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RDTE Proiect No. l-X-6-65704-D-Ll4USATECOM Proiect No. 5-C0-473-000-026

DTC Proiect No. DTC-TR-73-517

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@-trL]OINT CB TECHNICAL DATA

SOURCE BOOK tU]

VOLUME VI I I

Bacterial Diseases (U)

Part Two: Anthrax (U)

FEBRUARY 1973

(J a /j:,-araz ler:';

HEADQUARTERS ' DESERET TEST CENTER ' FORT DOUGLAS, UTAH O 84I I3

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DTC 73-27

Copy '' of 5 CoPies

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I]NCLASSIFIED

(u) r'oREwoRD (u)

This document was prepared in compliance with Department of the Armyletter, I'Joint contacE Point for chemical-Biological- (cB) Fiel_d TestData (u) r" 10 March L967, r.rhich direcred Deseret Test center (DTc)to pubLish and maintain a joint chemical-biological weapons systemsource book.

The Source Book is organized into volumes by agent category. In eachvol-ume, Parameter val-ues and confidence levels derived. from field,laboratory, and chamber test data are presented. This volume alsoPresents modeLs and submodels that identify and define the parametersfor which numerical values are required in estimating the capabilitiesof weapons systerns. The weapons systerns for which data are presentedincl-ude those of each of the Armed Services that had been standardizedor t)rye-classified and Ehose that were in an advanced stage of developmentprior to the presidential poliey statement of 25 Novernber 1969 regardingbiological weapons.

The material presented in each volume is organized in such a manner thatit can be used by (1) the research and development corununity as inputto system design and analysis studies and (2) the operational conrnunityas input to the Preparation of system-performance tabLes for inclusionin field nnnuals, firing tabl-es, and other presentations of munitionsexpenditure and effectiveness information.

The assistance of GEOMET, Incorporated, who prepared major portionsof this document under DA ContracE No. DAAD 09-69-C-0078, is ackknowledged.

Comments and suggesEions regarding the adequacy or accuracy of thematerial presented herein and any assistance needed in its use should beaddressed to:

Commander

Deseret Test CenterATTN: STEPD-PS-A(S)Fort Douglas, UEah 84113

I]NCI,^ASSIFIED

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5-1

6-1

6-2

6-3

6-4

IINCIJ.SSIFIED

(u) TLLUSTRATTONS (U)

Response of Cynomolgus Monkey to Aerosols of B.Anthracis.....

Total and Regional Deposition of Inhaled Particlesin Relation co Aerodynamic Particle Size.

Freeze-Thaw Cycling Tests in the TRI Logistic Study

Concentration of Viable Bacillus Anthracis Spores inAerosols Maintained in the.Dynamic Aerosol Toroidsat Four Relative HumidiEy Percentages and 27 oC.

for a Period of 138 Hours

TRI Downwind Dosage Predictions for Aerial ReleasesDuring Windspeeds of 3 Meters per Second.

TRl Downwind Dosage Predictions for Aerial ReleasesDuring Windspeeds of 6 lleters per Second. .

TR2 Dc'ranwind Dosage Predictions for Aerial ReleasesDuring Windspeeds of 3 Meters per Second.

TR2 Downwind Dosage PredicLions for Aerial ReleasesDuring Windspeeds of 6 Meters per Second.

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6-3

6-4

6-5

TTNCI.^A''SSIFIED

7

Number

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4-4

4-5

4-6

4-7

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5-2

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- 4-5

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IINCLASStiEI

(u) TABLES

TR1 Initia I Concentrations fc: i= - -.::=: I -=-Forc Detrick Aerosol Tests.

Harvest ConcenEraEions and tsu-; : -:::::- -: --Composite Lots of DBO-Produce: l--

Decay Constants and Half-Life. ::: I : -:=----Various Temperatures.

Estimated Storage Decay Pare;-^-:::--= : :: =i =r-- -

\rariations in Guinea Pig Resp---=::-=- --i: -::Stored f or Different Time Per::,:.= :: -==-.r:-lures

Viable Spore Count.Millilirer x 10s)

. 4_2

4-9

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E6lR4 Bomblet Dissemination E::::- =.::- - : ..;.=- - -:-as a Function of Time and Te=:=-:=: =: --- ,;:--Storage 4-L3

TotaI Aerosol Decay Rate f or i:::- =-- - ' j--:-=--r: --=-r

from che E61R4 Bomblet in the I::: - -:l-===

Function of Time and Temperai -:: :: -i'-; . - :- -=- 4- 13

Characleristics of }lunitions l::=: -= :: - -- :-r1---:r-=iIB. AnEhracis.

Dissemination Efficiencies cfTes t Ct"rambers ;- 18

:- 18

:--20

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Estima:ed TR2 Disseminaiion E::://10 Nozzle with Tornado Feece:

Efficiencl' of Dissemina tion c:and A/845y-4 Spray Tanks.

Estimated Dissemination Ef fic-Systemrs with Agent TR

Estinated Total Decay Rates (-

ToLaI Decey Ra tes f or the I'{i- -

Charnbe:: Tes ts

I'NCI.^A,SSE

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T'NCI,^ASSIFIED

(u) TABLES (U) (Continued)

Number

5-3 Total Decay Rates (100k) for TR2 Based on Chamber

5-4

5-5

6-7

7-L

7-2

l-3

7-4

7-5

Trials at Fort Detrick . .

Biological Decay Rates (Percent/Minute) for TRl underUltraviolet Stress

BG and TRl Total Decay Rates from Chamber Tests UsingE61R.4 Bomblets

Estimated Downwind Distances for Effective Dosage(EED = 5.3 x 106 org rnin/m3) of TRl and TR2 Releasedfrom an Aerial Line Source

Recommended Chemotherapy Regimens for Anthrax.

Effects of Various Disinfectants on the Spores of B.AnEhracis Suspended in Solution. .

Formaldehyde Gas Srerilization of FaciliLies, Materials,and Equipment.

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Characteristi

Amounts of BeExperiments.

cs of Selected Decontaminants

rapropiol-actone (BPL) Released in Ship

X1

UNCIJ.SSIFIED

I

CHAPTER 3

(s) AGENT Cr{AMCTERTSTTCS (u)

