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Pneumocystis jirovecii is the most common cause of fungal pneumonia in children under the age of 2 years. However, the inability to culture and propagate this organism has hampered the acquisition of a fungal genome as well as the development of recombinant antigens to conduct seroprevalence studies. In this study, we performed proteomics on Pneumocystis-infected mice and used the recent P. murina and P. jirovecii genomes to prioritize antigens for recombinant protein expression. We focused on a fungal glucanase due to its conservation among fungal species. We found evidence of maternal IgG to this antigen, followed by a nadir in pediatric samples between 1 and 3 months of age, followed by an increase in prevalence over time consistent with the known epidemiology of Pneumocystis exposure. Moreover, there was a strong concordance of anti-glucanase responses and IgG against another Pneumocystis antigen, PNEG_01454. Taken together, these antigens may be useful tools for Pneumocystis seroprevalence and seroconversion studies.

SUMMARYSARS-CoV-2 infection causes a spectrum of clinical outcomes and diverse memory responses. Population studies indicate that viral neutralizing antibody responses are protective, but do not always develop post-infection. Other antiviral antibody effector functions, T-cell responses, or immunity to seasonal coronaviruses (OC43, 229E) have been implicated but not defined in all ages. Here, we identify that children and adult subjects generate polyfunctional antibodies to the spike protein after asymptomatic infection or mild disease, with some subjects developing cellular responses without seroconversion. Diversity in immunity was explained by two clusters distinguished by CD4+ T-cell cytokines, age, and antibodies to seasonal coronaviruses. Post-vaccination neutralizing responses were predicted by specific post-infection immune measures, including IL-2, spike-IgA, OC43-IgG1, 229E-IgM. We confirm a key role for CD4+ T cell cytokines in functionality of anti-spike antibodies, and show that antibody diversity is impacted by age, Th/Th2 cytokine biases, and antibody isotypes to SARS-CoV-2 and seasonal coronaviruses.

Serologic testing of residual blood samples from 812 children from a hospital in New Orleans, LA, between March and May 2020, demonstrated a SARS-CoV-2 seroprevalence of 6.8% based on S and N protein IgG; Black and Hispanic children, and children living in zip codes with lower household incomes were over-represented.

BACKGROUND: Circulating severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) RNA may represent a more reliable indicator of infection than nasal RNA, but quantitative reverse transcription PCR (RT-qPCR) lacks diagnostic sensitivity for blood samples. METHODS: A CRISPR-augmented RT-PCR assay that sensitively detects SARS-CoV-2 RNA was employed to analyze viral RNA kinetics in longitudinal plasma samples from nonhuman primates (NHPs) after virus exposure; to evaluate the utility of blood SARS-CoV-2 RNA detection for coronavirus disease 2019 (COVID-19) diagnosis in adults cases confirmed by nasal/nasopharyngeal swab RT-PCR results; and to identify suspected COVID-19 cases in pediatric and at-risk adult populations with negative nasal swab RT-qPCR results. All blood samples were analyzed by RT-qPCR to allow direct comparisons. RESULTS: CRISPR-augmented RT-PCR consistently detected SARS-CoV-2 RNA in the plasma of experimentally infected NHPs from 1 to 28 days after infection, and these increases preceded and correlated with rectal swab viral RNA increases. In a patient cohort (n = 159), this blood-based assay demonstrated 91.2% diagnostic sensitivity and 99.2% diagnostic specificity versus a comparator RT-qPCR nasal/nasopharyngeal test, whereas RT-qPCR exhibited 44.1% diagnostic sensitivity and 100% specificity for the same blood samples. This CRISPR-augmented RT-PCR assay also accurately identified patients with COVID-19 using one or more negative nasal swab RT-qPCR results. CONCLUSION: Results of this study indicate that sensitive detection of SARS-CoV-2 RNA in blood by CRISPR-augmented RT-PCR permits accurate COVID-19 diagnosis, and can detect COVID-19 cases with transient or negative nasal swab RT-qPCR results, suggesting that this approach could improve COVID-19 diagnosis and the evaluation of SARS-CoV-2 infection clearance, and predict the severity of infection. TRIAL REGISTRATION: ClinicalTrials.gov. NCT04358211. FUNDING: Department of Defense, National Institute of Allergy and Infectious Diseases, National Institute of Child Health and Human Development, and the National Center for Research Resources.

