The US FDA has approved Merck’s combination vaccine Proquad [Measles, Mumps, Rubella and Varicella (Oka/Merck) Virus Vaccine Live] for simultaneous vaccination against measles, mumps, rubella (German measles) and varicella (chickenpox) in children 12 months to 12 years of age.

Proquad is the first and only vaccine approved in the United States to help protect against these four diseases in a single shot. Proquad is also approved for use in children 12 months to 12 years of age if a second dose of measles, mumps, and rubella vaccine is to be administered.

According to a company release, Proquad combines two well-established Merck vaccines - M-M-R II (Measles, Mumps and Rubella Virus Vaccine Live) and Varivax [Varicella Virus Vaccine Live (Oka/Merck)]. Vaccination with M-M-R II has contributed to a greater than 99 per cent reduction in the United States in the incidence of measles, mumps and rubella.

“The approval of Proquad makes it more likely that more children can gain protection against these four diseases because fewer shots can potentially mean better compliance," Henry Shinefield, clinical professor of paediatrics and dermatology, University of California School of Medicine at San Francisco, said adding, "By allowing vaccination against chickenpox to occur simultaneously with vaccination against measles, mumps and rubella, Proquad can help increase the number of children vaccinated against chickenpox at the earliest recommended time -- upon a baby's first birthday."