10 Most Common Illnesses in Vietnam

Vietnam has a mixed health profile. Everyday infectious illnesses such as respiratory infections, gastrointestinal infections and dengue occur alongside chronic conditions including cardiovascular disease, diabetes and chronic respiratory disease. For residents and travellers, understanding this combination is more useful than thinking only about tropical diseases.

There is no single official ranking of the ten most frequently diagnosed illnesses across every age group and region of Vietnam. Disease patterns also change by season, location and population. The conditions below are therefore ten common or important illnesses and health problems in Vietnam, selected using information from the World Health Organization and other established health authorities rather than presented as a strict national prevalence ranking.

Some are especially relevant to travellers, while others account for a substantial share of illness and death among people living in Vietnam long term.

1. Respiratory infections

Respiratory infections are among the most familiar reasons people become unwell in Vietnam. They include viral upper respiratory infections, influenza and lower respiratory infections such as pneumonia.

Symptoms can include:

• Cough.
• Sore throat.
• Runny or blocked nose.
• Fever.
• Headache.
• Muscle aches.
• Fatigue.

Vietnam's climate, densely populated cities and year-round movement of respiratory viruses mean that these illnesses can occur throughout the year.

Most mild respiratory infections improve without hospital treatment, but medical assessment becomes more important if there is significant breathing difficulty, persistent high fever, chest pain, confusion, severe weakness or worsening symptoms.

WHO mortality data also show that lower respiratory infections remain an important cause of death in Vietnam, particularly when illness becomes severe or affects vulnerable patients.

2. Dengue fever

Dengue is one of the most important mosquito-borne diseases in Vietnam. It is transmitted primarily by infected Aedes mosquitoes, which are active during the daytime as well as around dawn and dusk.

WHO states that dengue occurs in Vietnam and historically tends to peak between June and October, although transmission can occur outside this period. Central and southern Vietnam have accounted for a large proportion of reported cases.

Typical symptoms may include:

• Sudden fever.
• Severe headache.
• Pain behind the eyes.
• Muscle and joint pain.
• Nausea or vomiting.
• Rash.

Most infections are mild or manageable with appropriate medical care, but severe dengue can develop. Warning signs can include persistent vomiting, severe abdominal pain, bleeding, rapid breathing, marked weakness or blood in vomit or stool.

Seek prompt medical care for suspected dengue, particularly if symptoms worsen as the fever begins to fall. WHO advises that people with warning signs of severe dengue require immediate assessment.

Do not assume that every fever in Vietnam is dengue. Influenza, respiratory infections and other illnesses can cause similar symptoms.

3. Gastroenteritis and travellers' diarrhoea

Diarrhoea, vomiting and other gastrointestinal illnesses are common health concerns for both residents and travellers. They can be caused by viruses, bacteria, parasites or contaminated food and water.

Symptoms may include:

• Loose or watery stools.
• Abdominal cramps.
• Nausea.
• Vomiting.
• Fever.
• Loss of appetite.

Many mild episodes improve with hydration and time. The main immediate concern is often dehydration, particularly in children, older adults and people who are vomiting repeatedly.

Seek medical care if you have blood in the stool, severe abdominal pain, persistent high fever, significant dehydration, repeated vomiting or symptoms that are worsening rather than improving.

Food safety remains useful even when living in Vietnam long term. Wash hands regularly, use safe drinking water and be cautious with food that has been stored or handled improperly.

4. Hand, foot and mouth disease

Hand, foot and mouth disease, or HFMD, is a common infectious illness in Vietnam, particularly among young children.

WHO reports that HFMD circulates throughout the year in most Vietnamese provinces, with typical peaks from March to May and September to December. Tens of thousands of cases have historically been reported each year, and large outbreaks can occur.

Common symptoms include:

• Fever.
• Painful sores in the mouth.
• Blisters or rash on the hands and feet.
• Rash around the buttocks.
• Reduced appetite.

Most cases are mild and resolve on their own, but some enteroviruses associated with HFMD can cause serious neurological, cardiovascular or respiratory complications.

