Emerging Infectious Diseases
[Volume 6 No.2 / March - April 2000]

Letters

Preventing Zoonotic Diseases in Immunocompromised Persons:
The Role of Physicians and Veterinarians

To the Editor: We read with great interest the article by Grant and
Olsen on the role of physicians and veterinarians in preventing
zoonotic diseases in immunocompromised persons (1) and the
letter by Barton et al. on the risk of pregnant women and young
infants for petassociated illnesses (2). Essentially all aspects and
conclusions of the study by Grant and Olsen are also valid in
Europe.

In Austria, veterinarians are well educated in zoonotic infections.
However, it is impossible for practitioners to know all zoonotic
agents in detail. In addition to immunocompromised persons,
pregnant women, and young infants, persons in certain occupations
are at higher risk for zoonotic infections. Veterinarians are one of
these groups. We have completed seroepidemiologic studies
involving veterinarians (3) and are testing other groups at high risk,
such as slaughterhouse workers, farmers, and zoo employees. We
surveyed 52% of the veterinarians in an Austrian federal state who
agreed to participate in the study. They completed a questionnaire
and provided case histories so that risk factors could be assessed.
We also obtained blood samples. The sera were tested for
antibodies to viral, bacterial, and parasitic zoonotic agents. After
correlating the serologic results with the statements in the
questionnaire, a statistical analysis, and another questionnaire of
selected participants, we found transmission of zoonotic agents
from animals to veterinarians for influenza A virus H1N1
(prevalence of the infection was much higher among veterinarians
than in the general population; a significant number of seropositive
veterinarians were swine practitioners [chi-square = p xx < .01]);
Coxiella burnetii (veterinarians who removed bovine placenta
without gloves had a higher risk [chi-square = p xxx < .001] of
acquiring Coxiella burnetii infections); Brucella sp.; Chlamydia
psittaci; Leptospira sp.; Toxoplasma gondii; and Toxocara
canis/cati (antibody prevalence was 20 times higher among
veterinarians than in the general Austrian population). As a result
of the survey, veterinarians know about their profession- specific
risk factors and take adequate measures to prevent infections; also,
they are more qualified to advise pet owners and persons of other
professions at high risk.

In addition to the pathogens listed by Grant and Olsen and the
agents listed in this letter, some other zoonotic agents present (at
least in Central Europe) are cowpox (mainly acquired from cats; 4-
6) and parapox viruses, lymphocytic choriomeningitis virus,
Newcastle disease virus, Erysipelothrix rhusiopathiae, and
Capillaria hepatica (7). On the other hand, animals are not the
source of human disease such as leukemia; there is no evidence
that feline leukemia virus and feline immunodeficiency virus, for
example, are transmitted to humans (8). The risk of acquiring a
zoonotic infection from a pet animal is definitely lower than the
emotional and health benefits of pet ownership.

Norbert Nowotny* and Armin Deutz
*Institute of Virology, University of Veterinary Sciences, Vienna,
Austria; and Animal Health Service, Styrian Provincial
Government, Department of Veterinary Affairs, Graz, Austria

References

1. Grant S, Olsen CW. Preventing zoonotic diseases in
immunocompromised persons: the role of physicians and
veterinarians. Emerg Infect Dis 1999;5:159-63.
2. Barton LL, Villar RG, Connick M. Pet-associated zoonoses.
Emerg Infect Dis 1999;5:598.
3. Nowotny N, Deutz A, Fuchs K, Schuller W, Hinterdorfer F,
Auer H, et al. Prevalence of swine influenza and other viral,
bacterial, and parasitic zoonoses in veterinarians. J Infect Dis
1997;176:1414- 5.
4. Nowotny N. The domestic cat: a possible transmitter of viruses
from rodents to man. Lancet 1994;343:921. 
5. Nowotny N. Serologische Untersuchungen von Hauskatzen auf
potentiell humanpathogene Virusinfektionen wildlebender
Nagetiere. Zentralblatt fr Hygiene und Umweltmedizin
1996;198:452-61.
6. Nowotny N, Fischer OW, Schilcher F, Schwendenwein I, Loupal
G, Schwarzmann Th, et al. Pockenvirusin-fektionen bei
Hauskatzen: klinische, pathohistolo-gische, virologische und
epizootiologische Untersuchungen. Wiener Tierrztliche
Monatsschrift 1994;81:362-9.
7. Juncker-Voss M, Prosl H, Lussy H, Enzenberg U, Auer H,
Nowotny N. Serological detection of Capillaria hepatica by indirect
immunofluorescence assay. J Clin Microbiol 2000;38:431-3.
8. Nowotny N, Uthman A, Haas OA, Borkhardt A, Lechner K,
Egberink HF, et al. Is it possible to catch leukaemia from a cat?
Lancet 1995;346:252-3.

Letters

Reply to Drs. Nowotny and Deutz

To the Editor: We thank Drs. Nowotny and Deutz for their Letter
to the Editor regarding our letter in the January-February issue of
Emerging Infectious Diseases. We agree that increased education
and research efforts regarding zoonoses would benefit not only at-
risk patients, but also veterinary and human health professionals.
We also applaud their efforts to provide serologic evidence of
exposure to zoonotic pathogens among veterinarians in Austria.
However, readers should be aware of the zoonotic potential of two
of the pathogens in their screening. Specifically, although both
animals and humans suffer from respiratory syncytial virus
infections, evidence is minimal for interspecies transmission of the
domestic animal and human strains. Similarly, bovine viral
diarrhea virus is an important bovine pathogen, but there is little
evidence for its ability to infect humans.

Christopher W. Olsen* and Leslie L. Barton
*University of Wisconsin-Madison, Madison, Wisconsin, USA;
and University of Arizona Health Sciences Center, Tucson,
Arizona, USA.

Emerging Infectious Diseases
National Center for Infectious Diseases
Centers for Disease Control and Prevention
Atlanta, GA

URL: http://www.cdc.gov/ncidod/EID/vol6no2/ascii/letters.txt

Please note that figures, equations, and tables are not available 
in ASCII format.  Many symbols do not convert to ASCII.