We’re in hot water! Vibrio vulnificus infections are heading north

By Warren R. Heymann, MD
Dec. 16, 2020
Vol. 2, No. 49

When driving to work, I usually listen to our local 24-hour news station, paying half-attention as I’m mentally sorting out the upcoming day’s agenda. Upon hearing a report of several cases Vibrio vulnificus (Vv) at my hospital (Cooper University Hospital, Camden, NJ; KYW 1060, June 17, 2019) it was hard to concentrate on the road.

From 2009 to 2017 there had only been one case of Vv infection at Cooper. Although reports of Vv infections after exposure in the Chesapeake Bay are not uncommon, cases from exposure in the cooler Delaware bay were considered rare. King et al reported 5 cases of Vv necrotizing fasciitis from Cooper that occurred during the summers of 2017 and 2018 after water exposure in the Delaware Bay (4 patients) and/or consumption of crabs from the Delaware Bay (3 patients); 4 patients survived. (1)

Vibrio vulnificus is a Gram-negative, bacterial pathogen commonly living on plankton and shellfish, especially oysters, which grow in water at temperature between 15 and 27 °C and salinity from 0.7 to 1.6% of the harbor, river, and sea junctions as well as inland salt lakes. Humans can be infected after eating seafood contaminated with Vv or direct contact in a wound. Vv–associated sepsis is a fatal disease with a mortality rate over 50%, being more severe in patients with chronic liver disease. It is highly prevalent in some coastal cities in the U.S., Japan, and Taiwan. (2)

Risk factors for severe infection include hepatitis B and C infection, liver disease (including cirrhosis, hemochromatosis), end-stage renal disease, diabetes, HIV malignancies, and immunocompromised states (including iatrogenic immunosuppression). (3,4,5) Interestingly, in up to 10% of cases of Vv infection and exposure cannot be determined. (3)

Vv infection is acquired gastrointestinally or percutaneously and is manifested through three distinct syndromes: primary septicemia, wound infection, or gastrointestinal disease. With primary septicemia, about half of the cases present with altered mental status and one-third are in septic shock. Most patients develop skin lesions after the first 24 hours. (6) For those with septicemia, bullous lesions may be observed. (4) Infection of a wound is a rapidly progressive cellulitis, associated with hemorrhagic blisters and necrotic lesions with possible evolution to necrotizing fasciitis. (6)

Patients with open wounds are at risk of infection. Guillod et al reported the case of an 85-year-old patient who developed lower limb cellulitis caused by V. parahaemolyticus, originating from leg ulcers and complicated by septicemia and septic shock, after a sea beach holiday at the Mediterranean Sea in Italy. Infection by V. parahaemolyticus may present similarly to Vv infection, although necrotizing fasciitis and sepsis are considered rare. (7)

The pathogenic mechanisms behind Vv infection are complex, and are likely multifactorial, a partial list including the organism’s capsular polysaccharide [acting as a biofilm], iron concentration (which inhibits the transcription of the major regulator of the quorum-sensing gene, affecting bacterial cell-cell communication), and virulence factors (cytolysin, metalloproteinase, AphB, and IL-8).

After confirming the diagnosis by culture (wound, blood) with appropriate susceptibility testing, the current recommendation for treatment is with a third-generation cephalosporin combined with tetracycline. Debridement and surgery (including amputation) may be necessary; patients with sepsis require ICU supportive care. (2)

In Philadelphia, the summer of 2020 was the third warmest on record, with an average temperature of 78.4 degrees Fahrenheit. “A lot of that warming trend comes down to the overnight low temperatures,” said Jonathan O’Brien, a meteorologist with the National Weather Service office in Mount Holly. The average minimum temperature for the three-month period, 69.9 degrees, was tied for second place. In New Jersey, the nights were the warmest on record, according to David A. Robinson, the state climatologist. The data go back to 1895. (8)

“We are indeed in hot water!” state Froelich and Daines. “Along with coastal flooding and the encroachment of saltwater farther inland comes an increased risk of human interaction with pathogenic Vibrio species, such as Vibrio cholerae, V. vulnificus and V. parahaemolyticus.” (5) (These authors get the credit for the title of this commentary!) Climate change is contributing to the expansion of infectious diseases into areas that were previously spared of these disorders — this is true for vector-borne illnesses, and as these reported Vv cases depict, water-borne illness also. Clinicians must be cognizant of these epidemiologic trends, and the implications of climate change must be addressed.

Point to Remember: Vibrio vulnificus infections are potentially fatal infections. Because of the warming climate, these cases may be coming to a hospital near you. To save a life, dermatologists must recognize the predisposing factors of Vv infection, and the cutaneous manifestations related to direct cutaneous infection and/or sepsis.

