This research was supported by grant NSH-2 104 from theNational Aeronautics and Space Administration, by grantDPP 75-19437 and logistics grant DPP 76-19827 from theNational Science Foundation, and by grant AI-10404 fromthe U.S. Public Health Service - National Institutes ofHealth.

References

Allen, T.R. 1973. Common cold epidemiology in Antarctica. In:Polar Human Biology. Edited by O.G. Edholm and E.K.E.Gunderson. William Heinemann Medical Books, Ltd., U.K. p.123-124.

Cooney, M.K. and G.E. Kenny. 1977. Demonstration of dualrhinovirus infection in humans by isolation of different serotypes

in human heteroploid (HeLa) and human diploid fibroblast cellcultures.Journal of Clinical Microbiology, 5: 202-207.

Fox, J . P. 1976. Is a rhinovirus vaccine possible? A mericanjournal ofEpidemiology, 103: 345-354.

Holmes, J .J . , T.R. Allen, A.F. Bradburne, and E.J. Stott. 1971.Studies of respiratory viruses in personnel at an antarctic base.Journal of Hygiene, Cambridge, 69: 187-199.

Minor, TE., J.W. Baker, E.C. Dick, A.N. DeMeo, J .J . Ouellette,M. Cohen, and C.E. Reed. 1974. Greater frequency of viralrespiratory infections in a sthmatic children as compared withtheir nonasthmatic sibiings.Journal of Pediatrics, 85: 472-477.

Parkinson, A., H.G. Muchmore, L.V. Scott, J.A.R. Miles and E.C.Dick. 1976. Enhancement of virus isolations by utilizing tissuecultures in the field. AntarcticJournal of the U. S., XI(2): 68-70.

Tyrrell, D.A.J. and M. L. Bynoe. 1966. Cultivation of viruses from ahigh proportion of patients with colds. Lancet, 1: 76.

Lack of increased susceptibilityto colds in the McMurdo winter

parties of 1975 and 1976

ELI.Ior C. DICK', RICHARD S. JERDE',DAVID M. WARSHAUER', ADRIAN D. MANDEI,2LAWRENCE W. Fuscii 3 , DANIEL, L. TULLIUS4,

and HAROLD G. MUCHMORE4

'Depart ni en t of Preventive MedicineUniversity of Wisconsin, Madison

Madison, Wisconsin 53706

2 A nies Research CenterNational A eronautics and Space A dminisl ration

Moffett Field, California 94035

3 Naval Support Force, A iila ret icaConstruction Battalion Center

Port Hueneme, California 93043

4 Department of MedicineUniversity of Oklahoma Health Sciences Center

Oklahoma City, Oklahoma 73190

Several studies have suggested that when normal popula-tions are placed in isolation for several months, they may besubject to respiratory disease of increased severit y when ex-posed to infectious agents either during the isolation periodor upon return to civilization (Paul and Freese. 1933:Holmes, 1973: Holmes and Allen, 1973: Allen, 1973). Thisconcept of increased susceptibility to infection after pro-longed isolation has been cited in popular antarcticliterature (Dukert, 1965) and is firml y held b' the great ma-

jority of persons with whom the authors have associated dur-ing their antarctic investigations.

A unique circumstance where amount and severity of res-piratory disease in a previously isolated population can becompared simultaneously with that in a normal populationoccurs during the winter fly-in (wINFLY*) period at McMur-do Station, Antarctica. Early in September a detachment ofmen (146 men in 1975, 135 men in 1976) is flown from theUnited States to McMurdo to help ready the station for theaustral summer research season. These WINFLY men join agroup that has been isolated since mid-February (winterparty: 52 in 1975, 65 in 1976). There are no additional ar-rivals until the summer season opens early in October;therefore, for about 5 weeks no infectious agents circulate atMcMurdo other than those brought in by WINFLY personnel.

The housing, messing, and recreational facilities areshared by the WINFI.Y and overwintering groups, and thegreat majority of men eat at the communal mess hall in theprimary berthing facility (building 155).

At the outset of WINFLY 1975 and 1976, some of theauthors (E.C.D. and D.L.T. in 1975; E.C.D., A.D.M., andR.S.J. in 1976) accompanied the WINFLY party to McMurdoand assayed the amount and severity of respiratory infec-tions in both the WINFLY and winter groups. Surveillancewas by daily interviews in the communal mess line and bvisits to personnel in semi-isolated locations. Numericalresponses were recorded on a standard form descriptive ofsigns and symptoms of respiratory infection (D'Alessio et al.,1976).

