Evaluation of Epidemiological Problem: Vibria Vulnificus, Research Paper Example

Introduction

Vibrio vulnificus refers to a type of bacteria that belongs to the same family as the bacteria that causes cholera as well as Vibrio parahaemolyticus, although V. vulnificus infections are quite different from cholera. It usually inhabits warm seawater and belongs to a category of vibrios identified as “halophytic” because they need to live in saltwater (CDC, 2013). V. vulnificus is often insulated from oysters and shellfish in warm waters along the Gulf Coast during summertime. Because the bacteria thrives in warm seawater, individuals who have open wounds or exposure of soft tissue can contract an infection from direct contact with seawater. It is attributed to causing various illnesses in those who consume seafood or who have any open wounds that are exposed to sea water. While V. vulnificus rarely causes illness, it is profoundly underreported. Between 1988 and 2006, the Center for Diseases Control and Prevention (CDC) received over 900 reports of infections in the Gulf Coast states, the area such infections are primarily reported in. Prior to 2007, there the CDC did not have any coherent national surveillance system for maladies caused by the flesh-eating bacteria. In 2007, the CDC collaborated with the Gulf Coast states—Texas, Florida, Alabama, Mississippi, and Louisiana—to implement a monitoring system in various cases of the V. vulnificus infection in that region, thereby becoming a nationally recognized infection (CDC, 2013). An acute illness that causes rapid human health degradation, V. vulnificus infections do not cause long-term damage to human health after recovery. Although rare, medical personnel have an obligation to educate their patients on the dangers of exposing open wounds to saltwater and of ingesting raw seafood, especially oysters and shellfish.

Background

The first pathogen linked to V. vulnificus was isolated in 1976 after several blood culture samples were given to the CDC in its Atlanta office (Hollis et al., 1976). CDC officials pinpoint the etiological agent as bacteria that are “gram-negative bacteria” that naturally occurs in estuaries and other marine environments. It was given the name Vibrio vulnificus in 1979.  Decreasing salinity levels and increasing temperatures during certain seasons spawn a higher concentration of the bacteria in shellfish along the Gulf of Mexico and the Atlantic seaboard, especially in oysters. Microbiologists have constantly shown that there is a large presence of V. vulnificus in the guts of shellfish and oysters as well as in fish populations that inhabit oyster reefs. V. vulnificus causes sepsis in the majority of people—predominately me–who ingest raw oysters. Public health officials have identified strains of bacterial infections associated with V. vulnificus among displaced peoples from New Orleans in the aftermath of the flooding caused by Hurricane Katrina (Gold, 2005). According to the CDC (2013), on average there are fifty cases confirmed by culture samples, forty-five hospitalizations, and sixteen fatalities each year that are reported from the Gulf Coast states. At the national level, there have been reported as many as ninety-five cases—fifty percent of which have been confirmed by cultures—eighty five hospitalizations, and thirty five fatalities (CDC, 2013). Reported infections caused by V. vulnificus are seasonal, as over eighty percent of the infections take place between the months of May and October. Ecological factors such as salinity levels and water temperature elevate the amount of this pathogen in shellfish (CDC, 2013).  Total mortality rates for those who ingest it and those who contract it via open wound penetrated is approximately thirty three percent. Statistics show that this pathogen disproportionately affects men, although causal relations have yet to be established. Nonetheless, 85% of persons who experience endotoxic, septic shock are male. Women who have undergone an oopherectomy have increased mortality rates because this procedure causes a drop in estrogen levels. Researchers have found that the hormone estrogen has a protective impact on pathogenic infections caused by this bacteria (Merkel et al., 2001).

In 2015, meteorologists asserted that there have been eight reported cases of infection caused by V. vulnificus in six different counties (CDC, 2013). Two of the causes proved fatal in two counties in Florida, which is attributed to the fact that Florida experienced warm months, and the pathogen is more highly concentrated in brackish water in the littoral waters along the Gulf Coast region. With two fatalities out of eight reported incidents, the mortality rate is 25% within that localized outbreak, which is much more elevated than the mortality rate of other pathogens. Microbiologists have explained that the mortality rate of those infected by V. vulnificus depends on whether or not patients experience sepsis as a result of the infection. Septic shock thus causes fatalities, especially for those who have compromised immune systems and are infected.

