This course will be updated or discontinued on or before Friday, October 2, 2026
Nationally Accredited
CEUFast, Inc. is accredited as a provider of nursing continuing professional development by the American Nurses Credentialing Center's Commission on Accreditation. ANCC Provider number #P0274.
Outcomes
≥ 92% of participants will know the presentation, management, and prevention of dengue fever to comply with the emergency order put in place by the Puerto Rico Department of Health.
Objectives
After completing this continuing education course, the participant will be able to meet the following objectives:
Assess the current state of emergency regarding dengue fever.
Summarize the dengue virus (including its subtypes).
Outline the transmission of dengue virus by mosquitoes.
Describe the symptoms that indicate dengue fever.
Identify relevant medical history and diagnostics to confirm dengue fever.
Explain treatment options for dengue fever.
Compare preventative measures that can be taken to prevent dengue fever.
CEUFast Inc. and the course planners for this educational activity do not have any relevant financial relationship(s) to disclose with ineligible companies whose primary business is producing, marketing, selling, re-selling, or distributing healthcare products used by or on patients.
Last Updated:
$39 Unlimited Access for 1 Year (Includes all state required Nursing CEs)
No Tests Required (Accepted by most states & professions)
Nursing Assistants from California, only. You must read the material on this page before you can take the test. The California Department of Public Health, Training Program Review Unit has determined that is the only way to prove that you actually spent the time to read the course. Less
Globally, dengue fever is an increasingly common vector-borne disease. It has recently become so prevalent that the government of Puerto Rico issued a state of emergency and new guidance for the detection, prevention, and treatment of Dengue Fever.
Transmitted by mosquitoes, the dengue virus can cause both mild and severe infections, and treatment is mainly supportive. Though symptoms are vague and nonspecific, several targeted and definitive diagnostic tests exist. Since treatment is supportive and cases can be severe, prevention at both the community and healthcare level is key to reducing the spread of dengue.
There are five well-known mosquito-borne diseases: dengue, Zika virus, malaria, chikungunya, and West Nile Virus. In addition, two separate mosquito species serve as vectors for these infections (Centers for Disease Control and Prevention [CDC], 2024d). Typically, these infections are endemic to tropical regions, and the incidence of cases increases with wet, rainy weather, which provides a better breeding ground for mosquitoes. Transmission typically occurs between the vector (mosquito) and the temporary host (human or non-human primate), and the risk of human-to-human transmission is low, except in certain cases (Schaefer et al., 2024).
Dengue virus, a single-stranded ribonucleic acid (RNA) virus belonging to the genus Flavivirus, has four subtypes (DENV-1, DENV-2, DENV-3, and DENV-4). Of the five mosquito-borne viruses mentioned above, dengue is the most common and has become endemic in some areas; however, epidemics frequently occur throughout the world, including in North and South America (Schaefer et al., 2024).
As dengue becomes endemic and people travel to these regions, the infection risk continues to increase, as does the risk of spreading dengue fever to non-endemic areas. The increased rainfall in Puerto Rico led the government to issue a state of emergency declaration to prevent further transmission of dengue fever (World Health Organization [WHO], 2024). In fact, at the time of the emergency declaration, the caseload had already increased by 231% when compared to the same timeframe in 2023 (Government of Puerto Rico, 2024).
With the localized spread of dengue fever in tropical and subtropical regions and continued travel to these locations, it is critical to prevent the infection of travelers and the global spread of the virus. While the virus is typically not fatal, it can lead to mortality if the appropriate supportive care is not received in a timely manner (Schaefer et al., 2024).
The symptoms of dengue fever can be mild or severe. While the mildest symptoms can be managed at home, this may lead to missed work, decreased economic productivity, and underestimated case counts(WHO, 2024). In more severe cases, when medical care is required, the healthcare system may be burdened, especially in areas with increased spread (Wong et al., 2022). As dengue fever continues to spread around the world via international travel, this will become a bigger issue. Both large-scale community modifications and personal preventative measures are critical to slowing the spread of dengue (WHO, 2024).
Dengue virus belongs to the genus of single-stranded RNA viruses known as Flavivirus and is the most commonly transmitted of the arboviruses or insect-borne diseases (Khan et al., 2023; Schaefer et al., 2024; Wong et al., 2022). Currently, it is most prevalent in tropical and subtropical regions because this climate zone is the most conducive to mosquito breeding. However, with increased international travel, global climate change, and other weather pattern changes, mosquitos are becoming more populous in previously uninhabited regions such as Europe. Each year, about 400 million people are infected with the dengue virus, and that number continues to grow (CDC, 2024a).
