Seventy-seven male British soldiers and 1 woman, all stationed within the Eastern Sovereign Base Area (ESBA) garrison in Cyprus, contracted a Fever in the period December 1974-May 1975.

No obvious cases of the infection occurred in the large Cypriot refugee population, mostly shepherds, who had crowded into the ESBA area with their flocks after the Cyprus invasion in August 1974. However, investigation revealed 21 outbreaks of abortion in mixed flocks of sheep and goats in the southeastern coastal region; 11 of these flocks grazed in and around the ESBA.

Infection in the humans was acquired by inhalation of dust from brush contaminated with rickettsial parturition products. The brush areas were frequented by the soldiers in their basic military duties.

Of the patients with Q Fever, 46 (59%) developed pneumonia. Of 30 cases investigated, 24 (80%) had biochemical evidence of hepatitis, although none became clinically jaundiced. Three patients (4%) suffered pericarditis, and 10 (13%) had proteinuria without other evidence of nephropathy. Although a therapeutic trial was not conducted, treatment with tetracycline appeared to have little effect on the course of the disease.

Complement fixation tests for Coxiella burneti, using the phase 2 antigen, were performed. Of 50 asymptomatic soldiers who served in the garrison during the epidemic, 15 (30%) had antibody titers of 1:10. Of 30 soldiers who were stationed on the fringe of the ESBA close to the Turkish line, 7 (14%) were serologically positive. Of 154 soldiers in the Swedish United Nations contingent, operating outside the ESBS in the southeastern region also close to

Epidemiologic Notes and Reports

the Turkish line, 17 (11%) had antibody titers of >1:10. The prevalence of seropositivity in these 3 groups was directly proportional to the sheep population in their respective areas. Serologic testing of 100 Cypriots who were not directly connected with shepherding revealed that 59% had titers of 1:10.

The Central Veterinary Laboratory in Cyprus had observed, since 1970, that a small number of placentae from aborting sheep and goats contained numerous rickettsialike bodies associated with inflammation and necrosis of the cotyledons. These rickettsiae infected abortions usually occurred in the last month of pregnancy, with the dams showing no evidence of illness. From each of 10 flocks 10 serum samples were obtained from 10 aborting animals (approximately 3 months after abortion) and from 10 nonaborting animals. Complement fixation tests using phase 2 antigen showed that in the aborting group 70 of 97 (72%) were serologically positive for C. burneti; in the nonaborting group, 45 of 102 (44%) were positive. The titers in the aborting groups were also significantly higher. There was no serologic evidence that chlamydia or brucella caused the abortions.

Reported by Lt Col AJ Spicer, RAMC, Consultant Physician, British Military Hospital, Dhekelia, Cyprus; Mr RW Crowther, UNDP/ FAO, Microbiologist, Central Veterinary Laboratory, Athalassa, Cyprus; Col EE Vella, L/RAMC, Assistant Professor of Pathology, Royal Army Medical College, London; Capt R Miles, RAMC, Physician, British Military Hospital, Dhekelia, Cyprus; Mr G Pitzolis, District Veterinary Officer, Larnaca, Cyprus; Professor E Bengtsson, Karolinska Institutet, Infektionsklinikerna, Stockholm, Sweden; Dr K Polydourou, Chief, Veterinary Services, Ministry of Agriculture, Cyprus; and Viral Diseases Div, Bur of Epidemiology, CDC.

Approximately 3 hours after attending a church conference luncheon in South Pasadena on November 12, 1975, 126 of the 158 persons attending became ill. Symptoms included nausea (94%), vomiting (97%), diarrhea (98%), and abdominal cramps (51%).

Fifty-four patients were seen by a doctor and 23 were hospitalized, some for several days. Those requiring lengthly hospitalization had complications from other medical problems. Although the age range of those at the conference was 27 through 85, most were in their 60s and 70s.

The luncheon menu consisted of chicken salad, rolls, pumpkin pie, apple pie, pickles, crackers, tea, coffee, and a cream substitute (Table 1). Food-specific attack rates implicated the chicken salad (Fisher's 2-tail test, p<.002). Greater than 400,000 coagulase-positive staphylococci were isolated from samples of the chicken salad,

Investigation disclosed that the 60 pounds of chicken used to prepare the salad were boiled the evening of November 10 and then placed in small apartment-sized refrigerators overnight. The next day the chicken was cut up, celery, peas, and pineapples were added, and, after remaining at room temperature an undetermined amount of time, the salad was refrigerated overnight.

The following morning, November 12, the salad was removed from refrigeration long enough to add mayonnaise

served at

11:15 am. The food was eaten in the period from 12:151:00 pm.