Current Surveillance Methods

Since 1988, surveillance for V. vulnificus infections is concentrated in the Gulf Coast states and has expanded to include identified “FoodNet sites in 1996” (CDC, 2013). At the beginning of 2007, all infections caused by this pathogens—along with other Vibrio spp.–became notifiable at the national level. Since then, thirty-three states have administered such reporting to the CDC and public health officials at the state level (CDC, 2013). In 2003, California took a proactive approach to abating infection rates and reducing health risks by restricting the sale of shellfish and raw oysters that were harvested during the warmer months in the Gulf Coast region because of reports of elevated bacteria rates (Chesire, 2014). CDC and public health officials reported in 2013 that the California mandate correlated with the abatement of illness infections and deaths (CDC, 2013).

Epidemiological Analysis

Healthy people who consume Vibrio vulnificus experience abdominal pain, vomiting, and diarrhea. For individuals who have compromised immune systems, particularly those who suffer from chronic liver disease, ingesting Vibrio vulnificus can cause severe and life-threatening maladies if the bloodstream gets infected. Such illnesses include decreased blood pressure, septic shock, fever and chills, and blistering skin lesions. When the bloodstream gets infected by Vibrio vulnificus, fatalities occur in over 50% of those cases. If wounds are exposed to seawater, V. vulnificus often causes a noticeable breakdown of the skin as well as ulceration. A recent study conducted by the CDC demonstrated that individuals afflicted by pre-existing medical conditions are 80 times more likely to have their bloodstream infected by V. vulnificus than healthy individuals who are exposed to the bacteria. There is no evidence that suggests that the bacterial infection can be transmitted from person-to-person contact (CDC, 2013).  The production of toxins is pertinent to the pathogenicity of Vibrio vulnificus infections, which is why the pathogen is characterized as extremely virulent.

Every year, an estimated 48 million people fall ill as a result of food-borne illnesses and disease in the United States. In approximately 9.4% of these cases, experts can identify a specific pathogen that causes the illness, and over 90% of such cases have been causes by fifteen identified pathogens. Food-born diseases such as Vibrio vulnificus have yielded economic burdens, which are correlated to the incidence of thee illness (Hoffman et al., 2015). Estimates for the economic burden ranges on an idiosyncratic basis per case, but Vibrio vulnificus is estimated to cost $3.3 million per year in Florida (Hoffman et al., 2015). The financial costs are so high because of deaths that this disease causes in addition to hospitalizations. Indeed, Vibrio vulnificus is one of five pathogens that causes 94% of the total economic burden from pathogens that cause food-borne diseases.

The incidences of Vibrio vulnificus has only been reported in the Gulf States, especially in Florida waters where most of the cases have been reported.

Screening And Diagnosis

The V. vulnificus infections can be diagnosed by blood, stool, or wound cultures. If this infection is suspected, individuals are encouraged to notify a laboratory because a “special growth medium” should be utilized in order to hike the “diagnostic yield” (CDC, 2013). If patients present with fever, septic shock, low blood pressure and/or a gastrointestinal malady after ingesting raw seafood or if they report exposing open wounds to seawater, physicians should suspect the presence of this pathogen (CDC, 2013). Open wound sites are characterized by redness, swelling, and pain once infected and often have blisters that are tinged with blood. If suspected, physicians must administer antibiotics to their patients immediately in order to enhance their chances of survival. Doctors should pay particular attention to site of open wounds because in some cases the amputation of an infected limb is needed to save the patient’s life.

Clinical trials have hitherto not been conducted regarding how to manage infections cased by V. vulnificus, yet there are several recommended antibiotics touted by infectious disease experts and public health officials based on various animal models and case reports. Hemorrhagic bullae, or a culture of an open wound, is highly recommended and should be sent to a public health laboratory. Infectious disease experts recommend blood cultures if the patient presents with signs of sepsis; is febrile; and/or presents with hemorrhagic bullae. For antibiotic therapy, infectious disease experts recommend 100 mg of doxycycline twice a day for one-two weeks in addition to a third-generation cephalosporin taken every eight hours; or a “single agent regimen” containing fluoroquinolone such as ciproflaxacin, gatifloxacin, or levofloxacin, which has been successful in various animal models (CDC, 2913). Necrotic tissues must be debrided (removing necrotic tissue or dead skin cells), and the more severe cases often require limb amputation or fasciotomy (CDC, 2013).

