A crisis developed this week when the British government suspended the operations of one of the two companies that makes flu vaccines for the United States.

While it’s unclear why the vaccine maker was shut down and vaccines deemed unsafe, what is clear is the pinch the United States faces.

The company, Chiron Corp., produces between 46 million and 48 million doses of the flu vaccine given in this country, almost half the total supply. Because it takes several months to manufacture the vaccines, there’s little opportunity to find that many doses from another source.

Millions of people at high risk from the flu will not be able to receive vaccinations. According to the Centers for Disease Control, the people who need the vaccines the most are children between the ages of 6 months and 23 months, senior citizens 65-years-old and older, pregnant women and people with chronic medical conditions.

End result: The government may be forced to ration vaccines for those most in need.

Rationing is a dirty word in American medicine and we can expect a run on available vaccines. People who aren’t in the high risk categories should carefully consider getting a flu shot, knowing that the flu is most likely just an inconvenient discomfort for them but could be fatal for someone else.

The crisis points to the fragility of the world’s vaccine supplies. Just two companies make the 100 million annual doses distributed by the United States. When the problem developed with Chiron, the United States was left with nowhere to turn.

It’s time that the vaccine infrastructure was repaired. The government should commit to purchasing vaccines from several makers and, if necessary, subsidize their work. It would also be prudent to build excess capacity into the system so a single producer could not hold so much of the supply in its hands.

This year’s flu season may be more difficult without enough vaccines, but hopefully it will spur actions that will keep the problem from repeating.