Again, no COVID-19 benefit found from hydroxychloroquine, azithromycin
A retrospective study of COVID-19 patients in New York City hospitals found that treatment with the antimalaria drug hydroxychloroquine, the antibiotic azithromycin, or both was not significantly associated with differences in in-hospital mortality compared with patients who received neither drug. But cardiac arrest was more frequent in patients treated with both drugs, according to the findings published yesterday in JAMA.
Of 1,438 COVID-19 patients treated at 25 New York City hospitals from Mar 15 through Mar 28, 735 (51.1%) received hydroxychloroquine and azithromycin, 271 (18.8%) received hydroxychloroquine alone, 211 (14.7%) received azithromycin alone, and 221 (15.4%) received neither drug. Patients treated with hydroxychloroquine and azithromycin and hydroxychloroquine alone were more likely to be obese and have diabetes than those who received azithromycin alone or neither drug, and patients treated with hydroxychloroquine alone had the highest levels of chronic lung disease and cardiovascular conditions. Patients treated with both drugs together were also sicker.
Analysis of patient outcomes found that overall in-hospital mortality was 20.3% (95% confidence interval [CI], 18.2% to 22.4%). Following adjustments for demographics, preexisting conditions, and illness severity, the researchers found no significant differences in mortality between receiving hydroxychloroquine and azithromycin (adjusted hazard ratio [HR], 1.35; 95% CI, 0.76 to 2.40), hydroxychloroquine alone (adjusted HR, 1.08; 95% CI, 0.63 to 1.85) or azithromycin alone (adjusted HR, 0.56; 95% CI, 0.26 to 1.21) compared with neither drug.
Adjusted analysis of secondary outcomes found that, compared with those who received neither drug, cardiac arrest was significantly more likely in patients treated with hydroxychloroquine and azithromycin (adjusted odds ratio [OR], 2.13; 95% CI, 1.12 to 4.05), but not hydroxychloroquine alone (adjusted OR, 1.91; 95% CI, 0.96 to 3.81) or azithromycin alone (adjusted OR, 0.64; 95% CI, 0.27 to 1.56).
"The lack of observed benefit of hydroxychloroquine associated with in-hospital mortality, following adjustment for preexisting disease and severity of illness on admission, is consistent with recently reported data from other observational studies," the authors wrote.
They added, though, that the interpretation of the findings may be limited by the observational design of the study. "Clinical trials remain needed to provide definitive causal evidence of the effect of hydroxychloroquine and azithromycin on mortality, while also providing an opportunity to more finely control baseline patient severity and the dose and timing of drug administration," they said.
May 11 JAMA study
Close contact may have aided German COVID-19 super-spreading event
Analysis of a scientific advisory board meeting in Germany in which a presymptomatic COVID-19 patient infected at least 11 of 13 other participants suggests hand-shaking and face-to-face contact may have been possible modes of coronavirus transmission, European researchers reported yesterday in Emerging Infectious Diseases.
The meeting, which took place Feb 20-21 in Munich, involved 14 clinicians and scientists gathered in a single hotel conference room, none of whom showed any signs of infection before or during the meeting. The index patient, who also shared a 45-minute taxi ride with three other meeting participants, reported no symptoms during the meeting but sought care for fever after returning home the evening of Feb 21 and tested positive for SARS-CoV-2, the virus that causes COVID-19. National authorities contacted and tested meeting participants on Feb 26 and 27, and 11 additional participants tested positive. Isolation of the infected participants at home or in the hospital resulted in an additional 14 infections.
Five of the meeting participants had mild or no symptoms, and 6 (including the index patient) had moderate illness. The index patient believes he was infected by an outpatient he examined in Milan, Italy, on Feb 18.
While the exact mode of transmission is not yet known, the researchers identified four plausible routes: droplets from face-to-face contact, aerosolized droplets via air flow, fomites (contaminated objects), and hand shaking. They found that there was face-to-face contact lasting more than 5 minutes between the index patient and the 11 infected participants over the course of two lunches and two coffee breaks (also held in the same room) and one social dinner.
In addition, the meeting room was small and heated by conventional radiators, which could have aided aerosol transmission. Transmission via fomites was considered the least likely, because few objects (bottles, coffee pots, forks) were shared by participants.
May 11 Emerg Infect Dis study
Study: CDC non-test isolation recommendation may fall short
The US Center for Disease Control and Prevention (CDC) non-test strategy for releasing COVID-19 patients from isolation may send patients back into the community too early, resulting in more community spread, researchers from the Mayo Clinic wrote yesterday in a letter to the Journal of Infection.
They note that the CDC has two strategies for determining when a COVID-19 patient can leave isolation, a non–test-based one that relies on symptom improvement and days since symptoms began, and a testing one based on symptom improvement and two negative tests conducted more than 24 hours apart.
To assess the strategies, they reported on their experiences with COVID-19 patients who received care and follow-up through Mayo's COVID Virtual Clinic in Jacksonville, Florida. They described their testing findings in 72 patients who met the CDC's non-testing isolation release criteria, finding that 22 (30.1%) were negative on the first two tests and 69.9% positive. Of those who failed testing, 36 (72%) were positive on the first test, and 14 (28%) were negative on the first test but positive on the second. The team also found that the average time it took from symptom onset to negative testing was 19 days.
Since the non-test system might release people from isolation too early, it could be helpful to lengthen self-isolation to more than 14 days after symptom onset, they wrote.
May 11 J Infect letter