Recent dengue infection may increase odds of COVID infection, hospital care

News brief

Dengue virus — *Sanofi Pasteur / Flickr cc*

In Open Forum Infectious Diseases, researchers link dengue infection to a slightly increased risk of subsequent COVID-19 infection and a significantly higher risk of severe COVID-19 illness and hospitalization.

For the study, investigators at the National Centre for Infectious Diseases in Singapore used data from national registries to evaluate COVID-19 infections and outcomes among almost 3.4 million adults from July 2021 to October 2022, when waves of the SARS-CoV-2 Delta and Omicron variants followed a dengue outbreak.

"Elucidating whether prior dengue potentially confers cross-protection against COVID-19 is of public health importance in tropical countries at-risk of overlapping dengue and COVID-19 epidemics," the authors wrote.

Triple the risk of severe COVID-19

In total, 13,434 dengue infections were documented, and nearly all (96.8%) were mild and didn't require hospitalization.

During the same period, 1,253,520 subsequent COVID-19 cases were recorded, of which 9.2% occurred during the Delta wave and 90.8% amid Omicron. Most cases (82.3%) occurred in people who received a booster vaccine dose before infection. The average time from dengue to COVID-19 infection was 94.7 days.

Elucidating whether prior dengue potentially confers cross-protection against COVID-19 is of public health importance in tropical countries at-risk of overlapping dengue and COVID-19 epidemics.

Dengue infection was tied to a modestly elevated risk of subsequent COVID-19 infection (adjusted hazard ratio [aHR], 1.13) and a more than triple risk of severe COVID-19 (aHR, 3.39) and hospitalization (aHR, 3.25) across vaccination subgroups.

In adults without previous dengue, the unadjusted incidence of COVID-19 was 894.7 cases per million person-days, compared with 1,537.5 per million person-days among those with dengue.

A lower risk of severe COVID-19 reinfection and hospitalization was seen with a longer time since dengue infection, with lower risk of COVID-19 hospitalization among those with dengue 1 or 2 years (adjusted odds ratio [aOR], 0.39) and 3 or more years before (aOR, 0.33), versus less than 1 year before.

"Increased risk of adverse COVID-19 outcomes following dengue infection may potentially be attributable to overlapping sociodemographic factors predisposing at-risk individuals to both dengue infection and severe COVID-19; or may suggest the possibility of increased risk of subsequent severe COVID-19 through an antibody dependent-like enhancement mechanism, after a preceding infection," the researchers wrote.

FDA OKs temporary import of Portuguese syphilis drug for newborns to ease US shortage

News brief

Lisa Schnirring

Mark Cuban's Cost Plus Drug Company announced yesterday that it has received temporary approval from the US Food and Drug Administration (FDA) to import penicillin G benzathine into the United States to ease demand-driven shortages for babies born with syphilis.

The drug is produced by Portugal-based Atral Laboratories under the Lentocilin brand name, according to a June 11 letter from the company to healthcare providers. The adult and pediatric versions of the drug in the United States are made by Pfizer as Bicillin-LA.

Lentocilin is available as a powder and diluent for injection. In its letter, the company noted some differences between its drug and the US version, including labeling and the fact that it contains soy, which may cause allergic reactions in some people. It also said the packaging doesn't contain a warning that the drug could be fatal if given by other routes, but that the prescribing information emphasizes that Lentocilin must be administered only by deep muscular injection.

On X yesterday, Cuban said the shortage of the drug for babies with syphilis was worsened by the high price for the drug, which will be available through Cost Plus as a fraction of the cost, just $15 instead of $500.

Second temporary import approval for syphilis treatment

Lentocilin is the second drug the FDA has approved for temporary import to address US shortages. In January it allowed the temporary import of a similar drug from a French pharmaceutical company that makes penicillin G benzathine, which in the United States is made by Pfizer under the Extenciline brand name.

US syphilis rates are climbing, with notable spikes in 2020 and 2021. Rates of infections in newborns are 10 times higher than the 10-year average, the highest in three decades.

Omadacycline post-marketing study adds evidence for use in treating pneumonia

News brief

Lisa Schnirring

Paratek Pharmaceuticals today announced promising findings in a phase 3 clinical trial that compared its broad-spectrum antibiotic omadacycline to moxifloxacin for treating patients with moderate to severe community-acquired bacterial pneumonia (CABP).

chest xray with hot spots — Chinnapong / iStock

The Food and Drug Administration (FDA) approved the drug, a modified tetracycline antibiotic sold under the Nuzrya brand name, in 2018 for the treatment of CABP and skin infections. Omadacycline is designed to overcome tetracycline resistance and has shown activity against both gram-positive and gram-negative bacteria, including antibiotic-resistant strains.

In the lead-up to FDA approval, clinical trials had shown that the drug was noninferior to moxifloxacin for treating CABP.

Support for updating clinical guidelines

In a press release, Randy Brenner, MS, Partek's chief development and regulatory officer, said the new trial confirms that omadacycline is an effective and well-tolerated option for treating CABP. "With the completion of this post-marketing study, our clinical study database now includes data from 1,438 pneumonia patients and is the largest clinical trial dataset in pneumonia across all antibiotics approved by the FDA in the last decade," he said.

He said the company believes the latest findings support a potential update to American Thoracic Society/Infectious Diseases Society of America guidelines for treating CABP. Paratek said the firm will submit the results for publication.

Two phase 3 studies in 2019 showed the omadacycline was just as effective as standard antibiotics for treating CABP and skin infections, but some experts said the clinical value of the new drug is unclear.