Live at ECCMID: Day 2

Sundays are usually restful –  but not if you’re at ECCMID! It was a busy day to say the least, running between sessions, our booth (B5-42), and filming – but I’ve somehow managed to find time to bring you a quick summary of (some of) the great talks I attended.

 

Year in infectious disease

 

Mary Horgan covered four major viral topics in her talk – HIV, herpesvirus, mpox, and COVID-19 and other respiratory viruses – while Jaime Labarca covered bacterial infections, antimicrobial resistance (AMR) and treatment, immunosuppressed patients and fungal infections, and mycobacterial infections. Below, I share highlights from their presentations.

 

Mary Horgan, Ireland

 

Cabotegravir for the prevention of HIV-1 in women: results from HPTN 084, a phase 3, randomized clinical trial

 

In a phase 3 study with females at risk for HIV, cabotegravir (CAB) administered every eight weeks proved to be effective in preventing HIV. The findings were truly stark – there were only four incident cases in those that received CAB, compared with 36 in the daily oral tenofovir diphosphate plus emtricitabine (TDF-FTC) group, showing that CAB is effective in preventing HIV in high-risk women and superior to TDF-FTC.

 

Combination anti-HIV antibodies provide sustained virological suppression

 

Searching for an alternative to the current daily antiretroviral therapy (ART) regimens, researchers explored combination therapy of two or more broadly neutralizing antibodies (bNAbs). Combination therapy was shown to be highly effective in suppressing HIV; moreover, during virological suppression, no evidence of resistant HIV was found.

 

Longitudinal analysis reveals high prevalence of Epstein-Barr virus associated with multiple sclerosis

 

Is multiple sclerosis (MS) caused by Epstein-Barr virus (EBV)? In a groundbreaking paper that came out in April 2022, researchers studied 10 million young adults in the military, finding that the risk of MS increased 32-fold after EBV infection, but not after infection with other viruses. Their findings offer strong evidence for a viral connection between EBV and MS, leading the authors to suggest that EBV is the leading cause of MS.

 

Mpox virus infection in humans across 16 countries — April–June 2022

 

In the first large-scale study of mpox outside of endemic regions, researchers described the presentation, clinical course, and outcomes of PCR-confirmed mpox infection. The virus was most common in men who have sex with men, with sexual close contact as the most suspected route of transmission. Just under half of the individuals had well-controlled HIV infection. The study highlighted the importance of collecting and sharing information on the virus to control community spread.

 

Real-world use of nirmatrelvir–ritonavir in outpatients with COVID-19 during the era of omicron variants, including BA.4 and BA.5 in Colorado, USA: a retrospective cohort study

 

Real world data on the use of nirmatrelvir–ritonavir for treating COVID-19 showed the treatment reduced 28-day all-cause hospitalization, all-cause mortality, and emergency department visits. During an omicron surge, which included BA.4 and BA.5, the data provided evidence for using nirmatrelvir–ritonavir as a first-line treatment for adults with acute SARS-CoV-2 infection.

 

Risk of Alzheimer’s disease following influenza vaccination: A claims-based cohort study using propensity score matching

 

Good news if you’re over 65 and routinely get your flu shot – in the final paper presented in Horgan’s session, scientists found that influenza vaccination is associated with reduced risk of Alzheimer’s disease. Patients who received one or more flu vaccines were 40 percent less likely to develop Alzheimer’s disease during the four-year follow up. Why? Three hypotheses were offered: flu specific mechanisms influencing neuro-cognitive function; non-flu-specific training of the innate immune system; and non-flu-specific changes in adaptive immunity.

 

Jaime Labarca, Chile

 

SER-109, an oral microbiome therapy for recurrent Clostridioides difficile infection

 

In a phase 3 randomized control trial, researchers tested whether SER-109 was superior to placebo in reducing risk of C. difficile infection recurrence up to eight weeks post-treatment. In patients who had had three or more C. difficile infection episodes, the results confirmed their hypothesis and also showed that SER-109 has a similar safety profile to a placebo.

 

Global burden of bacterial antimicrobial resistance in 2019: A systematic analysis

 

Researchers estimated deaths for 23 pathogens and 88 pathogen-drug combinations in 204 countries throughout 2019. Almost five million deaths were associated with AMR and 1.27 million deaths were directly associated with AMR in 2019. The study represents the first comprehensive assessment of the global burden of AMR, but continuing to build on this knowledge going forward is crucial for more informed decision making.

 

Single-dose liposomal amphotericin B treatment for cryptococcal meningitis

 

Cryptococcal meningitis is the leading cause of HIV-related death in sub-Saharan Africa. In a study with HIV-positive adults in this region, single-dose liposomal amphotericin B combined with flucytosine and fluconazole was found to be noninferior to the WHO-recommended treatment for HIV-associated cryptococcal meningitis and was associated with fewer adverse events.

 

Shorter treatment for nonsevere tuberculosis in African and Indian children

 

In a study trialing shorter treatment regimens in children and adolescents with tuberculosis (TB), the intervention group received the four-month treatment regiment while the control group received the six-month regimen. There was no difference in outcome or adverse events between the groups, and the four-month treatment was non-inferior at a 72-week follow-up. The study was a particular highlight of Labarca’s talk as it brought about meaningful change in the WHO guidelines for TB – shortening treatment from six to four months in children and adolescents with non-severe TB.

 

Learning from the past: paleomicrobiology

 

How to analyze a sample that is 1000 years old

 

Johannes Krause, Germany

 

Little is known about the early evolution of pathogens, evolutionary rates of pathogens, and how humans have adapted to pathogens over time. Why? Unlike dinosaurs and other ancient creatures, we don’t have fossils of pathogens to study, so we don’t know much about how they change through time.

 

In his talk, Johannes Krause (Max Planck Institute for Evolutionary Anthropology, Germany) introduced us to ancient pathogen genomics – the field of reconstructing pathogen genomes. Excitingly, this area of study can show us molecular fossil records for pathogens, host-pathogen interactions over time, long-time mutation rates, and help us identify the causative agents of historical pandemics.

 

Today, though, Krause focused on Yersinia pestis, the causative agent of plague. Bubonic plague is a rodent disease transmitted between rodents by fleas; whereas pneumonic plague affects the lungs and is transmitted through the air. Although antibiotics help us effectively treat it, bubonic plague still exists today.

 

Y. pestis caused three historic plague pandemics:

• Plague of Justinian (541)
• Black Death (1348–1352)
• Yunnan/Hong Kong (1855–1959)

Presenting a myriad of research throughout the talk, Krause reports that, 5,000 years ago, Y. pestis had a large deletion in its genome and lacked some of the genes necessary to be transmitted by fleas, meaning it couldn’t cause bubonic plague. Fast forward to 3,800 years ago, these genes sprang into existence. What’s more, Y. pestis from 700 years ago is the common ancestor of today’s modern strains – indeed, the mother of all strains. Krause notes that if you take the strains circulating today back in time, they would probably cause the Black Death… 

 

According to Krause, the Black Death can be traced back to the 1330s on the foothills of the Tian Shan – in what’s now Kyrgyzstan. When tested, the strain that supposedly came from Eastern Europe had only one mutation less than the Black Death strain found in London – and, from analyzing a large number of strains from the Black Death in Spain, France, Germany, and London, Krause reports that they are all 100 percent identical.