1/ #Marburg virus is a deadly relative of #Ebola. How certain people get infected and others don't despite similar exposures is a question we are investigating. I was reviewing an old case from a returned traveler in Colorado in 2008. This was the first ever imported case of a filovirus infection in the United States. So how did she get infected? cdc.gov/mmwr/preview/m…
2/ At first, the patient never received an accurate diagnosis and had ongoing symptoms for months. Apparently, she herself requested testing for Marburg 7 months later after reading about a fatal case in a European traveler who had visited the same caves that she had in Uganda.
The 'Python Caves' in Uganda have roosts of fruit bats which are known to shed the virus. She reported only being in the cave for about 15-20 minutes and her husband was with her as well (he didn't get sick)
3/ No one else on the tour contracted disease. During in-depth interviews, what they discovered was that she was the only person who reported actually touching rocks that had bat guano (feces) and she reports that she may have then covered her nose with the same hand because of a strong smell in the caves.
New paper @JAMA_current — one of the authors is @Stanford Professor Dr. Luby who led the Bangladesh RCT on community masking & *many* other RCTs in global health- a leading expert in this field
“Well-designed observational studies have demonstrated the association of mask use with reduced transmission of SARS-CoV-2 in community settings, and rigorous evaluations of mask mandates have found substantial protection”
2/ Well designed randomized controlled trials are often not possible for all types of interventions
“Disagreement about whether face masks reduce the spread of SARS-CoV-2 has been exacerbated by a focus on randomized trials, which are limited in number, scope, and statistical power. Many effective public health policies have never been assessed in randomized clinical trials; such trials are not the gold standard of evidence for the efficacy of all interventions.”
3/ Full disclosure— I am a member of the Luby lab at Stanford where I am leading an RCT of air filtration/ventilation in a real world setting to study household transmission of SARS CoV 2. The trial is teaching us a lot about how DIY air filters work outside of lab settings (inherently imperfect use).
I often get asked why someone’s spouse got infected with #covid19 & they didn’t despite sleeping in the same room (or variations of this question). I think infectious disease epidemiology can be a very confusing field for the general public (this being a good example —> what might seem otherwise like a logical transmission pathway doesn’t give you the outcome you expected) & this inherently lends itself to risk of misinformation taking hold.
In many outbreak investigations (a number of examples from outside the US), people often highlight how ‘cultural’ views of disease spread may make communities resistant to biomedical explanations (an oversimplification but there are many anthropological studies that elucidate this tension)
But I think infectious disease transmission events are inherently very complex. They depend on the host shedding pathogen effectively; the contacts being exposed in a particular way at the right time; immune system aspects; environmental contributors (air quality etc); the diagnostics used & much more.
1/ Tpoxx (Tecovirimat) resistance in immunocompromised patients, many of whom received multiple courses of treatment. Reminder- tpoxx is our first-line antiviral against monkeypox/mpox.
2/ Having worked on surveillance for a number of cases for the past several months, I think key is that many are patients also w/ tough social challenges which have made adherence to antiretroviral medications difficult, setting them up for a double-hit with AIDS + mpox @g0ingmad
3/ Health equity again is at the core of epidemic response. Over time, it is possible that we see circulation of these #mpox variants even in patients who have not been exposed to tecovirimat yet (more on this soon), esp if we see a resurgence this year. @gregggonsalves
1/ Phenomenal lecture today from Dr. Stephen Luby on his team's work discovering the mechanisms of #NipahVirus transmission in Bangladesh over nearly the past two decades
2/ They asked the families of deceased cases about many exposures; & similarly asked the same to neighborhood controls
The evidence here pointed to consumption of raw date palm sap (odds ratio of 7.9)
Bats were suspected to drink from/near the clay pots of sap in the trees
3/ They used infrared cameras to help add to the evidence base, showing Pteropus bat behaviors at night related to consumption of the date palm sap where they presumably shed live virus. pubmed.ncbi.nlm.nih.gov/21207105/
If we were hit with another covid-like pandemic soon, are we ready? As USG & (likely soon) WHO end the "emergency" phase of #Covid19, we need to avoid panic-neglect cycles. I think this is the bigger emergency. @bmj_latest
2/ As much as this is a matter of public health, it is also (perhaps more) a matter of politics. What will a Republican-led House focus on/fund for pandemic preparedness? And, w/ elections next year, to what extent will prevention efforts get pushed further down priority list?
3/ Furthermore, while we have excellent vaccines, more attention on high-quality masks, & some movement toward cleaner air, each of these areas is plagued by serious challenges in implementation.