(U) Biological Nature of the Organism

a. Morphological Characteristics. Bacillus anthracis is an aerobic,sporulating, gram-posiEive, nonmotile, rod-shaped bacterium. Cel1s mayvary in size from 1 to 1.5 by 3 to 10 microns, depending on the conditionsof growth. Cells sporul-ate readily when gror.m in laboratory culture, butthey do not sporulate when in living tissue. Presumably, sporulationoccurs in cells grown in living animal tissue when the cell-s are dischargedfrom the animal body inEo a suitable medium such as soil or organic resi-dues. Spores are ellipsoidal to cylindrical, 0.8 to 1.0 by 1.3 to 1.5microns, and they occupy a median position in the cell-. The cells areusually in chains and have square ends. Cells thaE grovr in the animalbody or laboratory culture in an atmosphere containing 10 to 15 percentCO" form capsules. ( L'2,3)

b. Cultural Characteristics. B. anthracis requires free oxygen forgrowEh and spore formation; it is therefore considered an aerobe. Itgrows well on most cultural media at temperatures ranging from 12 to 45oC. B. anthracis is generally nonhemolyEic. Typically, colonies ofvirulent strains of the organism, when grown on nutrient agar, are greyish-white in color and have hair-like tufts around the peripherial surface ofEhe colony (these are sometimes referred to as medusa-head-type co1-onies).The surface of the colony is granul-ar in appearance as compared to theusually small, round, smooth-cype colonies of the avirulent strains.However, when viruLenE organisms are grown on special media such as serumagar in Ehe presence of a high CO. atmosphere, smooth colonies of virulentencapsulated cells are formed. Encapsulation has been associated withvirulence of the organism; however, this association may be fortuitous.Encapsulation has not been directly associated with the ability of theorganism to prcduce toxin. Encapsulation is relaEed Eo the resistance ofthe B. ant.hracis ce11 towith phagocytos:s.

in" action of opsonin, an anEibody associaEed

Avirulent mucoid muEanEs have been described. These variant.s areencapsulated when grown on nutrienE agar in air. Asporogenous variantshave also been ceveloped which may be eiEher virulent or avirulent.(1-4)

c. Persistency. The anEhrax bacillus can persist in the sgore formindefinit"lyl" rriT and organic matter, particularly if the environmenLis dry. The vegetaEive organism may also grow and reproduce in soil andorganic materia-s. Hcrqrever, vegetative ce1ls of B. anthracis do notsurvive well in :omperition with the saprophytic o?StrGsE tt.r. so!i,and in some sclls the organism does not become esEablished as an indigenousmember of ihe soil microflora. However, the organism occurs enieni.cally

Ir

in many areas of the world as a natural soil inhabitant.(].t1ts) The

organism survives for long periods on various animal products, such as

hides, wool, hair, bone meal, and meat product.s, and it may be trans-ported by commerce in these materials

3-3. (U) Characteristics of the Disease

a. Ncmenclature. Anthrax is preCominantly a disease of animals(catt1e, sheep, horses, and swine). In animals, Lhe disease is alsoknor,in by such names as splenic fever, charbon, and milzbrand. The diseasemay exist in man as a malignant pustule (cutaneous anthrax), as inhala-tion anthr:x, or as intestinal anthrax. Inhalation anthrax (frequentlyreferred tc as pulmonary anthrax) most frequently occurs among workersin industrial plants where dust from processed materials contaminated wichB. anthracls enters the respiratory system of the worker. Because ofits freque:it occurrence in workers in specific jobs, it is kncnrn by suchnames as wcolsorter I s disease and ragsorter t s disease. lntestinal anthraxresults fr--m ingestion of the sPores. It has been reported in humans,though inf:equently. It is relativel-y ccrTunon in animals, whereas inhala-tj-on anthr:x infrequenLly occurs in aninals. Cutaneous anthrax or malig-nant pustule is the most frequent forirr of t:re disease in both anim:1sand humans,

J-:

UNCTASSIFIED

b. Transmission. AnEhrax is generally transmitted to man fromanimals or conEaminaEed material associaEed with animals. No man-to-mantransmission has been reported. Many mammals are suscepEible to anthraxas a result of natural infection or by laboratory-induced infection.Birds are relatively refracEory; however, ant,hrax has been reported insome carnivorous birds and in the osErich. Scavenging birds may carryand disperse t,he organism. Cold-blooded animals are generally refractoryEo Ehe disease; however, c€s€s have been reported in frogs and some fish.The cuEaneous form of the disease occurs when the anthrax organism entersthe hosE through an abrasion in the skin and forms a lesion at the surfaceof the skin at the point of enEry. Early historical reports of rag-sorterts disease and woolsorterrs disease indicated fairly frequentoccurrence. However, improvements in sanitaEion and methods of handlinganimals and animal producEs have conEr.ibuted to a reduction in inhalationanthrax. As an internal infection, this disease may occur after inges-tion of contaminated material or by inhalation of cont.aminated dust orothenrise aerosolized B. anthracis organisms. The disease is not con-sidered infect,ious, because iE is not easily nor readily Eransmitted,as evidenced by the widespread occurrence of the organisms in the soil inrnany areas of the world with low incidence of the disease. Horve'rer, inenzootic areas, Large-scale epidemics among animal populations haveoccurred. The disease is most commonly transmitEed in animals by inges-tion of contaminated food. Some experimental work has indicated Ehatthe organism may be transmitted from hosE to host by flies, mosquitos,and oEher vecEors. ( I '4-6)

Svmptoms and Diagnosis

(1) Cutaneous anthrax is characterized by a local lesion whichbegins from a small red nncule and enlarges to form a central vesicleof clear fluid surrounded by satellite vesicles. The lesion becomesnecrotic, and a black eschar is characteristic of older lesions. TheIesion is not painful, but the regional lymph nodes are Eender. Theorganism may be isolated from the lesion, parEicularly during earlydeveloprnenE. Malaise, fever, headache, and general prostraEion develop,and the intensiEy of the symptoms vary with the hosE, the stage of Ehedisease, and apparently tviEh Ehe number of organisms involved in theinitial infection, i.e., the dose. In the early stage, pulmonary andintestinaL anchrax symptorns are mild and nonspecific. This early stageis followed by a very rapid onsec of che advanced disease, associatedwit.h a nassive invasion by the organism throughout Che body.(e)

(2) The two stages of human inhalation ant.hrax described beloware characterized as insidious onset and acuEe toxemia.

(a) Insidious onset is associated with mild fever, malaise,fatigue, Ryslgia, a nonproducti-ve cough, and frequenElv a sensaEion ofprecordial oppression. This inicial stage typically lasts for several<ieys . Tie pa tient's clinj-ca1 co:rdir:on may irnprcve slightiy rowarC theend of !ris stage.(a)

)- a

UNCLASSIFIED

L----

I'NCTASSIFTED

(b) Acute toxemia develops suddenly, with acute dyspnea(shorcness of breath) and subsequent cyanosis (1ack of blood at thebody surface). The patient aPPears moribund, with accelerated pulseand respiration. The body Eemperature, although usually elevated to102 oF. or more, ffi€y suddenly become subnormal because of shock.Profuse perspiration commonly occurs. Subcutaneous edema of chest andneck may exist. Stridor is common, and chest examination disclosescrepitant rales associated with fluid in the lungs.(6'a'e) The averageduration of this acute stage is less than 24 hours, and it terminaEesin death. Consciousness is usually nEintained until death, except v/iththe infrequent occurrence of meningitis, when disorientation and comaoccur.

(3) Since the clinical manifestations of inhalation and intesti-nal anthrax are nonspecific and inconsistent, diagnosis of the diseaseremains a major problem. Diagnosis of inhalation anthrax can be aidedby the following

(") A history of occupational exposure by natural infection.(1o)(Plotkin, et al.r(8) suggest that rreatment should be started on thebasis of suspicion or association rather than on positive diagnosis.)

