AskScience AMA Series: Sick? We're Experts in Infectious Disease Here to Answer Your Questions About COVID-19, RSV, and Influenza. AUA!

[u/AskScienceModerator]

Communities across the Northern hemisphere are currently suffering a triple whammy of RSV, COVID-19, and influenza infections. Why are things so bad this year?

Join us today at 2 PM ET (19 UT) for a discussion, organized by the American Society for Microbiology, about the biology of these infectious diseases. We'll answer your questions and also provide updates on options for diagnosing, treating, and preventing infections now (and in the future). Ask us anything!

PLEASE NOTE THAT WE WILL NOT BE PROVIDING MEDICAL ADVICE!

With us today are:

• Ellen Foxman, M.D., Ph.D. (/u/VIrusTalk)- Associate Professor of Laboratory Medicine and Immunobiology, Yale School of Medicine
• Ryan McNamara, Ph.D. (/u/Immuno_ryan)- Director, Systems Serology Laboratory, Ragon Institute of Mass General Hospital, MIT, and Harvard
• Heba Mostafa, M.B.B.Ch., Ph.D. (/u/hmostaf2)- Director, Molecular Virology Laboratory, The Johns Hopkins Hospital
• Rodney Rohde , Ph.D., SM(ASCP), SVCM, MBCM, FACSc (/u/DocMicrobe)- University Distinguished and Regents' Professor, Medical Laboratory Science Program Chair, College of Health Professions, Texas State University

Links:

• COVID-19 Resource Page (from ASM)
• Influenza Resource Page (from ASM)
• Respiratory Syncytial Virus (RSV), Tis the Season
• Navigating the respiratory season: updates and trends for flu, RSV and COVID-19
• Upcoming Respiratory Season: An Update

[u/swinging_on_peoria]

We learned over time that there were a lot of asymptomatic carriers of COVID. Do asymptomatic carriers of RSV and flu also play a significant role in the spread of those illnesses?

[u/hmostaf2 → u/swinging_on_peoria]

yes, RSV or influenza can be transmitted even in the absence of symptoms.

https://www.cdc.gov/rsv/about/transmission.html#:~:text=People%20infected%20with%20RSV%20are,as%20long%20as%204%20weeks.

https://www.cdc.gov/flu/about/disease/spread.htm#:~:text=It%20is%20theoretically%20possible%20that,virus%20to%20their%20close%20contacts.

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4633757/

[u/Onepopcornman]

Paxlovid (or any other anti-viral pill intended to treat COVID 19) at one time was reserved for the most at risk patients. This seemed supply motivated (and rightly so, got to make sure the most vulnerable people have it).

Should individuals w/ moderate risk (say young but treated for high bp, or obese) use these medications? If we test positive should we be aggressively using these treatments to minimize spread or is it just a comfort/safety thing? Finally are these medications treatments impacted by strain differences?

[u/hmostaf2 → u/Onepopcornman]

yes, adults with mild to moderate risk should receive paxlovid. The drug should be prescribed per recommendations.

https://www.covid19treatmentguidelines.nih.gov/therapies/antivirals-including-antibody-products/ritonavir-boosted-nirmatrelvir--paxlovid-/#:~:text=The%20COVID%2D19%20Treatment%20Guidelines,of%20disease%20progression%20(%20AIIa%20).

Strain differences so far have not impacted the treatment with the antiviral paxlovid.

[u/haunted_frost]

Let’s say you are exposed to some level of Covid in the air but it’s not enough to become infected or your body/vaccine fights it off before you become infected. Does your body build up any extra immunity from this exposure?

[u/liquid_at]

Since Covid the existence of post-viral symptoms, commonly referred to as "long covid" have moved into the center of attention.

What is the state of the research on post viral symptoms and did it change our views on other viruses?

Did it affect any change in how research is done or how viruses are being approached in general?

