Bugging the system: West Nile virus - Editorial

AORN Journal, Feb, 2004 by Nancy J. Girard

Preventing the devastating effects of microorganisms on patients and health care workers is a major goal of perioperative nurses. The increasing incidence and migration around the world of viruses, such as the West Nile virus (WNV), require continuing updates and potential modifications to perioperative care. These microorganisms are spreading faster than science can keep up with them, bugging not only the human system, but the health care delivery system as well.

The impact of these virulent agents was made clear to my family recently. A family member suddenly became ill with unusual symptoms that mimicked several neurological disorders. Pain, weakness, severe headaches, increasing numbness, and weakness in her legs and arms, along with mental changes, led to a scary hospitalization. After a week of diagnostic testing, the results came back. She had WNV and, consequently, earned a number as a Texas victim of WNV. Luckily, despite the severity of neurological symptoms, she recovered completely within three months. Her health care provider communicates with her frequently, sharing the newest Centers for Disease Control and Prevention (CDC) updates about the disease.

As my family members and I gained knowledge about WNV, it became clear that the disease could have ramifications in the OR. For example, my family member's neurologist told her that she could never donate blood again because the virus can be contracted via a blood transfusion. She also could never donate an organ. Another piece of information was that she should never get a flu shot. Unfortunately, this was after she had gotten the flu shot, so she did have a minor relapse.

WHAT IS WNV?

Most people tie the appearance of WNV in the United States to New York in 1999. A number of dead birds were found in New York City that year, and a relationship was established between the birds and an increased incidence of encephalitis and meningitis in humans. (1) The causative culprit was identified as a flavivirus. Other flaviviruses are yellow fever, Japanese encephalitis, dengue, and Saint Louis encephalitis. The cycle of transmission for WNV is infection of a bird, which is bitten by a mosquito that then bites human and other hosts, such as horses, to transmit the virus. (2)

West Nile virus has spread rapidly across the nation in just four years. Statistics from the CDC through December 2003 show a total of 8,734 diagnosed cases in 2003, and 208 of the infected patients died. (3) Cases have shown up in almost every state, but a few states have the majority of WNV cases, including Colorado (2,477 cases with 45 deaths), Nebraska (1,760 cases with 21 deaths), and South Dakota (1,013 cases with 21 deaths). Although Texas has had only 586 diagnosed cases, it has the largest ratio of deaths at 32. (3) General recommendations for prevention from the CDC are to minimize potential exposure to mosquitoes, use repellent containing N,N-diethyl-3-methylbenzamide (ie, DEET), and report any incidence of dead birds.

Links to individual state and local government WNV web sites can be found at http://www.cdc.gov/ncidod/dvbid/westnile/city_states.htm. The World Reference Center for Arboviruses, which is located at the University of Texas medical branch at Galveston and is maintained by the National Institution for Allergies and Infectious Diseases, is researching better diagnostic procedures, information about the virus and how it is transmitted, and new vaccines and antiviral medicines. (2)

SYMPTOMS

Symptoms of WNV are described as none, mild, or serious. The majority of people infected with the virus have a mild case and exhibit no symptoms at all; thus, researchers cannot determine exactly how many people are infected. Some patients develop a mild case of WNV and have symptoms similar to those of flu (ie, fever; headache; nausea and vomiting; body aches; swollen lymph glands; skin rash on chest, stomach, and back that lasts several days). Serious cases of WNV occur in about one in 150 people who contract the virus. These people can have encephalitis, meningitis, high fever, severe headache, stupor, disorientation, muscle weakness, vision disturbances, numbness in limbs, paralysis that can be permanent, or they may die. Diagnosis can be complicated because WNV mimics neurological disorders, such as multiple sclerosis or Guillian Barre. (4) For my family member, these serious symptoms proved confusing to medical staff members. This was the first case seen at that hospital, and diagnosis was delayed because WNV was not suspected.

IMPLICATIONS FOR PERIOPERATIVE NURSES

There are implications concerning WNV for perioperative nurses. Perioperative nurses need to be knowledgeable about the disease. Asking about a positive diagnosis of WNV in preoperative data collection can alert health care professionals to potential problems in patients who have had WNV. These patients may be more susceptible to postoperative viral infections. People older than 50 years of age are at the highest risk for developing significant symptoms and may develop encephalomyelitis.