Air, heat and dengue in Ho Chi Minh City

Short answer: the everyday health risks in Saigon are mosquitoes, fine-particle haze, heat and dodgy water, and a few habits handle most of them.

The short version

Dengue is the big one. Ho Chi Minh City recorded more than 25,000 cases in the first eight months of 2025, over three times the same period in 2024 [3]. There's no malaria in the city itself [2].
PM2.5 pollution regularly climbs into the "unhealthy" range, especially at morning and midday peaks. Check an air quality app daily and run a purifier at home [1].
Don't drink the tap water or trust ice of unknown origin [2].
Heat, humidity and the wet season shape your days. Plan exercise early, drink more than you think and expect afternoon downpours and flooded streets.
See a GP or travel clinic in Australia six to eight weeks before you leave. For long stays the CDC recommends hepatitis A, typhoid, hepatitis B and Japanese encephalitis, and rabies for some people [2].

Dengue: the mosquito that bites in daylight

If you've lived in Cairns or Townsville you may know dengue. Most Australians haven't met it. In Saigon it's part of life.

Dengue is endemic in Vietnam. Transmission peaks in the rainy season but happens all year [2]. In 2025 Ho Chi Minh City had a bad year: the city's Center for Disease Control (HCDC) counted 25,578 cases to late August, more than three times the roughly 8,000 at the same point in 2024, with 15 deaths. It also identified 286 new dengue clusters across 88 wards and communes in a single week [3].

The mosquito that carries it, Aedes, bites mostly in the early morning and late afternoon, not at night like the ones that bother you at a barbecue [4]. It breeds in small pools of still water: pot-plant saucers, buckets, blocked gutters, old tyres.

How to protect yourself

Use repellent with DEET, picaridin or oil of lemon eucalyptus. Put sunscreen on first, then repellent [4].
Cover up in light, loose clothing when you're outdoors at dawn and dusk [4].
Fix your home. Screens on windows, a bed net for kids, and an aircon room you can close up [4].
Tip out water every few days: plant saucers, pet bowls, balcony drains. Tell your housekeeper why.
Ask building management about fogging. Many condos spray common areas during outbreaks.

When to see a doctor

Sudden high fever, a bad headache, pain behind the eyes, muscle and joint aches or a rash should send you to a doctor, not the pharmacy. Avoid ibuprofen and aspirin until dengue is ruled out, as they increase bleeding risk; paracetamol is the usual choice. Warning signs such as severe stomach pain, persistent vomiting or bleeding gums need a hospital the same day.

The Hospital for Tropical Diseases in Cho Quan ward is the city's specialist centre, and all the international hospitals treat dengue too [6]. See our guide to hospitals and health insurance in Ho Chi Minh City for how payment works.

What about a vaccine?

Smartraveller's dengue advice, last updated in May 2024, says there's no vaccine to prevent a first dengue infection, and that the one it mentions is only for people meeting specific conditions [4]. Vaccine options have been changing, so ask your GP or travel doctor what's currently suitable for you before you go.

Air pollution: watch the PM2.5, not the sky

Hanoi gets the headlines, but Saigon's air is a problem too. The CDC notes high particulate pollution in both cities, enough to worsen asthma and raise the risk of respiratory infections [2].

On 13 December 2025, Ho Chi Minh City ranked among the world's ten most polluted cities on IQAir, with an AQI of 179 ("unhealthy") at 10 am and PM2.5 around four times the WHO guideline. By evening it had dropped to "moderate" [1]. That swing is typical: traffic, construction, household and industrial emissions build up through the morning [1].

AQI reading	Category	What we'd do
0–50	Good	Get outside, run, ride, open the windows
51–100	Moderate	Fine for most people. Sensitive people take it easy
101–150	Unhealthy for sensitive groups	Kids, older people, asthmatics move exercise indoors
151–200	Unhealthy	Mask outdoors, purifier on, windows shut
201+	Very unhealthy or worse	Stay in where you can, skip outdoor exercise

Categories follow the US AQI scale used by IQAir.

Practical air habits

Check an air quality app. IQAir's AirVisual is what most expats use, and city authorities advise checking hourly updates [1].
Wear a proper mask on the bike. A well-fitted, high-quality particulate mask helps when you're out for long periods, not a cloth fashion mask [1][2].
Run a HEPA purifier in bedrooms, sized for the room. Replace filters on schedule; they clog fast here.
Exercise smart. Early morning before the traffic, or indoors on high-AQI days.
Asthmatics: bring your preventer and reliever inhalers, plus a spare [2].

Water, ice and street food

The CDC says tap water and ice aren't safe to drink in Vietnam [2]. Brushing your teeth with tap water is a personal call; most expats use filtered or bottled water.

Drinking water: big refillable bottles delivered to your apartment are standard and cheap. Or install a filter.
Ice: the cylindrical factory ice with a hole in the middle is generally made from treated water. Crushed ice from an unknown block is riskier.
Street food: one of the best things about Saigon. Pick busy stalls with high turnover, where food is cooked hot in front of you.
Skip raw blood dishes. Dishes made with uncooked pig blood carry risks of Streptococcus suis and trichinellosis. The CDC's advice: ask, and when in doubt, don't eat it [2].
Raw seafood and undercooked meat are worth a second thought, especially in the heat [2].

Heat, humidity and the wet season

Saigon is hot all year, and the humidity makes it feel hotter than the same temperature in Perth or Adelaide. The south has a dry season and a wet season. The rains usually run from around May to November, with short, heavy afternoon storms that flood streets in minutes.

Hydrate properly. Water plus electrolytes if you sweat a lot. Oral rehydration salts are sold in every pharmacy.
Move your outdoor time to early morning or evening.
Watch for heat exhaustion: headache, dizziness, nausea, heavy sweating. Get cool and drink; if confusion sets in, it's an emergency.
Floods bring their own risks. Don't wade through floodwater with cuts on your feet, and watch for open drains. More rain also means more breeding spots for mosquitoes.
Typhoon season brings storms, mainly to the centre and north, but Saigon gets heavy rain from them too. Follow local forecasts and the Smartraveller advice for Vietnam [5].

Vaccinations before and after you move

Book a GP or travel clinic in Australia six to eight weeks before you fly, so courses can be finished. Bring your records, because you'll want them in Saigon too.

Vaccine	Who it's for	Notes
Routine (measles, tetanus, flu, COVID)	Everyone	Make sure you're up to date
Hepatitis A	Most travellers	Recommended by the CDC [2]
Typhoid	Most travellers	Recommended by the CDC [2]
Hepatitis B	Long-term residents	Recommended for long stays [2]
Japanese encephalitis	Anyone staying a month or more	The CDC recommends it for all travellers spending at least a month in Vietnam [2]
Rabies (pre-exposure)	Outdoor types, animal lovers, young children	Rabid dogs cause almost all of Vietnam's rabies infections [2]

You can top up vaccines in Saigon at the international clinics or the Pasteur Institute vaccination centre, which also handles rabies shots [7]. If a dog or cat bites or scratches you, wash the wound for several minutes with soap and water and get post-exposure treatment the same day. It's widely available, though the immune globulin given in severe cases is harder to find [2].

Your first-month health checklist

Download an air quality app and set an alert.
Buy a purifier for the bedroom and a box of particulate masks.
Stock repellent, paracetamol and oral rehydration salts.
Organise water delivery or a filter.
Register with an international clinic and save its after-hours number.
Ask locals and other Australians what they wish they'd known. Join Cooee Vietnam, our Facebook group for Australians in Vietnam, where members swap purifier and clinic tips.

Air, heat and dengue: staying healthy in Ho Chi Minh City