A hexavalent human rotavirus-bovine rotavirus (UK) reassortant vaccine designed for use in developing countries and delivered in a schedule with the potential to eliminate the risk of intussusception.

There is an urgent need for a rotavirus vaccine, because up to 592,000 infants and young children <5 years old die each year from rotavirus diarrhea, predominantly in the developing countries. We have developed a tetravalent human-bovine rotavirus (UK) reassortant vaccine with VP7 (G) specificity for serotypes 1, 2, 3, and 4, which has been shown to be safe, immunogenic, and effective in preventing severe rotavirus diarrhea. However, because of the emergence of VP7 (G) serotype 9 as an epidemiologically important serotype and the importance of VP7 (G) serotype 8 in focal areas, we are planning to add human-bovine (UK) reassortants with G8 and G9 specificity to the tetravalent vaccine, thereby formulating a "designed" hexavalent vaccine for universal use. In addition, we propose that the vaccine be administered orally in a 2-dose schedule, with the first dose given at 0-4 weeks of age and the second dose given at 4-8 weeks of age, when infants are relatively refractory to developing intussusception, thereby avoiding the age period when naturally occurring intussusception is most prevalent (i.e., ages 3-4 months through age 9 months). In this way, there may be the potential to eliminate or at least significantly decrease the risk of intussusception associated with rotavirus vaccination.

Severe acute respiratory syndrome: developing a research response.

When severe acute respiratory syndrome (SARS) first came to world attention in March 2003, it was immediately perceived to be a global threat with a pandemic potential. To help coordinate international research efforts, the National Institute of Allergy and Infectious Diseases convened a colloquium entitled SARS: Developing a Research Response on 30 May 2003. Breakout sessions intended to identify unmet research needs in 5 areas of SARS research--clinical research, epidemiology, diagnostics, therapeutics, and vaccines--are summarized here. Since this meeting, however, the identified research needs have been only partially met. Needs that have yet to be realized include reliable methods for early identification of individuals with SARS, a full description of SARS pathogenesis and immune response, and animal models that faithfully mimic SARS respiratory symptoms. It is also of the utmost importance that the global scientific community enhance mechanisms for international cooperation and planning for SARS research, as well as for other emerging infectious disease threats that are certain to arise in the future.