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Sensitive detection methods, such as DNA PCR and RNA PCR suggest that vertical transmission of human immunodeficiency virus (HIV) occurs at three major time periods; in utero, around the time of birth, and postpartum as a result of breastfeeding (Fig. 1). Detection of proviral DNA in infant's blood at birth suggests that transmission occurred prior to delivery. A working definition for time of infection is that HIV detection by DNA PCR in the first 48 h of life indicates in utero transmission, while peripartum transmission is considered if DNA PCR is negative the first 48 h, but then it is positive 7 or more days later [1]. Generally, in the breastfeeding population, breast milk transmission is thought to occur if virus is not detected by PCR at 3–5 months of life but is detected thereafter within the breastfeeding period [2]. Using these definitions and guidelines, studies has suggested that in developed countries the majority, or two thirds of vertical transmission occur peripartum, and one-third in utero [3–6]. The low rate of breastfeeding transmission is due to the practice of advising known HIV-positive mothers not to feed breast milk. However, since the implementation of antiretroviral treatment in prophylaxis of HIV-positive mothers, some studies have suggested that in utero infection accounts for a larger percentage of vertical transmissions [7]. In developing countries, although the majority of infections occurs also peripartum, a significant percentage, 10–17%, is thought to be due to breastfeeding [2, 8, 9].

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Acta Veterinaria Hungarica
Authors:
Fumina Sasaoka
,
Jin Suzuki
,
Toh-Ichi Hirata
,
Toshihiro Ichijo
,
Kazuhisa Furuhama
,
Ryô Harasawa
, and
Hiroshi Satoh

The vertical transmission of Mycoplasma (M.) wenyonii was investigated in beef cattle raised on a farm in Japan by analysing the ribonuclease P RNA (rnpB) gene sequence using PCR. Peripheral blood samples from 17 dams infected with M. wenyonii and from their neonatal calves were collected and colostrum samples were taken from cows immediately after parturition, and subsequently the blood samples of calves were monitored continuously for three months. At birth on day 0, although no rnpB gene was detected in the colostrum of any of the dams, four (23.5%) of the 17 calves born were positive. At three months after delivery, the number of positive calves decreased to three. Although horizontal transmission by blood-feeding arthropod vectors has been basically accepted as the most common route of haemoplasma infection, these findings suggest that vertical transmission is, at least in part, another most likely route of M. wenyonii infection in cattle.

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transmission. J. Med. Virol., 2006, 78 , 911–914. Moriondo M. Alanine transaminase levels in the year before pregnancy predict the risk of hepatitis C virus vertical transmission

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Indolfi, G., Azzari, C., Moriondo, M. és mtsai: Alanine transaminase levels in the year before pregnancy predict the risk of hepatitis C virus vertical transmission. J. Med. Virol., 2006, 78 , 911

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Abstract

Primary and recurrent infections of human cytomegalovirus (HCMV) can occur during pregnancy. Both can result in congenital infection, the leading infectious cause of mental retardation, sensorineural deafness and visual impairment. The intrauterine transmission of HCMV and an adverse outcome are mainly related to a primary maternal infection. However, there is currently increasing evidence that the incidence of symptomatic infections in infants born to immune mothers is higher than previously thought. The option of a prenatal diagnosis therefore has a crucial role in the management of pregnancies complicated by active HCMV infection. In spite of the potentially devastating consequences of congenital HCMV infection, little information is available concerning antiviral therapy as prophylactic treatment for women at high risk of the transmission of HCMV during pregnancy. Passive immunization for the prevention of vertical transmission of the virus appears promising. Until a HCMV vaccine is available, education is needed regarding the risk involved and the strategies to be adopted for the prevention of HCMV infection during pregnancy.

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Absztrakt

A várandós anyák primer és rekurrens humán cytomegalovirus- (HCMV-) fertőzéséhez társulhat a magzat fertőzése. A HCMV a congenitalis fertőzések leggyakoribb okozója, amelynek legsúlyosabb következményei a szellemi visszamaradottság, progrediáló halláskárosodás, látászavarok. Az anya primer fertőzését követi leggyakrabban a magzat fertőzése, és a magzat károsodásai rendszerint súlyosak. Növekszik az anyai rekurrens fertőzések után jelentkező, különböző súlyosságú tünetekkel járó congenitalis HCMV-fertőzések száma. Az aktív HCMV-fertőzéssel komplikált terhességek gondozásában döntő szerepet játszik a praenatalis diagnosztika. A congenitalis HCMV-fertőzés potenciálisan súlyos következményei ellenére kevés adat áll rendelkezésünkre a HCMV vertikális terjedésének antivirális gyógyszerrel történő megelőzésére, de a passzív immunizálással biztató eredmények vannak. Vakcina hiányában is elkerülhető a várandós anyák aktív HCMV-fertőzése, ha felhívjuk a figyelmet a fertőzés veszélyeire és ismertetjük a fertőzés megelőzésének lehetőségeit.

