Asymptomatic Transmission During the Coronavirus Disease 2019 Pandemic and Implications for Public Health Strategies.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spread rapidly in a few months despite global public health strategies to curb transmission by testing symptomatic patients and social distancing. This review summarizes evidence that highlights transmission by asymptomatic and presymptomatic individuals. Viral load of asymptomatic and symptomatic cases is comparable. Viral shedding is highest before symptom onset, suggesting high transmissibility before symptoms. Within universally tested subgroups, high percentages of SARS-CoV-2 infected asymptomatic individuals were found. Asymptomatic transmission was reported in several clusters, including a Wuhan study showing an alarming rate of intrahospital transmission. Several countries reported higher prevalence among healthcare workers than general population raising concern that healthcare workers could act as silent vectors. Therefore, current strategies that rely solely on "symptom onset" for infection identification need urgent reassessment. Extensive universal testing irrespective of symptoms may be considered, with priority placed on groups with high frequency exposure to positive patients.

Neuroinfectious Diseases in Children: Pathophysiology, Outcomes, and Global Challenges.

Pathogens with affinity for the central nervous system (CNS) in children are diverse in their mechanisms of infecting and attacking the brain. Infections can reach the CNS via hematogenous routes, transneurally thereby avoiding the blood-brain barrier, and across mucosal or skin surfaces. Once transmission occurs, pathogens can wreak havoc both by direct action on host cells and via an intricate interplay between the protective and pathologic actions of the host's immune system. Pathogen prevalence varies depending on region, and susceptibility differs based on epidemiologic factors such as age, immune status, and genetics. In addition, some infectious diseases are monophasic, whereas others may lie dormant for years, thereby causing a dynamic effect on outcomes. Outcomes in survivors are highly variable for each particular pathogen and depend on the vaccination and immune status of the patient as well as the speed by which the patient receives evidence-based treatments. Given pathogens cause communicable diseases that can cause morbidity and mortality on a population level when spread, the burden is often the greatest and the outcomes the worst in low-resource settings. Here we will focus on the most common infections with a propensity to affect a child's brain, the pathologic mechanisms by which they do so, and what is known about the developmental outcomes in children who are affected by these infections.

HIV and Substance Use in Latin America: A Scoping Review.

This scoping review aims to explore the interplay between substance use (SU) and HIV in Latin America (LA). Database searches yielded 3481 references; 196 were included. HIV prevalence among people who used substances (PWUS) ranged from 2.8-15.2%. SU definitions were variable throughout studies, and thus data were not easily comparable. In 2019, only 2% of new HIV infections were attributed to injection drug use (IDU) in LA. Factors associated with HIV among PWUS included being female, IDU and homelessness, and PWUS were likely to engage in risky sexual behaviors, start antiretroviral treatment late, have poor adherence, have treatment failure, be lost to follow-up, have comorbidities, and experience higher mortality rates and lower quality of life, as has been reported in PLWH with SU in other regions. Five intervention studies were identified, and only one was effective at reducing HIV incidence in PWUS. Interventions in other regions have varying success depending on context-specific characteristics, highlighting the need to conduct more research in the LA region. Though progress has been made in establishing SU as a major concern in people living with HIV (PLWH), much more is yet to be done to reduce the burden of HIV and SU in LA.

Neurocysticercosis control for primary epilepsy prevention: a systematic review.

Neurocysticercosis (NCC) is a leading cause of preventable epilepsy in lower- and upper- middle-income countries (LMICs/UMICs). NCC is a human-to-human transmitted disease caused by ingestion of Taenia solium eggs from a Taenia carrier. T. solium infection control is the key to reduce NCC incidence. This systematic review aims to identify T. solium control programs that can provide frameworks for endemic areas to prevent NCC-related epilepsy. A systematic search was conducted in PubMed/Medline, Embase, Web of Science, and Cochrane Library databases in March 2021. After title and abstract review, full texts were screened for qualitative analysis. Additional articles were identified via citation search. Of 1322 total results, 34 unique studies were included. Six major intervention types were identified: national policy (8.8%), community sanitation improvement (8.8%), health education (8.8%), mass drug administration (29.4%), pig vaccination and treatment (32.4%), and combined human and pig treatment (11.8%). Overall, 28 (82.4%) studies reported decreased cysticercosis prevalence following the intervention. Only health education and combined human and pig treatment were effective in all selected studies. NCC causes preventable epilepsy in LMICs/UMICs and its incidence can be reduced through T. solium control. Most interventions that disrupt the T. solium transmission cycle are effective. Long-term sustained results require comprehensive programs, ongoing surveillance, and collaborative effort among multisectoral agencies.