Parents should seek medical advice if a child becomes unusually sleepy, develops breathing problems, has repeated vomiting, experiences seizures or deteriorates rapidly.

Good hand hygiene and cleaning frequently touched surfaces and children's toys can help reduce transmission.

5. Tuberculosis

Tuberculosis, or TB, remains an important infectious disease in Vietnam. It is caused by Mycobacterium tuberculosis and most commonly affects the lungs.

TB spreads through the air from people with active pulmonary disease. It is different from the brief exposure associated with many everyday viral infections, because transmission risk is generally greatest with prolonged or repeated close contact with someone who has untreated active pulmonary TB.

Possible symptoms include:

• Persistent cough.
• Coughing up sputum or blood.
• Chest pain.
• Unexplained weight loss.
• Fever.
• Night sweats.
• Persistent weakness or fatigue.

WHO identifies tuberculosis as a significant health issue in Vietnam. The disease is generally treatable with a combination of antibiotics, but treatment must be completed correctly because drug-resistant TB can be more difficult to manage.

A cough lasting several weeks, particularly with weight loss, fever or night sweats, warrants medical assessment.

6. Hepatitis B

Chronic hepatitis B is an important health issue in Vietnam and across the Western Pacific region.

Hepatitis B is a viral infection that affects the liver. It can be transmitted through infected blood and certain body fluids, as well as from mother to child around the time of birth.

Many people with chronic hepatitis B have no obvious symptoms for years, which means infection may be discovered only through blood testing.

When symptoms occur, they can include:

• Fatigue.
• Nausea.
• Abdominal discomfort.
• Dark urine.
• Yellowing of the skin or eyes.

Long-term infection can increase the risk of cirrhosis and liver cancer.

Vaccination is highly effective at preventing hepatitis B. People who are unsure of their vaccination or infection status can discuss testing and vaccination with a healthcare professional.

7. Hypertension and cardiovascular disease

The most important health problems in Vietnam are not limited to infectious disease. Noncommunicable diseases now account for around 80% of deaths in Vietnam, according to WHO's 2025 assessment.

Cardiovascular disease is particularly important. This broad category includes hypertension, coronary heart disease, heart attack and stroke.

High blood pressure often causes no obvious symptoms, which is why routine measurement matters. Long-term uncontrolled hypertension increases the risk of stroke, heart disease and kidney disease.

WHO data identify stroke as the leading cause of death in Vietnam, with ischaemic heart disease also among the leading causes.

Important risk factors include:

• Tobacco use.
• High salt intake.
• Physical inactivity.
• Unhealthy diet.
• Excessive alcohol consumption.
• Diabetes.
• High cholesterol.

Regular blood pressure checks are particularly useful for adults and people with cardiovascular risk factors.

Sudden facial drooping, weakness on one side of the body, difficulty speaking, severe chest pain or unexplained breathing difficulty should be treated as an emergency.

8. Diabetes

Diabetes is another major chronic health condition in Vietnam, particularly type 2 diabetes.

The condition develops when blood glucose remains too high because the body cannot produce enough insulin or use insulin effectively.

Possible symptoms include:

• Increased thirst.
• Frequent urination.
• Unexplained weight loss.
• Fatigue.
• Blurred vision.
• Slow-healing wounds.

However, type 2 diabetes can develop gradually and may cause few symptoms initially.

WHO data list diabetes among the leading causes of death in Vietnam. Long-term uncontrolled diabetes can contribute to cardiovascular disease, kidney damage, eye disease, nerve damage and foot complications.

People with risk factors such as obesity, family history, hypertension or previous abnormal blood glucose results can discuss appropriate screening with a healthcare professional.

9. Chronic obstructive pulmonary disease

Chronic obstructive pulmonary disease, usually abbreviated to COPD, is a long-term lung condition that causes persistent airflow limitation and breathing problems.

WHO identifies COPD as an important health burden in Vietnam, particularly among older adults and men.

Common symptoms include:

• Persistent cough.
• Mucus production.
• Shortness of breath.
• Wheezing.
• Reduced exercise tolerance.