Known also as "dandy fever" (Kularatne & Dalugama, 2022), "breakbone fever," or "7-day fever", these monikers give an indication of both the symptoms experienced and the typical length of infection (Schaefer et al., 2024). The virus has four different serotypes, and unfortunately, immunity to one serotype does not extend to the other three, making it possible to be infected multiple times. The ability to contract multiple serotypes is also the reason why vaccination cannot occur without a lab-confirmed history of dengue infection.
Mosquitoes transmit several tropical diseases, including dengue fever. There are two specific species known to carry the dengue virus: Aedes aegypti and Aedes albopticus(Khan et al., 2023; Schaefer et al., 2024). Historically, Aedes aegypti transmitted more cases; however, as the geographic distribution of Aedes albopticus continues to spread (and these mosquitoes are known to be tolerant to cooler temperatures), higher case numbers may be seen. Also, in areas with sporadic and not endemic cases, the return of travelers carrying the dengue virus may increase the number of cases in a region if mosquitoes are around and can carry and transmit the virus (Wong et al., 2022). These mosquitoes are more active during the day, so active prevention on an individual level is important (Johns Hopkins Medicine, 2024).
The transmission process is fairly straightforward. Initially, the mosquito bites an infected human, who may be asymptomatic (WHO, 2024). The virus then multiplies in the mosquito's gut. The next time the mosquito bites a human, the virus is transferred to the human. In almost all cases, transmission occurs strictly between mosquitoes and humans. Very rarely, dengue can be passed between humans in the case of pregnancy when it is passed from parent to child via the placental blood flow or at delivery (Cleveland Clinic, 2022).
Due to the transmission process, herd immunity can develop over time unless there is a lot of travel into a community, as people and mosquitoes are infected by each serotype (Kularatne & Dalugama, 2022). However, the same circumstances that create herd immunity can lead to hyperendemicity as multiple strains circulate simultaneously (Schaefer et al., 2024). In this case, children and older adults are affected in higher proportions, and there is an increased risk of developing a severe presentation mediated by antibody-dependent enhancement (Cleveland Clinic, 2022; Scitable, n.d.).
Many individuals are completely asymptomatic, which is why pre-vaccine testing is so critical (Mayo Clinic, 2024). Generally, symptoms usually begin about four days to two weeks after being bitten, with an average incubation period of four to ten days, lasting anywhere from two to seven days (CDC, 2024a). In the 25% of individuals who do show symptoms, they can be both vague and nonspecific (Wong et al., 2022). They can include (CDC, 2024a):
High fever (104 degrees Fahrenheit/40 degrees Celcius)
Severe headache
Pain behind the eyes
Joint and muscle pain
Rash (appears blanching and macular within two days of the fever onset)
Nausea and vomiting
Leukopenia
Swollen lymph nodes
The definition of a probable case is fever plus two of the other symptoms in the context of recent travel to a dengue-endemic area (Kularatne & Dalugama, 2022).
There are two severe forms of dengue fever. These include dengue hemorrhagic fever (DHF) and dengue shock syndrome (DSS). Both forms are mediated by cellular and vascular level changes. In severe cases, the vasculature becomes leaky, and plasma starts to seep out into the extravascular space, leading to shock, clotting disorders, organ failure, and possibly death (Mayo Clinic, 2024; Wong et al., 2022). Typically, severe cases present with the second, third, or fourth infection with a different serotype. Antibody-dependent enhancement plays a key role in this pathology because the antibodies generated by the previous infection bind to the new viral particles. However, instead of neutralizing the virus, they cause a more effective binding of the entire antibody/viral complex to the monocytes, causing easier viral replication and more severe symptoms (Cleveland Clinic, 2022; Scitable, n.d.).
There are key differences between DHF and DSS.
DHF is characterized by (Kularatne & Dalugama, 2022):
Third-spacing into the:
Peritoneum
Pleural cavity
Other tissues
Increased cytokine production (cytokine storm)
DSS includes equally severe symptoms, such as (Kularatne & Dalugama, 2022):
Flushing (with blanching when pressure is applied to the skin)
Petechiae
Purpura
Bruising
Hepatomegaly
Tender right upper abdominal area
Increased liver function tests (demonstrated by a transaminitis > 1,000 international units [IU]/liter [L])
Decreased platelets and white blood cells
Increased hematocrit
In both cases, vascular leakage typically resolves in a day or two. However, as the fluid begins to resorb, and blood counts and liver enzymes start to normalize, pruritus may develop, as well as temporary bradycardia and increased urination.
