Local school systems have canceled or delayed flu vaccine clinics this month because they have not received the needed supply of FluMist, the nasal spray vaccine given to children to stave off the nasty virus.
Clinics catering mostly to elementary school students in Howard, Baltimore, Harford and Anne Arundel counties and Baltimore City have been affected by the supply problem.
The FluMist is not expected to be delivered until December or later, school and health officials said.
A spokeswoman for MedImmune, the Gaithersburg-based manufacturer that makes FluMist, said the company "encountered some unforeseen challenges impacting production" of this year's supply of vaccine. She declined to specify what caused the delay.
Each year, pharmaceutical companies reformulate the vaccine based on the strains of the virus that are expected to be prevalent that season. Michele Meixell, a spokeswoman for AstraZeneca, MedImmune's parent company, said three strains are being replaced this season in a vaccine that protects against four strains.
"As a result, a significant portion of FluMist doses will be available later in the influenza season relative to prior seasons," Meixell said.
She said the company, which supplies FluMist across the country, has shipped about 5 million doses and expects to have more available later in the flu season. Delays have been reported elsewhere, including in Wisconsin, Missouri and Tennessee.
State health officials said they are not aware of shortages of flu vaccine shots in doctors' offices and health departments. CVS said it has shots available, for example.
Schools prefer the mist form of the vaccine because it is faster and easier to administer — and generally can be given without the tears that can come with shots.
There is no school requirement to get an influenza vaccine, though all Baltimore-area systems encourage vaccination and offer clinics.
"We prefer students go to their doctors, but we offer vaccinations in schools as a convenience," said Tiffany Tate, executive director of Maryland Partnership for Prevention, a nonprofit that partners with Howard and Baltimore counties to offer vaccinations to students.
She said typically in those two counties about one-third of the elementary students — or about 25,000 — are vaccinated in school each year, which helps take the burden off doctors' offices that can have thousands of patients on their rosters.
Tate said many parents have come to rely on the school service.
For that reason, Howard and Baltimore counties decided to delay and not cancel the majority of clinics. Baltimore County still plans to vaccinate some low-income students with small supplies of FluMist acquired early, according to the school system. The rest of the clinics in those counties could be held in December.
Despite the delay, "we still want everyone vaccinated," Tate said.
"If you don't go to your doctor and you still want to be vaccinated and you can wait until December, we'd love to have you," she said.
Harford and Anne Arundel school systems canceled in-school clinics but might reschedule if a supply becomes available.
In an email sent to parents Tuesday, Harford officials said that clinics scheduled for three days in October and November had been canceled. "At this time we do not have any FluMist or other seasonal flu clinics scheduled," officials said.
"This manufacturing delay is an unfortunate turn of events," said Dr. David C. Rose, acting health officer for Anne Arundel County. "The FluMist vaccination program [for schools] simply could not move forward without knowing when we would receive an ample supply of the nasal spray vaccine. We hope to resume the program next year."
Carroll County expects to formulate a plan shortly to ensure "children that are at greater risk" are vaccinated in a timely manner, Health Department officials said Wednesday.
The flu season usually lasts until March, though the peak tends to be in January or February. Flu activity now is sporadic in Maryland and most of the country.
The federal Centers for Disease Control and Prevention recommends that everyone 6 months or older be vaccinated against flu. The mist is available to those ages 2 to 49.
While early studies show that the mist is slightly more effective in young people, the CDC does not recommend one form of vaccination over the other.
And because it is a preventive measure, insurance plans cover the vaccine with no out-of-pocket costs to consumers.
The CDC maintains that an annual vaccine — which is reformulated each year to better protect against whatever virus strains are circulating — is necessary because its effectiveness wears off.
Flu usually sickens 5 percent to 20 percent of the U.S. population each year. More than 200,000 are typically hospitalized, and thousands die from complications. The young, elderly and pregnant, as well as those with underlying health conditions, are most at risk.
Many health departments still plan to continue with general clinics. While Anne Arundel canceled its school clinics, the county will hold a drive-through clinic offering the shot version from 11 a.m. to 6 p.m. Oct. 21 at Navy-Marine Corps Memorial Stadium in Annapolis. Officials said they also have some high-dose vaccine recommended for seniors.
Baltimore Sun reporters Liz Bowie and Jon Kelvey contributed to this article.