Human plague episode in the District of Khawlan, Yemen.

Abstract We penetrated the disputed, embattled, and isolated territory of Khawlan in the northern highlands of Yemen during June 1969 to investigate an epidemic of fatal disease that had already killed 15 persons in two villages in the valley of Wadi el Jaber. Although our time and facilities were strictly limited, we collected detailed information of the history of this epidemic, identifying it as plague. Diagnostic specimens collected from a patient in whom plague infection was developing, and from a body exhumed 24 hours after death, resulted in two isolations of Yersinia pestis. The patient's condition, and the description of the illness in the dead persons by their relatives, led to the conclusion that the episode was an epidemic of authocthonous pulmonary plague. Rattus rattus was in the houses and Meriones rex, Mus musculus, and Gerbillus group famulus or garamantis were in the fields of the infected villages. Also Gerbillus gerbillus or Gerbillus arduus was captured in the sand desert near Saleeb between Sa’dah and Najran. No fleas were collected from rodents or in houses. The cultural characteristics of the Y. pestis isolates support the view of R. Pollitzer that the Asir plague focus is a part of a vast enzootic plague area in Western Asia.