Severe symptoms can appear in every body system, including the following (Kularatne & Dalugama, 2022):
Nervous system (encephalopathy, Guillain-Barre syndrome)
Gastrointestinal system (hepatitis, pancreatitis)
Renal system (nephritis)
Cardiac system (myocarditis or pericarditis)
Musculoskeletal system (myositis)
Hematological system (immune thrombocytopenic purpura)
Cases of severe myocarditis and hepatic necrosis are the leading causes of death (Kularatne & Dalugama, 2022).
Severe cases are more likely to occur in infants, pregnant people, and those over 65 with pre-existing medical conditions. Usually, a severe case will develop within one to two days after the fever's resolution. About 20% of infected people will develop a severe infection (Cleveland Clinic, 2022). There are several warning signs that the condition may become severe. These include the following (Mayo Clinic, 2024):
Abdominal pain/tenderness
Persistent vomiting
Ascites
Nose or other mucosal bleeding
Lethargy
Agitation
Hepatomegaly
Labored or fast breathing
Decreased platelet count
If a severe case is not treated promptly and appropriately, the fatality rate is about one percent. Dengue during pregnancy can cause miscarriage, low birth weight, or preterm delivery (Cleveland Clinic, 2022).
Dengue fever is more commonly diagnosed in children and young adults (Wong et al., 2022). However, it can occur at any age and in almost any geographic location. A diagnosis is made based on both clinical evaluation and laboratory testing.
In any individual presenting with a high fever, there should be a high suspicion of dengue, especially if they visited a known endemic/epidemic area (CDC, 2024d). The medical history should include a timeline and detailed history of their recent travels and any symptoms. If the geographic and physical history supports a possible dengue infection, several laboratory tests could be ordered to make a confirmatory diagnosis.
The initial diagnostic test to be done is a polymerase chain reaction (PCR) test, otherwise known as a nucleic acid amplification test (NAAT). This blood test is the gold standard for detecting viral deoxyribonucleic acid (DNA) and should be done within the first seven days of symptom development (CDC, 2024d; Wong et al., 2022).
The dengue nonstructural protein 1 (NS1) antigen test is also done using a blood sample collected within the first seven days of symptoms. It detects the specific dengue antigens that trigger the immune system to generate antibodies; this can serve as a confirmatory test for the NAAT (Wong et al., 2022).
There are also tests that can be done after the initial symptoms or if the NAAT is negative. The dengue immunoglobulin M (IgM) and immunoglobulin G (IgG) antibody tests can suggest (but do not confirm 100%) that a person has had a recent dengue infection. There is a possibility that antibodies will be found due to infection for cross-reactive viruses like the Zika virus (Wong et al., 2022). In that case, there is another test, the plaque reduction neutralization test (PRNT), which can differentiate between dengue and other Flaviviruses. This is not always possible, as it is not widely available and it takes a long time to generate results; therefore, this test is not used as frequently as the others (Wong et al., 2022).
Treatment consists of both general supportive care and symptom management for severe cases. Supportive care for mild cases includes adequate hydration, fever reduction, and pain management; this may include the use of Tylenol (non-steroidal anti-inflammatory drugs like aspirin and ibuprofen should not be given due to an increased risk of hemorrhage). Cool cloths or baths can also help with the fever and discomfort (Wong et al., 2022).
In severe cases, hospitalization will be necessary. During the hospitalization, intravenous fluids should be initiated as soon as warning signs are noted; this will maintain the intravascular volume by using isotonic solutions. The overall goal is to maintain the appropriate volume but minimize the risk of fluid overload (Wong et al., 2022). Vital signs and laboratory values (including those related to hydration status) require frequent monitoring. Changes in blood counts or liver function, which are the two most common lab abnormalities, may require more intensive care. Blood and platelet transfusions can be beneficial but are not widely used (Schaefer et al., 2024). In some studies, platelet transfusions have not been shown to provide benefit, nor have steroids or immunosuppressants (Wong et al., 2022). To provide general help, the CDC has a hotline for clinicians to call for a consultation about dengue fever and patient care (Schaefer et al., 2024).
Since dengue fever can be severe and even fatal, prevention is key. Mosquito control and public health measures are the two most important areas on which to focus prevention efforts.
Mosquito bites should be prevented in all individuals, including those who have been previously vaccinated (Wong et al., 2022). In addition, personal and environmental steps can be taken to prevent mosquito population growth and biting. These include the following items.
To eliminate a mosquito's breeding site, receptacles should be emptied regularly of all standing water (Cleveland Clinic, 2022; Wong et al., 2022). In cases where this may not be possible, such as in standing bodies of water, fish and small freshwater crustaceans can be added to the environment to consume the mosquitoes (Schaefer et al., 2024).
