[1] GR Micro Ltd, London NW1 3ER, England
[2] Univ Witwatersrand, Parktown, South Africa
[3] Sera & Vaccines Cent Res Lab, Warsaw, Poland
[4] Rollins Sch Publ Hlth, Atlanta, GA USA
[5] Nagasaki Univ, Sch Med, Nagasaki 852, Japan
[6] Mt Sinai Hosp, Toronto, ON M5G 1X5, Canada
[7] Fleury Med Diagnost Ctr, Sao Paulo, Brazil
[8] Univ Leipzig, Leipzig, Germany