(b) Roentgenographic examination revealing acute wideningof the mediastinum. (8

' 1o )

(.) Positive blood cultures indicating disseminated anthraxinfection; occasionally the bacilli may be identified in the centrifugedsediment of blood treated with 3-percent aceEic acid solution andstained with Wrightts stain.(10) Hot",r"t, if man reacts in a mannersimilar to monkeys and chimpanzees, septicemia may be deEected by bloodsmear examination about 10 hours letore death.(ro)

ver]-.(rt)

II

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(4) The following laboratory methods forinfection in i11 or dead animals may be employed

(") Animal inoculationva1uable. liinety-five Percent ofinoculation will occur on days 2,should then be verified by smears

in guinea pigs or mice is extremelythe deaths resulting from animal3, and 4; the presence of B. anthracistaken from the inoculated animals.

fication of anthrax

(") Direct microscopic examination of suspected material,when stained. satisfactorily, will reveal gram-positive bacilli that are1 to 1.5 microns in diameLer and 5 io B microns 1ong. In blood smears,most of the bacilli will be single cel1s, but short chains may exist ifthe animal has been dead for a few hours.

(b) Inoculation of tryPtose sov agar plates with infectedblood will show medusa-headed colonies in 12 to 24 hours.

3-4

TINCIASSIFIED

ITNCLASSIFIED

(d) Fluorescent antibodyblood smears and tissue sectionsB. anEhracis.

techniques, which work equally well, can be used for rapid identificationon

of

menE ofnot iniEporEions

the datediseasetion ofexposed

d. Onset and Duration. Following cutaneous infection, develop-Ehe lesion usually occurs within 2 ot 3 days. If treacment isiated, Ehe infection may spread systemically co bacterimic pro-and death may occur within 4 to 7 days. For inhalation anthrax

!n humans,and as longinha 1a tionsymptoms.lrz) For a recent single human case of inhalation anEhrax,

Ehe incubation period is said to be as short as 24 hours(a)as from 4 to 5 days.(s) For man, death resulting from

anthrax occurs from 13 hours to 12 days folLcnuing onset of

of exposure \{as fairly accurately idenEified. OnseE of thefor this case e/as approximately 6 days to insidious manifesta-illness and 10 days to acute illness and death.(13) Monkeys,under similar circumstances, had onset times of 10 to L7 days.(r+)

I'lechanism of Infection

(1) The mechanism(s) oi infection by B. anthracis is notcompletely understood,,!yt iq aPPears to be a quantitaLive chemicalpropercy of the agent.(o'J Virulence of B. anthracis may Possibly be

associated with particular cellular antigens, with the ability or in-ability of the anthrax organism to be phagocytized by the host macro-phages, with the abilicy or inability of phagocytic ce1ls to detoxifyEhe agent,, or wifh Che ability of the agenc to reproduce within thesece11s. No data have been found co indicaEe that the material from whichthe spore was derived, i.e., !/eE material or dry maEerial, has anyeffecE on the infective process.

(2) Experiments seem to indicate that the vegetative ce11

injected inEo Ehe body kills the guinea pig in a shorter time than thespore. While in Ehe germination stage, the ce11 probably develops an

active, integrated physiology and remains noncapsulated- This isprobably Che period of its greatest susceptibility to destruction- The

encapsul-ated cel1 is protected to some degree by the polyglutamic acidcapsule. Anthracidal substances in the blood appear to be the principalmeans c€ destruction of anthrax bacilli in the blood, and phagocytosisis of iess importancu. (" ) The first noticeable effect of anthracidalnnterial on the bacillus is a loss of capsule, accompanied by a loss ofsEaini::g Droperties, followed by fragmentation. AcEually, t'anthracidalsubsE.ancest' is a general term embracing many facEors. Dog organs containa decacsulating agent, and there seems to be both a heat-stable and a

heat-la'oile anthracidal factor in guinea pig Leucocytes.

(3) PaEhogenes is . of i-nhathe prr:;rary stege, during whichthe an::nal body and establish a

a per:--C of secondary grcwth in

lation anthrax has three distinct srages:s?ores nove from the lung alveoli intoprimary infection in the lymph syst'm;iire reti-culoendothelial svstem anci

3-5

UNCIASSIFIED

IINCI-ASSIHED

generaLLzed distribution in the body associated with a more or lessconstanE bacteremia; and the preterminal septicenlic stage, which isthe stage most characteristic of this disease.(s) Histological methodshave shcrrn that spores deposited from an aerosol onlo the epithelialsurface of the lung are ingested by macrophage ce11s on Ehe surface ofthe lung. These cel1s may be sessile or mobile. The mobile macro-phage cel1s containing ingested sPores migrate through Lhe undamagedepithelium and enter the lymph stream, then move on to infiltrat.e thetracheobronchial nodes. During this time or after reaching the lymphnodes, the spore germinates and develops into the vegetative ce1l;infection begins by proliferation of vegetative bacilli freed from thephagocytic cel1. This vegetative ce11 moves along rhe efferent lymphchannel through the lymph duct into the venous blood.(s'1s) There isg eneral agreement that B. anthracis characteristically does not developvegetatively in the tn.tg to ""Glneumonia.

(4) Apparently, organisms entering the blood from the ly*phsysEem do noE proliferate in the blood, but are retsained by and multiplyin the tissues of the reticuloendothelial system, chiefly the liver andspleen, until they exceed the retaining capacity of the tissues. Thenvegetative ceLls pass into the bloodstream, and terminal septicemia isinitiaEed. Multiplication of organisms conEinues until the death ofthe animal. The extent of growth of organisms, or terminal Ievel,depends on the reLative-immuniEy leve1 of che host. During the septi-cemic phase in guinea pigs (6 to t hours before death or 3 hours beforethe development of the critical blood bacilli concentration), 61 percentof the bacilli in the animal body were in the spleen and 16 percent werein the blood. At death, this ratio changed to 16 percent in the spleenand,72 percent in the b1ood.(s) After this critical 1eve1 of bacterialconcentration is reached, the septicemia may be eliminated by antibioEictherapy, but the animal will die because of Eoxic reacLion. The time todeath is closely relaEed to the time afEer reaching the critical con-centration before initiation of antibiotic treatment.(e) Death resultsfrom the action of toxin(s) released by the growing organisms, whichpredomiaately produces symptoms of shock in the hosE. The implicationthat tosin alone accounts for the anthrax virulence has not beendefinitely confirmed.(5) Whether these experimenral observations inanimals are duplicated in humans with anthrax is presently unknown.

