Emerging Infectious Diseases

Emerging infectious diseases (EID) are a global threat to public health. It is imperative that emergency nurses understand the current infectious disease landscape, participate in timely information-sharing, and become familiar with the tools to contain and combat EIDs.

Emerging infectious diseases can be newly-recognized, like MERS, or well-known diseases breaking out in previously uninfected populations or geographic areas, such as the Chikungunya virus, which recently appeared in Florida.

The term “emerging” also refers to infectious diseases that are reappearing, as measles has just done in California, or that are changing, like the influenza virus does every year. Infections could also be caused by bacteria like MRSA (methicillin-resistant Staphylococcus aureus) that have become resistant to antibiotics, or drug-resistant tuberculosis. EIDs can also be zoonotic diseases such as Lyme disease, Salmonella, rabies, and even the plague, which naturally infect animals but can spread to humans.

ENA Position Statement: Emerging Infectious Diseases in the Emergency Care Setting



Zika Virus

zika_body_400Zika was first discovered in the Zika forest in Uganda in 1947. It is common in both Africa and Asia. The virus was first detected in the Western Hemisphere in May 2015 when an outbreak occurred in Brazil. Zika virus is a mosquito-borne flavivirus transmitted to people primarily through the bite of an infected mosquito of the Aedes genus. These mosquitoes are also responsible for spreading dengue and chikungunya viruses. Some evidence does suggest that Zika virus can be transmitted through blood transfusion, sexual transmission, and perinatal transmission.

The incubation period for Zika virus is typically between two and 12 days, and the disease itself is usually mild, with symptoms lasting only a few days. Signs and symptoms include low-grade fever frequently accompanied by a maculopapular rash.

Other common symptoms include muscle pain, joint pain with possible swelling, headache, pain behind the eyes, and conjunctivitis. Because symptoms are often mild, the infection may go unrecognized or be misdiagnosed. Prevention and control of this disease rely heavily on reducing the breeding of Aedes mosquitos and minimizing contact as well as using barriers such as insect repellents. There is currently no vaccine against the Zika virus, and treatment focuses on symptom management.

Ebola Virus

ebola_body_400Ebola, previously known as Ebola hemorrhagic fever, is a deadly disease caused by infection with one of the Ebola virus species. Ebola can cause disease in humans and nonhuman primates (monkeys, gorillas, and chimpanzees).
Ebola is caused by infection with a virus of the family Filoviridae, genus Ebolavirus. There are five identified Ebola virus species, four of which are known to cause disease in humans: Ebola virus (Zaire ebolavirus); Sudan virus (Sudan ebolavirus); Taï Forest virus (Taï Forest ebolavirus, formerly Côte d’Ivoire ebolavirus); and Bundibugyo virus (Bundibugyo ebolavirus). The fifth, Reston virus (Reston ebolavirus), has caused disease in nonhuman primates, but not in humans.

Ebola was first discovered in 1976 near the Ebola River in what is now the Democratic Republic of the Congo. The natural reservoir host of Ebola virus remains unknown. However, based on evidence and the nature of similar viruses, researchers believe that the virus is animal-borne and that bats are the most likely reservoir. Four of the five virus strains occur in an animal host native to Africa.

CDC Resources

About Ebola Virus Disease
Ebola outbreaks 2000-2017

Avian Influenza

Avian influenza viruses infect wild fowl like geese, ducks, and turkeys, sometimes without causing apparent signs of illness. The same viruses can spread to domestic poultry, leading to outbreaks of serious disease, and occasionally have caused infections in humans and other mammals. 

The ongoing spread of avian influenza H5N1 and H7N9 viruses in poultry, particularly in areas where the viruses are endemic in the wild bird population, is a continuing threat to public health. This is exacerbated by the tendency of all influenza viruses to mutate, which may change the range of species they can infect as well as the severity of the resulting disease. For these reasons, it is important to be aware of these types of virus and their infectious potential.

CDC Resources

About Avian Influenza
Background and Clinical Illness
Transmission of Avian Influenza A Viruses Between Animals and People


Measles is a highly contagious illness, especially in very young children and infants that have not been vaccinated. Emergency nurses may be the first to recognize the signs and symptoms in a patient and need to be prepared to keep themselves, patients, and the community safe from further exposure. ENA recommends that emergency nurses remain informed by reviewing information from recognized sources, such as those below.

CDC Resources

About Measles
Cases and Outbreaks
Information for Healthcare Providers

Middle East Respiratory Syndrome Coronavirus (MERS-CoV)

MERS (Middle East Respiratory Syndrome) is a newly emerging infectious disease caused by the MERS Coronavirus (MERS-CoV). First detected in Saudi Arabia in 2012, it has spread from the Arabian Peninsula to several other countries including the U.S. and South Korea.

The source of MERS is currently unknown, but researchers believe it is likely to have originated by transfer of the virus from an animal. Most people who become infected with MERS-CoV develop symptoms of severe acute respiratory illness, including fever, cough, and shortness of breath. Understanding how MERS spreads can help to prevent further cases.

CDC Resources

About MERS
MERS in the U.S.
Interim Guidance for Healthcare Professionals