The number of colds present irs the wintering WINFLYpopulations during the two %VINFL\ periods is presented intable 1. In 1975 there was a slightly higher incidence of coldsin the \VINFL\ group: however, this trend was reversed in

*Used both to designate persons coming to McMurdo at the outset ofthe winter fl y -in period as well as to designate the period itself.

October 1977

1976. When the data from the two years were combined, theaverage incidence was nearly identical for the two popula-tions. Thus there appeared to be no differential susceptibili-ty between the winter and the WINFLY populations withrespect to susceptibility to colds.

The severity and duration of illness in the two groups wasalso measured (table 2). The average symptom score for theday on which symptoms peaked, the average score over theduration of the illness, and average duration of the colds areshown. As points of reference, severe colds yield point scoresof 12 to 18, while mild colds have scores of about 4. Therewas no apparent difference between the severity of colds onarrival and of colds developing during WINFLY; nor wasthere a difference observed between severity of colds inWINFLY and winter personnel. The same conclusions appearto hold with respect to duration of a single episode ofrespiratory illness.

We conclude from these investigations that the WINFLY

and the winter-over personnel had similar numbers of coldsof approximately equal severity. The long isolation period ofthe winter men did not appear to make them especially sus-ceptible to respiratory infection.

This research was supported by grant NSH-2104 from theNational Aeronautics and Space Administration, by grantDPP 7519437 and logistics grant DPP 7619827 from theNational Science Foundation, and by grant AI-10404 fromthe U.S. Public Health Service - National Institutes ofHealth.

References

Allen, T.R. 1973. Common cold epidemiology in Antarctica. In:Polar Human Biology. Edited by O.G. Edholm and E.K.E.

Table 1. Colds in winter and winfly personnel, McMurdo Station, Winfly (WF) period,* 3 September to9 October 1975 and 30 August to 6 October 1976.

Group Number of personsTotalWith colds atWith coldsWith 2With 3Incidencet

beginning ofduringcoldscoldsof coldsWF WF during WF

34(24%)77(53%)25(17%)00 25(48%)6(12%)0

21(15%)36(26%)4(3%)1(0.8%)2(3%)24(37%)6(9%)1(1.5%)

1975WINFLY 146

Winter 52

1976WIN FLY 135

Winter 65

6960

3148

Totals: for 1975 & 1976

WINFI.Y 28155(20%)113(40%)29(10%)1(0.3%) 51

Winter 117 2(2%)49(42%)12(10%)1(0.8%) 53

*No one entered or left McMurdo Station during the WINFLY period.tNumber of colds divided by number of persons.

Table 2. Severity of colds in winter and Winfly personnel, McMurdo Station, Winfly (WF)period,* 3 September to 9 October 1975 and 30 August to 6 October 1976.

AverageNo. ofpeak

YearGroupcoldsscore

1975WINFLY 346.6Colds Winter 0onarrival1976WINFLY 219.4

Winter 28.5

1975WINFL\ 1026.4Colds Winter 317.4during%INF1.\ 1976WINFLY 427.1

period Winter 317.3

*No one entered or left McMurdo Station during the WINFI.Y period.

Averageduration

Averageof coldsscore

4-7

12.2

5.1 8.9

8.0 15.0

4.8 6.6

5.4 5.6

4.8 6.8

5.2

6.6

4 ANTARCTIC JOURNAL

Gunderson. William Heinemann Medical Books, Ltd.. U.K. p.123-124.

D'Alessjo, D.J., J.A. Peterson, C.R. Dick, and E.G. Dick. 1976.Transmission of experimental rhinovirus colds in volunteer mar-ried couples.Journal of Infectious Diseases, 133: 28-36.

Dukert, J.M. 1965. This Is Antarctica. Coward, McCann, andGeoghegan, New York. p. 169-170.

Holmes, M.J., and T.R. Allen. 1973. Viral respiratory diseases inisolated communities: a review. British Antarctic Survey.Bulletin, 35: 23-31,

Holmes, M.J. 1973. Respiratory virus disease in the Antarctic: im-munologic studies. In.- Polar Human BioIog. Edited by O.G.Edholm and E.K.E. Gunderson. William Heinemann MedicalBooks, Ltd., U.K. p. 125-134.

