Reliability of Information on Varicella History in Preschool Children

Abstract

ER. Reliability of information on varicella history in preschool children. Clinics. 2007;62(3):309-14. OBJECTIVE:To verify how reliable is the information provided by parents about the history of varicella in their children. METHODS: 204 parents of previously healthy children attending two municipal day-care centers of São Paulo city were interviewed between August 2003 and September 2005. A standardized form was filled out with information regarding age, sex, history of varicella and other diseases, drug use and antecedent of immunization, After medical history, physical examination and checking of immunization records, 5 ml of blood were collected for ELISA (in house) varicella test. Exclusion criteria were: age less than 1 year or more than 60 months, previous immunization against chickenpox, presence of co-morbidities or recent use of immunosuppressive drugs. Data were filed in a data bank using the Excel 2003 Microsoft Office Program and stored in a PC computer. The exact Fisher test was employed to calculate sensibility, specificity, positive and negative predictive values of history of varicella informed by children's parents. RESULTS: The age of the children varied from 12 to 54 months (median, 26 months; 49 (24%) children had positive history of varicella, 155 (76%) a negative or doubtful history. The predictive positive and negative values of the information were 90% and 93%, respectively (p = 0.0001). CONCLUSIONS:The degree of reliability of information about history of varicella informed by parents of children attending day care centers was high and useful to establish recommendations on varicella blocking immunization in day-care centers.

Immunological Responses to Varicella-Zoster Virus (VZV) in Basrah with Special Emphasis on the Pattern of Exposure

“…[15] Varicella is a highly contagious disease, particularly after the close contact as household contact or in collection environments such as day care centers. [16] In our locality, the life pattern of large families sharing same house, play a role in increasing the incidence of VZV infection among the urban areas. This results is consistent with a study done in Turkey which reported that varicella seropositivity was higher in large families with five or more members (91.2%) than small families with four or fewer members (80%).…”

Micro and macro population effects in disease transmission: the case of varicella

“…Classification bias is unlikely, as true subclinical varicella is rare and clinical diagnosis easy in children presenting lesions [20]. Recall bias should also be limited, given the large positive predictive and negative predictive values of varicella history for school-aged children (95 % and 90 %, respectively) [21][22][23]. Furthermore, our estimates of cumulative incidence of varicella at age 11 years are similar to that of a recent independent French seroprevalence study (90 % at age 11 years [24]) as well as earlier figures in France [25].…”

Susceptibility of New Entrant University Students in Sri Lanka to Varicella Zoster Infection

“…This assumption was based on very high positive predictive values reported in a number of seroprevalence studies. [10][11][12][13][14][15][16][17][18] All students with a negative history of chicken pox were invited for serological testing. Those who volunteered for the test were given a full explanation of the study and written informed consent was obtained.…”