BACKGROUNDChildren (≤18 years) account for ∼20% of the US population but currently represent METHODSDuring the March 18th-May 15th 2020 Louisiana Stay At Home Order, 1690 blood samples from 812 individuals from a Children’s Hospital were tested for antibodies to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike protein. Demographics, COVID-19 testing, and clinical presentation abstracted from medical records were compared with local COVID-19 cases.RESULTSIn total, 62 subjects (7.6%) were found to be seropositive. The median age was 11 years with 50.4% female. The presenting complaint of seropositive patients was chronic illness (43.5%). Only 18.2% had a previous positive COVID-19 PCR or antibody test. Seropositivity was significantly associated with parish (counties), race, and residence in a low-income area. Importantly, seropositivity was linearly correlated with cumulative COVID-19 case number for all ages by parish.CONCLUSIONIn a large retrospective study, the seropositivity prevalence for SARS-CoV-2 in children in Louisiana during the mandated Stay At Home Order was 7.6%. Residence location, race, and lower socioeconomic factors were linked to more frequent seropositivity in children and correlated to regional COVID-19 case rates. Thus, a significant number of children in Louisiana had SARS-CoV-2 infections that went undetected and unreported and may have contributed to virus transmission.

1. Monika L. Dietrich, MD* 2. Russell W. Steele, MD†,‡ 1. *Department of Pediatrics, Tulane University School of Medicine, New Orleans, LA 2. †Department of Pediatrics, Ochsner Health Center for Children, New Orleans, LA 3. ‡University of Queensland School of Medicine, Ochsner Clinical School, New Orleans, LA * Abbreviations: ANF: : acute necrotizing fasciitis ARF: : acute rheumatic fever GAS: : group A Streptococcus IVIG: : intravenous immunoglobulin MRSA: : methicillin-resistant Staphylococcus aureus MSSA: : methicillin-susceptible S aureus PANDAS: : pediatric autoimmune neuropsychiatric disorders associated with streptococcal infections PSGN: : poststreptococcal glomerulonephritis STSS: : streptococcal toxic shock syndrome 1. Clinical prediction rules for group A Streptococcus pharyngitis are unreliable in children, and unless viral etiology is strongly suspected, throat swab with a rapid antigen detection test should be performed. 2. Avoid “proof of cure” cultures when treating pharyngitis. 3. Clindamycin is important in invasive group A Streptococcus infection for toxin mediation but should not be used alone secondary to possible resistance. After completing this article, readers should be able to: 1. Understand the epidemiology, transmission, and major virulence factors of group A Streptococcus (GAS) infections. 2. Plan the appropriate diagnostic evaluation of suspected GAS infection. 3. Recognize the clinical features of, and major complications associated with, invasive and noninvasive GAS infections. 4. Plan appropriate management for a patient with a GAS infection. In 1933, Rebecca Lancefield changed our understanding of β-hemolytic streptococci by developing a system of serologic classification based on the carbohydrate composition of cell wall antigens. Of these organisms, the most significant in human pathogenicity is group A Streptococcus (GAS), otherwise known as Streptococcus pyogenes . (1) GAS is responsible for an impressively wide variety of clinical manifestations, from noninvasive infections, such as pharyngitis, scarlet fever, erysipelas, and cellulitis, to invasive disease, including sepsis, streptococcal toxic shock syndrome (STSS), and necrotizing fasciitis (Table 1). It has also been linked to multiple nonsuppurative complications including acute rheumatic fever (ARF), poststreptococcal glomerulonephritis (PSGN), and the controversial pediatric autoimmune neuropsychiatric disorders associated with streptococcal infections (PANDAS). Globally, an estimated 18 million people are suffering from a serious GAS-related illness, with about 1.78 million new cases annually. Hundreds of millions of people develop less serious GAS infection every year, placing a massive burden on healthcare systems. The …

