Study: Universal COVID screening among hospitalized patients has unintended consequences

News brief

covid test — *Cory Doctorow / Flickr cc*

A cohort study on systematic SARS-CoV-2 screening for asymptomatic hospitalized patients during the COVID-19 pandemic shows that 36.5% of all positive results were false-positives, which led to unintended consequences.

The study, recently published in JAMA Network Open, was based on 42,666 asymptomatic patients seen at the University Hospital Basel in Basel, Switzerland, from February 2021 through December 2022.

Among the 44,666 patients, 761 patients (1.2% of tests) had positive results for COVID-19. Of these, 483 patients (63.5%) had true-positive results. Among those with false-positives, the authors found several unintended and potentially harmful consequences of the screening tests.

Half of patients with a false positive experienced unnecessary isolation, 16.5% were exposed to patients with true-positive SARS-CoV-2 test results by cohorting, and 3.2% received delayed interventions.

Screening results correlated to wastewater

While false-positives were common, results from universal screenings correlated with community incidence and wastewater viral load.

Overall, the authors said universal screening may support infection control during times of high community activity but has limited benefit during low-incidence periods when false-positives increase.

Our findings highlight the considerable unintended outcomes associated with false-positive results, which can strain health care systems and adversely affect patient outcomes.

“Our findings highlight the considerable unintended outcomes associated with false-positive results, which can strain health care systems and adversely affect patient outcomes, the authors concluded. “These results emphasize the importance of context-driven implementation, in which screening efforts are aligned with epidemiological trends and resource availability.”

Hepatitis B and C claimed 1.3 million lives in 2024, WHO reports

News brief

Stephanie Soucheray, MA

The World Health Organization (WHO) released a new report on hepatitis today, marking the World Hepatitis Summit. Since 2015, the annual number of new hepatitis B infections has dropped by 32%, and hepatitis C-related deaths have fallen by 12% around the world.

But despite progress, the virus still causes significant morbidity and mortality, with more than 4,900 new infections caused by hepatitis B and C every day, or 1.8 million each year. In 2024, WHO estimates 287 million people were living with chronic hepatitis B or C infection. Notably, of the 240 million people living with chronic hepatitis B in 2024, fewer than 5% were receiving treatment.

Around the world, countries are showing that eliminating hepatitis is not a pipedream.

“Around the world, countries are showing that eliminating hepatitis is not a pipedream, it's possible with sustained political commitment, backed by reliable domestic financing,” said Tedros Adhanom Ghebreyesus, PhD, WHO director-general, in a statement. “At the same time, this report shows that progress is too slow and uneven. Many people remain undiagnosed and untreated due to stigma, weak health systems and inequitable access to care.”

10 countries see 70% of hepatitis B-related deaths

An estimated 1.1 million people died from hepatitis B and 240,000 from hepatitis C in 2024, as the viruses cause liver cirrhosis and hepatocellular carcinoma. Just 10 countries, Bangladesh, China, Ethiopia, Ghana, India, Indonesia, Nigeria, the Philippines, South Africa and Vietnam, accounted for 69% of the hepatitis B-related deaths.

A birth dose of hepatitis B vaccine prevents 95% of acute and chronic infections. Birth-dose vaccination is lacking in the WHO African Region , where 68% of new hepatitis B infections are diagnosed annually, but only 17% of newborns are vaccinated.

Overall, hepatitis B prevalence among children under age 5 has also decreased to 0.6%, with 85 countries achieving or surpassing the 2030 target of 0.1%, the WHO said.

Quick takes: Measles, meningitis outbreaks in Chad; clade 1b mpox in Denmark; gonorrhea vax candidate

News brief

Chris Dall, MA

Dual outbreaks of measles and meningitis C are occurring in eastern Chad as thousands flee conflict in neighboring Sudan and crowd into refugee camps, according to Medecins Sans Frontieres (MSF). In the town of Adre, which lies on the border between the two countries, meningitis cases jumped from 18 in January to 212 from March into April, and 25 children have died. Measles cases rose from 16 to 371 in the same period. In response, MSF and Chad’s Ministry of Health have launched emergency vaccination campaigns against measles and meningitis, and MSF has tripled its isolation capacity for measles.
After reporting its first cases of mpox infection caused by the clade 1b variant last week, Denmark has detected three additional cases, the Statens Serum Institutet (SSI) reports. While three of the cases are in people who recently traveled outside the country, one of the cases appears to have been locally transmitted. All four patients have had mild illness, and Danish health authorities say the overall risk to the population is low. Denmark is one of several European countries that have reported locally transmitted infections with clade 1B, which originated in Central and East Africa in 2023. “Experience from other European countries shows that the infection can spread locally once the variant is introduced," Uffe Vest Schneider, PhD, head of SSI’s department of virology and microbiological preparedness, said in a news release.
CARB-X (Combating Antibiotic-Resistant Bacteria Biopharmaceutical Accelerator) announced today that it’s awarding $2.6 million to vaccine-platform company AdJane to advance development of a vaccine candidate for gonorrhea. The company’s platform is based on native outer membrane vesicles derived from Neisseria meningitidis, which can be applied across viral and bacterial pathogens. “AdJane’s approach represents a technically grounded strategy that aims to address key challenges in generating protective immunity to reduce the infection rate of gonorrhea and slow the spread of antimicrobial resistance,” CARB-X interim research & development chief Richard Alm, PhD, said in a press release.