The nation’s drug companies are planning to supply enough flu vaccines for half the country’s population, but it is coming later than planned, in October instead of August, according to the Centers for Disease Control and Prevention.

In a notice, CDC said, “Some companies have communicated information to their customers about delays in shipments that had originally been anticipated for August and September. Despite these early season shipping delays, however, manufacturers anticipate the majority of their flu vaccine distribution will occur by the end of October.”