Sero-Prevalence of Antibodies against Varicella Zoster Virus in Children under Seven-Years Old in 2012 in Tehran, Iran - Vojgani, Yasaman; Zarei, Saeed; Rajaei, Samira; Chamani-Tabriz, Leili; Ghaemimanesh, Fatemeh; Mohammadinia, Nematallah; Jeddi-Tehrani, Mahmood (Iranian Journal of Public Health)