Perinatal transmission of the human immunodeficiency virus.

Vertical transmission of human immunodeficiency virus (HIV) from an infected mother to her fetus or infant can occur in utero and probably during labor and delivery. Transmission via breast milk has also been documented. Because of limitations of conventional HIV testing in infants, it is difficult to determine the rate of transmission from an infected mother to her fetus or infant, but it is probably between 20% and 60%, depending on the mother's health status. Perinatal HIV infection is a significant problem particularly in "Pattern II" countries, where HIV is spread primarily by heterosexual contact. In "Pattern I" countries, where HIV predominantly affects homosexual and bisexual men, children are infected by mothers who acquired the infection through I.V. drug abuse or sexual contact with an infected partner.

[Infection of the newborn infant by the human immunodeficiency virus]. / L'infection du nouveau-né par le virus de l'immunodéficience humaine.

HIV infection of the newborn is now known to result mostly from mother-to-foetus transmission. The risk of transmission is at least 40 p. 100. However, the circumstances of passage are little known, and there is no maternal virological parameter capable of evaluating individual risks. The disease is more severe in children than in adults. Rare are the children who remain asymptomatic for more than 15 months; one out of three of them develop severe acquired immunodeficiency syndrome and die within the first 2 or 3 years of life. A specific encephalopathy is observed in about 30 p. 100 of the infected children. Kaposi's sarcoma is exceptional. Since there is no contagion between children, those who are in fairly good clinical condition should have a family and school life as normal as possible.

Chlamydia in women: a case for more action?

PIP: The 1985 Communicable Disease Surveillance Center figures for sexually transmitted diseases document over 14,000 confirmed cases of genital chlamydial infection in women. Yet, this figure seriously underestimates the size of the problem as many chlamydial infections are silent. The mainstay of diagnosis until recently has been isolation of C. trachomatis in cell culture, which is time consuming, technically demanding, expensive, and available in only a few centers. A firm diagnosis of chlamydial infection cannot be based on serology alone. Antibodies can be detected in 78-100% of womn with C. trachomatis in the cervix, but in those who are culture negative 31-87% also will have antibodies. More support is given to the diagnosis by demonstration of a rising titre of IgG antibody or by detection of IgM, but because of the late presentation of most women with chlamydia this is seldom possible. Newer tests include direct immunofluorescence statining of genital secretions which is rapid and simple. Results of this method compare favorably with those of cell culture, but screening large numbers of smears is expensive and tedious. Enzyme-linked immunosorbent assays also give good results. C trachomatis is a well known cause of cervicitis and salpingitis and is consequently a major factor in infertility. The frequency of chlamydial infection is influenced by sexual activity and promiscuity, but the effect of contraceptive choice is more difficult to determine. An IUD can provide a nidus for many infections, but the role of oral contraceptives (OCs) is more controversial. Instrumentation of the endocervical canal provides a route for introduction of infection, which is therefore a frequent and important complication of induced abortion. Westergaard et al. in a study of women having 1st trimester abortions found that 10% had symptomless cervical chlamydia; postabortal pelvic inflammatory disease developed in 28% of these patients by comparison with 10% in culture-negative women. Other workers have found similar results. The role of chlamydia as a cause of morbidity in pregnancy is unclear. Complications for the newborn are better established. It has been estimated that between 2-37% of mothers will have a chlamydia infection in pregancy. If 33-50% of newborns at risk get conjunctivitis, and 10-20% get pneumonitis, this gives some indication of the extent of the problem. Several studies have suggested an association between cervical chlamydial infection, anti-chlamydial antibodies, and cervical dysplasia. Emphasis on early diagnosis and treatment is of paramount importance to reduce the prevalence of chlamydial infection and its complications; without this rates of ectopic pregnancy and infertility are bound to increase.^ieng

CNS diseases associated with varicella zoster virus and herpes simplex virus infection. Pathogenesis and current therapy.

