Flu shots for infants and toddlers might be hard to find in the opening weeks of this year's influenza season because of manufacturing problems that have left some Minnesota clinics in short supply.

Doctors at Children's Hospitals and Clinics of Minnesota have been delaying flu shots for ages 3 and under due to delayed shipments of pediatric vaccine from one manufacturer, Sanofi Pasteur, said Children's spokeswoman Katie Heinze.

Children's expects to have plenty of vaccine before flu cases start to spike — usually after Thanksgiving — but meanwhile, Heinze said, parents can take the preventive step of getting their own shots so they don't become carriers who pass the virus to unprotected children.

"Get your vaccine to protect your infants," she said.

Other health providers are reporting better supplies. MVNA, formerly known as the Minnesota Visiting Nurse Agency, a major provider of public flu clinics, reported a full supply of vaccine for its events. Those include a new Flu Fighter To-Go program which sends a nurse out to any group of 20 people who want to get flu shots together.

Sanofi is the only manufacturer of injectable vaccine for U.S. children 3 and younger. GlaxoSmithKline is also behind schedule in influenza vaccine production. Despite the production delays, spokesmen for both companies said they expect the bulk of their U.S. vaccine doses to be shipped by month's end.

A nasal flu mist is in adequate supply as an alternative to children's injectable vaccine, but it is recommended only for healthy children ages 2 and older because it contains a live, but weakened form of influenza virus. Vaccination is recommended by federal health authorities for children starting at 6 months of age.

Children's ran into supply problems because it ordered all quadrivalent vaccine, a newer form which protects against two A strains of influenza and two B strains.

Allina Health is similarly waiting for its quadrivalent doses, but has supplies on hand of trivalent vaccine, an older but cheaper form that protects against two A strains and only one B strain. "Parents should not hesitate to get their kids immunized with the trivalent vaccine," said Allina spokesman Tim Burke, "because that is so superior to having no immunization at all."

The shortage at Children's includes doses for older children and adults. The health system has prioritized its supply for patients, resulting in delays in vaccination events for its employees.

Jeremy Olson • 612-673-7744