Monkeypox - Continued

the residual evidence of pox virus infection. Surveys in the different areas provided similar results. Vaccination scars were present in 80% or more of those persons 5 years and older but were present in less than half of those under 5 years of age. A large susceptible population was thus present in each of the areas, since 13 of the 21 known monkeypox cases had occurred among children 5 years of age and younger [and only 2 cases, ages 24 and 30, had ever been vaccinated; in these 2 individuals, however, vaccination protection had elapsed. It appears that immunization against smallpox is cross-protection for monkeypox.] No pockmarks datable to the period since 1971 were detected. Similar studies will be conducted in Zaire in the near future.

Although naturally occurring outbreaks of monkeypox in primates have never been documented, outbreaks of monkeypox infection in captive monkey colonies have occurred on 10 occasions since description of the first outbreak in 1958. The last known outbreak of monkeypox among captive monkeys occurred in 1968. There is no

ready explanation for the apparent cessation of such outbreaks.

During February 1976, 24 epidemiologists and virologists from 10 countries met in Geneva to discuss in depth the present status of knowledge of monkeypox virus and other smallpox-related viruses, and to advise on future studies. The group endorsed the conclusions of a previous group convened in 1972-specifically, that available evidence so far indicates that there is no animal reservoir for smallpox. Further, none of the smallpox-related viruses has demonstrated a capability to infect and to sustain transmission in man. However, because so little is known about these viruses, the group strongly recommended that surveillance for human cases of smallpox-like illness be continued and strengthened, especially in tropical rain forest areas in Africa, where all previous cases of monkeypox have occurred.

Reported by the World Health Organization in the Weekly Epidemiological Record 51(19):149-150, May 7, 1976.

The State Department of Human Resources first learned of the outbreak in early December when it was informed that 2 children with culture-proven pulmonary blastomycosis were hospitalized at a university hospital in the state. Both of the children lived in or near Enfield, a town of 3,200 in the northeast region of the state.

When a telephone survey of all area hospitals was conducted, another child was found to be hospitalized with pulmonary blastomycosis. In December 1975 and January 1976, 2 more patients, both adult females, were hospitalized in a town near Enfield with a similar diagnosis. All three patients were from the Enfield area. Despite intensive surveillance, no more cases have been reported. Interviews with the patients and/or their parents, as well as on-site inspection, revealed that all but one patient lived a peanut farm; otherwise, there was no known common exposure nor were the patients acquainted. Dates of onset in all cases, however, were in November, a period approximately 6 weeks after peanuts-the main agricultural product in the community-were harvested.

near

On January 8, 36 of the patients' close contacts had blood samples drawn for complement fixation (CF) titers. All were negative for antibodies to blastomycin and histoplasmin. The contacts also had chest X-rays, which were negative. All contacts also were skin-tested with both histo

plasmin and blastomycin; all were negative, except one, who was positive for both.

Soil and vegetation samples, obtained from each patient's dwelling and from neighboring peanut farms, were negative for Blastomyces dermatitidis. Two dogs (both belonging to relatives of 1 patient) were bled; both had CF titers of 1:8 to blastomycin. Another dog, which belonged to a patient, was found to be ill. It was bled and had a titer of 1:16. When it was sacrificed and autopsied, cultures of organs for B. dermatitidis were negative.

All patients have been discharged and are doing well. Reported by M Furcolow, MD, C Smith, DrPH, University of Kentucky Medical Center; H Gallis, MD, Duke University Medical Center; D Mayock, MD, University of North Carolina; T Mitchell, PhD, Duke University Medical School; JA Phillips, PhD, North Carolina State University at Raleigh; L Hoag, MD, Halifax County (NC) Health Dept; F Bradham, J Freeman, DVM, MP Hines, DVM, State Epidemiologist, JN MacCormack, MD, North Carolina Dept of Human Resources; and Field Services Div, Bur of Epidemiology, CDC.

Editorial Note: Blastomycosis is a mycotic disease found most often in the central and southeastern United States and, less often, in Canada and Africa. It most commonly infects the lungs. It can be fatal if not treated, although there have been untreated individuals who recovered (2,3).

The mode of transmission is not known but it is probably from soil to man by inhalation of air-borne spores. The spores have been isolated from the soil in Lexington, Kentucky, and in the Augusta, Georgia, area (4,5). Laboratory workers also have been infected by isolates of Blastomyces dermatitidis (6). Dogs frequently contract this disease but canine infections are not known to be transmitted to man.

The temporal association between the peanut harvest and onset of this outbreak suggests a common source of exposure; however, the significance of this exposure is not clear, since soil cultures were negative and one patient gave no history of this kind of exposure.

References

1. Smith JG, Harris JS, Conant NF, Smith DT: An epidemic of North American blastomycosis. JAMA 158:641-646, 1955

2. Tosh FE, Hammerman KJ, Weeks RJ, Sarosi GA: A commonsource epidemic of North American blastomycosis. Am Rev Respir Dis 109:525-529, 1974

Blastomycosis - Continued

3. Baum GL, Lerner Pl: Primary pulmonary blastomycosis: A laboratory-acquired infection. Ann Intern Med 73:263-265, 1970 4. Denton JF, McDonough ES, Ajello L, Ausherman RJ: Isolation of Blastomyces dermatitidis from the soil. Science 133:1126

1127, 1961

5. Denton JF, DiSalvo AF: Isolation of B. dermatitidis from natural sites at Augusta, Georgia. Am J Trop Med Hyg 13:716-722, 1964 6. Landay ME, Schwartz J: Primary cutaneous blastomycosis. Arch Dermatol 104:408-411, 1971

The first case of louse-borne relapsing fever documented in the United States in this century was diagnosed in Dayton, Ohio, in April 1976. Borrelia recurrentis was demonstrated in the patient's blood as well as in lice removed from her hair. The patient, an 18-year-old woman, had been ill since shortly after immigrating to this country from Ethiopia 3 weeks previously.

On April 13, the patient was admitted to a Dayton hospital for treatment of previously diagnosed malaria. Admission physical examination was normal except that her liver was palpable 2 cm below the costal margin and was slightly tender, and her thyroid was diffusely enlarged. Chest and abdominal radiographs, electrocardiogram, thyroid function tests, and multiphasic biochemical screening of serum were normal. Urinalysis was normal except for a trace of albumin. VDRL and febrile agglutinin tests including proteus OX 19, OX K, and OX 2 were negative. Mantoux testing resulted in a 20 mm reaction. Blood and urine cultures were negative.

Hematologic examination revealed a total red blood cell count of 3.37 million/mm3, hemoglobin of 9.3 grams/ 100 ml, mean corpuscular volume of 83 cubic microns, and an hematocrit of 28.4%. Her total WBC count was 4,300/ mm3, and the platelet count was 93,000/mm3. Glucose 6 phosphate dehydrogenase was 1.4-2.0 IU/g of hemoglobin. (Normal is 3.1 to 7.6.)

Examination of a Wright's stained blood film revealed many Plasmodium vivax. Loosely coiled, thread-like organisms which were <1 micron in width and 10 to 12 microns in length and resembled B. recurrentis were also observed. These organisms were found to be motile when examined with darkfield microscopy. The presence of both organisms in a blood film was confirmed at CDC.

The patient was started on chloroquine therapy for her malaria shortly after admission. Her temperature rose to 39.4°C that evening and dropped to 37.2°C by the morning following admission. She remained afebrile the remainder of her clinical course. (Continued on page 211)