Early Symptoms of Ebola Virus Warned as a Dangerous Infectious Disease with High Fatality Rate

Get to know "Ebola virus" Early symptoms resemble other infectious diseases. It is warned as a dangerous infectious disease with a high fatality rate, along with prevention advice.

From the outbreak of the "Ebola" virus in the Democratic Republic of Congo and Uganda, the outbreak has intensified. Data from the Department of Disease Control reveals a World Health Organization report suspecting over 900 infected cases and 220 deaths. This outbreak is caused by the Bundibugyo strain as of 26 May 2026 GMT+7.

Subsequently, Thailand's Communicable Disease Board escalated measures to control "Ebola" from travelers arriving from two countries, "Democratic Republic of Congo and Uganda." Upon entering Thailand, travelers must quarantine for 21 days even if asymptomatic.

Understanding the Ebola virus (Ebolavirus)

Ebola disease The world first recognized this virus in 1976 when it was found near the Ebola River in the Republic of Congo. Outbreaks have occurred sporadically since then. The average fatality rate is 50%, but it can reach up to 90% among infected individuals.

According to the World Health Organization (WHO), there are six Ebola virus strains. Three are known to cause severe outbreaks:

• Ebola virus (EBOV), which causes Ebola virus disease (EVD).
• Sudan virus (SUDV), which causes Sudan virus disease (SVD).
• Bundibugyo virus (BDBV), which causes Bundibugyo virus disease (BVD).

The "Ebola virus" naturally resides in fruit bats and spreads to humans through infected wild animals such as monkeys. Human-to-human transmission occurs through

1. Direct contact with broken skin or mucous membranes with blood, bodily fluids such as saliva, vomit, feces, urine, sweat, or semen from patients or deceased individuals.

2. Contact with contaminated objects or surfaces with infected blood or bodily fluids such as vomit or feces from patients or the deceased.

Incubation period and transmission of Ebola

• The incubation period is 2–21 days.
• Patients begin to be contagious once symptoms appear.
• Deceased patients can still transmit the virus through direct contact with their bodies.

Symptoms of Ebola disease

• Early symptoms include high fever, fatigue, and muscle pain, followed by vomiting, diarrhea, abdominal pain, and rash.
• Severe cases may have abnormal bleeding, low blood pressure, confusion, behavioral changes, and multi-organ failure such as liver and kidney failure. Because the symptoms resemble other infectious syndromes like dengue fever, malaria, and typhoid fever,

diagnosis requires a risk history of travel to outbreak countries and compatible symptoms, confirmed by laboratory tests such as viral genetic material detection (PCR), immunological testing, or virus culture.

Ebola disease treatment

• Specific antiviral treatment with monoclonal antibodies like mAb114 (ansuvimab™) or REGN-EB3 (Inmazeb™) is recommended only for Ebola virus disease. Other strains currently have no specific antiviral treatment.
• Supportive care includes fluid replacement, correction of electrolyte imbalances, treatment of low blood sugar, shock management, and antibiotics for secondary infections to prevent complications.

Ebola disease prevention

1. Avoid traveling to countries with Ebola virus outbreaks.

2. Avoid contact with individuals who are ill or deceased from Ebola disease.

3. Current vaccines are approved only for the Ebola virus strain (Ebola virus).

Other strains, including Bundibugyo virus, do not have approved vaccines yet.

Currently, there are no reported Ebola virus cases in Thailand, but travelers returning from high-risk countries are advised to follow government guidance for proper symptom monitoring. Infections may also be introduced by travelers who are asymptomatic carriers.

Since Ebola has a high fatality rate, early diagnosis can improve survival chances. If experiencing high fever, fatigue, muscle pain, or headache, seek medical attention promptly and provide travel history within 21 days before symptom onset.

Reference: Dr. Puangrat Tangthitikul, specialist in respiratory and critical care medicine, Department of Internal Medicine, Nawavej Hospital.