Nasal cultures from 8 food handlers, 7 of whom had become ill, grew coagulase-positive staphylococcus. Phage typing of 7 of these cultures revealed that 3 were of the same phage type (53/77/84) as the staphylococci isolated from the chicken.

Reported by A Cobb, RS, MSEH, F Desch, PHN, R French, RS, WB Tommaney, MD, Pinellas County Health Dept., St. Petersburg; C Hartwig, PhD, State Regional Laboratory, Tampa; CL Nayfield, MD, State Epidemiologist, Florida State Div of Health; and Enteric Diseases Br Bacterial Diseases Div, Bur of Epidemiology,

Sixteen members of an extended family in Yakima, Washington, were exposed to organic mercury in the first 3 months of 1976. Their mercury source was treated seed grain, used as chicken feed, and exposure resulted from egg consumption. Early recognition of the hazard prevented development of clinical illness.

A young male member of the family had obtained the mercury-treated grain in January 1976 while he was scavenging at a city dump. He removed approximately 1 ton of mixed grain, chaff, and dirt from the dump from January 3-15. (Since then, another 5 to 10 tons of the mixture, which may have represented granary sweepings, have disappeared from the dump.) The family began to feed the scavenged grain to their 45 chickens soon after it was obtained. No illness was noted in the flock.

On February 19 in an unrelated incident, 400 pounds of mercury-treated barley were reported missing by a Yakima County farmer. Local news media circulated widely a description of the pink color of the treated grain and reviewed the human health hazards associated with its improper use. As a result of this publicity, a concerned local citizen notified the Yakima County sheriff's office on March 1 that she had received 3 sacks of mixed grain containing pink kernels. The grain had been given to her by the above described family. The sheriff's office and the Washington State Department of Agriculture investigated promptly and on March 2 impounded the scavenged grain. The members of the family were medically examined March 3-5. Three members reported nonspecific symptoms, but none of these appeared related to mercury exposure.

Analysis of 8 grain samples by atomic absorption spectrophotometry showed an average total mercury content of 15,000 parts per billion (ppb) (1). By gas chromatography, methyl and phenyl mercury was found in the grain in ratios of 1:2 and 1:5. Analysis of an egg from a chicken that had eaten the treated grain showed organic/inorganic mercury levels of 596/1,902 ppb in the yolk and of 2,719/

98 ppb in albumin. Whole blood samples from family members showed total mercury levels ranging from 0.9 to 20.2 ppb; the highest level was found in the man who ate 8 eggs per day. All of the blood mercury levels were below the range at which symptoms reportedly occur.* There was a close correlation noted between blood mercury levels and average daily egg consumption (r=0.92).

Reported by RG Atwood, MD, P Gates, PHN, M Patnode, PHN, Yakima County Health District; R LacQuaye, Yakima County Sheriff's Dept; T Clarkson, PhD, M Greenwood, MS, JC Smith, PhD, University of Rochester; E Nedrow, Washington State Dept of Agriculture; JA Beare, S Milham, Jr, MD, TL Nghiem, MD, DrPH, State Epidemiologist, Washington State Dept of Social and Health Services; Field Services Div, and Environmental Hazards Activity, Cancer and Birth Defects Div, Bur of Epidemiology, CDC. Editorial Note: Publicity and prompt action prevented in this instance the development of the acute, often irreversible neurologic illness that has been seen in previous episodes of organic mercury poisoning (3, 4).

The typical symptoms in mild cases include paresthesias, fatigue, and inability to concentrate. More severe cases progress to concentric narrowing of the visual fields, hearing difficulties, emotional lability, ataxia, paralysis, coma, and death.

References

1. Giovanoli-Jakubczak T, Greenwood MR, Smith JC, et al: Determination of total and inorganic mercury in hair by flameless atomic absorption and of methyl mercury by gas chromatography. Clin Chem 20(2):222, 1974

2. Berglund F, Berlin M, Birke G et al: Methyl mercury in fish, a toxicologic-epidemiologic evaluation of risks, report from an expert group. Nord Hyg T, Supplement 4, 1971

3. Kurland LT, Faro SN, Seidler H: Minamata disease: The outbreak of a neurologic disorder in Minamata, Japan, and its relationship to the ingestion of seafood contaminated by mercuric compounds. World Neurol 1:370-395, 1960

4. Pierce PE, Thompson JF, Likosky WH et al: Alkyl mercury poisoning in humans: Report of an outbreak. JAMA 220:14391442, 1972

*A Swedish expert committee has recommended that whole blood mercury levels above 20 ppb be considered to pose a mercury poisoning hazard (2).