Using insect repellent, which targets mosquitoes, is important to prevent bites. This could include 20-30 percent DEET (Cleveland Clinic, 2022), IR3535, or picaridin (Schaefer et al., 2024). In addition, some clothes are sprayed with permethrin which is another form of repellent (Johns Hopkins Medicine, 2024).
Nets can be especially useful in cases where windows or doors cannot be kept closed, such as in hot climates where there is no air conditioning (Cleveland Clinic, 2022). Similarly, holes in window and door screens should be repaired immediately (Wong et al., 2022).
Public health measures are equally as important as mosquito control. These include community clean-ups, which help to reduce the mosquito population, mosquito control and surveillance, and vaccination.
Many factors provide good conditions for mosquito population growth. These include the following (Wong et al., 2022):
Standing water
Poor living conditions
Increased movement into urban areas
Trash accumulation
No air conditioning
High humidity
High temperatures
Increased rainfall
While addressing the actual physical community needs, community members' attitudes need to be assessed and adjusted to ensure that they realize the methods by which dengue is spread (i.e., storing water, not using mosquito repellents or screens) and the steps that can be taken to minimize the risks (WHO, 2024).
There are a couple of methods to control mosquito populations on a bigger scale. Genetically modified mosquitoes, which cannot spread the virus, can be introduced into the environment to compete with native mosquitoes (Wong et al., 2022). Another tactic is to introduce the bacteria Wolbachia pipientis into the mosquito's gut. This can cause fertilized eggs to be non-viable and make infected mosquitoes less capable of transmitting arboviral diseases, such as dengue (Khan et al., 2023).
Vaccination has been recommended by the Advisory Committee on Immunization Practices (ACIP) since 2021 for all children ages nine to sixteen in endemic areas (Wong et al., 2022). However, before a vaccination can be given, the child must have a confirmed history of dengue infection. This is because receiving a vaccine without a previous infection increases the risk of a severe presentation with any future infections, which is related to antibody-dependent enhancement (Wong et al., 2022).
Dengvaxia (from Sanofi) was the first dengue vaccine used in the United States and one of the first vaccines requiring laboratory testing before administration. This vaccine is a three-dose series, with each given six months apart (Wong et al., 2022). It is reputed to be 80% effective against symptomatic dengue, and one can expect to experience typical vaccine side effects (headache, injection site pain, and/or myalgia) after receiving it. Due to low demand, Sanofi has stopped manufacturing the vaccine (CDC, 2024b; CDC, 2024c).
A 32-year-old male presented to an emergency room with a high fever (duration of eight days), bilateral hemorrhages in the eyes, swollen lips and hands, and a bleeding nose. At the time of presentation, he did not have any bleeding from other mucosal surfaces and voiced that he did not have any significant family or personal medical history. He also stated that he was married, came from a middle-class background, and denied any substance abuse or other risky behaviors (Mushtaque et al., 2020).
Intervention/strategies:
This patient was living in Pakistan at the time of emergency room presentation. He had a high-grade fever, bilateral ocular hemorrhaging, limited edema, and bleeding from a mucus membrane. Dengue virus is endemic to Pakistan, making this part of the differential diagnosis. In addition, other common tropical diseases such as malaria, leptospirosis, and viral hepatitis were considered.
Upon assessment, his vitals were normal with the exception of temperature. He was jaundiced and displayed mild edema of the lower extremities and hands. His complete blood count (CBC) showed multiple changes in platelets, white blood cells, and hemoglobin. Liver function tests were steeply elevated, as were coagulation labs (activated partial thromboplastin time [APTT] and international normalized ratio [INR]). A urine culture grew Candida, and a chest/abdomen computed tomography (CT) scan showed bilateral pleural effusions, ascites, and hepatomegaly. He was given fluids, Tylenol, antiemetics, antibiotics, and antifungals (Mushtaque et al., 2020).
Discussion of outcomes:
He was determined to have dengue fever (via a positive NS1 assay) and subsequently developed a systemic yeast infection. Later on, he developed hepatitis E and a noticeable hematoma of the iliopsoas muscles, causing him lower extremity pain and decreased mobility. He was treated with antibiotics and antifungals, making a full recovery for discharge (Mushtaque et al., 2020).
Strengths and weaknesses:
This case study presented a fairly straightforward case in which dengue fever was almost immediately part of the differential diagnosis. Testing quickly confirmed the diagnosis, and appropriate treatment was started for his complicating hepatitis and Candida symptoms.
If he had been traveling, or dengue was not necessarily endemic to Pakistan, it may have taken longer to arrive at a diagnosis. In the interim, the hepatitis E and yeast infection may have complicated his case and made treatment more difficult or confusing.
