摘要:

Essentially all new cases of human immuno-deficiency virus (HIV) infection in infants and young children occur as a consequence of exposure to HIV eitherin utero, intrapartum or postpartum during breast feeding. Currently it is estimated that the majority of vertical transmission of HIV occurs at or near the time of birth. Based on what is known about the biology of perinatal HIV transmission, the HIV burden of the mother, effectiveness of her immune response and that of her fetus/infant and the integrity of the placental “barrier” are likely to play important roles in this process. The role of impaired immunologic control of HIV is gaining recognition as a potential key element in the pathophysiology of perinatal HIV transmission. In most studies to date, advanced maternal disease and low CD4 lymphocyte count have been associated with increased risk of vertical HIV transmission. In addition some studies have indicated that low maternal titers of antibodies to certain V3 loop epitopes may have a similar effect on vertical transmission. Cellular immune responses, which are known to play an important role in host defense against HIV, appear to be impaired in infants after exposure to HIV, especially those responses involving the development of cytotoxic lymphocytes. Mounting evidence suggests that enhancement of humoral and/or cellular immune responses in pregnant women and exposed infants is a logical and potentially feasible approach to interruption of perinatal transmission (an approach similar to that utilized for perinatally acquired hepatitis B virus infection). Studies are now in progress to assess HIV hyperimmune globulin and envelope HIV vaccines in pregnant woman and HIV-exposed infants.

ISSN:0891-3668    

出版商:OVID    

年代:1994

数据来源: OVID

摘要:

Respiratory syncytial virus (RSV) is responsible for serious respiratory disease in young infants. More than 75% of the 678 children hospitalized for RSV at Baylor-affiliated hospitals in Houston, TX, between October 1992, and March, 1993, were 5 months of age or younger. The importance of maternal antibody in the immunity against RSV disease has been debated. More recent epidemiologic studies have demonstrated protection against RSV in babies born to mothers with high levels of neutralizing RSV antibody. The contribution of IgC fusion or F protein antibody as a correlate with immunity from disease also has been described. With the availability of purified F protein vaccines such as the purified F protein vaccines manufactured by Lederle-Praxis-Biologeals (Pearl River, NY), immunization of pregnant women with RSV surface glycoproteins to arm the newborn with high neutralizing antibody can be considered. Advantages of maternal immunization to augment naturally occurring maternal RSV antibody are that babies most at risk for infection are least responsive to vaccines, that pregnant women respond well immunologically to vacciaes in general and that placental transfer of maternal IgG antibody occurs naturally during the third trimester. The safety of maternally derived antibody would likely surpass that of exogenously administered immunoglobulin as well as would have a decreased cost. Disadvantages of maternal immunization to protect infants against RSV could include the potential inhibition of the infant's response to active immunization or subsequent disease, the lack of antibody transfer in premature infants, and liability issues. Evaluation of purified F protein vaccine in postpartum women is under way.

ISSN:0891-3668    

出版商:OVID    

年代:1994

数据来源: OVID

摘要:

Respiratory syncytial virus (RSV) is the only viral respiratory pathogen that produces an annual epidemic of respiratory illness. Infants with cardiac disease or infants born prematurely with or without bronchopulmonary dysplasia are at increased risk of severe RSV disease. A recently developed RSV immunoglobulin (RSVIG) was studied to determine safety and efficacy in prevention of severe RSV disease in such children who are high risk for severe RSV illness. Results from this prospective, blinded trial involving 249 children (102 with bronchopulmonary dysplasia, 87 with congenital heart disease and 60 who were born prematurely) indicate that high dose RSVIG

ISSN:0891-3668    

出版商:OVID    

年代:1994

数据来源: OVID