Annual immunization against influenza A and B is the most effective method of preventing infection and has been shown to reduce associated complications.

Quantiferon - TB Gold (Cellestis) is a T-cell interferon-gamma release assay approved by the FDA as an alternative to the tuberculin skin test for diagnosis of infection with Mycobacterium tuberculosis (TB). An earlier assay (Quantiferon-TB), which is no longer commercially available, was approved by the FDA in 2001. Other interferon-gamma release assays (IGRAs) are available abroad.

An article (Med Lett Drugs Ther 2007; 49:41) on sunscreens in the May 21 issue of The Medical Letter included a statement that if sunscreens and the insect repellent DEET are used together, DEET should be applied first to avoid decreasing the effectiveness of the sunscreen. However, a recent in vitro study in human skin found that sunscreen increases absorption of DEET, especially when DEET is applied first (T Wang and X Gu. J Pharm Pharm Sci 2007; 10:17). Whether this practice could cause clinical toxicity is unclear. Some travel experts recommend applying sunscreen first.

The Medical Letter article (Med Lett Drugs Ther 2007; 49:71) on Low-Dose Transdermal Estrogens said that Elestrin has been marketed in Europe since 1976. Actually it is EstroGel (Ascend Therapeutics), a similar product, that has been available in Europe since 1976.