Expanded Newborn Screening and Genomic Sequencing in Latin America and the Resulting Social Justice and Ethical Considerations.

Newborn screening (NBS) has widely been utilized in developed countries as a cost-effective public health strategy that reduces morbidity and mortality. Developing countries, however, are new to the NBS scene and have their own unique challenges, both in instituting the program as well as effectively acting on the results. NBS offers numerous ethical issues on a global scale, however, here we argue that there are unique ethical issues surrounding the development and expansion of newborn screening in Latin America given its highly heterogenous population. Once a NBS program is effectively instated, ethical considerations continue when pursuing expansion of screening to include further conditions. While Latin America grapples with the ethics of expanded newborn screening (ENBS), some developed countries discuss utility of genomic sequencing technologies in the newborn population. When the ability to detect further pathology is expanded, one must know what to do with this information. As rare diseases are identified either on ENBS or via genome sequencing, access to treatments for these rare diseases can be a real challenge. If we consider newborn screening as a global initiative, then we need more than a deontology approach to analyze these challenges; we need an approach that considers the unique characteristics of each territory and tremendous heterogeneity that exists prior to the implementation of these programs. As genomic technology advances further in the developed world, while some developing countries still lack even basic newborn screening, there is a further widening of the gap in global health disparities. The question is posed as to who has responsibility for these newborns' lives on an international level. Without an approach towards newborn screening that accounts for the diverse global population, we believe optimal outcomes for newborns and families across the world will not be achieved.

Development and Evaluation of a Pediatric Epilepsy Training Program for First Level Providers in Zambia.

Introduction. The developing world continues to face challenges in closing the large treatment gap for epilepsy, due to a high burden of disease and few experienced providers to manage the condition. Children with epilepsy are susceptible to higher rates of developmental impairments and refractory disease due to delays or absence of appropriate management as a result. We demonstrated that a structured education intervention on pediatric epilepsy can improve knowledge, confidence, and impact clinical practice of first level providers in Zambia. Methods. Three first-level facilities across Zambia were included. After initial pilot versions and revisions, the final course was implemented at each site. Pre- and post-intervention knowledge and confidence assessments were performed. Additionally, chart reviews were conducted prior to intervention and 4 months after completion of training at each site to assess change on management. Results. Twenty-three of the original 24 participants from all 3 sites completed the training; 48% clinical officers, 43% nurses, 9% other expertise. Of the 15 concepts tested by knowledge assessment, 12 showed trends in improvement, 7 of which were significant (P < .05). Chart reviews demonstrated significant improvement in documentation of seizure description (P = .008), seizure frequency (P = .00), and possible causes of seizures/epilepsy (P = .034). Discussion. Key elements of success to this program included hands on clinical skills building and case-based teaching, development of a program with direct and ongoing input from the target audience, and inclusion of assessments to monitor impact on clinical practice. Future studies looking at health outcomes are necessary to determine sustained impact.

MRI in assessing children with learning disability, focal findings, and reduced automaticity.

OBJECTIVES: In children with clinically diagnosed learning disabilities with focal findings on neurologic or neuropsychological evaluations, there is a hypothesized association between disorders in automaticity and focal structural abnormalities observed in brain MRIs. METHODS: We undertook a retrospective analysis of cases referred to a tertiary-hospital-based learning disabilities program. Individuals were coded as having a focal deficit if either neurologic or neuropsychological evaluation demonstrated focal dysfunction. Those with abnormal MRI findings were categorized based on findings. Children with abnormalities from each of these categories were compared in terms of deficits in automaticity, as measured by the tasks of Rapid Automatized Naming, Rapid Alternating Stimulus Naming, or the timed motor performance battery from the Physical and Neurological Examination for Soft Signs. Data were compared in children with and without disorders of automaticity regarding type of brain structure abnormality. RESULTS: Of the 1,587 children evaluated, 127 had a focal deficit. Eighty-seven had a brain MRI (52 on 1.5-tesla machines and 35 on 3.0-tesla machines). Forty of these images were found to be abnormal. These children were compared with a clinic sample of 150 patients with learning disabilities and no focal findings on examination, who also had undergone MRI. Only 5 of the latter group had abnormalities on MRI. Reduced verbal automaticity was associated with cerebellar abnormalities, whereas reduced automaticity on motor or motor and verbal tasks was associated with white matter abnormalities. CONCLUSION: Reduced automaticity of retrieval and slow timed motor performance appear to be highly associated with MRI findings.