Objectives To estimate birth prevalence of congenital cytomegalovirus (cCMV) in HIV-exposed uninfected children born in the current era of combination antiretroviral therapy and describe cCMV-related neurodevelopmental and hearing outcomes. Study design The Surveillance Monitoring for ART Toxicities cohort study follows HIV-exposed uninfected children at 22 sites in the US and Puerto Rico. Birth cCMV prevalence was estimated in a subset of participants who had blood pellets collected within three weeks of birth and underwent ≥1 of 6 assessments evaluating cognitive and language development including an audiologic examination between 1 and 5 years of age. Detection of CMV DNA by polymerase chain reaction testing of peripheral blood mononuclear cells was used to diagnose cCMV. Proportions of suboptimal assessment scores were compared by cCMV status using Fisher exact test. Results Mothers of 895 eligible HIV-exposed uninfected children delivered between 2007 and 2015. Most (90%) were on combination antiretroviral therapy, 88% had an HIV viral load of ≤400 copies/mL, and 93% had CD4 cell counts of ≥200 cells/μL. Eight infants were diagnosed with cCMV, yielding an estimated prevalence of 0.89% (95% CI, 0.39%-1.75%). After adjusting for a sensitivity of 70%-75% for the testing method, projected prevalence was 1.2%-1.3%. No differences were observed in cognitive, language and hearing assessments by cCMV status. Conclusions Although birth cCMV prevalence in HIV-exposed uninfected children born to women with well-controlled HIV is trending down compared with earlier combination antiretroviral therapy-era estimates, it is above the 0.4% reported for the general US population. HIV-exposed uninfected children remain at increased risk for cCMV.

Background: Congenital cytomegalovirus (cCMV) is the leading cause of nongenetic congenital hearing loss in much of the world and a leading cause of neurodevelopmental disabilities. Infected babies can be born to women who are seropositive and seronegative prior to pregnancy, and the incidence is approximately 0.6%-0.7% in the United States. Symptoms vary from mild to severe, and hearing loss can be delayed in onset and progressive. Methods: We reviewed the literature to summarize the epidemiology, clinical manifestations, diagnosis, treatment, and future directions of cCMV. Results: The best way to diagnose the infection is with polymerase chain reaction of urine or saliva within 3 weeks after birth, followed by a repeat confirmatory test if positive. Moderately to severely symptomatic neonates should be treated for 6 months with valganciclovir, and some practitioners also choose to treat infants who have isolated hearing loss only. Treatment is not recommended for asymptomatic infants. All infected infants should be screened for hearing loss and neurodevelopmental sequelae. Universal and targeted screening may be cost effective. Currently, no vaccine is commercially available, although multiple candidates are under study. Conclusion: Congenitally acquired cytomegalovirus is found in all communities around the world with a disease burden that is greater than many other well-known diseases. Advances are being made in prevention and treatment; however, improved awareness of the disease among clinicians and patients is needed.

Background The prevalence of congenital cytomegalovirus infection (cCMV) at birth is 0.5%–1% in the United States. Most cCMV newborns are asymptomatic at birth with 10%–15% subsequently developing sequelae, such as hearing loss. Higher cCMV prevalence (2.5%–11.4%) is reported in infants born to HIV-infected women, associated with maternal immune suppression and lack of antiretroviral therapy (ART), with few studies addressing neurodevelopmental (ND) outcomes in their offspring. We report birth prevalence of cCMV in a cohort of HIV-exposed, uninfected infants (HEU) born to women on combination ART with well-controlled HIV and describe ND outcomes through age 5 years. Methods The Surveillance Monitoring for ART Toxicities (SMARTT) study is an ongoing NICHD-funded observational multi-centered cohort study (United States and Puerto Rico) of growth and development of HEU children that commenced in 2007. As of August 1, 2017, participants with stored blood pellets collected ≤3 weeks after birth and at least 1 ND assessment ≥1 year of age had pellets tested by DNA PCR to establish cCMV. Comparisons of ND outcomes (defined in figure) at ages 1, 2, and 5 by cCMV status were made using Wilcoxon and Fisher’s Exact tests. Results Of 895 children meeting study criteria (55% black; 32% white; 40% Latino), 8 had cCMV, yielding a birth prevalence of 0.89% (95% CI 0.39–1.75%). All were asymptomatic and similar to CMV-uninfected infants in gestational age and anthropometric measurements at birth. The last HIV viral load prior to delivery was undetectable in 88% of women. The last available CD4% was Conclusion Birth prevalence of cCMV in HEU children born within the last decade approaches national US prevalence. Preschool HEU children with asymptomatic cCMV at birth did not show poorer language, hearing, and developmental outcomes compared with CMV-uninfected HEU children. Disclosures All authors: No reported disclosures.