Titration of Trachoma Virus with Observations on Yolk-sac Infection and Sensitivity to Oxytetracycline, using the Single-dilution method

SUMMARY: The T'ang strain of trachoma virus was titrated in chick embryo yolk sac by a single-dilution method (Golub, 1948), using 3-6 eggs/dilution. The limitations incurred by the use of small numbers of eggs are discussed. The method was used to make observations on the fate of virus after inoculation into the yolk sac, and to study the sensitivity of virus to oxytetracycline. The method was found to be unsuitable for titration of neutralizing antibodies in fowl serum.