In recent years, herpes simplex virus has been recognized as an important CNS pathogen in neonates and adults. The recent development of effective antiviral therapy has substantially reduced the excessive morbidity and mortality associated with these infections. For neonatal herpes simplex infections, the current drug of choice is vidarabine. The results of ongoing clinical trials comparing vidarabine with acyclovir in neonatal herpes may lead to a change in the recommended therapy. In the adult, the therapy of choice for herpes simplex encephalitis is acyclovir. Although effective, the present therapies for herpes simplex infections of the CNS leave much room for improvement. In addition to the development of more effective antiviral drugs and less invasive diagnostic techniques, prevention of these often devastating infections will be important in reducing morbidity and mortality. The CNS diseases associated with varicella and herpes zoster may have a different pathogenesis. The implication for therapy in these diseases favors nonspecific supportive therapy in the varicella-associated syndromes. The few anecdotal reports of the use of vidarabine and acyclovir in herpes zoster encephalitis and the histopathologic evidence suggesting viral invasion of the CNS in many cases of zoster-associated neurologic syndromes makes the use of specific antiviral therapy in zoster encephalomyelitis more rational. However, appropriate therapeutic recommendations will have to be based on controlled clinical trials that have not yet been performed.

Neonatal cytomegalovirus infections due to blood.

Infants with very low birthweights (less than 1250g) are immunocompromised and have immature hematopoietic systems. They require frequent blood transfusions and have an increased susceptibility to infection. These very low birthweight infants who lack passively acquired antibody against CMV, acquire transfusion-associated CMV infections with a frequency of approximately 30%. These infections are associated with significant morbidity and mortality. The source of these postnatally acquired CMV infections are seropositive blood donors. These infections can be prevented by appropriate donor selection and/or blood processing. Recent but limited data suggests that all infants (regardless of birthweight or the presence of antibody against CMV) should receive CMV seronegative blood products if they are likely to receive multiple transfusions from multiple donors.

Detection of group B streptococci by agglutination testing from selective broth cultures.

A rapid technique for the immunological identification of group B streptococci in vaginal swabs is reported. Vaginal swabs obtained from 567 pregnant women at term or during labor were incubated for eight hrs in Todd Hewitt broth containing 15 micrograms per ml nalidixic acid, one microgram per ml polymixin, and 0.1 microgram per ml crystal violet (NPC broth). After streaking the swabs on blood agar plates, both plain broth cultures and their nitrous acid extracted pellets were tested with a commercial latex agglutination reagent. Beta-hemolytic colonies grown on the blood agar plates after overnight incubation were grouped with commercial latex agglutination and coagglutination reagents for reference identification. Sensitivities for the broth culture and nitrous acid techniques were 86.8 percent and 94.7 percent, respectively; specificities were 97.4 percent and 98.7 percent respectively. Nitrous acid extraction of vaginal broth cultures followed by latex agglutination testing can significantly shorten the time needed to detect group B streptococci, resulting in the intrapartum detection of these organisms.

Prevalence of cytomegalovirus antibodies in obstetric nurses. A study in a specialist metropolitan teaching hospital.

The prevalence of antibodies to cytomegaloviruses (CMV) in applicants for nursing staff appointments was shown to be significantly lower than that reported earlier in obstetric patients of the same metropolitan area. Age and previous nursing experience with midwifery patients or neonates were found to be significant factors associated with the prevalence of antibodies to CMV in staff applicants. Student midwives younger than 25 years were the group most susceptible to primary CMV infection. The duties that seronegative pregnant staff members or those planning pregnancy at an early date should be allowed to carry out are discussed. The importance of hygiene in the prevention of nosocomial infections, and of the skin care of hands subjected to frequent washing, is stressed.

Sexually transmitted diseases and pregnancy.

The association of adverse pregnancy outcome with Treponema pallidum, Neisseria gonorrhoeae and herpes simplex infections is well known and specific recommendations for management have been formulated. However, other agents that are not so well known can be transmitted sexually and threaten an otherwise healthy pregnancy. These agents are discussed in order to make the nurse more aware of related maternal and fetal diseases.

Epidemiology of group B streptococci: one year's experience in an obstetric and special care baby unit.

The epidemiology of group B streptococci (GBS) was studied in an obstetric unit and the related special care baby unit (SCBU). In 1 year 53 (77%) of 69 babies who acquired GBS from their mothers were colonized within 24 h of birth, compared with only 9 (35%) of 38 who acquired GBS from non-maternal sources. While 38 (36%) of 107 GBS colonized babies in the obstetric unit derived the organism from a non-maternal source, the value for the SCBU was only 2 (9%) of 23. In babies rectal and umbilical swabs gave the highest GBS isolation rates. Phage-typing and serotyping suggested that colonized mother baby pairs, rather than staff, were the primary source of hospital acquired GBS. This mode of GBS acquisition did not result in long-term carriage once babies had left hospital. Nosocomial transmission can play an important part in GBS epidemiology, but can be minimized by attention to infection control procedures.