Concurrent detection of other respiratory viruses in children shedding viable human respiratory syncytial virus.

Human respiratory syncytial virus (HRSV) is an important cause of respiratory disease. The majority of studies addressing the importance of virus co-infections to the HRSV-disease have been based on the detection of HRSV by RT-PCR, which may not distinguish current replication from prolonged shedding of remnant RNA from previous HRSV infections. To assess whether co-detections of other common respiratory viruses are associated with increased severity of HRSV illnesses from patients who were shedding viable-HRSV, nasopharyngeal aspirates from children younger than 5 years who sought medical care for respiratory infections in Ribeirão Preto (Brazil) were tested for HRSV by immunofluorescence, RT-PCR and virus isolation in cell culture. All samples with viable-HRSV were tested further by PCR for other respiratory viruses. HRSV-disease severity was assessed by a clinical score scale. A total of 266 samples from 247 children were collected and 111 (42%) were HRSV-positive. HRSV was isolated from 70 (63%), and 52 (74%) of them were positive for at least one additional virus. HRSV-positive diseases were more severe than HRSV-negative ones, but there was no difference in disease severity between patients with viable-HRSV and those HRSV-positives by RT-PCR. Co-detection of other viruses did not correlate with increased disease severity. HRSV isolation in cell culture does not seem to be superior to RT-PCR to distinguish infections associated with HRSV replication in studies of clinical impact of HRSV. A high rate of co-detection of other respiratory viruses was found in samples with viable-HRSV, but this was not associated with more severe HRSV infection.

Occurrence and severity of infections caused by subgroup A and B respiratory syncytial virus in children in southeast Brazil.

The frequency and severity of infections caused by respiratory syncytial virus (RSV) were assessed in children <2 years of age seen at the emergency department. The frequency of RSV detection in the clinical virology laboratory during the past 3 years was also analyzed retrospectively. RSV was found in 21.6% (188/869) of the samples collected from children seen at the emergency department and was found to be more frequent during the autumn, being less frequent or negligible by midwinter. RSV subgroups A and B co-circulated within the same time period in children seen at the emergency department, with varying predominance of either subgroup. There was no significant association of RSV subgroup with disease severity, but only a trend for RSV subgroup B being more frequent in children with risk factors for severe disease.

Predicting perinatal HIV infection in young Brazilian infants: How accurate are signs, symptoms and immunological abnormalities?

Early identification of infants perinatally infected with HIV (HIV+) requires costly laboratory tests which are not widely available in countries with limited resources. We evaluated the utility of detection of non-specific HIV-related signs and symptoms and immunological abnormalities in the diagnosis of perinatal HIV infection in Brazilian infants younger than 10 months of age and followed from birth. A total of 27 HIV+ and 43 uninfected infants were studied. All infants exhibited one or more non-specific HIV-related findings at least once. HIV+ infants were more frequently symptomatic than HIV- infants only when older than 3 months. Combinations of clinical and immunological findings resulted in high sensitivity (85-100%) and low specificity (25-65%) rates for the diagnosis of HIV infection. Conversely, low CD4+ cell counts and hyperimmunoglobulinaemia showed low sensitivity (52%) and high specificity (100%) rates. In conclusion, the detection of similar findings in HIV- and HIV+ infants underscores the need of early confirmatory laboratory testing.

Congenital and perinatal cytomegalovirus infection in infants born to mothers infected with human immunodeficiency virus.

OBJECTIVES: To determine the rates of congenital and perinatal cytomegalovirus (CMV) infection among infants born to mothers infected with HIV compared with infants born to mothers not infected with HIV from a CMV-immune, low-income population. STUDY DESIGN: A total of 325 newborns from CMV-seropositive mothers were enrolled and evaluated for congenital CMV infection (150 infants from HIV+ mothers and 175 infants from HIV- mothers. A total of 101 infants from HIV+ mothers and 33 infants from HIV- mothers were evaluated for perinatal CMV infection. The virus was isolated from urine by culture in human fibroblasts and was detected by polymerase chain reaction at birth and at 15 days and 12 weeks of age. RESULTS: Only 13 of 150 HIV+ mothers (8.7%) had an AIDS-defining condition, and none had a late-stage HIV infection. Congenital CMV infection was detected in 4 of 150 (2.7%) infants from HIV+ mothers and in 5 of 175 (2.9%) infants from HIV- mothers (p = 1.00). Perinatal CMV infection was diagnosed in 8 of 101 (7.9%) infants from HIV+ mothers and in 13 of 33 (39.4%) infants from HIV- mothers (p < 0.00001). Most infants (93.9%) from HIV- mothers and only 5.9% of infants from HIV+ mothers were breastfed. CONCLUSIONS: CMV coinfection in mothers without advanced HIV disease from a CMV-immune population does not enhance the likelihood of congenital CMV infection. Perinatal CMV transmission from HIV-infected mothers may be decreased by avoiding breastfeeding. Further studies on mothers with late-stage HIV infection are needed.