Tobacco smoking is a major cause. Exposure to second-hand smoke, occupational dust and fumes, and indoor or outdoor air pollution can also contribute.

COPD is not the same as a temporary respiratory infection. Symptoms generally develop over a longer period and may progressively worsen.

People with a chronic cough or persistent breathlessness should seek medical evaluation rather than assuming the symptoms are simply caused by pollution or ageing.

10. Skin infections and fungal conditions

Skin problems are common in tropical environments, although there is no single national condition that represents all cases.

Vietnam's warm and humid climate can contribute to fungal infections, heat-related rashes and irritation, while cuts, insect bites and scratching can sometimes lead to bacterial skin infections.

Common problems encountered in tropical climates can include:

• Fungal infections of the feet or groin.
• Ringworm.
• Folliculitis.
• Infected insect bites.
• Minor bacterial skin infections.
• Heat rash.

Keep the affected area clean and dry where appropriate, and avoid sharing towels or personal items when a contagious fungal infection is suspected.

Seek medical assessment if redness spreads rapidly, significant swelling develops, there is pus or severe pain, fever occurs or a wound is not healing normally.

Are tropical diseases the biggest health risk in Vietnam?

Not necessarily.

Dengue and other infectious diseases are important, especially for travellers and during outbreaks, but Vietnam's overall disease burden has increasingly shifted toward chronic disease.

WHO reported in December 2025 that noncommunicable diseases account for about 80% of deaths in Vietnam. Cardiovascular disease, cancer, chronic respiratory disease and diabetes are therefore major public-health concerns alongside communicable illnesses.

This distinction matters because a visitor searching for common illnesses in Vietnam may be mainly concerned about dengue or food poisoning, while someone living in the country for many years should also consider routine screening, smoking exposure, blood pressure, diabetes risk and other long-term health issues.

Illness patterns vary across Vietnam

Health risks are not identical in Hanoi, Ho Chi Minh City, Da Nang or rural provinces.

Factors that can change disease patterns include:

• Season.
• Rainfall and mosquito activity.
• Urban or rural environment.
• Age.
• Vaccination status.
• Workplace exposures.
• Air quality.
• Recent travel.
• Existing medical conditions.

For example, dengue is particularly important in central and southern areas, while malaria risk is concentrated in specific rural areas and is not considered a transmission risk in major cities such as Hanoi, Ho Chi Minh City or Da Nang according to current CDC travel guidance.

That is why symptoms should be assessed in the context of where you have recently travelled rather than simply where you currently live.

When should you see a doctor?

Arrange medical assessment if symptoms are persistent, worsening or difficult to explain, particularly when there is significant fever, dehydration, prolonged cough, unexplained weight loss or breathing difficulty.

Seek immediate local medical help for severe breathing difficulty, chest pain, signs of stroke, loss of consciousness, seizures, uncontrolled bleeding, severe allergic reactions or another potentially life-threatening condition.

Vietnam's ambulance number is 115.

If you need care while travelling or living in the country, How to Choose an English-Speaking Clinic in Vietnam explains how to check language support and medical services. You can also read Sick in Vietnam? What to Do and Where to Go for practical guidance on choosing between a clinic, hospital and emergency department.

Frequently Asked Questions

The answers below address common questions about illness and disease patterns in Vietnam. They provide general health information and should not be used to diagnose symptoms without an appropriate medical assessment.

Conclusion

Vietnam's common health problems include both infectious diseases and long-term conditions. Respiratory and gastrointestinal illnesses, dengue, hand, foot and mouth disease, tuberculosis and hepatitis B remain relevant, while cardiovascular disease, diabetes and chronic respiratory disease represent a substantial part of the country's overall health burden.

For travellers, mosquito protection, food and water precautions, vaccination and knowing where to obtain medical care can reduce risk. For long-term residents, routine preventive care, blood pressure checks and appropriate screening are just as important as awareness of tropical infections.

Sources

1. World Health Organization Viet Nam Health Profile
2. World Health Organization Viet Nam: Noncommunicable Disease Action
3. World Health Organization Chronic Obstructive Pulmonary Disease in Viet Nam