Remdesivir linked with COVID-19 clinical improvement and safety
Remdesivir treatment of hospitalized patients with noncritical COVID-19 is associated with better clinical improvement, shorter recovery and hospital stays, and safety, according to a meta-analysis of five randomized clinical trials published today in the Journal of Antimicrobial Chemotherapy. No significant association was found in regards to mortality.
The studies covered 13,544 adult patients from at least 30 countries, of which 391 received a 5-day regimen and 3,839 received a 10-day regimen. Of the studies, which were published from Jan 1 to Nov 18, 2020, three were open-label, and two were double-blind.
Patients who received a 5-day regimen had greater clinical improvement than those in the control group (odds ratio [OR], 1.68; 95% confidence interval [CI], 1.18 to 2.40), while those who received a 10-day regimen showed no significant improvement compared with the control group.
Both regimens were associated with greater likelihood of hospital discharge, compared with the control (5-day regimen OR, 1.73; 95% CI, 1.28 to 2.35, and 10-day regimen OR, 1.32; 95% CI, 1.09 to 1.60). Recovery was also better in the remdesivir groups than in the control groups, with a 1.80 OR for the 5-day regimen and a 1.29 OR for the 10-day regimen (95% CI, 1.31 to 2.48, and 95% CI, 1.03 to 1.60, respectively).
Remdesivir (Veklury) has been authorized for emergency use by the US Food and Drug Administration since May 1, 2020. The researchers acknowledge that their analysis did not include critical COVID-19 patients or those who needed mechanical ventilation or extracorporeal membrane oxygenation.
Mar 24 J Antimicrob Chemother study
COVID-19 antibodies persist from days to potentially much longer
Antibodies derived from COVID-19 infection can persist for less than 14 days to potentially much longer post-symptom onset, according to a study published yesterday in The Lancet Microbe. Regardless of the duration of detectable antibody levels, though, the researchers found similar levels of T cells in participant blood samples.
The study's 164 Singapore participants fell into the following groups: negative (11.6% who never had antibodies at the 30% inhibition level), rapid waning (26.8% who had varying levels of antibodies 20 days post-symptom onset but reverted in less than 180 days), slow waning (28.0% who were antibody-positive at 180 days), persistent (31.7% who showed little change in antibody levels up to 180 days), and delayed response (1.8% who showed a significant rise in antibodies at 90 or 180 days post-symptom onset).
Despite varying antibody duration, a subset of 23 randomly selected participants showed that, at day 180 post-symptom onset, T cell levels were similar across all groups.
Those with persistent antibodies had higher levels of pro-inflammatory cytokines, pro-inflammatory chemokines, and growth factors after 180 days post-symptom onset. They also tended to be older and have more comorbidities, which the researchers believe could be because of a relationship between disease severity and antibody duration.
Median antibody duration for the rapid waning, slow waning, and persistent groups were 96, 201, and 580 days, respectively, but large variation occurred on the individual level. For instance, in the persistent group, detectable antibody levels were predicted to last between 326 and 14,881 days. Despite this, the researchers note, "The predicted and actual 270 days data [collected in 56 participants] had a Pearson correlation of 0.84, showing robustness and validating our neutralising antibody longevity prediction algorithm."
"The key message from this study is that the longevity of functional neutralising antibodies against SARS-CoV-2 can vary greatly and it is important to monitor this at an individual level," said corresponding author Wang Linfa, PhD, in a Duke-NUS Medical School press release. "This work may have implications for immunity longevity after vaccination, which will be part of our follow-up studies."
Mar 23 Lancet Microbe study
Mar 23 Duke-NUS press release
Healthcare workers have rising COVID-19 vaccine acceptance
In December 2020, more than half (55.3%) of healthcare workers responding to a survey said they would be willing to receive a COVID-19 vaccination, a significant rise from previous study results, which rated acceptance as low as one third, according to a research letter yesterday in JAMA Network Open.
The researchers wanted to see if time, as well as the US Food and Drug Administration's (FDA's) continuing emergency-use authorization (EUA) process, affected vaccine acceptance. To begin measuring this, 16,292 healthcare workers completed a five-question online survey on or shortly after Dec 4, 2020—or on "the eve of vaccine distribution," as the researchers put it.
While 55.3% said they would take the vaccine, 16.3% said no, and 28.4% were undecided. Patient-facing employees, who made up 58.2% of the cohort, were more likely than those without patient contact to have vaccine acceptance (57.3% vs 51.4%). They were also more likely to say no to the vaccine, but the researchers note that the difference is insignificant. (17.3% vs 15.6%).
Nine of 10 people who said no or who were undecided cited concerns about unknown risks of the vaccine. Other reasons included concern about adverse effects (57.4%), desire to hear about others' experiences first (44.3%), and distrust of the FDA's process (21.1%).
As of Feb 18, 2021, 67.2% of the surveyed healthcare workers had received at least one COVID-19 vaccine dose.
"The trend of increased intention to receive a vaccine as the EUA processes unfolded and the greater number of employees who actually received a vaccine compared with respondents who intended to do so suggest that the highly visible nature of the actual processes may have reassured many respondents."
Mar 23 JAMA Netw Open research letter
H5N1 avian flu strikes more poultry in Niger
Animal health officials in Niger reported another highly pathogenic H5N1 avian flu outbreak in poultry, which follows a recent appearance of the virus in the same area, according to a notification from the World Organization for Animal Health (OIE).
The latest outbreak began on Mar 13 at a commercial farm near the country's capital city of Niamey that housed chicks and layers. The virus killed 27,000 of 30,000 susceptible birds, and the survivors were culled to control the spread of the virus.
In other highly pathogenic avian flu developments, European countries reported more outbreaks in wild birds involving various strains, including H5N5 in the Czech Republic, H5 in Sweden, and H5N4 in the Netherlands.
Mar 19 OIE report on H5N1 in Niger
Mar 18 OIE report on H5N5 in the Czech Republic
Mar 18 OIE report on H5 in Sweden
Mar 19 OIE report on H5N4 in the Netherlands