Association between severe acute respiratory syndrome coronavirus 2 antibody status and reinfection: A case-control study nested in a Colorado-based prospective cohort study

The association between the presence of detectable antibodies to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and SARS-CoV-2 reinfection is not well established. The objective of this study was to determine the association between antibody seronegativity and reinfection.

METHODS

Participants in Colorado, USA, were recruited between June 15, 2020, and March 28, 2021, and encouraged to complete SARS-CoV-2 molecular ribonucleic acid (RNA) and serology testing for antibodies every 28 days for 10 months. Participants with reinfections (positive SARS-CoV-2 RNA test ≥ 90 days after the first positive RNA test) were matched to controls without reinfections by age, sex, date of the first positive RNA test, date of the last serology test, and serology test type. Using conditional logistic regression, case patients were compared to control patients on the last serologic test result, with adjustment for demographic and clinical confounders.

RESULTS

The cohort (n = 4,235) included 2,033 participants with ≥ 1 positive RNA test, of whom 120 had reinfection. Among the 80 case patients who could be matched, the last serologic test was negative in 12 of the cases (15.0 %) whereas the last serologic test was negative in 77 of 1,034 (7.5 %) controls. Seronegativity (adjusted OR [aOR] 2.24; 95 % CI 1.07, 4.68), Hispanic ethnicity (aOR 1.87; 95 % 1.10, 3.18), and larger household size (aOR 1.15; 95 % 1.01, 1.30 for each additional household member) were associated with reinfection.

CONCLUSIONS

Seronegative status, Hispanic ethnicity, and increasing household size were associated with reinfection. Serologic testing could be considered to reduce vaccine hesitancy in higher risk populations.

The evaluation and management of acute poisoning emergencies

Emergency physicians will regularly be called upon to care for poisoned patients. The purpose of this article is to review the general approach to the poisoned patient. Specific signs and symptoms will be identified that may clue the clinician into a specific toxin class as a diagnosis. Necessary testing in poisonings will be highlighted. This article will also introduce the basics of gastrointestinal decontamination and antidotes against select poisons.

Managing the child infected with HIV

Care of the HIV-infected/exposed infant and child is both routine and challenging. Routine well child care and immunizations are an important part of maintaining and monitoring health status. Challenges arise in the management of acute illnesses and the numerous crises that are experienced by the family caring for that child. Therapy guidelines now provide a logical way in which to initiate antiretroviral treatment and PCP prophylaxis. In HIV-infected children with early disease, common pathogens initially predominate, and only in advanced immune suppression does care become complicated enough to require expert consultation. With increasing numbers of HIV-infected women, perinatally acquired infections in infants will become more common. Early testing and identification will increasingly be important as a way to impact on the significant morbidity and mortality seen in infants less than 6 months old. A caring, compassionate, and comprehensive approach to the care of HIV-infected infants and children results in increased survival and lengthening of disease-free time. Providing this vitally needed care is both satisfying and stimulating.

Applying cooperative learning in health education practice

Cooperative learning encompasses both a teaching philosophy and instructional methods that encourage students to work together to maximize learning. This article examines the rationale for incorporating cooperative learning in health education, reviews cooperative learning basics, and provides an example of cooperative learning technique in health education.

Interactions between HIV-1 and cytomegalovirus in human osteosarcoma cells carrying both viruses

Cytomegalovirus (CMV) and the human immunodeficiency virus type 1 (HIV-1) may interact in the pathogenesis of AIDS. We compared CMV replication in human osteosarcoma (HOS) cells to that in HOS cells genetically engineered to contain an envelope-deficient HIV-1 proviral construct (designated HOS-HXG). Following acute CMV infection of each cell line, HOS-HXG cells contained higher numbers of intranuclear CMV nucleocapsids than did HOS cells. Infectious CMV could be persistently detected in culture supernatant fluids of the CMV-infected HOS-HXG cells, whereas CMV was lost over several weeks from HOS cells infected with CMV in parallel. HIV-1 CMV pseudotypes were not detected in supernatant fluids from CMV-infected HOS-HXG cells. On day 119 after CMV infection, these cultures were superinfected with HIV-1. These dually infected HOS-HXG cells produced infectious HIV-1 and exhibited markedly enhanced CMV replication compared to parental CMV-infected HOS-HXG cells. Two different HIV-1 tat gene function antagonists, Ro24-7429 and chemically modified antibodies to the Tat protein, did not inhibit the replication of CMV in either acute or persistent infections of HOS-HXG cells at concentrations that inhibited HIV-1 replication.