Sheila C. Dollard

A universal screening research study was conducted in six hospitals to identify the clinical sensitivity of polymerase chain reaction (PCR) testing on newborn dried blood spots (DBSs) versus saliva specimens for the diagnosis of congenital cytomegalovirus (cCMV). CMV DNA positive results from DBSs or saliva were confirmed with urine testing. Findings of several false-positive (FP) saliva PCR results prompted an examination of a possible association with donor milk. Documentation of the frequency of positive saliva results, including both true-positive (TP) and FP status from clinical confirmation, occurred. The frequency of donor milk use was compared for TP and FP cases. Of 22,079 participants tested between 2016 and 2022, 96 had positive saliva results, 15 were determined to be FP, 79 TP, and 2 were excluded for incomplete clinical evaluation. Newborn donor milk use was identified for 18 (19.14%) of all the positive saliva screens. Among the 15 FPs, 11 (73.33%) consumed donor milk compared to 7 of the 79 TPs (8.8%) (OR 28.29, 95% CI 7.10–112.73, p < 0.001). While milk bank Holder pasteurization inactivates CMV infectivity, CMV DNA may still be detectable. Due to this possible association, screening programs that undertake testing saliva for CMV DNA may benefit from documenting donor milk use as a potential increased risk for FP results.

The clinical presentation of varicella in unvaccinated persons, with skin vesicles and scabs, has facilitated the use of rapid diagnostic methods for confirming disease. Polymerase chain reaction (PCR) assays are the diagnostic method of choice. The sharp decline in unmodified cases of varicella due to the US varicella vaccination program has led to fewer healthcare providers being familiar with varicella presentation and an increased reliance on laboratory diagnosis to confirm suspected cases. The mild, atypical presentation of the disease in vaccinated persons (fewer skin lesions, mostly maculopapular) has made it more challenging for providers to recognize and also to collect samples to detect the virus. Nonetheless, PCR is highly sensitive and specific in confirming modified disease if adequate samples are provided. While a positive PCR result is confirmatory, interpreting a negative result can prove to be more challenging in determining whether suspected varicella is falsely negative or attributable to other causes. Enhanced education of healthcare providers is critical for adequate specimen collection from modified varicella cases. In addition, more sensitive commercial serologic assays are needed in the United States for varicella immunity testing in the vaccine era.

Urine is the best specimen for the diagnosis of congenital cytomegalovirus, but collection and processing of liquid urine are impractical for screening. Urine dried on filter paper was processed by the same convenient, low-cost method used by newborn screening to test blood spots and showed high sensitivity and specificity.

Congenital cytomegalovirus (cCMV), with an estimated birth prevalence of 4.5 per 1000 live births,¹ is the most common congenital viral infection in the United States but remains underrecognized. Long-term outcomes associated with cCMV include sensorineural hearing loss, intellectual disability, cerebral palsy, seizure disorders, and learning delays that may develop in up to 20% of all infected children.^2,3 Given the burden associated with cCMV and the proven benefits of treatment and early intervention for some affected infants,^4,5 there has been growing interest in universal newborn screening.⁶

We assessed maternal and infant cytomegalovirus (CMV) infection in Colombia. Maternal serum was tested for CMV immunoglobulin G antibodies at a median of 10 (interquartile range: 8–12) weeks gestation (n = 1501). CMV DNA polymerase chain reaction was performed on infant urine to diagnose congenital (≤21 days of life) and postnatal (>21 days) infection. Maternal CMV seroprevalence was 98.1% (95% confidence interval [CI]: 97.5%–98.8%). Congenital CMV prevalence was 8.4 (95% CI: 3.9%–18.3%; 6/711) per 1000 live births. Among 472 infants without confirmed congenital CMV infection subsequently tested at age 6 months, 258 (54.7%, 95% CI: 50.2%–59.1%) had postnatal infection.

