Recognizing and Managing Emerging Infectious Diseases in the Emergency Department

Points

For the safety of healthcare workers and the general public, a detailed travel history, vaccination status, and risk exposures should be obtained from all ED patients who present with signs and symptoms of viral infection, including fever, rash, muscle pain, and/or respiratory illness.

Consult the CDC Travelers' Health site for the latest updates on emerging and re-emerging infections. For other relevant websites, see Table 3.

Middle East Respiratory Syndrome

• Middle East respiratory syndrome (MERS) is caused by an RNA virus and is spread via camel saliva, milk, or meat. Human-to-human transmission occurs via droplets or fomites.
• Up to one-third of new infections are nosocomial.
• After an incubation period of 5 to 12 days, patients typically present with fever, cough, shortness of breath, vomiting, and diarrhea.
• Testing is done by RT-PCR, ELISA, or immunofluorescence assay and should be done in conjunction with the Department of Health.
• Treatment is largely supportive. Vaccines are in development using antibodies from MERS survivors.

Chikungunya Infection

• Chikungunya infection is caused by an RNA virus that is spread via mosquito bites or by vertical transmission.
• After an incubation period of 3 to 7 days, patients classically present with fever and symmetric distal arthritis. Other nonspecific infectious findings include headache, vomiting, diarrhea, rash, and fatigue.
• Dengue and malaria can present similarly to chikungunya, so these infections should be ruled out.
• Common lab abnormalities include elevated liver function tests, lymphopenia, hypocalcemia, and (rarely) thrombocytopenia.
• Testing is done by RT-PCR, ELISA, or immunofluorescence assay and should be done in conjunction with the Department of Health.
• Treatment is with pain control. Steroid therapy with referral to a rheumatologist for long-term management of joint pain may be required.

Zika Infection

• Zika infection is caused by an RNA virus that is spread via mosquito bite, blood transfusion, sexual intercourse, or vertical transmission.
• After an incubation period of 2 to 7 days, patients commonly present with fever, rash, headache, conjunctivitis, arthralgias, and myalgias.
• Zika can be diagnosed clinically, but if confirmation is needed, send RT-PCR or IgM serology, and discuss with the Department of Health.
• Treatment is supportive, with acetaminophen until dengue has been ruled out. NSAIDs can be administered after the patient has been afebrile for 48 hours.

• When considering any emerging infection, consider ordering dengue titers and malaria peripheral smears to rule out these infections early in the course of acute illness.
• Neonates born to mothers with a high chikungunya viral load are at risk of severe neurologic or cardiac complications and even death.
• Ensure that your ED has a protocol in place to evaluate patients concerning for emerging infections and for follow-up of results that return after the patient has been discharged.

Table 3. Traveler Health Websites

Access more tables and figures here

Clinical Pathway for Management of Suspected Middle East Respiratory Syndrome

Clinical Pathway for Management of Suspected Chikungunya Virus Infection

Clinical Pathway for Management of Suspected Zika Virus Infection

Access the Clinical Pathway here

Most Important References

• Rivers CM, Majumder MS, Lofgren ET. Risks of death and severe disease in patients with Middle East respiratory syndrome coronavirus, 2012-2015. Am J Epidemiol. 2016;184(6):460-464. (Retrospective; 1291 cases) DOI: https://doi.org/10.1093/aje/kww013
• Alhamlan FS, Majumder MS, Brownstein JS, et al. Case characteristics among Middle East respiratory syndrome coronavirus outbreak and non-outbreak cases in Saudi Arabia from 2012 to 2015. BMJ Open. 2017;7(1):e011865. (Cohort; 1273 cases) DOI: https://doi.org/10.1136/bmjopen-2016-011865
• Weaver SC, Lecuit M. Chikungunya virus and the global spread of a mosquito-borne disease. N Engl J Med. 2015;372(13):1231-1239. (Systematic review) DOI: https://doi.org/10.1056/NEJMra1406035
• Staikowsky F, Talarmin F, Grivard P, et al. Prospective study of chikungunya virus acute infection in the island of La Reunion during the 2005-2006 outbreak. PLoS One. 2009;4(10):e7603. (Prospective; 274 cases) DOI: https://doi.org/10.1371/journal.pone.0007603
• Araujo AQ, Silva MT, Araujo AP. Zika virus-associated neurological disorders: a review. Brain. 2016;139(Pt 8):2122-2130. (Review) DOI: https://doi.org/10.1093/brain/aww158
• Beckham JD, Pastula DM, Massey A, et al. Zika virus as an emerging global pathogen: neurological complications of Zika virus. JAMA Neurol. 2016;73(7):875-879. (Review) DOI: https://doi.org/10.1001/jamaneurol.2016.0800
• Musso D, Gubler DJ. Zika virus. Clin Microbiol Rev. 2016;29(3):487-524. (Review) DOI: https://doi.org/10.1128/CMR.00072-15
• Calvet GA, Santos FB, Sequeira PC. Zika virus infection: epidemiology, clinical manifestations and diagnosis. Curr Opin Infect Dis. 2016;29(5):459-466. (Review) DOI: https://doi.org/10.1097/QCO.0000000000000301
• Wang JZ, Guo XH, Xu DG. Anatomical, animal, and cellular evidence for Zika-induced pathogenesis of fetal microcephaly. Brain Dev. 2016;39(4):294-297. (Review) DOI: https://doi.org/10.1016/j.braindev.2016.10.012
• Staples JE, Breiman RF, Powers AM. Chikungunya fever: an epidemiological review of a re-emerging infectious disease. Clin Infect Dis. 2009;49(6):942-948. (Epidemiological review) DOI: https://doi.org/10.1086/605496
• Goupil BA, Mores CN. A review of chikungunya virus-induced arthralgia: clinical manifestations, therapeutics, and pathogenesis. Open Rheumatol J. 2016;10:129-140. (Clinical review) http://europepmc.org/abstract/med/28077980