The FDA has approved a new Japanese encephalitis vaccine (Ixiaro - Intercell/Novartis). It will replace JEVax (Sanofi Pasteur), which has had tolerability and safety problems and is no longer being manufactured.

Concerns have arisen anew about possible use of biological weapons. The pathogens considered most likely to be used for this purpose are discussed in this article. A good source for additional information is www.usamriid.army.mil/education/bluebook.html.

Some readers have asked why the Medical Letter article on Lyme Disease Vaccine (Vol 41, p. 29) concluded that its long-term safety is worrisome....

The FDA has licensed Adacel (Aventis Pasteur) and Boostrix (GlaxoSmithKline), two new combination vaccines that include tetanus toxoid, diphtheria toxoid and acellular pertussis antigens (Tdap), for use as a booster in adolescents and adults. In the past, older children and adults were not re-immunized against pertussis because of concerns about reactions to the whole-cell vaccine previously used in younger children. The CDC Advisory Committee on Immunization Practices (ACIP) and the American Academy of Pediatrics (AAP) have recommended that either of the new Tdap vaccines replace routine...

On December 18, 2020, the FDA issued an Emergency Use Authorization (EUA) for the Moderna mRNA-based vaccine for prevention of COVID-19 in persons ≥18 years old. The Pfizer-BioNTech mRNA-based vaccine received an FDA EUA for the same indication in persons ≥16 years old on December 11, 2020.

The FDA has licensed Capvaxive (PCV21; Merck), a 21-valent pneumococcal conjugate vaccine, for prevention of invasive pneumococcal disease (IPD) and pneumococcal pneumonia in adults. Four other pneumococcal vaccines are currently available in the US: Prevnar 20 (PCV20), Vaxneuvance (PCV15), and Prevnar 13 (PCV13) are conjugate vaccines licensed for use in persons ≥6 weeks old, and Pneumovax 23 (PPSV23) is a pneumococcal polysaccharide vaccine licensed for use in persons ≥2 years old (see Table 1).

The FDA has approved Bexsero (Novartis/GSK), a vaccine that protects against invasive meningococcal disease caused by Neisseria meningitidis serogroup B. It is the second serogroup B meningococcal vaccine to be approved in the US; Trumenba was the first. Both vaccines are approved for use in persons 10-25 years old. Bexsero is approved in Europe, Canada, and Australia for use in children as young as 2 months old.

The FDA has approved an adjuvanted, recombinant varicella zoster virus (VZV) vaccine (Shingrix – GSK) for prevention of herpes zoster (shingles) in adults ≥50 years old. Shingrix is the second herpes zoster vaccine to be approved in the US; Zostavax, a live-attenuated VZV vaccine approved for the same indication, has been available since 2006.

A new Haemophilus influenzae type b capsular polysaccharide vaccine conjugated with diphtheria toxoid (ProHIBiT - Connaught) was recently marketed in the USA. It is being promoted as a replacement for older, unconjugated H. influenzae vaccines (b- Capsa I; Hibimune; HibVAX) previously reviewed in The Medical Letter (Volume 27, page 61, 1985).

The FDA has recently approved RotaTeq (Merck), an oral live, human-bovine reassortant rotavirus vaccine, for use in infants to prevent rotavirus gastroenteritis, a frequent cause of severe diarrhea in infancy.