Our Experts’ Viewpoints

Markus D. Boos, MD, PhD
Assistant Professor, Pediatrics, University of Washington School of Medicine
Attending Pediatric Dermatologist, Seattle Children’s Hospital

Watching the steady rain from my kitchen table on an overcast Seattle morning, I feel gratitude. In the summer of 2020, the entire West coast was choked by the thick smoke of uncontrolled wildfires, physically and mentally stressing communities that had already been depleted by simultaneously responding to the twin ills of structural racism and COVID-19. My family was lucky: though cramped and crabby as my 4th graders went to school on Zoom without the opportunity to play outside, we were far from the actual fires, and our air purifier kept us free from harm. I have had a lot on my mind this year, and an unprecedented wildfire season has heightened my concern for our collective future. The small detail that worried me the most, though, was an absence: in almost all media coverage of our mega wildfires and a record setting hurricane season in the Atlantic, the words “climate change” were missing.

They shouldn’t be. Climate change is an undisputable fact, and its roots in human activity, including the continued burning of fossil fuels, are certain. (9) According to the Lancet Countdown, the world has warmed over 1 degree Celsius since pre-industrial times, with certain areas of the globe warming over 3 degrees. (10) As such, children alive today are already being impacted by climate change, with adverse health effects expected as a result of environmental degradation across all ages and stages of that individual’s life. (10) If we are paying attention, we don’t need scientists to explain to us what is happening in our backyards — the world is changing, and loss of the environmental stability that has allowed humans to prosper puts us and our health at risk. Climate change is here and it is harming us, not in some vague “future” or “2100” scenario — but right here and now, across the country and the world.

How does this affect us as dermatologists? Climate change has myriad effects on the skin, from a greater risk of skin cancers to increased flares of inflammatory dermatoses and an expanded range of infectious diseases with cutaneous manifestations. (11) Sometimes effects are compounded: after Hurricane Katrina in 2005, there was an outbreak of Vibrio infections because the bacteria thrives in warm waters (in fact Vibrio has often been referred to as a “climate barometer”). (12) In my own practice, I continue to see uncontrolled flares of atopic dermatitis that were triggered when wildfire smoke reached our region. This came as no surprise to me as an entire body of literature has documented the effects of pollution, climatic variables, and stress on the incidence and prevalence of atopic dermatitis. (13) This summer and early fall is not going to be an aberration; it is my “new normal.”

Climate scientists continue to sound the alarm — we are imperiling our future as we continue to burn fossil fuels and warm the globe. What is currently a “record setting fire season” will actually be one of the coolest years for the next hundred, thousand, or tens of thousands of years, unless we collectively listen to experts, and rapidly decarbonize by transitioning off of fossil fuels. The term “new normal” is, in fact, falsely reassuring — while challenging, we can still manage "today." Nevertheless, it is essential to internalize that "today" is not just a top-three warmest year on record — but that this is the coolest it will be for the rest of our lives, and the lives of our children’s children’s children.

If you, like me, can’t wait for 2020 to be over, I have unfortunate news — this is just the beginning of rapid changes to our world that will continue to challenge us as physicians and individuals. Right now, our trajectory is grim, with record losses of polar ice and biodiversity, among other consequences of climate change, threatening our way of life. (14) Nevertheless, instead of despair, we can feel hope if we recognize the scope of this threat and our collective ability to respond to it. Small changes that we make in our personal lives (walking more, eating less meat, reusing and repurposing bags and other items) are noble goals that can signal shifts in cultural norms and inspire our colleagues to do the same. Taking the time to educate ourselves about the health effects of climate change and sharing that information with our patients in a non-judgmental manner contributes to a collective awakening to the magnitude of the crisis, in turn spawning greater “grassroots” activism. (15) Our greatest impact, however, comes from working as larger groups to push our local, state and federal governments, and even our professional organizations, to change. COVID-19 "lockdowns" briefly gave us cleaner air but also showed us the limitations of individual action. (16) CO2 emissions continue to rise — not dramatically fall, as climate science shows is necessary. Institutional, collective action is necessary to tackle this challenge.

Within the American Academy of Dermatology, the Expert Resource Group (ERG) on Climate Change and Environmental Advocacy has been working tirelessly to educate Academy leadership and members on the important role that dermatologists play in educating and combating the climate crisis. Through publications (including an entire issue devoted to climate change and cutaneous health to be published soon in the International Journal of Women’s Dermatology), (17) forums at our annual meeting, and partnerships with national organizations including the Medical Consortium on Climate and Health, the Climate Change ERG provides dermatologists an opportunity to interact with other like-minded providers to learn and educate one another about cutaneous health in the context of the climate crisis. In turn, the ERG hopes to turn that knowledge into a shift in individual perspectives and broader social policies that prevent our planet from falling further into disrepair.

The climate crisis should rightfully give us worry, but it is in my dual roles as a father and a physician that I find the purpose to engage in this work. Climate change has become politicized, but the science speaks for itself — our children, our patients and our future are in peril if we don’t recognize the enormity of this challenge and address it with urgency. It’s time for dermatology to have some skin in the game.

