In late September, Moscow municipal official Sergei Martyanov sent a series of text messages to his subordinates: “Colleagues!!!... What is this sabotage???”

Martyanov was expressing dismay at his staff’s apparent reluctance to volunteer for the human trials of Russia’s Sputnik V coronavirus vaccine, named after the Soviet-era satellite that triggered the space race, according to Reuters. The official in the Moscow department of city property said many quota spots for his staff to join the trial remained unfilled.

He said he had heard some workers were signing up to receive flu vaccines, making them ineligible for the coronavirus trial.

“Who are you trying to trick???” Martyanov said in the texts. “The coronavirus vaccine is the absolute priority!!!”

Anyone who had received the flu jab, he said, must still sign up for the Covid trial, allowing a month’s delay. He urged his colleagues to recruit friends and family into the trials. “At least two people per employee!”