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The dual potential of poxviruses to be cytolytic and tumorgenic has been extended. Yaba monkey tumor virus formed foci on monkey and human embryonic cells. Cytolytic or plaque-forming virus was isolated from Yaba tumor homogenates by selective sucrose centrifugation and passage through monkey or human embryonic cells. Monkey pox virus (MPV) was cytolytic for monkey cells or human embryonic cells, but upon passage onto young monolayers of human carcinoma cells, HeLa, produced a restricted cytopathic effect on first transfer, foci on second transfer and cytolysis after the fourth transfer. If HeLa monolayers were compact, the rapid growth precluded overt expression of cytolytic MPV. Electron micrographs of cytolytic Yaba indicated that Yaba development was similar to vaccinia and MPV but not totally organized. Growth curves of vaccinia, MPV and cytolytic Yaba were essentially identical in monkey and human embryonic cell lines.

During 1979, an outbreak of mixed enterovirus infections occurred in Kansas City and adjacent communities. Sixty-six enteroviruses and 7 adenoviruses were recovered from 73 persons in a survey hospital population. Twenty-eight persons yielded echovirus type 11, 22, echovirus type 6, and 16 either echovirus type 9 or Coxsackieviruses group B, types 2 and 3. This study describes some of the clinical, virologic and epidemiologic characteristics of the outbreak. A major finding relates to the recovery of enteroviruses from cerebrospinal fluids with essentially normal leukocyte counts.

New information accrues periodically in the ledger accounting for infections and diseases associated with the human enteroviruses. The discoveries of "new" serotypes and how they affect people are subjects of continuing attention. Some other relevant information on "old" serotypes relates to variations in age-specific attack rates and associated morbidity and mortality for neonates and older infants. Among the morbidity reports are recounts during outbreaks of virus-positive cerebrospinal fluids (CSFs) that initially may not have cytological or biochemical abnormalities. Prolonged enterovirus infections may develop in persons having agammaglobulinemia. Lastly, some provocative associations concern the pathologic expressions of enteroviruses in the development and persistence of injury to the heart (myocardiopathies) and the pancreas (insulin-dependent diabetes mellitus).

The MLM herpesvirus is infectious for cynomolgus monkeys. The disease in this species, possibly modulated by preinoculation antibody resembles human varicella. Virus has been recovered from blood during the early incubation period, and from liver, lymph nodes, kidney, bladder and urine during the eruptive period of infection. The major target organs were skin and liver; specific pathological changes developed in both. Appropriate antibody responses, including those to Herpesvirus varicellae followed infections mounted by parenteral inoculation of cynomolgus monkeys.

The Medical Lake macaque (MLM) virus produced varicelliform eruptions in cynomolgus monkeys. Not all experimentally infected monkeys developed overt disease; viremia was found, and specific antibodies were detected. Specific lesions were found in skin, lymph nodes, and spleen. Focal inflammatory lesions were present in liver, pancreas, and lung (after intratracheal instillation of virus). MLM virus was recovered from these and other organs. The temporal movements of MLM virus in and out of primary and secondary target organs remained partially unsolved. MLM virus is related to the Wu strain of varicella virus.