Global flu declines, but some hot spots remain

News brief

After a rise in flu activity in late January, led mainly by the 2009 H1N1 strain and influenza B, levels are declining again, the World Health Organization (WHO) said in its latest update, which covers roughly the last 2 weeks of March.

Of 40 countries reporting in Europe, half continued to report widespread activity, mainly due to influenza B. In East Asia, China's flu activity appears to have peaked, with most detections involving H1N1. Hong Kong and South Korea reported rising activity levels. In Southeast Asia, activity was elevated in Malaysia and Singapore.

In tropical regions of South America, Brazil and Peru reported increasing flu trends. In temperate parts of the Southern Hemisphere, Chile and Australia reported slight activity rises.

Of viruses tested at national flu labs over the reporting period, 75% were influenza A, and, of subtyped influenza A viruses, 70% were H1N1. The earlier months of the Northern Hemisphere's flu season were dominated by H3N2. Of characterized influenza B viruses, all belonged to the Victoria lineage.

Study: Severely ill COVID patients at 16 times higher risk for abnormally rapid heartbeat

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EKG readout
mgstanton / Flickr cc

COVID-19 patients requiring mechanical ventilation are 16 times more likely than non-severely ill peers to experience ventricular tachycardia, an abnormal heart rhythm, within 6 months, according to a study presented at this week's annual meeting of the European Heart Rhythm Association (EHRA) in Barcelona, Spain.

Ventricular tachycardia is a potentially fatal arrhythmia that occurs when the heart's ventricle beats too fast to pump enough oxygenated blood to the rest of the body.

Karolinska Institute researchers in Sweden assessed the long-term risk of abnormal heart rhythms among 3,023 patients with severe COVID-19 released from an intensive care unit (ICU) and 28,463 non-severely ill controls from March 2020 to June 2021. The average participant age was 62 years, 70% were men, and the average follow-up was 9 months.

Higher rates of other heart arrhythmias

Among COVID-19 patients requiring mechanical ventilation, the rates of ventricular tachycardia, atrial fibrillation, other abnormally rapid heart rhythms, and bradycardia/pacemaker implantation were 15.4, 78.4, 99.3, and 8.5 per 1,000 person-years, respectively, compared with 0.9, 6.0, 6.7 and 0.9, respectively, among controls.

Atrial fibrillation is a rapid, irregular heart rate that can lead to shortness of breath and increase the risk of stroke, while bradycardia is an abnormally slow heart rate.

Relative to controls, severely ill COVID-19 patients were at a 16-fold higher risk of ventricular tachycardia, a 13-fold higher risk of atrial fibrillation, a 14-fold higher risk of other abnormally fast heart rhythms, and a 9-fold higher risk of bradycardia/pacemaker implantation.

Study author Marcus Stahlberg, MD, PhD, said COVID-19 patients who require mechanical ventilation often have other underlying medical conditions. "These patients should seek medical attention if they develop palpitations or irregular heartbeats after hospital discharge so they can be evaluated for possible arrhythmias," he said.

Stahlberg said that abnormal heart rhythms after severe COVID-19 infection have been previously reported in most infected ICU patients. "Hospital systems should prepare for an increase in patients requiring management for new onset arrhythmias," he said.

'Protect others' may be more effective message for COVID vaccine uptake

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COVID vaccine sign in New York CityPublic health messages that focus on protecting others are more effective at increasing COVID-19 vaccination rates than messages focused on protecting oneself, according to research published yesterday in PNAS Nexus.

US researchers surveyed more than 3,000 Americans on a visual vaccination campaign. Each of three images described promoting COVID-19 vaccination as a way of protecting oneself, one's circle of friends and family, or one's community. A fourth image simply read "get the vaccine."

Study authors randomly assigned one of the visual images to 3,900 participants in 2021, shortly after the first COVID-19 vaccines were approved for use in the United States. Eight weeks later, 2,268 participants were asked if they had gotten vaccinated.

Messages focusing on protecting others (the average of "protect your circle" and "protect your community") led to higher odds of COVID-19 vaccination than messages that urged viewers to "protect yourself." However, overall vaccination rates for participants who saw the narrative messages did not differ from a control group. 

We find that visual narrative risk communication is an effective approach to encourage risk mitigation behavior.

In general, the narrative of doing something for others, with the implied moral motivation, was more effective than nonnarrative, take-action-only messaging, the authors said.

"Responding to the call from the public health community, we find that visual narrative risk communication is an effective approach to encourage risk mitigation behavior," the authors concluded.

FDA advisers recommend approval of combination antibiotic for bacterial pneumonia

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The US Food and Drug Administration's (FDA's) Antimicrobial Drug Advisory Committee (AMDAC) voted unanimously this week to support approval of the investigational antibiotic candidate sulbactam-durlobactam for the treatment of patients with hospital-related bacterial pneumonia caused by Acinetobacter.

The drug, developed by Entasis Therapeutics, combines a beta-lactam antibiotic (sulbactam) with a novel, broad-spectrum beta-lactamase inhibitor and specifically targets Acinetobacter baumannii-calcoaceticus complex, a multidrug-resistant pathogen that causes severe and life-threatening infections. The World Health Organization has labeled carbapenem-resistant Acinetobacter a critical pathogen.

Phase 3 trial results released in 2021 showed that sulbactam-durlobactam was statistically non-inferior to colistin in patients with hospital-acquired and ventilator-associated pneumonia caused by carbapenem-resistant A baumannii and exhibited a favorable safety profile.

The Committee's unanimous recommendation ... moves us closer to potentially addressing the urgent need for new treatment options.

AMDAC voted to recommend approval by a vote of 12-0, based on a favorable benefit-risk assessment. The recommendation is not binding, but the FDA generally follows recommendations from its advisory committees.

"The Committee's unanimous recommendation in favor of sulbactam-durlobactam, the first pathogen-targeted therapy for Acinetobacter, moves us closer to potentially addressing the urgent need for new treatment options for patients with serious and life-threatening infections caused by this pathogen," David Altarac, MD, chief medical officer of Entasis Therapeutics, said in a press release from Innoviva (Entasis is a wholly owned subsidiary of Innoviva). "We appreciate the Committee's thoughtful deliberation and strong vote of confidence, and look forward to working with the FDA as it completes its review."

The target action date for the FDA's decision is May 29.

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