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Congenital human cytomegalovirus (CMV) infection is the leading infectious cause of mental retardation, sensorineural deafness and visual impairment. It is mainly related to a primary maternal infection. The placenta should be considered the most important site of both the protection of the fetus from CMV infection and the transmission of CMV from mother to fetus. The control of the passage of CMV across the placenta probably involves a cascade of regulatory events. Roles are played by factors relating to the host immune-selective pressures, such as local cytokines and maternal CMV-specific neutralizing antibodies. The presence of other pathogens at the maternal-fetal interface also influences the outcome of CMV infection. Further investigations are needed in which clinical CMV strains are applied in in vitro studies to unravel the molecular mechanism of the intrauterine transmission of CMV and to elucidate the complex regulation that leads to prevention of the in utero transmission of CMV in vivo.

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The acquired immunodeficiency syndrome (AIDS), which is caused by the human immunodeficiency virus (HIV), was first described in the United States of America in 1981 [1]. The worldwide spread of HIV has soon been recognized and AIDS has become one of the most alarming infectious diseases of our days. Its impact has been tremendous, high morbidity and mortality has caused a reversal of socioeconomic gains previously recorded in several developing countries, especially those in Sub-Saharan Africa [2]. Epidemiological data about the HIV and AIDS pandemic are updated by the Joint United Nation Programme on HIV/AIDS, UNAIDS (http://www.unaids.org). Their latest report from December 2000 states that in year 2000 approximately 5.3 million people have become newly infected with HIV, of which 2.2 were women and 600 000 children younger than 15 years of age. The estimated number of people living with HIV/AIDS globally is 36.1 million, of which 16.4 million are women and 1.4 million are children younger than 15 years of age. Approximately 25.3 million (70%) of these HIV infected people live in Sub-Saharan Africa, 5.8 million in South- and South-East Asia (15%), and 1.4 million in Latin-America (5%). During year 2000, 3 million people died of AIDS (1.3 million women and 500 000 children younger than 15 years of age). This means that an estimated total of 21.8 million persons have died of AIDS since the beginning of the epidemic, including 4.3 million children younger than 15 years of age.

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Acta Veterinaria Hungarica
Authors:
Joan Tutusaus
,
Fernando López-Gatius
,
Sonia Almería
,
Beatriz Serrano
,
Eva Monleón
,
Juan José Badiola
, and
Irina García-Ispierto

Samples from 45 dams (milk/colostrum, faeces, vaginal fluid and blood on days 171–177 of gestation and at parturition, and cotyledons at parturition) and their calves (blood collected before colostrum intake and weekly until days 29–35) were analysed to examine the vertical transmission of Coxiella burnetii and links between shedding and seropositivity. All calves were born C. burnetii seronegative. Only those born to seropositive dams seroconverted following colostrum intake. Logistic regression analyses indicated that the likelihood of dam seropositivity was 21 and 4.85 times higher for multiparous than for primiparous (65.6% vs. 8.3%, P = 0.006) and for prepartum shedding cows (75% vs. 38.2%, P = 0.03) compared to the remaining animals, respectively. In conclusion, the results of this study indicate no detectable precolostral antibody response in calves born from dams with cotyledons positive for C. burnetii by qPCR. In order to analyse the possibility of persistent infection due to immunotolerance to an early in utero infection, further studies will need to test for C. burnetii DNA. In addition, in the present study multiparous cows showed a significantly higher seroprevalence than primiparous cows and heifers, colostral antibodies were efficiently transferred to newborn calves, and there was a link between bacterial shedding on days 171–177 of gestation and Coxiella seropositivity of the dam.

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Porcine circovirus type 2- (PCV2-) associated reproductive disorders and enteritis have commonly been observed on PCV2-contaminated pig farms in recent years. In order to investigate disorders of intestinal immunity in piglets infected by PCV2 during the fetal period, 9 PCV2b-infected piglets and 6 non-infected piglets at one day of age were selected and euthanised prior to suckling. Samples of mesenteric lymph nodes (MLNs) and duodena were collected to investigate factors related to intestinal immunity and to detect lymphocytic apoptosis. The results indicated that there were no significant changes in the levels of IL-2, IL-10 and transforming growth factor-β (TGF-β) in the PCV2b-infected piglets but IFN-γ levels were significantly lower (P < 0.01) and IL-4 levels were significantly higher (P < 0.05) in infected piglets than in the controls. Furthermore, lymphocytic apoptosis increased in PCV2b-infected piglets and CD4+ to CD8+ ratios were lower in these piglets than in the controls. These findings suggest vertical transmission of PCV2b to fetuses, leading to an imbalance of intestinal immune function in piglets.

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