Is it Dengue or is it COVID-19?

What You Need to Know

During the COVID-19 pandemic, healthcare providers in areas where dengue is endemic or who are treating patients with recent travel history to these areas, need to consider dengue and COVID-19 in the differential diagnosis of acute febrile illnesses.
Most people with dengue and COVID-19 have mild illness and can recover at home; symptoms usually last a few days, and people tend to feel better after a week.
However, both dengue and COVID-19 can cause severe illness that can result in death.
The clinical management for people who develop severe illness with either of these two diseases is quite different, often requiring hospital-based care.
Anyone of any age can develop severe illness with dengue or COVID-19. Both infections are more likely to cause complications in adults with underlying chronic conditions, such as diabetes and heart disease.
- Dengue: Risk factors for severe illness [PDF – 1 page]
- COVID-19: People at higher risk for severe illness
Healthcare providers should perform appropriate tests (for dengue; for COVID-19) and follow the patient closely for warning signs.
- Dengue warning signs include persistent vomiting, mucosal bleeding, difficulty breathing, lethargy/restlessness, postural hypotension, liver enlargement and progressive increase in hematocrit.
- COVID-19 warning signs include difficulty breathing, persistent pain or pressure in the chest, new confusion, inability to wake or stay awake, bluish lips or face. This list is not all possible symptoms.
Complications for both dengue and COVID-19 can develop before test results come back. Clinical management should be guided by clinical presentation.

Dengue and COVID-19 symptoms
Dengue	COVID-19
Transmission
Dengue, an illness caused by any of 4 dengue viruses, is mainly transmitted to people through the bites of infected Aedes species mosquitoes (primarily Ae. aegypti or Ae. albopictus species).	COVID-19, a respiratory illness caused by the virus SARS-CoV-2, is mainly transmitted from person to person through respiratory droplets that are spread when an infected person coughs, sneezes, or talks.
Incubation Period
The incubation period for dengue ranges between 3-10 days, typically 5-7 days.	The incubation period for COVID-19 is thought to extend to 14 days, with a median of 4-5 days from exposure to symptoms onset.
Clinical Course The clinical manifestations of both dengue and COVID-19 can range from mild to critical.
Signs and Symptoms
Mild to moderate disease Febrile phase Fever Headache with eye pain Myalgia Nausea Vomiting Rash Leukopenia Warning signs for severe illness: abdominal pain or tenderness, persistent vomiting, clinical fluid accumulation, mucosal bleeding, lethargy, restlessness, and liver enlargement. Critical Phase Warning signs may appear, and rapid clinical deterioration may occur within 48 hours after defervescence (3–7 days after fever onset).	Mild to moderate disease Fever or chills Cough Shortness of breath or difficulty breathing Fatigue Muscle or body aches Headache New loss of taste or smell Sore throat Congestion or runny nose Nausea or vomiting Diarrhea NOTE: These signs and symptoms of COVID-19 are the ones most persons with the illness have experienced. However, this list is not inclusive.
Severe Illness
Severe dengue is defined by dengue with any of the following symptoms and signs: Plasma leakage leading to shock Fluid accumulation with respiratory distress Severe bleeding with thrombocytopenia Severe organ impairment such as liver disease with elevated transaminases, or meningoencephalitis with impaired consciousness Heart impairment	Among patients who developed severe disease, the medium time to dyspnea ranged from 5 to 8 days, the median time to acute respiratory distress syndrome (ARDS) ranged from 8 to 12 days, and the median time to ICU admission ranged from 10 to 12 days. Signs and symptoms for severe illness can include: dyspnea hypoxia respiratory failure shock multiorgan system dysfunction Clinicians should be aware of the potential for some patients to rapidly deteriorate one week after illness onset. See: Interim Guidelines for Management of Patients with Confirmed Coronavirus Disease (COVID-19) Children: CDC and partners are also investigating reports of multisystem inflammatory syndrome in children (MIS-C) associated with COVID-19
Risk Factors for Severe Illness
Risk factors for severe dengue include: Age (infant) Second dengue infection In most dengue-endemic countries, children and young adults are at highest risk for a second infection Patients with chronic medical conditions, including diabetes, asthma, or heart disease	Risks factors for severe illness with COVID-19 include: Age >65 Underlying conditions like cardiovascular disease, diabetes, chronic respiratory disease, hypertension, prior stroke, liver disease, obesity, chronic lung disease, chronic kidney disease undergoing dialysis, or immunocompromise (e.g., poorly controlled HIV, undergoing cancer treatment, using corticosteroids, smoking) People who live in a nursing home or long-term care facility