[Use of the hemadsorption method to demonstrate the African swine fever virus in Angola].

Attempts were made to modify the hemadsorption method used in the demonstration of the African swine fever virus. Use was made of fourteen strains of the virus with known hemadsorption properties and infectious titers, which were replicated in leukocyte cultures of swine blood, in three variants: (a) at direct infection of the cultures without changing the medium; (b) at infecting with changing the medium and adding erythrocytes to the new medium; and (c) infecting the cultures with changing the medium and adding 0.2 cm3 2 per cent erythrocyte suspension to each test tube at the 16th hour following infection. It was shown that in its third variant the hemadsorption method yielded most clearly expressed results, and all suspective fields were eliminated, the result being recorded as early as the second hour after the addition of erythrocytes, i.e., at the 18th hour following the infecting of cultures. With the third modification of the method no phagocytosis of the present erythrocytes effected by the emerging macrophages, which is common for the other two variants, could take place.