ABSTRACT
BackgroundUrea Breath Tests (UBTs) are common non-invasive tests performed in hospitals under the guidance of trained technicians. However, COVID-19 has reduced access to within-hospital UBTs. Self-conducted UBT (SUBT) at home has been suggested as an alternative. This study aims to compare the efficacy of SUBT with written compared to video instructions.MethodsThe study was divided into 3 parts. In Part 1, consecutive first-time UBT patients were randomized to receive either written or video instructions. In Part 2, the original video was enhanced. For Parts 1 and 2, a competency score of 1-5 based on the assessment of the 5 key steps was determined by a trained observer. Having reviewed the steps for breath collection in the first 2 parts, we went on to Part 3 to determine if breath collection with these steps would be successful. A further enhanced instructional video was created and successful collection of breath was recorded based on detection of sufficient recovered C-13 in the breath bag for the baseline test.ResultsIn total, 129 patients were recruited for the study. Patients excluded for this study included those who had visual or hearing impairment, cognitive impairment and those who did not understand English as our instructional materials were in English. For Part 1, 20 patients were randomised into written (n=10) and original video (n=10) groups. There was numerical improvement but no statistically significant difference in median scores for written and video instructions (2 vs 4, p=0.055). A further 10 patients were recruited for Part 2, the enhanced video group. Median scores were statistically improved for enhanced video compared to written (5 vs 2, p=0.043). In Part 3, 99 patients were recruited. Barring machine fault, all the UBTs were successful without repeating the breath test.ConclusionsAn enhanced instructional video is highly successful at enabling SUBT. This can improve the safety of patients and operators by allowing UBTs to be conducted at home, while maintaining accuracy. This would reduce the time that patients spend in the hospital and reduce exposure to potential COVID infections.
ABSTRACT
OBJECTIVE: Synthesise evidence on production of SARS-CoV-2 antibodies in human milk of individuals who had COVID-19, and antibodies' ability to neutralise SARS-CoV-2 infectivity. DESIGN: A systematic review of studies published from 1 December 2019 to 16 February 2021 without study design restrictions. SETTING: Data were sourced from PubMed, MEDLINE, Embase, CNKI, CINAHL and WHO COVID-19 database. Search was also performed through reviewing references of selected articles, Google Scholar and preprint servers. Studies that tested human milk for antibodies to SARS-CoV-2 were included. PATIENTS: Individuals with COVID-19 infection and human milk tested for anti-SARS-CoV-2 neutralising antibodies. MAIN OUTCOME MEASURES: The presence of neutralising antibodies in milk samples provided by individuals with COVID-19 infection. RESULTS: Individual participant data from 161 persons (14 studies) were extracted and re-pooled. Milk from 133 (82.6%) individuals demonstrated the presence of anti-SARS-CoV-2 immunoglobulin A (IgA), IgM and/or IgG. Illness severity data were available in 146 individuals; 5 (3.4%) had severe disease, 128 (87.7%) had mild disease, while 13 (8.9%) were asymptomatic. Presence of neutralising antibodies in milk from 20 (41.7%) of 48 individuals neutralised SARS-CoV-2 infectivity in vitro. Neutralising capacity of antibodies was lost after Holder pasteurisation but preserved after high-pressure pasteurisation. CONCLUSION: Human milk of lactating individuals after COVID-19 infection contains anti-SARS-CoV-2-specific IgG, IgM and/or IgA, even after mild or asymptomatic infection. Current evidence demonstrates that these antibodies can neutralise SARS-CoV-2 virus in vitro. Holder pasteurisation deactivates SARS-CoV-2-specific IgA, while high-pressure pasteurisation preserves the SARS-CoV-2-specific IgA function.