(5) The extracellular toxin produced by B. anthracis containsthree separate componencs: the edema faclor (EF), protective antigen(PA), and the leEhal factor (tF). These components are not toxic wheninjected alone into animals.(]5) The edema factor remains biologicallyactive and produces an edema when mixed with protective anEigen; however,the letral factor is no longer lechal when injected in combination withproEecttve antigen. In monkeys, the ultinnte effect of the t,oxin on thecentral nervous system'is anoxia, that is, deprivation of oxygen to thebody tlssues. This is caused by a lack of oxygenation of the blood,either ry itself or in combination with decreased blood flow. The

3-6

t]NCI.^ASSIFIED

terminal anoxia could arise through (1) a direct effect on the respiratorycenter in the central nervous system, causing a respiratory failure and a

lack of oxygenation, (2) a teEanic paralysis of the intercosEal and dia-phragmatic muscles, arising from increased cenEral nervous system (CNS)

discharges and again resulting in respiratory paralysis and lack of oxy-genation, and (3) a cardiovascular failure mediated by the increasedcent,ral nervous system discharges, Producing a generalized smooth muscle

constriction. This would also contribute Eo lack of oxygenation throughbronchial- constriction.(17) The results obtained with the inacEivatedforms of the toxin (inactivated wiCh antiserum or heat) suggest thatsurvival depends on continuation of respiration, because the toxin comPo-

nent affecting the respiratory center has been inactivated or because thecomponents thaE cause the CNS-cardiovascular failure have been alteredin iuch a \ray thaE rhe animal is able to reestablish enough blood flowto prevent terminal anoxia.(17t18) in" components(s) of the toxin specif-ica1ly responsible for the central nervous sysEem action have not yetbeen idenrified.

f.. Susceptibilitv/Severitv. Almost all animals, including humans,

areto'o@b1etoanthrax.Theherbivoraarethemostsusceptible; of these, the disease is most common in cattle and sheep'

It is also common in horses,'mules, and s\^Iine, although swine are lesssusceptible. Humans are considered less susceptible than the herbivores'Carnivora may be infected, including domestic dogs and caEs, but Ehey

are quite resistant to Ehe disease, part.icularly dogs. Birds areinfrequently infected naturally and are infected with difficulty artifi-cially. RepCiles, amphibia, and fish may be infected if the body temP-

erature is mainEained at a high 1eve1. Guinea pigs and mice arecommonly used as experimental animals for anthrax and are highly sus-ceptible. Less than l0 sPores of a virulenE strain of B. a+thfaciscan cause death when injected into a mouse. ftaLs, particularly whiterats, are very resistant. to anthrax.(tt4'6)

The severity of the disease in animals is related to the naturalsusceptibility of the animal and the mode and 1evel of infecEion.Natural occurrence in animals results primarily from ingestion ofcontanrinaEed food. In endemic areas where food may easily become

contaninated, large numbers of animals may be infected. AbouE 50 cases

of anihrax in humans are reporCed annually in the United States'(I'3'19)Excepc in rare cases, these are cutaneous anthrax'

g. I"lortality/Sequel-ae. In the Uniced States, Ehe mortality ratefor reported .uTZiEiiiJi?Ections in humans prior to Ehe discovery ofantibl-otics was 20 Percent. Cutaneous anfhrax responds to treatmentwith antibiotics, and ihe moriality rate for promptly diagnosed and

treated cases is essentially zero. f- iratory

"l!!!=-js--es-s-e+Eial-1:-1-g9-!::-.Jlc. - n

anEhrx is uniikely, treiiment-;iih antibiotics is inef f ective - When._ : l--#

3-;

Based oa 1.235 animalsLD=I IM]-E S

41130 spores, with 95% confidenceof 1,980-8,630

Probit slope = 0.669 probits/1og dose,with 957" conf idencs lr'mi gs of 0. 520-0.818

99.9ooaoo <

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Figure 3-1 (U).

103

Dose (spores)

Response of CynomolgusB. Anrhragis(ar) (U)

104

Monkey to Aerosols of

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3- 10

i. i_ .f y _y:-."\:\ ' *: -r r ;

alat

c. (u) rarElcre ptze ano rnrecELvl-cY

(1) As illustrated in Figure 3-2r(za) lhe ma-imrrm lrrng roEenrf nnin humans occurs r,rith the inhal@ 2 microns in diameter.n affecte<i b

'and hygroscopicity of inhaled particles. The curves of Figure 3-1 portrayt@toti1upperrespiratory,anddeep-1ungdepositionversus particle size, at a breathing frequency of l-5 inhalations perrninute. The information in (a) through (e) be1ow is stnnmarized fromthese curves.

(a) The highest probability for deposition of inhaled particlesin the respiratory spaces of the lungs is in the size range from 1 to2 microns (graviEy serrlemenE) and the submicroscopic size below 0.2rnicron (precipitation by diffusion).

(b) Above L to 2 microns, penetration to and deposition in thelobules falLs off with increAsing size, because fewer particles escapeupper respiratory trapping. Above 10 microns, the probability forpenetration to the lobules is essentialLy zero.

(c) BeIcru 1 to 2 microns, lobular deposition falls off,because the efficiency of removaL by gravity settlement within thelobules Ehemselves decreases.

(d) The lowesE probability for deposition of inhaled particlesin the respiratory system is at 0.25 to 0.50 micron, where the combinedforces of precipitation by gravity and diffusion are at a minimum.

(e) The probabiLity of l-obular deposition increases as particlesize goes dovn (in conErast to gravitational setElement, which decreaseswith sizel . (aa)

(2) Monkeys often breath through their mouths resulting invaried and scattered particle retenEion in the lungs; aerosol particles4 to 6 microns in diameter Ehat would have been extensively crapped inthe upper respiratory tract e/ere Erapped in the lungs instead,.(7) Ifinfection can only be caused by spores in particl-es with a criticaldiameter of less than 2 microns, present methods of assessment may beindicating incorrect dose patterns. I'or several years, field test andchamber work for dose response has employed the preinpinger-impingercombinat:on for dose determination of particles 5.0 microns or less.Assuming a 50-percent cutoff of 5.O-micron particles by the preimpingerand a mai:imum spore population for parcicles of given aercsols, then

\

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DiameLer of Particle (microns)

Total and Regional DePosition ofRelation Eo Aerodlmamic Particle

Inhaled ParticlesSize (u;.rzs1

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k"* kuu

3-12

partic:es with an OID- of 5.0 rnicrons nay theoretically contain as many

as 75 spores per particle or as few as one. Cn the other hand, particleswith ar OID of 1.5 mlcr:on contain only one spore per particle. Dependingon rhe aerosol, this inciicates that when tl're cloud is assayed with thepreinpinger-impinge:: combination in series, dose response for Particles5.0 rricrons or less rnay vary for a given species by as much as 75, even

:-f equal infecting capaciCy ls assumeC for inhaleci particles fron 1.0to 5,C microns.(?)

IIIIIIIIIIIIIII

44 .O Storage

\\.,/ a. (U) General. Bacillus anthracis is one of the most resisrant oft'/lythe biological agents to deterioration in storage. Few data on the effect

//', of storage are available, because of the very long time required to observe

" t such effects. The viabiliEy half-1ife of the spores in storage has beeni estimateC to exceed 5 years at temperatures ranging from 4 to 39 oC.

