A systematic review and meta-analysis of data from 28 countries shows rising Helicobacter pylori antibiotic resistance in children, an international team of researchers reported last week in BMC Medicine.

The review, led by researchers from Iran's Shahid Beheshti University of Medical Sciences, included 63 studies involving 15,953 children from 28 countries in 5 World Health Organization regions. The European region was the most widely represented area, with 30 studies involving 7,462 children, followed by the Western Pacific region (20 studies, 7,202 children). The average age of study participants was 11.8 years and 59% were female. The studies, published from 2000 to 2023, assessed H pylori resistance rates to clarithromycin, metronidazole, levofloxacin, amoxicillin, and tetracycline. 

H pylori affects over half the global population, with a higher incidence in developing countries. Infection is associated with gastritis, peptic ulcers, and gastric cancer. The global prevalence of H pylori in children, in whom the bacterium can contribute to malnutrition and growth issues, is 32.3%. While treatment involves a combination of antibiotics and antisecretory drugs, such as proton pump inhibitors, rising antibiotic resistance has emerged as a leading reason for treatment failure in some parts of the world. 

Findings warrant 'urgent attention'

The rate of primary resistance to metronidazole was 35.3%, clarithromycin 32.6%, levofloxacin 13.2%, amoxicillin 4.8%, and tetracycline 1.2%. The rates of secondary resistance, based on information from 115 isolates, were 69.3% for clarithromycin, 45.8% for metronidazole, 36.4% for levofloxacin, and 2.9% for tetracycline. Analysis of time trends found significant increases in resistance from 2000-2005 to 2020-2023, escalating from 1.1% to 16.1% for amoxicillin, 20.4% to 49.5% for clarithromycin, 25.0% to 38.5% for metronidazole, and 2.0% to 2.7% for tetracycline.

The escalating trend of H. pylori antibiotic resistance in children warrants urgent attention globally.

The highest rate of metronidazole resistance (61.5%) was found in children ages 5 to 10, while the highest rate of clarithromycin resistance (51%) was in children 0 to 5 years. 

"The escalating trend of H. pylori antibiotic resistance in children warrants urgent attention globally," the study authors wrote. "National and regional surveillance networks are required for antibiotic stewardship in children infected with H. pylori."

The first study measuring antibody response to respiratory syncytial virus (RSV) vaccinations in immunocompromised individuals shows approximately 40% of participants did not seroconvert or achieve a conservative neutralization threshold post-vaccination. 

The study is published in JAMA. 

Previous studies have measured seroconversion in immunocompetent adults, resulting in 13- to 14-fold increases in antibody titers 1 month after vaccination and 82.6% efficacy against confirmed RSV-related lower respiratory tract disease.

Study suggests need for additional vaccine doses 

In the present study, 38 immunocompromised patients from a group of 139 had antibody levels measured at baseline and 4 weeks post-vaccination. Of the 38 patients, 82% were solid organ transplant recipients, and 74% were taking 2 or more immunosuppressive medications. The average age was 66. 

In total, 23 participants (61%) achieved seroconversion at 4 weeks. 

Low antibody titers may indicate a role for additional vaccine doses to enhance immune response among immunocompromised persons.

“Approximately 40% of immunocompromised participants did not seroconvert or achieve a conservative neutralization threshold postvaccination,” the authors wrote. “Low antibody titers may indicate a role for additional vaccine doses to enhance immune response among immunocompromised persons.”

The latest lab findings on samples collected during an investigation into a febrile illness outbreak in a remote district of the Democratic Republic of the Congo (DRC) reveal common respiratory viruses and falciparum malaria, the World Health Organization (WHO) said in a December 27 outbreak update.

A total of 430 samples were collected from patients with suspected infections in the Panzi health zone, and initial rapid tests and fever panel tests were positive for malaria in 62% and 65% of samples, respectively. Of 89 other samples tested at the INRB in Kinshasa, 64 were positive for common respiratory viruses, including 2009 H1N1 seasonal flu, rhinoviruses, SARS-CoV-2, human coronaviruses, parainfluenza virus, and adenovirus. Further lab tests are still under way, including virological and bacterial analysis.

The WHO now refers to the outbreak as acute respiratory infections complicated by malaria. Officials said acute malnutrition led to an increase in severe illnesses and deaths.

Cases rise, but deaths remain stable

During the investigation, outbreak responders cast a wide net to identify potentially related cases, which resulted in a rapid increase in cases that met the case definition. As of December 16, 891 cases were reported, 48 of them fatal. However, deaths have remained relatively stable.

Cases have remained steady, except for the week ending December 15, which the WHO said may be partly due to increased illness transmission during the rainy season but likely reflects increases in surveillance and case finding. “Notably, the increase in cases is not matched with a comparable increase in deaths," the update said.

The WHO assessed the risk to the affected community as high, requiring efforts to reduce deaths from infections, reduce malnutrition, and improve malaria control. It said the risk to the DRC, region, and rest of the world is low due to the localized nature of the outbreak.