Chickenpox is an illness caused by the varicella zoster virus (VZV), which is a member of the herpesvirus family.The illness lasts between 5 and 10 days causing an itchy, blister-like rash, fever, headache, fatigue, and loss of appetite.hickenpox is an illness caused by the varicella zoster virus (VZV), which is a member of the herpesvirus family.
Mexicoâs ten largest cities (2009 population) are: Mexico City 19,982,000 (Metropolitan Area) Guadalajara 4,365,000. Monterrey 3,986,000. Puebla 2,647,000.
1 The population density in Mexico is 66 per Km2 (171 people per mi2). 2  The total land area is 1,943,082 Km2 (750,228 sq. miles) 3  78.1 % of the population is urban (100,696,829 people in 2016)  The median age in Mexico is 27.8 years.