A review and meta-analysis of studies on treatment outcomes for extensively drug-resistant tuberculosis (TB) found a success rate of only 44%, researchers reported yesterday in the Journal of Infection.

Among 5,056 studies published from 2005 to April 2023 that reported on treatment outcomes for extensively drug-resistant TB, researchers from Aarhus University Hospital in Denmark identified 94 eligible studies from 26 countries, involving 10,223 patients. The pooled proportion of cases treated successfully was 44.2% (95% confidence interval [CI], 38.3% to 50.3%), well below the World Health Organization (WHO) target success rate of 75%. For studies in which all successful and unsuccessful outcomes were completely stratified, the pooled success rate was only 26.9% (95% CI, 19.1% to 36.4%). A variety of sensitivity analyses produced similar estimates.

"These rates are very low, and this situation is comparable to the prognosis for patients affected by tuberculosis prior to the antibiotic era," the study authors wrote.

They note, however, that a slight improvement in treatment outcomes was observed after 2013, and that the 25 studies on outcomes for patients with pre-extensively drug-resistant TB found a pooled treatment success rate of 63.3%.

This situation is comparable to the prognosis for patients affected by tuberculosis prior to the antibiotic era.

More important, the review did not include any studies conducted since the introduction of the all-oral, shorter, and less toxic BPaL (bedaquiline, pretomanid, and linezolid) regimen with or without moxifloxacin, which has demonstrated treatment success rates of up to 90% in phase 3 trials. The WHO recommended this regimen for most patients with drug-resistant TB in May 2022.

"This newly introduced and recommended regimen gives hope for a new era of extensively drug-resistant tuberculosis treatment," the authors wrote.

Analysis of Neisseria gonorrhoeae isolates from three African countries found high resistance to ciprofloxacin and emerging resistance determinants for azithromycin, African researchers reported today in the Journal of Antimicrobial Chemotherapy.

For the study, the researchers conducted antibiotic susceptibility testing and whole-genome sequencing (WGS) on 433, 154, and 99 gonococcal isolates collected from men in Uganda, Malawi, and South Africa, respectively, from 2015 to 2020. Although the World Health Organization African Region has some of the highest prevalence of gonorrhea, there data are scarce on antimicrobial resistance (AMR) and on the evolution, molecular epidemiology, and presence of genetic AMR determinants in gonococcal isolates from the region.

Antibiotic susceptibility testing revealed that resistance to ciprofloxacin was high in all countries (57.1% of isolates in Malawi, 77.8% in South Africa, and 100% in Uganda were resistant), while all isolates were susceptible to ceftriaxone, cefixime, and spectinomycin, and 99.9% were susceptible to azithromycin.

WGS found that AMR determinants were common for ciprofloxacin, benzylpenicillin, and tetracycline but rare for ceftriaxone and azithromycin. A phylogenomic tree of the isolates from the three countries, along with 159 isolates from Kenya and 52 from Burkina Faso, showed that most belonged to the more antibiotic-susceptible lineage B (780 isolates) compared with the AMR lineage (141).

It is imperative to strengthen gonococcal AMR surveillance, ideally including genomics, in African countries.

The study authors note that while ciprofloxacin is no longer recommended for gonorrhea treatment in the three countries, the high prevalence of ciprofloxacin resistance is likely related to its continued empirical use for urethritis, along with the continued use of fluoroquinolones for other infections. And although susceptibility to ceftriaxone and azithromycin was high, the existence of AMR determinants to these antibiotics, which are recommended for gonorrhea treatment, is a concern.

"The high prevalence of resistance to ciprofloxacin (and empirical use continues), tetracycline and benzylpenicillin, and the emerging resistance determinants for azithromycin show that it is imperative to strengthen gonococcal AMR surveillance, ideally including genomics, in African countries," they wrote.

Vaccine effectiveness (VE) among nursing home residents up to date on their COVID-19 vaccines is 31.2%, according to new research in Morbidity and Mortality Weekly Report.

In today's study, up-to-date vaccination was defined as receipt of a bivalent (two-strain) COVID-19 mRNA vaccine dose or completion of a primary series within the preceding 2 months. COVID-19 infections with Omicron strains documented from November 20, 2022 and January 8, 2023, in the National Healthcare Safety Network (NHSN) were included in the analysis.

"The study period was chosen to coincide with both the inclusion of bivalent vaccine in the definition of up-to-date status and the increase in COVID-19 infections during the winter months," wrote the authors, from the Centers for Disease Control and Prevention (CDC) and elsewhere.

The study included 108,727 weekly reports from 14,464 nursing homes. Overall, 4,314,714 (48.1%) nursing home resident-weeks reflecting up-to-date vaccination status, and 52,853 (40.6%) of COVID-19 patients were up to date.

It is important that nursing home residents stay up to date with COVID-19 vaccines.

After adjusting for weekly incident case counts (stratified by up-to-date vaccination status) with weekly resident counts (stratified by up-to-date vaccination status) each week during the study period, up-to-date VE against infection was 31.2% (95% confidence interval, 29.1% to 33.2%).

"It is important that nursing home residents stay up to date with COVID-19 vaccines and, if eligible, receive an additional bivalent dose to optimize protection against infection and related complications,” the authors concluded.