Dengue fever is a mosquito-borne illness endemic to much of the tropical and subtropical world. However, as the climate continues to warm and mosquitoes migrate further north, the risk increases that dengue fever will become more prevalent. Symptoms are generally vague and nonspecific in mild cases but may turn into DHF or DSS, especially in second, third, or fourth infections with different serotypes. Diagnosis can be done through several different tests, although the PCR/NAAT test is the gold standard. Since vaccination is not widely available and can only be given after a confirmed infection, prevention is the key to minimizing the spread of dengue virus. Through the use of community-level measures and better mosquito control and surveillance, the frequency with which dengue is transmitted should hopefully decrease.
Select one of the following methods to complete this course.
Take TestPass an exam testing your knowledge of the course material.
OR
No TestAttest that you have read and learned all the course materials.
Implicit Bias Statement
CEUFast, Inc. is committed to furthering diversity, equity, and inclusion (DEI). While reflecting on this course content, CEUFast, Inc. would like you to consider your individual perspective and question your own biases. Remember, implicit bias is a form of bias that impacts our practice as healthcare professionals. Implicit bias occurs when we have automatic prejudices, judgments, and/or a general attitude towards a person or a group of people based on associated stereotypes we have formed over time. These automatic thoughts occur without our conscious knowledge and without our intentional desire to discriminate. The concern with implicit bias is that this can impact our actions and decisions with our workplace leadership, colleagues, and even our patients. While it is our universal goal to treat everyone equally, our implicit biases can influence our interactions, assessments, communication, prioritization, and decision-making concerning patients, which can ultimately adversely impact health outcomes. It is important to keep this in mind in order to intentionally work to self-identify our own risk areas where our implicit biases might influence our behaviors. Together, we can cease perpetuating stereotypes and remind each other to remain mindful to help avoid reacting according to biases that are contrary to our conscious beliefs and values.
Centers for Disease Control and Prevention (CDC). (2024a). About Dengue. Centers for Disease Control and Prevention. Visit Source.
Centers for Disease Control and Prevention (CDC). (2024b). Dengue Vaccine. Centers for Disease Control and Prevention. Visit Source.
Centers for Disease Control and Prevention (CDC). (2024c). Increased Risk of Dengue Virus Infections in the United States. Centers for Disease Control and Prevention. Visit Source.
Centers for Disease Control and Prevention (CDC). (2024d). Mosquito-Borne Diseases in Workers. National Institute for Occupational Safety and Health (NIOSH). Visit Source.
Khan, M. B., Yang, Z. S., Lin, C. Y., Hsu, M. C., Urbina, A. N., Assavalapsakul, W., Wang, W. H., Chen, Y. H., & Wang, S. F. (2023). Dengue overview: An updated systemic review. Journal of infection and public health, 16(10), 1625–1642. Visit Source.
Kularatne, S. A., & Dalugama, C. (2022). Dengue infection: Global importance, immunopathology and management. Clinical medicine (London, England), 22(1), 9–13. Visit Source.
Mayo Clinic. (2024). Dengue Fever. Mayo Clinic. Visit Source.
Mushtaque, R. S., Ahmad, S. M., Mushtaque, R., & Baloch, S. (2020). A Curious Case of Dengue Fever: A Case Report of Unorthodox Manifestations. Case reports in medicine, 2020, 1701082. Visit Source.
Schaefer, T. J., Panda, P. K., & Wolford, R. W. (2024). Dengue Fever. In: StatPearls [Internet]. StatPearls Publishing. Visit Source.
Scitable. (n.d.). Model of antibody-dependent enhancement of dengue infection. Nature Education. Visit Source.
Wong, J. M., Adams, L. E., Durbin, A. P., Muñoz-Jordán, J. L., Poehling, K. A., Sánchez-González, L. M., Volkman, H. R., & Paz-Bailey, G. (2022). Dengue: A Growing Problem With New Interventions. Pediatrics, 149(6), e2021055522. Visit Source.
World Health Organization (WHO). (2024). Dengue and severe dengue. World Health Organization. Visit Source.
We're sorry! All our support agents are unavailable to chat at the moment.
Need Immediate Assistance? Please visit our FAQ section which provides answers to many common inquiries.
Get in Touch Directly via Email If your query is urgent or you'd prefer to reach us directly, we invite you to submit a support ticket through our Contact Us page. Our dedicated support team will review your inquiry and get back to you as soon as possible.
Support Hours Our chat support is typically available Monday to Friday, 9:00 AM - 6:00 PM EST. For support outside of these hours, please use our email contact
Are you sure?
You should NOT select "Remember me for 30 days" if you are on a public or shared computer.
