Cutaneous manifestations of SARS-CoV-2 and COVID-19 vaccines

 COVID-19 is associated with a wide range of skin signs. 

The following six main clinical patterns have been proposed for such manifestations most recently: (i) urticarial rash, (ii) confluent erythematous/maculopapular/morbilliform rash, (iii) papulovesicular exanthem, (iv) chilblain-like acral pattern, (v) livedo reticularis/racemosa-like pattern, and (vi) purpuric "vasculitic" pattern. Livedo or necrosis - blotchy red or blue appearance with a net-like pattern - was associated with increased disease severity while measles-like (morbilliform) rash was generally seen in patients with moderate to severe infection (like in the patient shown on the left who died) and pseudo-chilblains, a late sign of COVID-19, was associated with decreased severity and more likely to happen for younger patients. The median duration of chiblain-like acral pattern, however, was significantly longer that all other patterns. One study of 200 patients found the following frequencies of these signs: 10.2% for Urticarial rash; 25.7% for confluent erythematous/maculo-papular/morbilliform rash; 15.5% for papulovesicular exanthem, 24.6% for a chilblain-like acral pattern; 2.1% for a livedo reticularis/racemosa-like pattern; and 6.9% for a purpuric vasculitic pattern. 15% of skin patterns were not clearly classified while 6.5% had more than one pattern present.

The prevalence of cutaneous involvement was 7.8% in a binational Chinese-Italian cohort of 678 hospitalized adults with laboratory-confirmed disease. Dermatologic reactions after COVID-19 vaccines have been also reported and can mimic SARS-CoV-2 infection itself (eg, pernio/chilblains). The prevalence was the highest after the 2nd dose of mRNA-1273 (over 12% in Moderna), although only 1-2% experienced it with ChAdOx1 nCov-19 vaccine (AstraZeneca).

Delayed large local reactions were most common among vaccinees, followed by local injection site reactions, urticarial eruptions, and morbilliform eruptions. In a study of 414 people, forty-three percent of patients with first-dose reactions experienced second-dose recurrence. Additional less-common reactions included pernio/chilblains, dyshidrotic eczema, psoriasiform dermatitis, cosmetic filler reactions, zoster, herpes simplex flares, and pityriasis rosea-like reactions. 

Some of more serious reactions could be exacerbation of Erythema multiforme. It mostly happens in mild form of a sudden rash that goes away in a few weeks but could progress to larger raised patches that look like a target or "bulls-eye" and may have a blister or crust. Relapses of autoimmune bullous disease have been also reported as well as new onset Lichen planus, immune complex vasculitis or flares of subacute cutaneous lupus erythematosus, psoriasis and atopic dermatitis. 

Morphologic misclassification is, however, possible. 

REFERENCES

Tan SW, Tam YC, Oh CC. Skin manifestations of COVID-19: A worldwide review. JAAD international. 2021 Mar 1;2:119-33.

Slimani Y, Abbassi R, El Fatoiki FZ, Barrou L, Chiheb S. Systemic lupus erythematosus and varicella‐like rash following COVID‐19 in a previously healthy patient. Journal of Medical Virology. 2021 Feb;93(2):1184-7.

Genovese G, Moltrasio C, Berti E, Marzano AV. Skin manifestations associated with COVID-19: current knowledge and future perspectives. Dermatology. 2021 Jan 1:1-2. 

Marzano AV, Genovese G, Moltrasio C, Gaspari V, Vezzoli P, Maione V, Misciali C, Sena P, Patrizi A, Offidani A, Quaglino P. The clinical spectrum of COVID-19–associated cutaneous manifestations: An Italian multicenter study of 200 adult patients. Journal of the American Academy of Dermatology. 2021 May 1;84(5):1356-63. 

Bogdanov G, Bogdanov I, Kazandjieva J, Tsankov N. Cutaneous adverse effects of the available COVID-19 vaccines. Clinics in Dermatology. 2021 Apr 27.

Rice SM, Ferree SD, Mesinkovska NA, Kourosh AS. The art of prevention: COVID-19 vaccine preparedness for the dermatologist. International journal of women's dermatology. 2021 Jan 12.

Human Body: A map of where Bacteria live

Who's The True You? A collaboration of our body and 100 trillion of microbes (bacteria, algae, yeast, protists and more) colonizing it.

Microbiota is specific to every individual, and varies systematically across body habitats and time, as well as geographical location, preventing or causing a disease after exposures to infectious agents.

Some human skin locations harbor even more diverse bacterial communities than the gut that we were thoughtfully nourishing with probiotics.

New analysis published in Science Express adds more information to the earlier results (from May 2009, for example), showing how diverse the microbiota is and how easy it is to re-colonize the skin.

We mapped some of the findings as shown in the Figure (on the right; the figure on the left maps bacteria in GI tract, from Dr. Richard Lord’s presentation at the 2008 Functional Medicine Symposium in Carlsbad, CA). Moist sites are shown with blue arrows, such as inside the nose, the armpits, the navel, dry areas are shown with green arrows, such as the forearm and oily sites are shown with yellow arrows: inside the ear, between the eyebrows, forehead, the back of the scalp.
Sites of most bacterial diversity were : The index finger, back of knee, forearm, palm and sole of foot.The forehead displayed the least diversity (with bacterial populations strongly preffering this site and not letting other bacteria to co-habit the space), but there were individual differences between different people. The mouth cavity showed the least variation in diversity both within individuals and between people. Studies of other microbes such as viruses and bacteriophages show low diversity in the airways as well, even though the human respiratory tract is constantly exposed to a wide variety of microbes and environmental agents. There is a difference between diseased and non-diseased individuals though - in Cystic Fibrosis (CF). for example, viromes are enriched in aromatic amino acid metabolism. Note that this disease causes a distinct acidic breath - the more severe the condition is in an individual, the more acidic his breath becomes. The microbes were especially sensitive to amino-acid starvation indicating that therapeutic measures may be more effective if used to change the respiratory environment, as opposed to shifting the taxonomic composition of resident microbiota.
Altered breath resulting from changed micrflora is a known phenomenon and it can be detected not only by complex mass spec machines, but also by devices used in QA testing of foods (e.g. Cyranose pick up the scent of penzane, isoprene acetone, and benzene in the breath of lung cancer patients) and car air quality sensors to study human "fermentome". (See also ongoing clinical trials on chemicals in human breath for diagnostics of diseases).

Altered bacterial populations could, indeed, be studied by metabonomic profiling. At present, however, the most accurate analysis, was performed based on microbial DNA or 16S RNA.
The study subjects were sampled four times each over a three-month period, typically after showering an hour or two earlier. Microbial DNA was then isolated directly from swabs used for sampling each body site. To recover bacteria from the skin surface, it was enough to swab it once by a wet cotton swab in 30s.