Plan Of Action

In order to abate incidents of V. vulnificus infections and associated health consequences, the safety of oysters and other popular seafood items ingested raw must be vastly improved. Legally, oysters can only be harvested from waters that do not contain fecal matter, but even oysters that are legally harvested can become contaminated by the pathogen because of its natural presence in marine ecosystems (CDC, 2013). Unfortunately, V. vulnificus does not change the odor, appearance, or taste of oysters. Medical personnel must be vigilant in suspected cases, and they must voluntarily report infections to the CDC as well as to the regional Food and Drug Administration (FDA) offices in a collaborative effort to enhance the investigation of V. vulnificus infections. FDA specialists with knowledge about raw seafood help infection disease officials at the state level with “tracebacks of shellfish” (CDC, 2013). Once notified about  a case, regional FDA specialists must sample seawaters in order to ascertain any and all sources of infection and to close oyster beds if pathogenic problems are pinpointed. Medical personnel, CDC, and FDA officials must continue to research how to better predict environmental factors that amplify the likelihood that oysters and shellfish carry pathogens (CDC, 2013).

Medical personnel members are charged with responsibility to educate their patients on the various risks linked to ingesting raw or undercooked shellfish, particularly during the warmer months throughout the year. Refrigeration must be implemented from the time shellfish and oysters are harvested from sea beds to the time of consumption (CDC, 2013). In addition, medical personnel must report V. vulnificus infections in a timely manner.  Standards deployed for the determination of the opening and closing of oyster beds must be revised with special attention paid to various ecological factors. Outcomes will be measured by the reduction of reported infection rates and lower fatalities on an annual basis. A strategic communication and education plan must be implemented in order to mitigate health hazards associated with V. vulnificus infections, especially for consumers who ingest raw shellfish and oysters on a frequent basis and who are considered at-risk

Conclusion

Often called a summertime bacteria, Vibrio vulnificus infections are predominately reported between the months of May and October because warm weather causes an increase in salinity levels and weather temperatures. Persons who have compromised immune systems or suffer from liver disease are at higher risk of contracted an infection by this pathogen. In serious cases, infections can cause death via septic shock or require the amputation of a limb. In more milder cases, infected persons experience nausea, vomiting, abdominal pain, and diarrhea. Incident rates are relatively low, but the mortality rate is alarming in comparison to other pathogenic infections. Many individuals living in the Gulf Coast states enjoy consuming raw shellfish and oysters. Those afflicted by liver disease are also not aware of the various hazards correlated with the consumption of raw oysters or the exposure of open wounds and soft tissue to warm saltwater. Physicians, nurses, and other medical personnel must educate their patients, especially those suffering from liver disease or who have compromised immune systems, about the dangers linked to the consumption of raw or undercooked seafood or exposing their wounds directly to seawater. Receiving treatment in a timely manner is critical for recovery and to increase survival rates. While infections are rare, it is nonetheless critical for people to take precautions by not contacting seawater if they have open wounds or exposed soft tissue. Thoroughly cooking oysters and shellfish, wearing gloves when handling those foods, and discarding any oysters and shellfish that do not open once cooked are necessary preventative measures.

References

Centers for Disease Control and Prevention. (2013). Vibrio illness. CDC. Retrieved September 26, 2015 from http://www.cdc.gov/vibrio/vibriov.html

Chesire, S. (2014). Vibrio vulnificus: A summertime bacteria. Cnn. Retrieved September 26, 2015 from http://www.cnn.com/2014/08/07/health/vibrio-vulnificus-bacteria/

Gulf & South Atlantic Fisheries Foundation, Inc. (N.d.). Vibrio vulnificus illness reduction strategies and implementation program for the at-risk oyster consumer. Gulf & Atlantic Fisheries Foundation, Inc. Retrieved September 26, 2015      from http://www.issc.org/client_resources/strategic%20plan.pdf

Hoffman, S., MaCulloch, B., & Batz, M. (2015). Economic burden of manjor foodborne illnesses acquired in the United States. United States Department of Agriculture. Retrieved October 9, 2015 from www.ers.usda.gov/media/1837791/eib140.pdf

James, W.D. & Berger, T.G. (2006). Andrews’ diseases of the skin: Clinical dermatology. Saunders Elsevier.

Merkel, S.M., Alexander, S., Zufall, E., Oliver, J.D., & Huet-Hudson, Y.M. (2001). Essential role for estrogen in protection against vibro vulnificus-induced endotoxic shock. Infection and Immunity, 69 (10): 6119–6122.

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