4-)

e. (U) Accelerated Assessment of Storage Stability

(1) (U) Storage stability of both wet and dry B. anthracis wereevaluated using an acceLerated storage concept.(43)' Thfr .."."pt useC a

probit mccel to <ietermine the percent of agent recovery when the agent isstored at a constant temperature for given periods of time. In essence,the experi;aents consisted of placing agent sanrples) contained in glasstubes, in oil or ethylene-glycol baths (maintained at constant tempera-tures bei:seen 50 and 100 cC.) for 1 to 6.1 x lOa minutes. The data

/.4

,

IIItIIIIIIIIIII

-

(2) (U) Using the survival data at high temperatures and the model(Equation (4.3)), estimates of times to 50-percent survival were madefor storage temperatures. The reported(43) estirnates of 50-percentsurvival are 620 years and 165 years for wet and dry B-anthracis, res-pectively, stored at 3 oC. Using the mode1, SO-percent survival timeat roon temperature (27 aC.) was estimated to be 3 years and 4.5 yearsfor rvet and dry B. anthracis, respectively. For storage at 39 oC.,estirneted values were 12 r+eeks anC 43 weeks for wet and dry rnaterial,respectively. Although these estimated values indicate that B. anthracisspores can be stored. with relative ease for long perids, tn"y-ipp"l. E-underestimate survival, when compared with the results of a few storagetests. For example, it has been reported that wet B. anthracis sporeswere stored in a laboratory for 5 years without detectable loss in sporeviability, whereas the estimated value is a 5O-percent loss in 3 years.

f. (U) Estimates of Storage StabiliEyto obtain daca on loss of viabiiity of B.

. It appears toanthracis spores

be feasiblestored at

room temperature (27 oc.) by actual measurement over a reasonably extendeciperiod (5 to 10 years). Such data would be of value in assessing chelogistics burden for employing thi-s agenE cffe:rsively by an adversary.For the present, based on data in Table 4-3, it appears reasbnable toassune a half-life of at least 2 years for eiCher wet or dry agent storec

It nav be assuned that l-oss of viabilitv of B anihra cisdq-yonT e rr

^- o- CndL !-/ (,.

L-:

ie ^7'

I

,l

(5) (u)cvcling on drythe age:':.t andthaw c'.'c1ing 1

No data are availableB. anthrasis . Because

beiause it is i:ozen inike l-v ha s lit iie or no

on the effect of freeze-thawrrf the small moisture content ofthe Process of drYing, freeze-

e!fect on agent survival'

4-4.C DisseminaLion

a. (U) General. The dissemination component of the source model

describes the transformation of the biological agent (aqueous slurryor presized dry particles) into a viable, infective, inhalable aerosolc1olaofspecifiedstrengEh,size,and1ocation.@

ased on pff_enE*wfEh-a 3-: L- a genL --t-q :bgE s rlgr

b. (U) Source Strength

(1)f."- " r.t"t-** l:roma1it-g*rw".ry h"fTo..r -an instanLaneous diEseminaElon by an explosive d€y!q-q-o-E a-contin-uffii Ei: -ii-uT a f io.r1 -f .o* .i'

" " ro

" qf ffi.t "

t"- tn. -siu?cE-stienfEtr oT-"t6e.aerosol Cloud - that is, the number of sporescontained in Ehe cloud at its source - is a function of the quantityand concentration of the agent product in the disseminator and of thedissemination efficiency of the disseminator. IAerosol particles equalto or tess than 5 microns in diameter are considered optimum for

W e-E856fi-shing respira tory i€":!igrr-irr-*3rr,-l The dis-s em e fficiency

s tG si"" range.l

(2> The various models used to determine the source strengthof a munition are defined as follows:

(") The source strength model for a point source of wet ordry agent material is

rvher e

Q = VG.rd (4.5)

Q = .source strength, number of viable organisms in particleswith <5 microns ciiameter.

V = volume of agenc fill in Ehe munition.

G., = concentration cf viable organisms in Che agent fill at Cime' of muni:icn iurccioning.

4-L4

efficiency of the munition in converting agent fill into anaerosolized particle cloud of viable sPores; the ratio ofche number of viable spores aerosolized in Part.Lc1g9 with <5

'@lE d_i_es"_!_.-'_ !_-o_ -q[9-_t.tr&9l_ s! _y=ie.hle- -fggls!_l! lhe agentfill prior to functioning .

(4 .6)

(4.7)

I

I

I

I

I

III

!rII

4-L5

ffi

d=

+

where q = number of viable organisms in aerosol particles with <5

microns diameter, p€r unit of line length

E = agent emission rate

V = speed of disseminating delivery vehicle .

(b) A line of relativell' closely spaced point sources (bcmb-

lets or generators) may be Ereated as a line source when the effectsconsidered are at sufficient distance dorunwind for the individual pointsource clouds to merge.(4E) In Chis case, the source strength is

Errdq=-

II

Number of point so"rces x aq=@

This moiel is further discussed in Volume X.

(3) Methods of measuring source strength are described fu1ly inVolume VIII, Part One. In some discussions, source strength is definedas the number of organi"E_€Ig,q_9-9f thragent thE-t--;r,-e-b--ot-h--v'LablcaF ement of the agent in an aerosoltuC1oud,--wEen'employed as a weaPon, is thaE it be infective. However,the source strength of TR has been measured and expressed only as viablespores, and Chis definition of source sErength is used in this part ofthe Source Book.

c. I Dissemination Efficiencv

-

I

CHAPTER 7

I orru*ru (u)

The protective mask is the principle meansfrom infection by an aerosol of TR. EguationpresenCation of the functions associaced withprotective mask by a biological aerosoL:

of physical protection7.1 is a generalthe penetration of the

where d,

r1

dr = rlr,B(t) Ct

rePresents Ehe respiratory dose

is a paraneter represenEing theretained by the lungs

ls a parameter representing thea proEective mask

(7.1)

(organisms)

fraction of inhaled agent

fraction of agent Penetratingr

I

I

I

I

I

II

. (U) Physical ProtecEion

IIIIIII

r = 1.0a.

B(t) is breathing rate (,/nin)

C is concentration of airborne agenE (o.gl !,)

t is exposure time (min).

Volure X of the Source Book discusses chese respiratory urodels andparaneters in detail. As indicaEed in that volume, the reEentivityparameter is the only agenc-dependent parameter.