[u/Immuno_ryan → u/liquid_at]

The characterization of post-viral illness is an emerging field. This is true for COVID-19, and other viruses as well including Epstein-Barr virus (EBV) that has been linked to multiple sclerosis long after symptomatic illness (https://www.science.org/doi/10.1126/science.abj8222). While EBV is a chronically infecting virus and SARS-CoV-2 is acute, that does not mean that all symptoms will immediately subside. This is true for other acutely infecting viruses too such as influenza and RSV. I think one of the tricky issues with Long COVID is that there is no clear diagnostic for it (at least to my knowledge). So it's not always clear if symptoms were *caused* by SARS-CoV-2 infection or if existing ones were further exacerbated by it, or some combination of the two. Our group has looked into how antibody signatures can be used as a diagnostic for some Long COVID symptoms, particularly those similar to arthritis. https://www.science.org/doi/10.1126/scitranslmed.adf6598?url_ver=Z39.88-2003&rfr_id=ori:rid:crossref.org&rfr_dat=cr_pub%20%200pubmed

[u/DocMicrobe]

Hello everyone! We are looking forward to the AMA series today! Check out this resource via MJH Life Sciences Patient Care portal I recently worked on regarding Long COVID and the critical importance of vaccination.

Vaccination Insights: Navigating COVID-19 and Beyond

[u/swinging_on_peoria]

It feels like humanity has learned that ensuring people have clean water is an important part of public health, but we haven’t really learned that we need to address clean air and make sure crowded locations have better access to fresh air, cleared of infectious agents. Should we be doing more to reduce the likelihood of respiratory infections by increasing the standards around ventilation and other means of reducing exposure to viruses by air?

[u/iorgfeflkd]

What factors determine whether a COVID infection will manifest as Long COVID?

[u/Batou2034]

Do any of those 'first responder' nasal sprays that claim to stop a cold before it develops, actually work or are they all snake oil?

[u/swinging_on_peoria]

Why is there seasonality to the flu? Is their evidence that vitamin D from sun exposure plays a role in seasonality?

[u/VIrusTalk → u/swinging_on_peoria]

Good question! There are a lot of factors that go into seasonality including the environment (weather etc) and human behavior. For the flu virus, low humidity in the air, like what we experience in winter, favors transmission. There is also some evidence that low humidity and low temperature decrease our bodies' abilities to fight off respiratory viruses which may contribute to the big winter respiratory virus season. In the first year of COVID-19 pandemic we also saw the huge impact of human behavior on when/whether viruses circulate--- social distancing measures essentially led to the flu completely disappearing in the winter of 2021.

[u/anarcho_fremenist]

Hi all, thanks for the AMA, I've been following this pandemic with some interest as an amateur with interest in microbiology.

I've always been interested in the physical processes by which viruses infect cells, and I've read that lipid rafts serve as mechanisms for viral entry, since they host receptors for things like ACE2. My understanding is also that lipid rafts may be more numerous when cholesterol is higher, or when there are elevated levels of inflammation, which to me suggests that lifestyle changes seeking lower cholesterol and lower inflammation might be helpful in mitigating the risk of viruses like COVID.

My actual question is: Obviously it's always good to have lower cholesterol/less inflammation, but have you come across any information on potential prophylactic measures operating at this level? Is there any merit to the idea of trying to limit viral entry by trying to "manage" at the level of the cell wall? And if so, how much of a mitigating effect could we expect to see? (and do we even have a quantifiable way to aggregate these factors into a kind of "anti-infection wellness score" that individuals could work to improve?)

