Gwendolyn L. Gilbert

Estimates of chronic hepatitis B virus infection in Australia, 2000.

Objectives: To estimate the prevalence of chronic hepatitis B virus (HBV) infection in Australia and attributable proportions associated with specific demographic groups at higher risk of infection.

Bacteriuria due to ureaplasmas and other fastidious organisms during pregnancy: prevalence and significance.

When urine, which has been collected by suprapubic bladder aspiration, is appropriately cultured, asymptomatic bacteriuria due to fastidious organisms can be detected quite commonly in apparently healthy pregnant women; Ureaplasma urealyticum and Gardnerella vaginalis can each be isolated from the bladder urine of 10 to 15% of subjects, other bacteria less frequently. Both organisms are often present together, sometimes in addition to conventional urinary pathogens. Overall bacteriuria occurs in about 25% of healthy pregnant women, including 6% with conventional asymptomatic bacteriuria. Pyuria occurs in about one-third of patients with fastidious bacteriuria. Bacteriuria due to fastidious bacteria occurs significantly more commonly in selected groups of pregnant women. U. urealyticum or G. vaginalis or both can be isolated, generally in relatively high numbers from more than 70% of pregnant women with renal disease and 20 to 30% of those with preeclampsia. In a prospective study in which urine was collected using an open ended catheter, ureaplasmas were isolated 3 times more frequently from women less than 25 years of age than from older women. Women with Ureaplasma bacteriuria at the first antenatal visit were 3 times more likely to develop preeclampsia than those without, but the mean birth weights of the infants born to the two groups of women were not significantly different. Further studies are required to determine the importance of these preliminary findings.

Prevention of Neonatal Group B Streptococcal Sepsis: Is Routine Antenatal Screening Appropriate

EDITORIAL COMMENT: This position paper has a senior team of authors from Departments of Microbiology and Infectious Diseases, Oncology and Paediatrics and carries the weight of the Paediatric Infectious Diseases Group of the Australasian Society for Infectious Diseases. This impressed but did not intimidate the editorial subcommittee and other reviewers of this article, who although recommending publication, wish to ask readers to consider the following points. Firstly, the authors do not include an obstetrician, and obstetricians do not favour routine screening for group B streptococcal carriage by vaginal and rectal swabbing because women do not like rectal swabbing. The result of introduction of routine vaginal and rectal swabbing at 26‐28 weeks gestation in the hospital where the editor works in an antenatal clinic was that the policy failed because of the rectal swabbing, with the result that vaginal swabs are now performed in less than 50% of patients attending the clinic, although it remains hospital policy for routine swabbing to be performed. Secondly, recommendations need to be dogmatic and precise if clinicians are to follow the favoured regimen. This paper has no clear statement of what constitutes ‘an epidemiological risk factor for infection’ in the women for whom intrapartum prophylaxis is recommended, nor is there a statement of the antibiotic regimens favoured. Moreover, there is no recommendation about antibiotic therapy for the infant. Our third concern is that the calculations in this paper and its tables are based on the assumption that the perinatal mortality rate from neonatal sepsis due to group B streptococcus is 20% of the 2 per 1,000 with neonatal sepsis due to this organism ‐ if. a death rate of 1 in 2,500 births.

Antibiotic management of pneumococcal infections in an era of increased resistance

Abstract: Pneumococci are a leading cause of bacterial meningitis and bacteraemia, as well as pneumonia, otitis media and sinusitis in childhood. These organisms recently have shown a dramatic increase in antibiotic resistance. Penicillin‐resistant pneumococci are of special concern as they are often resistant to other unrelated antibiotics. This is of particular significance to Aboriginal children who have among the highest rates of pneumococcal infection in the world. Laboratories should now test all invasive pneumococcal isolates for penicillin and third generation cephalosporin resistance. Local treatment guidelines are required for pneumococcal infections, especially for meningitis, taking into account the prevalence of resistant strains within the community. At present, penicillin and amoxycillin remain the drugs of choice for pneumococcal infections, with the exception of meningitis where initial empirical therapy must be with a third generation cephalosporin. Judicious antibiotic use, which avoids over‐prescribing and unnecessary use of broad‐spectrum agents, improved living standards in underprivileged communities and introduction of an effective conjugate vaccine, able to reduce the rates of pneumococcal infection and hopefully colonization, may limit the spread of resistant strains.

Isolation of genital mycoplasmas from the blood of neonates and women with pelvic infection using conventional SPS-free blood culture media

&NA; Standard blood culture media used in our laboratory were tested for their ability to support the growth of Mycoplasma hominis and Ureaplasma urealyticum. Small inocula (approximately 10 colony forming units per ml) of both organisms grew in diphasic tryptone soya medium but not in any of several media containing sodium polyanetholesulphonate (SPS) including a modified Schaedler broth (RWH anaerobic medium) and two BACTEC media (6B and 7D). Both organisms were inhibited even by very low concentrations of SPS but grew well in the Royal Womens Hospital (RWH) anaerobic medium when SPS was omitted. During a 22‐month period, routine “blind” plating of the aerobic blood cultures on to mycoplasma agar resulted in isolation of M. hominis or U. urealyticum from 12 women with postpartum or postoperative pelvic infection, and from 3 neonates. Genital mycoplasmas represented 35% of significant isolates from adult blood cultures.

Antenatal Screening for Congenital Infection with Rubella, Cytomegalovirus and Toxoplasma

Summary: The sera of 3,463 pregnant women were screened, at the first antenatal visit, for antibodies to rubella, cytomegalovirus (CMV) and Toxoplasma gondii. Rubella antibodies were detected in 97.5%, CMV antibodies in 71% and toxoplasma antibodies in 45% of women. Asymptomatic toxoplasmosis occurred during pregnancy in 3 of 609 (0.5%) and primary CMV infection in 5 of 338 (1.5%) initially seronegative women whose sera were retested at the end of their pregnancies. The observed incidence of toxoplasmosis was similar to that calculated on the basis of the age‐related prevalence of antibodies found in this study. On the basis of these observations it is estimated that congenital toxoplasmosis and congenital CMV infection due to primary maternal infection each occurs in up to 2/1,000 infants in this community. Very few of these infants have obvious abnormalities at birth, but follow‐up studies elsewhere have shown that many of them suffer significant long‐term sequelae.

Acyclovir for the prevention and treatment of varicella zoster in children, adolescents and pregnancy

Abstract: Varicella causes a mild, self‐limiting childhood disease that may reactivate years later as shingles. In immuno‐compromised patients with altered cell mediated immunity, and rarely in healthy individuals, varicella results in a life‐threatening infection. The antiviral drug, acyclovir, substantially reduces the mortality and risk of severe disease in these groups of patients. Early commencement of acyclovir is recommended for children with both varicella and altered cell mediated immunity, newborns during the first 2 weeks of life, preterm infants in the neonatal nursery, and severe varicella or shingles (including ocular zoster) in any patient, as well as during pregnancy. Acyclovir may be considered in children with serious cardiopulmonary disease or chronic skin disorders where varicella may exacerbate the underlying disease or increase the risk of secondary bacterial sepsis. Acyclovir, however, is not recommended for healthy individuals without severe disease, as a prophylactic agent against varicella, for asthmatics receiving aerosolized or low‐dose oral steroids and/or as treatment of the post‐varicella syndromes. When acyclovir is prescribed it should be given intravenously to those with severe disease, those at risk of dissemination and in children younger than 2 years of age.