There are no data from which Eo estiloaEe Ehe retention of aerosolizedTRI and TR2 in the human 1ung. However, data are available to indicatethat 20 to 25 percenE of aerosol particles equal Eo 5 microns in dianeter

7-L

are retained in fhe human lungs after exPosure; a maximum of 45- to50-percent reEention occurs with particles 1 Eo 2 microns in diameter.(as)

7-3. (U) Biologieal Countermeasures

Countermeasures agains E

vaccinaEion, and supportiveB. anthracis infectionclinical procedures.

include chemotherapy,

a. Chemotherapv

(1) Effective chemotherapeuEic treatmenE of pulmonary anchraxin humans is possible if diagnosis of the disease is made early enough.If anthrax is suspected, creatmenE shouLd be initiated prompEly wiEhoutwaiting for laboratory diagnostic test results.(8r?o) Drugs must beadministered during a definite stage in the disease before the onset ofEoxemia. Beyond this critical point, the sepLicemia wiLl resulE intoxin-induced deaEh, regardLess of anEimicrobial chemotherapy.( a rlo)

(2) B. anthracis is susceptible to the action of penicillin andthe tetracyclinesr- and these drugs have been effective in EreaEingcutaneous anEhrax.(3rru) Tetracyclines are less effective than penicillin.Table 7-1 presents the reconmrended drug doses for effeccive treatmentof anthrax. The use of penicillin or the tetracyclines in humans aschemotherapeutic agents for preventing inhatation anthrax or foraborting anthrax infection following aerosol exposure has not beenassessed. However, prompt treaEment of exposed individuals wouldpresumably reduce infecEion and clinical disease raEes.

Antiserum

(1) Antibodies are effectiveanthrax. They are not effecEive inof B. anthracis, i.e., the toxin(s)large amounts during Ehe septicemic

against the causative organism ofneutralizing the metabolic productswhich is produced in the host insEage of the disease.(s)

(2) A specific antiserum must be empl-oyed to neutralize toxinsassociaced wifh anthrax. AnEiserum treatment prevented death inmonkeys which had been given a normally fatal dose of anthrax toxineither intravenously or by aerosol. A1so, \"/hen treatmenc was initiacedafEer the septicemic stage of anthrax was reached, significanEly moreanimals survived with combination antibiotic and anEiserum treatmentthan rvith antibiotic Eherapy a1one.(5,'to ) AnEitoxin, in conjunction withbactericidal antibiotics such as penicillin, is recornmended. ( l 8) ForanEhrax in tne septicemic stage, the dosage of antitoxin serum should belarge "...40 ml intravenously, this amount being repeaEed several timesa day. Urgerc cases have sometimes been given 100 co 300 ml inEramuscu-larly and inEravenously daily f or f ive da;rs. rr( " I ) Th. serum is non-standard and is derived from inrnunized

7-2

TTNCLASSIFIED

horses. Severe serum reaction may occur, prolonging morbidity'(ztlAntiserum is no longer available cosrnercially in the United SCates'(8It appears thaE the Russians use antisera in the medical treafment ofanthrax. Also, the Russians use a varieEy of drugs that would be

expected to stimulate the cardiovascular system'( I8)

"o),'

Table 7-1 (U) Reconrnended Chemotherapy Regimens for AnEhra{3,1o t"o)

LengthDrug

Penicillin G

PENICTIIIN U

S trep EomycinbTe tracyc 1 ine s

Treaofnt

7-14 days24 hours7 days7 days

aBeginning at onset of disease (suspected or diagnosed).rstieptomycin and penicillin gdministered concomicantly have

synergisiic effects on anEhrax disease of rhesus monkeys.(e) Such

efficacy remains Eo be demonstraEed in humans'

c. Supportive Clinical Procedures

(1) Experimental use of isoproterenol (1-(3,4-dihydroxyphenol) -2-isopropylarninoethanol) in rhesus monkeys resulted in Eheir survivingthe effecls of anthrax toxin. Its action may be attributable todilation of the pulmonary vasculature, which would a1low uninterruptedflow of blood through the vascular system of the lungs' or to Lhe known

action of isoproterenol on the nryocardium, which causes an increasedcardiac outpuc. One or both of these effects could maintain orreestablish che function of the central nervous sysEem' especially the

respiratory center, by increasing circulation and oxygenation'( t") The

effecEiveness of using isoproterenol against anEhrax in humans has notbeen reported Ehus far.

(2)Supportivetreatmentdirectedtowardmaintainingcirculationand fluid-eiectrolyle balance also requires special attention during the

critical phase of anthrax disease '(25 '7o) This balance has been maintainedin monkeys and found to be effective in preventing death. In addition'since the orygen level of che blood is decreased by toxins during the

course of the disease, ox)'gen administration is probably helpful'Survi.ral of anrhrax-infected rhesus uronkeys was maintained by the use

o f a posici'/e-Pressure resoi rator'( 5 ,1 ")

12

Route ofAdminis tra

Daily Dose'

600,000 units I tncramuscular20,000,000 units I Intravenous1 to 2 grams I fntramuscular2 grams I tntramuscular

U}{CTASSIFIED

(3)exPe rimen Ea1

seems to beare presentshock, alsoresponse to

UNCLASSIFTED

Blood calcium and glucose levels decline before death inanimals. Therefore, adrninistration of calcium gluconate

desirable. Steroids, administered after the bacteria thathave been controlled by antibiotics or after symptoms ofappear to be beneficial in reducing clinical symptomaticthe disease. (6 )

d. Inrmunitv

(1) It has been hypothesized that workers in factories handlingconEaminated hides or wool develop a natural iurnuniLy to anthrax as aresult of a subclinical infection derived by exposure to a continuouslycontaminaEed environment. This has been presumed because the greatestnumber of cases of industrial anthrax have been observed in first-yearemployees. However, in evaluating the occurrence of anthrax amongworkers in contaminated industrial plants, Brackman, et a1.r('tz)concluded thaE vrorkers did not develop subclinical infection or inrnunityresulting from long exposure. They calculaced an atEack rate, based onincidence of disease and years of work, which rvas sl ightly buE notsignificancly greater fcr l- to 4-year employees than for 17- to 2O-yearemployees. The greater number of cases among shorE-Eime r.rorkers resultedfrom the significanEly greater number of employees in thaE category.Irnmunity apparently is acguired with sublechal clinical infecEion, asdemonstraEed by irmnunogenic response.('7o , '73)

(2) Ilost of the recent inununological work in the United Scatesrelated io B. anthracis has consisted of improvemenE of che protecEiveantigen preparation for in'rnunizaEion of humans, clarification of cherelaEionship between the proEective antigen and other components of theanthrax toxin, and investigation of the effects of innnuniEy on infectionand disease.(s)

(3) T\^ro human field studies of inhalaEion anthrax using Wright'svaccine nave been reported.("c,'71) Wrightrs vaccine is produced fromthe R1-N? strain of anthrax. RI-NP is a noncapsulaEed, nonproteolyticmutant oi the Vollum strain of B. anthracis. The protective antigen\ras precipicated and concentrated by adding 0.l-percent aluminumpotassiu:r sulfate (alum) and was standardized against rabbits.(zs) Theintracu:aneous LD.n of the preparation for rabbics r,/as approximately 100spores.(-+) This vaccine was an effective inrnunizing agent forLaboraEc:y animals.(7s) It was well tolerated in a EesC in wirichapproxi:.ate1)r 700 humans received more than ?,000 injections of theprepara:i6rr.(24)

One study involved r+orie:s engaged in manufacturing coaEinterli::ings from imporred goai hair conEaminated by B. anEhracis.Enpi-oyees'..rho had recovereci from anflirax \nere excluded froin :he Eesc.('o)