Katherine Doktor, MD, MSc
Assistant Professor
Division of Infectious Diseases
Cooper Medical School at Rowan University Cooper University Hospital

A wise medical school professor once said that a doctor cannot diagnose something that is not in his/her differential. That sage advice is especially pertinent when diagnosing the rapidly progressing necrotizing soft tissue infection caused by Vibrio vulnificus. Often presenting as painful erythema, it can be misdiagnosed as cellulitis if a good patient history is not obtained. Especially pertinent to the patient’s history is recent exposure to warm saltwater in the summer and early fall, a habitat in which Vibrio vulnificus thrives. Patients with liver disease, diabetes, or whose immune system is otherwise compromised are at increased risk for developing severe infection. As bodies of water warm as a result of climate change, the increased temperatures allow Vibrio vulnificus to proliferate in regions previously too cold to support its growth. Taking a thorough history and having a high index of suspicion, even in locations north of usual outbreaks, are key to preventing the highly morbid and sometimes fatal consequences of this infection.

1. King M, Rose L, Fraimow H, Nagori M, Danish M, Doktor K. Vibrio vulnificus Infections From a Previously Nonendemic Area. Ann Intern Med. 2019;171(7):520-521. doi:10.7326/L19-0133

2. Leng F, Lin S, Wu W, Zhang J, Song J, Zhong M. Epidemiology, pathogenetic mechanism, clinical characteristics, and treatment of Vibrio vulnificus infection: a case report and literature review. Eur J Clin Microbiol Infect Dis. 2019;38(11):1999-2004. doi:10.1007/s10096-019-03629-5

3. Gittens AT, Clarke JD, Abdelbaki S, Kwon JS. A 72-Year-Old Man With a Violaceous Rash and Sepsis. Chest. 2020;157(2):e41-e45. doi:10.1016/j.chest.2019.08.2186

4. Umakoshi N, Kuriyama A. Bullous skin lesions in Vibrio vulnificus infection. Emerg Med J. 2013;30(10):863. doi:10.1136/emermed-2012-202098

5. Froelich BA, Daines DA. In hot water: effects of climate change on Vibrio-human interactions [published online ahead of print, 2020 Mar 1]. Environ Microbiol. 2020;10.1111/1462-2920.14967. doi:10.1111/1462-2920.14967

6. Dupont L, González Guzmán AL, Guarda NH, Albarello L, Martins Souza PR. Vibrio vulnificus: report of a potentially fatal skin infection. Int J Dermatol. 2020;59(9):e317-e318. doi:10.1111/ijd.14991

7. Guillod C, Ghitti F, Mainetti C. Vibrio parahaemolyticus Induced Cellulitis and Septic Shock after a Sea Beach Holiday in a Patient with Leg Ulcers. Case Rep Dermatol. 2019;11(1):94-100. Published 2019 Apr 16. doi:10.1159/000499478

8. Wood AR. Summer of 2020 was third-hottest on record in Philly as warm-night trend continues. Philadelphia Inquirer September 2, 2020.

9. Santer, B. D. et al. Celebrating the anniversary of three key events in climate change science. Nat. Clim. Change 9, 180–182 (2019).

10. Watts, N. et al. The 2019 report of The Lancet Countdown on health and climate change: ensuring that the health of a child born today is not defined by a changing climate. Lancet Lond. Engl. 394, 1836–1878 (2019).

11. Kaffenberger, B. H., Shetlar, D., Norton, S. A. & Rosenbach, M. The effect of climate change on skin disease in North America. J. Am. Acad. Dermatol. 76, 140–147 (2017).

12. Centers for Disease Control and Prevention (CDC). Vibrio illnesses after Hurricane Katrina—multiple states, August-September 2005. MMWR Morb. Mortal. Wkly. Rep. 54, 928–931 (2005).

13. Hendricks, A. J., Eichenfield, L. F. & Shi, V. Y. The impact of airborne pollution on atopic dermatitis: a literature review. Br. J. Dermatol. 183, 16–23 (2020).

14. The IMBIE Team. Mass balance of the Greenland Ice Sheet from 1992 to 2018. Nature 579, 233–239 (2020).

15. Schachtel, A. & Boos, M. D. Pediatric dermatology and climate change: An argument for the pediatric subspecialist as public health advocate. Pediatr. Dermatol. 36, 564–566 (2019).

16. Le Quéré, C. et al. Temporary reduction in daily global CO2 emissions during the COVID-19 forced confinement. Nat. Clim. Change. 10, 647–653 (2020).

17. Silva, G. S. & Rosenbach, M. Climate change & dermatology: An introduction to a special topic, for this special issue. Int. J. Womens Dermatol. (2020) doi:10.1016/j.ijwd.2020.08.002.

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