Kenneth W. Bernard

Q Fever Control Measures: Recommendations for Research Facilities Using Sheep

Q fever (Query Fever) is a zoonosis caused by the rickettsia Coxiella burnetii. domestic ungulates such as sheep, cattle, and goats serve as the reservoir of infection for humans and shed the desiccation-resistant organism in urine, feces, milk, and especially in birth products. In humans the illness is generally mild; however, Q fever hepatitis is often seen and Q fever endocarditis is an uncommon, but frequently fatal complication. Q fever long has been recognized as an occupational hazard among persons working with animals or animal products, and in laboratories working with C. burnetii. Recently, Q fever outbreaks have occurred in medical research facilities using sheep as research animals. Recommendations are presented for reducing the risk of exposure to Q fever in persons not working with sheep in research facilities that use sheep. In addition, recommendations are presented for reducing the risk of infection in persons who work with sheep in research facilities.

Failure to achieve predicted antibody responses with intradermal and intramuscular human diploid cell rabies vaccine.

In a study to compare the immunogenicity of human diploid cell rabies vaccine (HDCV) given by intramuscular or automatic intradermal jet injection, neither method of administration resulted in antibody levels predicted by previous studies. 49 days after starting a series of three 0.1 ml doses of HDCV given intradermally, 85 volunteers had a geometric mean titre (GMT) of neutralising antibody to rabies of 1:170. 9 concurrent control subjects who received 1.0 ml doses of vaccine intramuscularly had a GMT of only 1:269. Although standard potency testing did not demonstrate that the vaccine used was subpotent , these results strongly suggest that the immunogenicity of HDCV is substantially less than previously reported.

An Outbreak of Acute Hemorrhagic Conjunctivitis in Central Minnesota

The only confirmed outbreak of acute hemorrhagic conjunctivitis in the continental United States during 1982 occurred in Brainerd, Minnesota. The disease first appeared in a 27-year-old woman during a trip to Tahiti. The patients two daughters (8 months old and 3 years old) developed mild conjunctivitis two days later. Although the symptoms of all three had completely resolved before they arrived in Brainerd, illness compatible with acute hemorrhagic conjunctivitis developed in five other individuals who shared a house with them there. Symptoms appeared within two days in four of the five and within three days in the fifth. All five had high neutralizing antibody titers to enterovirus 70 (1:128, 1:32, 1:32, 1:128, and 1:256) and one had high antibody titers to coxsackievirus A24 which may cause similar symptoms (less than 1:4 in all cases). The symptoms resolved without sequelae in all five patients within five days. These cases demonstrated that a person who is no longer symptomatic can still infect others and that an infected person can transmit enterovirus 70 for at least eight days after the onset of symptoms.

Q Fever and Experimental Sheep

In August 1983 a Symposium was held in Vancouver to discuss Q fever as a hazard to humans in contact with infected sheep. On the basis of new preliminary information presented and discussion at the Symposium, an attempt has been made in this document to supplement published guidelines for the conduct of sheep research.