness – similar
to influenza.
It is characterized by: mild fever, malaise, muscle soreness,
dry cough, and chest or abdominal pain.
The second phase of inhalation anthrax begins abruptly within 2 or 3 days.
It involves additional fever, severe difficulty breathing, sweating,
cyanosis, and occasionally stridor.
Death occurs within 24 to 36 hours after the start of the second
phase of the illness.
Cutaneous Anthrax:
The first sign of cutaneous anthrax is a painless pruritic papule.
Within one or two days, a large vesicle develops.
A gelatinous swelling surrounds the lesion.
The vesicle ruptures, forming an ulcer which is covered by a characteristic
black eschar.
The eschar dries and falls off in a week or two.
Gastrointestinal Anthrax:
The symptoms of GI anthrax appear 2 to 5 days after the ingestion
of undercooked meat containing spores.
The symptoms start out with nausea, fever, vomiting, and abdominal pain.
They rapidly progress to severe, bloody diarrhea.
Oropharyngeal anthrax may also occur.
HOW IS ANTHRAX DIAGNOSED IN CHILDREN?
The physician first needs to determine if there has been a credible
“known” exposure to anthrax.
Second, the physician obtains vital signs, examines the child,
and assesses the neurologic, circulatory, and respiratory status.
Signs of altered mental status which may suggest shock, sepsis,
or meningitis are noted.
Third, the physician notes any erythema, edema, or skin lesions
(papules, vessicles).
Nasal swab cultures should not be used to diagnose cases of anthrax.
The reason is that nasal swab cultures are not very sensitive,
so a negative swab culture result will not rule out exposure to anthrax.
Initial, presumptive, laboratory identification is done using
a direct Gram’s-stained smear of skin lesion fluid, cerebrospinal fluid, or blood.
Microscopic examination will show large, non-encapsulated, broad,
gram-positive rods.
In a Gram’s stain preparation, the spore appears as an unstained area.
Anthrax forms non-hemolytic colonies when grown on sheep’s-blood-agar
nutrient.
The physician may consider performing a PCR test on clinical specimens
to document the presence of anthrax.
Confirming tests are done a level B laboratory of the Laboratory
Response Network for Bioterrorism.
WHAT IS THE TREATMENT FOR ANTHRAX IN CHILDREN?
It is important to stress that giving antibiotics to a child who
has not been examined by a physician could mask symptoms of the
illnesses, as well as lead to drug-resistant bacteria.
On the other hand, a high index of clinical suspicion, and rapid
administration of antimicrobial therapy by a physician are necessary
for prompt diagnosis and treatment of anthrax.
Start therapy with IV antibiotics:
Ciprofloxacin 10-15 mg/kg/dose every 12 hours.
OR
Doxycylcline 2.2 mg/kg/dose every 12 hours.
AND
One or two additional antimicrobials.
The physician may then switch to oral antimicrobial therapy when
appropriate.
Antimicrobial therapy should be continued for a total of 60 days
to ensure that all spores have germinated and that they have been eradicated.
HOW CAN ANTHRAX INFECTION BE PREVENTED?
Simple measures such as handwashing can prevent skin (cutaneous)
anthrax, just by washing away the spores.
At this time, anthrax vaccine is not recommended for children under
18 years of age.
Drugs and medical supplies which are used to fight anthrax
are kept in eight guarded warehouses in the U.S.
Each stockpile holds 50 tons of supplies.
Push packages can reach any American city, if needed, within 12 hours.
This information was developed on 11/11/01 from resources available on that date.
Please check the CDC Web site for updates.
Lecture material on anthrax is also available.
The New England Journal of Medicine has published an article on anthrax.
It described the bacteriology, pathogenesis, epidemiology, clinical features,
diagnosis, antimicrobial therapy, and hospital infection control of anthrax.
Swartz MN: Recognition and management of anthrax – an update.
The New England Journal of Medicine. November 29, 2001; 345(22).
