Hindawi Publishing Corporation Infectious Diseases in Obstetrics and Gynecology Volume 2013, Article ID 140142, 6 pages http://dx.doi.org/10.1155/2013/140142 Research Article Avidity of Antibodies against HSV-2 and Risk to Neonatal Transmission among Mexican Pregnant Women Antonia Herrera-Ortiz, 1 Carlos Jesús Conde-Glez, 2 Dayana Nicté Vergara-Ortega, 3 Santa García-Cisneros, 1 Ma. Leonidez Olamendi-Portugal, 1 and Miguel Angel Sánchez-Alemán 1 1 Centro de Investigaci´ on sobre Enfermedades Infecciosas, Instituto Nacional de Salud P´ ublica, Avenida Universidad No. 655, Colonia Santa Mar´ ıa Ahuacatitl´ an, Cerrada Los Pinos y Caminera, CP 62100, Cuernavaca, Morelos, Mexico 2 Centro de Investigaci´ on en Salud Poblacional, Instituto Nacional de Salud P´ ublica, Avenida Universidad No. 655, Colonia Santa Mar´ ıa Ahuacatitl´ an, Cerrada Los Pinos y Caminera, CP 62100, Cuernavaca, Morelos, Mexico 3 Universidad Polit´ ecnica del Estado de Morelos, Boulevard Cuauhn´ ahuac No. 566, Colonia Lomas del Texcal, CP 62550, Jiutepec, Morelos, Mexico Correspondence should be addressed to Miguel Angel S´ anchez-Alem´ an; msanchez@insp.mx Received 30 April 2013; Accepted 2 July 2013 Academic Editor: Lu-Yu Hwang Copyright © 2013 Antonia Herrera-Ortiz et al. his is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Objective. To determine HSV-2 seroprevalence, risk factors, and antibody avidity among a sample of Mexican pregnant women. Material and Methods. he avidity test was standardized with diferent urea concentrations and incubation times; the cut-of point was calculated to determine the low avidity (early infection). IgG antibodies against HSV-2 were detected from pregnant and postpartum women from Morelos, Mexico, and the avidity test was performed to positive samples. Multivariate regression logistic analysis was employed to evaluate demographic and sexual behavior characteristics associated with HSV-2 infection. Results. HSV- 2 seroprevalence among Mexican women analyzed was 14.5% (333/2300), demographic factors (location of General Hospital, age, education level, and civil status), and risky sexual behaviors (STI self-report and number of sexual partners during last year) were associated with HSV-2 infection. Seventeen women were detected with low avidity antibodies (early infection) with a cut-of point of 66.1%. Conclusions. HSV-2 infection was common among this group of women from Mexico; the avidity test detected women with recent infections, and these women were more likely to transmit HSV-2 to their neonates. Neonatal herpes has no epidemiological surveillance, the disease could be overlooked, and so more studies are needed to estimate the magnitude of neonatal infection. 1. Introduction Herpes Simplex Virus (HSV) belongs to Herpesviridae family and has four basic structures: core with DNA double strand, icosahedral capsid, tegument, and lipidic envelope, and also HSV presents two basic properties, latency and neuroviru- lence. HSV-1 can cause oral lesions, and HSV-2 is the prin- cipal agent of genital herpes and could cause recurrent ulcers but is asymptomatic in 80% of cases [1, 2]. Genital herpes is a frequent infection during pregnancy, one-ith of women have antibodies against HSV-2 [3], one- tenth of pregnant women infected with HSV-2 have genital viral shedding [4], and inally, 5% of women with genital viral shedding could transmit the infection to their neonates [5]. USA reported a neonatal herpes incidence of 31.25 for 100,000 newborns in Washington [5] and 13.3/100,000 in New York [6]. Vertical transmission leading to neonatal herpes virus infection may occur at vaginal delivery, which can cause congenital anomalies. Forty-ive percent of neonatal herpes cause the localized form in mouth, eyes, or skin; 30% of cases arise nervous system infections, with lethargy, convulsions, and loss of appetite, with or without skin lesions; the remain- ing 25% of neonatal herpes are associated with disseminated infection (clinically not diferent from bacterial sepsis); this type of neonatal form can afect lung, liver, and brain; the lethality is around 80% [6–10].