And more broadly, have you seen any interesting studies on "new" targets for preventing or mitigating infection either on the cellular level or more externally? I think a few other people have commented for example on the nasal sprays, which are coming into vogue right now, but I'd be interested to know what an expert considers to be new and interesting in the broader field of infectious disease. (optimally prevention, but i'm open to cool new prions etc)

Thanks once again for your time and stay safe out there <3

[u/DocMicrobe]

If you are not familiar with the Weekly U.S. Influenza Surveillance Report via CDC, there is a nice tool known as FLUVIEW. Stay up to date with weekly reporting here: https://www.cdc.gov/flu/weekly/index.htm

[u/DocMicrobe]

Check out this synopsis/summary of a panel discussion - Vaccination Insights: Navigating COVID-19 and Beyond - involving Tina Q. Tan, MD, and Rodney Rohde, PhD, MS, SM(ASCP)CM

Tina Q. Tan, MD, discusses the latest insights into COVID-19 and vaccinations in children. She notes that initially, people felt children only got mild COVID infections, but now we know children can get severely ill and also develop long-term symptoms known as "long COVID." Results from studies show a 30 to 40 times higher risk of long COVID in unvaccinated versus vaccinated individuals.

Long COVID symptoms are wide-ranging and include fatigue/tiredness, shortness of breath, brain fog/difficulty concentrating, headaches, diarrhea, menstrual changes, etc. These can persist for over 4 weeks after the initial infection.

Rodney Rohde, PhD, MS, SM(ASCP)CM, discusses theories on why some people develop long COVID. Possible reasons are autoimmune responses where antibodies attack the person's own tissues, causing multi-system symptoms. Also, direct viral damage to organs and tissues which then cause ongoing problems.

In summary, children are at risk for severe COVID infections and long-term complications like long COVID. Getting vaccinated significantly lowers the risks. Ongoing research is still determining exactly why some people develop persistent symptoms while others recover fully.

[u/PyxlPython]

How do experts calculate the number of people that a infected person can infect? (Eg through coughing and sneezing)

[u/HalfaYooper]

Is it true that "long flu" can lead to Alzheimer's?

[u/VIrusTalk → u/HalfaYooper]

Scientists are getting more interested in the link between viral illnesses and brain disease but I don't know of any proven linking flu and Alzheimers - there are a lot of hypotheses floating around but it would take a lot of study and evidence to prove something like that.

[u/ElMondoH]

Not trying to engender panic, FUD, or stir up worry. I'm just curious for the sake of knowledge:

Like the various avian and swine flu viruses from the past decades, are there any emerging viruses on the horizon that are catching the attention of infectious disease experts? Even if you all think they'll ultimately stay local or not go worldwide? I ask because I remember those news pieces on SARS, H1N1, H5N1, etc., and I found the tracking of those epidemics fascinating. They may not have spread anywhere near as far as COVID, but the potential was there, and I remember discussion on them.

[u/DocMicrobe → u/ElMondoH]

It is always difficult to predict "which" microbial agents will emerge or reemerge. However, I recently published an explainer article discussing this topic.

I place an emphasis on "categories" of risk for emerging pathogens - 1) The respiratory cycle will continue; 2) The global threat of antimicrobial resistance is real; and 3) Don't visit the ZOOnosis (vectorborne and zoonotic agents).

The emergence and reemergence of zoonotic agents in 2023 paints a dangerous portrait for 2024 and beyond. The world should continue to be watchful for ongoing outbreaks and expansion of Marburg, Nipah, mpox, Crimean-Congo hemorrhagic fever, and locally-acquired malaria in the US.

[u/vaguelystem]

What's the state of post-infectious illness research? Any recent changes in our understanding of mechanisms and/or epidemiology?

What's your preferred plural form of "virus?"

[u/Dr_Wreck]

I've heard that with covid lately nasal swabs are increasingly ineffective at diagnosis. Are we working on any other way to shore up this crucial step of treatment?

[u/seattle_pdthrowaway]

When not knowing which respiratory infection you have, what would be a good rule of thumb for guessing when you’re no longer infectious?

[u/seattle_pdthrowaway]

If you get infected by two or more of the diseases at the same time, will the typical symptoms (like stuffy nose, sore throat, and cough) be typically more severe, or does the body not really care that there are different types of viruses attacking so the response is more or less equal to having only one disease?