Thankfully, it’s safe to put away the Kleenex and the Nyquil. The flu season is winding to a close – and it goes down as the worst in recent years, according to the Centers for Disease Control and Prevention.

The flu vaccine was partly to blame, according to the CDC. Flu vaccines, which are usually 70% to 90% effective, contain three strains of the flu that researchers pick as the most likely to make people sick. This season, two of the three strains that infected the general population were not found in the vaccine, rendering it only 44% effective, the CDC said late last week.

A total 9% of all adult deaths in early March were a result of the virus, whose presence remained above an epidemic threshold for more than 13 weeks, according to the agency. The last such flu season was 2003-2004, which didn’t last quite as long but resulted in more overall deaths.

Recent discoveries that track the global spread of the flu will hopefully allow doctors and scientists to more accurately predict which contagions to put in their vaccines. Those findings were published Friday in the journal Science.