Persons planning to travel outside the US should be up to date on routine vaccines and, depending on their destination, duration of travel, and planned activities, may also receive certain travel-specific vaccines. Tickborne encephalitis and dengue vaccines, which are not available in the US, are reviewed in a separate article available online. Detailed advice for travel to specific destinations is available from the Centers for Disease Control and Prevention (CDC) at www.cdc.gov/travel/destinations/list. Recommendations for administration of vaccines as part of routine adult immunization are discussed in a separate issue.

The FDA has approved a subcutaneously administered 20% solution of human immune globulin (Cuvitru – Shire) for replacement therapy in patients ≥2 years old with a primary humoral immunodeficiency. Hizentra (CSL Behring), another subcutaneously administered 20% immune globulin solution, was approved in 2010 for the same indication. The IgG component of Cuvitru is similar to that of Gammagard Liquid and HyQvia, two subcutaneously administered 10% immune globulin formulations also manufactured by Shire and approved for treatment of primary immunodeficiencies.

Immune globulin (IgG) has been available for administration intravenously once every 3-4 weeks or subcutaneously once daily, once weekly, or every 2 weeks for treatment of primary immunodeficiencies. Now the FDA has approved human immune globulin 10% with recombinant human hyaluronidase (HyQvia – Baxter) for subcutaneous administration only every 3-4 weeks in adults with these disorders. The IgG component of HyQvia is identical to Gammagard Liquid, which was approved in 2005 for IV administration and in 2011 for SC administration.

Some patients with primary immune deficiency are injected with intravenous immune globulin (IVIG) every 3-4 weeks. Now a subcutaneous immune globulin (SCIG) has also been approved in the US for this indication (Vivaglobin - CSL Behring). SCIG has been used in Europe for about 10 years.

Intravenous immunoglobulin (IVIG) has 6 FDA approved indications and is prescribed off-label for many others. How many of these uses are justified is controversial.