T]NCLASSIFTED

1t l-; a;ilrt-El,il8

TINCLASSIFIED

Two groups of volunceers were used. The same vaccination schedule wasemployed for both groups. One group received a placebo of 0.l-percenca1um, and che other received Wrighc's vaccine. The iniEial seriesconsisted of three 0.5-cubic-centimeter subcuEaneous injecEions, eachgiven at intervals of 2 weeks; Ehese vrere followed by three boosterdoses of 0.5 cubic centimeter, which were given every 6 months; then 0.5cubic cenCimeEer was given annually.(22) Forty-seven percent of a coEaleligible Eest population of 11249 people worked in high risk areas ofa mill (spinning or carding of the raw wool), and 53 percent worked inlow rlsk areas (weaving and finishing of interlining material).("o)DaEa were sEaEistically analyzed for inrnunized high- and low-risk groups.The attack rate in the placebo or conLrol group was calculated per 1r000person-spnths. Based on this rate, the total expected cases of anthraxfor Ehe tesE or vaccinated group lras estimated to be 13.35. Since onlyone case occurred, the vaccine appeared Eo be 92.5-percentseffeccive.The Lower 95-percent confidence limit for effectiveness of the vaccinewas calculated to be 65 percent.(7o) The human experimentation resultssuggesLed that three consecuEive doses of the vaccine are reguired aspart of the initial immunization regimen. One or trwo doses, administered3 months after the primary series, seenred advisable for adequate andconEinued protection.( 7o

(5) A second iumunization program v/as conducced with humanvolunteers. Three subcuEaneous inoculations of 0.5 cubic cenEimeterof Wrighcrs anEigen were adminisEered at 2-week intervals. A boosterdose of 0.25 cubic centimeter lras given 6 months after the initialseries. In 660 individuals who received Ehese inrnunization regimes,no significant syscemic or 1ocal reactions were observed.(z+) However,no data are available relaEing to the degree of procection affordedthese volunEeers by che vaccine against anthrax infection.(7a)

(6) A number of live vaccines have been developed for anthrax,the first by Pasceur. I'{osE of these vaccines have been relativelyreactogenic, and their use has been linited primarily to livestock.The Russians have developed teTo sErains of B. anthracis for use as livevaccines, the STI and the (Sh)-15 sErains, and Ehese have been usedagainst l-ivestock.(5) The STI strain has also been used in the USSR forinmuniza!ion of humans by subcutaneous, dermal, and aerogenic methods.(75)Dry material was used in aerogenic inrnunization. Aerogenic inrnunizationwas reported to be least reactogenic and was as inununogenic as fhesubcucaneous injection and more irmnunogenic than the skin method.("5)Vaccinations are routinely given to individuals employed in tanneriesand meat-packing plants or to people living in areas where anthrax isendemic. Vaccination with ST1 is reconunended at intervals oi 10 months.(zz

( 7) AnEhrax irununi ty is nore cotrplex chan other irnrnunitieswhere serurn antibody tlter leve1 is considered a neasure of the levelof i;rrnu:::Ey. The naEure of the anthrax antigens and the stage of the

7-5

t]NCIASSIFIED

I}NCLASSIFTED

disease affecced by a particular antigen musc be considered.(za) Toprovide maximal inrmunity against anthrax infection, antibodies againstspores) vegetative ce11s, and toxin may be required. The immunogenicityof components of anthrax toxin has been studied. These components havebeen described as the edemic factor (EF), protective antigen (PA), andEhe lethal factor (LF); as nentioned previously (par. 3-3e(5)), theyare noE individually toxic, Studies have shown thaE the LI componentwas irrnunogenic for the rat and the guinea pig against spore challengeand for the rat against toxic challenge.(?erao) (Although the raE haslow susceptibility to infection, it is highly susceptible to toxininjection.) Inurunity of the rat to spore challenge was increased whenPA was included with LF in inmunization. Inrnunity to Eoxin challenge didnot irnprove. PA, as weLl as LF, inrnunized the guinea pig against sporechallenge, and the conponents vrere complimentary. The variation inresults between animals enphasizes the problem of developing effectivehuman anthrax vaccines derived from toxin antigens. However, it appearsthat the LF and PA cornponents eould now be developed as a vaccine againstanthrax in humans. Another problem raised by inrnunization, particularlyagainst the spores or vegetative cells, is the potential for 1ow-leve1infection Ehat would now be detectabLe through observation of bl-oodsanples, but would al1ow accumulation of toxin to a critical 1evel.There is no basis to predict whether or not this phenomenon should beobserved in humans.(eo)

7-4. I o""oniamination

a. (U) Di:;[er€]!.rces in {gqnt Forms

(i) VegeEative ce1ls of anthrax are to some degree resistantto deleterious effects of environment; however, in Che spore form, thiorganism is verl resistant to environmenEal effects.(3 rs) Spores rqi11not germinate to form infecCious vegeCatiwe bacte.4ial--Cells- u,qJg_s-_s

exposed to air for several hours at 68 oi_r_(ZQ_"gJ___at a relativghumidity equal co or greaEer than 65 percent.

-T1

Itt',,id

!'!

i

Tii

I

{

*

(2) To insure effective decontamination,spores is reguired. A summary of the resistanceenvironmental or other decontaminating agents is

(a)

deactivation of cheof B. anchracis toas follows:(3,1e)

Vegetative cells:

Are ki11ed in slurry by heating aE 65 oC fot 30 minutes

Are readily destroyed by disinfectanEs, such as 1ysol,betapropiolactone, or aliohol

A:e kilied by heaeing aE 55 cC. for t hour, or severalmirutes a. temperatures above 70 "C,

7-6

I,INCIS,SSIFIED

(b) Spores:

Generally are ki1led

Generally are killedfor 3 hours

boiling for 1O minutes

exposure to dry heat at 140 oC.

vapor of betapropiolacEone16 hours, respectively, atand a relative humidity above

by

by

Are kil1ed by exposure toor formaldehyde for 2 anda Eeuperature above 70 oF.70 percent

&!;I

I

I

I

IIIIIII

Are resistanc to drying effects of environmenc and canremain viable for 10 years or nrore

Disappear rapidll' from unprotected soil surface whenexposed to direct sunlight for a 2-day period

Survive for long periods under proCection of soils,in animals hided and carcasses, and followingaero so 1iz ation

Are able to survive for long periods at cryogenicterperatures (-120 oC.); are also resistant co rapidfreezing (-78 oC.; and thawing (37 oC.) procedures.