Paul, J.H., and H.L. Freese. 1933. An epidemiological andbacteriological study of the "common cold" in an isolated.arcticcommunity (Spitsbergen). American Journal of Hygiene, 17:517-535.

Colds and immunity in the 77winter personnel at McMurdoStation and Scott Base, 1976

TIMOTHY C. FLYNN', LAWRENCE W. FUSCI-I', andELLIOT C. DICK'

'Naval Support Force, A ntarcticaConstruction Battalion Center

Port Hueneme, California 93043

'Department of Preventive MedicineUniversity of Wisconsin, Madison

Madison, Wisconsin 53706

Many studies have been done on relatively small popula-tions suddenly placed in isolation for several months. Aparameter that has been relatively intensively investigated isthe incidence and prevalence of mild respiratory disease inthese populations over the period of isolation (Cameron andMoore, 1968; Holmes etal,, 1971; Holmes and Allen, 1973).Many of these clinical studies have been accompanied bylaboratory investigations of immune competency asmeasured by changes in immunoglobulin concentration orthe peripheral white blood cell count (Muchmore et al.,1970; Muchmore et al., 1973; Ventsenostsev, 1973). Ingeneral, these investigations have shown that respiratorydisease dies out in the isolated population within a few weeksand that immunity may decline.

The 1976 McMurdo wintering party consisted of 60 U.S.Navy personnel, five U.S. civilians, and one exchange scien-tist from the U.S.S.R. Eleven New Zealand civilianswintered at Scott Base. Isolation began 14 February andended 30 August 1976. Approximately one-half of the Navypersonnel lived in single or double rooms in a large centrally

heated building, and the remainder lived in relatively near-by buildings, also with single or double accommodations.All buildings at McMurdo Station were centrally heatedwith forced air, except the power plant which had spaceheaters. Scott Base personnel all lived in a single building.Most of the men at McMurdo consumed their meals in thegalley of the primary berthing facility, although a fewmessed in other living quarters; Scott Base personnel ate inthe same building in which they were housed. Social con-tacts between personnel at McMurdo and Scott Base werefrequent, either in the service clubs or at the nightly movie.

The presence of respiratory illness was determined inabout one-fourth of the men by a daily sheet on which theyrecorded the presence and severity of respiratory symptoms(D'Alessio et al., 1976). Disease in the remaining personnelwas detected by regular interviews with the medical officer(T.C.F.).

Thirty-eight men volunteered for monthly blood collec-tions from which quantitative white blood cell determina-tions and differential counts were made. At the time of col-lection, the blood serums were frozen to await im-munoglobulin analysis at the University of Wisconsin,Madison.

Respiratory disease did not die out during the winterPeriod. Twenty-one individuals had 35 colds, with the peaknumber occurring in June. Symptomatic persons were pres-ent nearly every day throughout the isolation, althoughthere was a sharp decline in colds in August. The colds weremild; only eight colds were rated as moderate, and onlythree men were sufficiently ill with respiratory disease toseek medical attention at sick call. Nearly one-half of allcolds (14 cases) occurred in the eight men living in the space-heated power plant.

No decline in potential immunocompetence was noted inthe parameters measured. Mean monthly white blood cellcounts for winter personnel remained essentially constantover the period of isolation, and the differential count didnot change appreciably. Also, the serum levels for im-munoglobulins A, M, and G remained relatively unchangedthroughout the isolation period and within normal limits.

In conclusion, it does not appear that this population of77 men living under conditions of isolation exhibited the ex-pected obliteration of colds, nor did their immune com-petence appear to suffer as determined by white counts orserum immunoglobulin levels. Whether these findingsrepresent a unique circumstance at McMurdo Station in1976 will have to await confirmation. Any confirmatorystudy should be accompanied by thorough microbiologicstudy of the individuals to establish the etiology of the ap-parent respiratory infections that occur over the isolationperiod.

The authors are grateful to the naval and civilian person-nel who lived at McMurdo Station, Antarctica, during theaustral winter of 1976 for their active collaboration undertrying circumstances. We also are grateful to Eugene W.Van Reeth and Claude H. Nordhill, commanding officers ofU.S. Navy Task Force 199, for their unstinting encourage-ment of this research.

This research was supported in part by logistics grantDPP 76-19827 and contract DPP 77-06064 from the Na-tional Science Foundation and grant NSH-2104 from theNational Aeronautics and Space Administration.

October 1977