Caring for young children is a known risk factor for cytomegalovirus (CMV) infection mainly through exposure to their saliva and urine. In a previous study, 36 CMV-seropositive children 2 mo. to 4 years old were categorized as CMV shedders (n = 23) or non-shedders (n = 13) based on detection of CMV DNA in their saliva and urine. The current study evaluated the presence of CMV on surfaces in homes of the children. Study staff made 4 visits to homes of the 36 enrolled children over 100 days. Saliva was collected by swabbing the mouth and urine was collected on filter paper inserted into diapers. In addition, five surface specimens were collected: three in contact with children’s saliva (spoon, child’s cheek, washcloth) and two in contact with children’s urine (diaper changing table, mother’s hand). Samples were tested by PCR and viral culture to quantify the presence of CMV DNA and viable virus. A total of 654 surface samples from 36 homes were tested; 136 were CMV DNA positive, 122 of which (90%) were in homes of the children shedding CMV (p < 0.001). Saliva–associated samples were more often CMV positive with higher viral loads than urine-associated samples. The higher the CMV viral load of the child in the home, the more home surfaces that were PCR positive (p = 0.01) and viral culture positive (p = 0.05). The main source for CMV on surfaces in homes was saliva from the child in the home. Higher CMV viral loads shed by children correlated with more viable virus on surfaces which could potentially contribute to viral transmission.

Background: Other than Kaposi sarcoma (KS)–associated herpesvirus and CD4⁺ T-cell lymphopenia, the mechanisms responsible for KS in the context of HIV are poorly understood. One recently explored pathway of HIV pathogenesis involves induction of the enzyme indoleamine 2,3-dioxygenase-1 (IDO), which catabolizes tryptophan into kynurenine and several other immunologically active metabolites that suppress T-cell proliferation. We investigated the role of IDO in the development of KS in HIV disease. Methods: In a case–control study among untreated HIV-infected Ugandans, cases were adults with KS and controls were without KS. IDO activity was assessed by the ratio of plasma kynurenine to tryptophan levels (KT ratio), measured by liquid chromatography–tandem mass spectrometry. Results: We studied 631 HIV-infected subjects: 222 KS cases and 409 controls. Non-KS controls had a higher median plasma KT ratio (130, interquartile range: 90 to 190 nM/μM) than KS cases (110, interquartile range: 90 to 150 nM/μM) (P = 0.004). After adjustment for age, sex, CD4 count, and plasma HIV RNA level, subjects with the highest (fourth quartile) plasma KT ratios had a 59% reduction (95% confidence interval: 27% to 77%) in the odds of KS compared with those with the lowest (first quartile) levels. KS was also independently associated with lower CD4⁺ count, higher plasma HIV RNA, and men. Conclusions: Among HIV-infected individuals, greater activity of the kynurenine pathway of tryptophan catabolism, as evidenced by higher levels of plasma KT ratio, was associated with lower occurrence of KS. Some consequences of immune activation in HIV infection might actually suppress certain cancers.

To better understand potential transmission risks from contact with the body fluids of children, we monitored the presence and amount of CMV shedding over time in healthy CMV-seropositive children. Through screening we identified 36 children from the Atlanta, Georgia area who were CMV-seropositive, including 23 who were shedding CMV at the time of screening. Each child received 12 weekly in-home visits at which field workers collected saliva and urine. During the final two weeks, parents also collected saliva and urine daily. Prevalence of shedding was highly correlated with initial shedding status: children shedding at the screening visit had CMV DNA in 84% of follow-up saliva specimens (455/543) and 28% of follow-up urine specimens (151/539); those not shedding at the screening visit had CMV DNA in 16% of follow-up saliva specimens (47/303) and 5% of follow-up urine specimens (16/305). Among positive specimens we found median viral loads of 82,900 copies/mL in saliva and 34,730 copies/mL in urine (P = 0.01), while the viral load for the 75th percentile was nearly 1.5 million copies/mL for saliva compared to 86,800 copies/mL for urine. Younger age was significantly associated with higher viral loads, especially for saliva (P < 0.001). Shedding prevalence and viral loads were relatively stable over time. All children who were shedding at the screening visit were still shedding at least some days during weeks 11 and 12, and median and mean viral loads did not change substantially over time. Healthy CMV-seropositive children can shed CMV for months at high, relatively stable levels. These data suggest that behavioral prevention messages need to address transmission via both saliva and urine, but also need to be informed by the potentially higher risks posed by saliva and by exposures to younger children.