(3) Irradiation of spores dried on glass (e.g., window glass)trith ultraviolet at an 18- co 20-vo1t intensity (simulates a clear day)for 45 minutes produced an 89-percent reduction in spore viability;irradiation at a'16- to 2l-volc inEensicy (natural sunlighc) for 45minutes reduced spore viabilit;l by 67 percent; with a 60-minute exposure,the reduction was 95 percenE. Vegetative cells can withstand shortexposure to ultraviolet (75 sec.).(ee)

7-7

(2) (Lt) ZLrLa, etal.,(Bs) in an analysis conducted for the U.S.Air Force, iodicate that betapropiolactone (BpL) is effective indecontaminating surfaces conLaminated with spores of B. subtilis andchat it is the least corrosive area decontaminant pre"EnEty-Z"aTlable.Requirements for speciaLLzed decontamination of equipment and surfacescontaminated with microorganisms or toxins led to the investigation offormaldehyde gas released from dry paraformaldehyde as a decontaminanL.(e6)The sterili-zi-ag effectiveness of fcrmaldehyde gas produced by depoly-merization of dry paraformaldehyde i.s given in Table 7-3. Valuespresented for B. subcilis apply to spores of that organism and areapplicable to spores of B. anthracis, inasmuch as the spores of B.anthracis are less resistant tnan spores of B. subtilis. SterillTarionoccurred after depolymerization of 0.3 gram .f p"r"f.r-aldehyde percubic foot o: space for a l-hour contact period. The range of use fordry paraformal-dehyde is rated equal to that of formalin. Test resultsindicate that the dry gas produceC by depolymerizaEion of paraformaldehydemay be a more effective sterilizing agent than vaporLzed formalin. Thisgas also disseminates irore readill'and is more rapidly dissipated byaeration. Formalin (37-percent forrnaldehyde in water) was rated equallyas effective as BPL, but the requirement of a longer contact time forthe formalin nakes it less desirabl"e. (85) Ethylene oxide vapor is somewhacless effective than either BPL or formalin, but it is a useful decontaminantunder certain circumstances. However, ethvlene oxide was one of the mosEcorrosive of the decontami-nants tested on Air Force materiel.(Es) Table7-4 contaios some pertinent information relating to the cited decontaminanCs.

;- t0

r-I

! lG3:r-t:i$**t.:_ *qd&*|l:btd. Itul,l!tu'.-r@E.

Table 7-3 (U), Formaldehyde Gas SLerillzatlon of Facilities, MaCerials, and Equlpment

{I

HH

"Nunrber of viablebCoucentration of

recoverles per total tests conducted106 per paLch.

TesI(lrlnrli t i ou

Vo lume(crrblc fecL)

Anount ofParaforrnaldehyde

(em)Organl srns

Conc ent ra t lon(per m/)

Viab I eRecoverlesa

T.,aboratory rooms

La rge roorn

Iloblle laboratory

Surfaces

Iri l rcr rncdia inclass I cabincL

Laboratoryc <lul pmen t

Vacclne tubcs

22504s9B

67 2L6

2200

25

42

100- 200

685L379

20t65

330

7.s

12,6

30- 150

0.6

subtilismarces cens

srrbtllis

sr-rbtili-s

subEllis

subtills

B. subtilis

B. subcillsS. narcescens

1061010

106

106

10?

b106

106

104104

0/s0/s

0/L

0/s

0/s

0/s

0/ 10

0/20/2

.t'rble 7 -/+ (1:) Characteristics of Selected Decontaminants(85)

Decontaminant Physical Statefor Use

n'i;rI:!

{

!:

I'

i

I

$

Betapropiolacione( nPi,)

Formalin (37%formaldehyde inwat er)

Ethylene oxid.e

EnvironmentalLimi t at ions

RH not less than7O%: minimumeffect ivetemperature24 oC. (75 oF.)

RH 857. opEimum;Eemperature 2l-27 oC. (70-S0"tr'. ) (not lessthan l-6 oC.

(60 oF.))

Minimum effectivetemperature16 cC. (60 oF.)

Decontami nantRequirements

Vapor oraerosol

Vapor oraero so 1

Vapor

2-hour contacttime;24-houraerat ion

16-hour contacttime;24-houraerat io n

6-8 hourcontact time at2L ac. (70 or.);12-hour contacttime at 16 oC.

(60 or. );12-hour aeraEion

7 -L2

IIIIIIIIIIII\

(5) (U) Findings coocerning the effectiveness of BPL in reducingor eliminating the contamination wilhin the ship are noE included in thecited report.(87) The data'wera far too variable to give explicitresults; horvever, the data showed that contamination was nateriallydecrea s ed .

(6) (U) fhough BPL was found to be an effective and relativelynon-corrosive decontaminant, ils use as a decontaminAnL has been negatedby a ruiing of rhe Public lleal-th Service prohibiting Ehe transport ofBpL in interstaEe cortrnerce. This order was instituted because of thetoxiciE)' and report,ed carcinogenicity of the compound.

e. (U) Decontarnination of Small Articles. Because of the inabilityof BPL to extensively penetraEe hard-to-reach.spaces, convoluted materialscannot be decontaminated using Ehis agent. ( u- I Ethylene oxide can beused to decont,aminate srnall ieems (books, too1s, etc.) by placing thecontarninated articles in sealed plastic bags and releasing ethyleneoxide (usually in an aerosol can) within the bag.(ee) As indicaEed inTable 7-4, 6 to LZ hours of contact, dbpending on temperature, shouldadequat.ell' eliminate Ehe hazard. Echylene oxide has beeq used Eo

sCerilize laboratory equipmenE or cloEhing using Ehe gas in an autoclave,a sEeel drum, or polyeEhylene bags(48'8e) MaEerials heavily contaminatedwith resistaot spores will require an exposure of 300 to 500 milligramsof eth;rlene oxide per liter of air for about 6 hours at 25 aC. to destroyche bacil1i. Some moisture must be present to adequaEely compleEe theprocess of decontamination.(3e) No changes io the external appearance

of the articles (mi1itary uniforms, shoes, etc.) were noted afterexposure of 4 to 10 hours at a concentration of 20 to 30 grarns ofethylene oxide per kilogram. B. anthracis spores were inoculated intocloth treated with various chernicals, including permaseptic and chlorinein an assort.menE of solvents. delorine in acetone tetrachloride wasquice effective in rendering Ehe cloth unsuitable for organism survival.In aooLher experiment, boiling for 15 minutes rid the cloth of spores.(68)Soaking contaminated clothing in a 10-percent formaldehyde solution iseffective.(6) Autoclaving at LzL oC. for 15 minuLes is a reliabletreatment for kiLling spores on cloth or other small articles, but theefficiency of this method depends on the complete heat penetration ofbulky material.(s) Polyadov, eE a1.,("o) suggested the use of nitrogendioxide as a bactericide against both the vegetative and spore forms ofB. anthracis. The high mobility, penetrating po!/er, absorptivity, and6Ch-:contact properties of gas molecules gives- gaseous bacteriocides anadvantage over liquid and powder disinfectants. Nitrogen dioxide (NOe)is a powerful oxidizer. Tests have shor'rn that NO, at a concentrationof 0.5 gram per liter of air killed the vegetaLive forrq of B. anthracisin2Eo3minutesandsporeformsin5to].Ominutes.rt'esGffimade at room Eemperature and normal atmospheric pressure. Nitrogendioxide should be tested as a disinfectant of different objects inenclosed premises, as well as of buildings infected with anthrax sporer.('o)

7-L4