A recent issue of the New England Journal of Medicine had an editorial (not a research paper) titled “Strategic Masking to Protect Patients from all Respiratory Viral Infections”. It was written by four Harvard physicians whose specialty is epidemiology and public health.
The authors preamble alludes to the understandable mask wearing pushback/mask use fatigue in both the general population and in healthcare workers. That’s very understandable. We are all sick of constraints. But the focus of the article is with the first word: “strategic”. They make a rational argument for what they call strategic masking. Myriads of studies during the Covid 19 pandemic came to diverse findings on mask benefit. From “doesn’t seem to do much” to “has a major impact on transmission”. The authors point out that the naysay findings are probably due to inappropriate mask type or improper use. How many times have you seen people wearing a mask covering their mouth but not their nose. Duh! Collating all the data it seems that there is up to a 60 to 70% effectiveness of preventing viral transmission with masking. This includes the SARS-COV-2 virus along with other pesky viruses: influenza, RSV, human metapneumovirus, parainfluenza and rhinovirus. One fifth of patients hospitalized for pneumonia have a viral pathogen not a bacterial one. Influenza alone accounts for 50 to 60 thousand deaths a year in the US.
The strategies they offer are several. One is to consider mask use in public places and health care facilities during months of the year with high viral illness. Another is to consider universal masking in health care settings when patients being attended to are at a higher risk due to age or underlying premorbid conditions.
My own personal experience does not constitute science. But prior to Covid-19 and mask use this aging physician was catching two to three viral respiratory infections a year. Since my mask use over the past 4 years, I have not been sick.
Finally, a medical therapy I can relate to. I love ice cream. Actually, it’s not a medical therapy, but a safe mechanism to “test the waters” in alpha-gal syndrome. This newsletter has previously discussed this uncommon condition that unfortunately is becoming more common. By way of reminder the syndrome is the new onset of anaphylaxis due to eating meat. It is a strange condition in that the allergic symptoms occur suddenly (hives, swelling, throat constriction) but are delayed 3 to 6 hours from the meat ingestion. It’s kind of similar to touching a hot stove and then feeling the sudden pain hours later. The reason it develops is due to allergic sensitization from a tick bite. The other peculiar aspect of the syndrome is that the allergic issue usually doesn’t develop for several months after the tick bite. Thus, people often don’t associate the two. The tick saliva contains a molecule called alpha-gal which is also found in meat, especially beef and pork. The diagnostic test is to draw blood and see if there are antibodies to alpha-gal. An antibody level greater than .10 IU/L makes the diagnosis “possible” and a level greater than 2 IU/L is definitive.
If a patient avoids further tick bites this antibody level can decrease over time. Once it has decreased enough then the likelihood for reaction goes away. So it is in this setting that the ice cream test comes in to play. High fat ice cream has a very small amount of alpha-gal, so if ingesting it turns out to be safe, then the patient can feel greater comfort returning to meat.
I guess I can justify my nightly ice cream dessert as a proof that I’m not developing alpha-gal.
The Florida Department of Health has issued a statewide mosquito advisory. In the past two months there has been an increasing number of malaria cases in the state. Malaria is transmitted by infected Anopheles mosquitos. The Florida cases have all been due to these mosquitos transmitting Plasmodium vivax. So far, there have been no deaths but several people required hospitalization.
The health department recommends reducing the chance for bites by wearing long pants and sleeves and using repellant (either on skin or on clothing) especially at dawn and dusk when mosquitos are most active. They also recommend “cover and drain” measures to eliminate standing water where mosquitos breed: garbage cans, house gutters, buckets, pool covers, flowerpots and plastic children’s pools.
The symptoms of malaria include; fever, chills, sweats, nausea, vomiting and headache and should prompt individuals to seek immediate medical treatment.
I’ve been privileged to be in the medical field since the discovery of Lyme disease and witness the ongoing research to understand it and to treat it. I happened to be an intern at Yale when a mother returned her child to the medical center insisting that the original diagnosis of juvenile rheumatoid arthritis, they had received on their initial visit might not be correct. After her first visit, she returned home to Old Lyme, Connecticut and by talking to neighbors found out that several other children in her neighborhood had gone to Yale and received the same “rare diagnosis”. A team of epidemiologists was dispatched to Old Lyme and indeed found a number of additional cases.
Thus, the research ball started rolling. I’ve often thought the illness should have been named after that intrepid mother rather than the town.
Lyme disease is caused by the bacteria Borrelia burgdorferi. Initially, the bacteria and the disease were limited to New England but have spread throughout the eastern states including Florida.
A vaccine for humans was developed and became available in 1998. But since consumer demand was low it went out of production in 2002. But because of increasing cases in the US a new vaccine is undergoing clinical trials by Pfizer pharmaceuticals.
Meanwhile, a different strategy is being implemented, a vaccine for mice. Mice are one of the most important reservoir hosts for Lyme disease. Living in the wild they transfer the bacteria via the ticks they carry and the ticks’ progeny.
The mouse vaccine is in edible pellets. It’s interesting that both the human vaccine and the mouse pellet vaccine contain a protein called OspA which is found on the surface of B.burgdorferi. The OspA spurs antibody production in the vaccine which in turn prevents infection.
A recent five-year study done in New York state using the mouse pellets found a 23% reduction in infected ticks after two years of distributing the pellets and a 76% reduction after five years.
Tezepelumab-ekko (Tezspire) is the first and only biologic agent approved by the FDA for severe asthma that is not limited to a specific asthma phenotype.
Biologic agents have ben a true god-send in terms of helping patients with severe asthma. The underlying cause for asthma is inflammation. But the cause of the inflammation varies from patient to patient. This variability is where the term phenotype comes into play. Identifying the specific immune mechanism that instigates the inflammation and thus the asthma has proven extremely useful. There are already a number of biologic agents that are extremely effective but to date they tend to target a single specific inflammatory mediator. In most cases that is all that is required. However, asthmatic inflammation can sometimes be multifactorial or what is referred to as a cascade effect. Think of dominoes falling into one another. This is where Tezepelumab-ekko can have utility.
Of course, every coin has two sides. With its broader impact on immune modulators there is also a potential for reducing desirable immune function. If a patient had a helminth infection this could worsen. Also, live vaccines must be avoided.
My favorite companion on woodland hikes (other than my wife and dogs) is my Leatherman, the ultimate multitool. It seems that the biologic agent dupilumab (Dupixent) is also becoming a multitool. It was initially approved by the FDA for people with severe eczema (atopic dermatitis). It works by preventing the inflammatory eosinophils from entering the skin. But since eosinophils also cause other types of allergic inflammation dupilumab’s role has expanded to include severe asthma, chronic rhinosinusitis with polyposis, eosinophilic esophagitis, and urticaria. It is both an expensive and potent medicine so it is not considered a first line treatment for any of these conditions.