Public Health Ministry warns of rising disease risks during rainy season, urges preventive measures

The Department of Disease Control (DDC) on Tuesday held a press briefing on the “Health and Safety During the Rainy Season”.

Dr Jurai Wongsawat, spokeswoman for the DDC, warned of increased risks of eight diseases during the rainy season, including COVID-19, influenza, dengue fever, and measles. She urged the public to take precautions, especially in light of the rising cases of COVID-19 and the threat of bird flu, which has recently emerged in Cambodia.

1. COVID-19

As of 2025, Thailand has reported 545,560 cases and 206 deaths from COVID-19. The majority of deaths were among individuals over 60 years of age, with 93% of those falling into the 608 group. A recent surge in COVID-19 clusters has been observed, particularly in educational institutions.

The Department of Medical Sciences reported that NB.1.8.1 is the dominant strain, with XEC and JN.1 strains in decline. The World Health Organization (WHO) has designated NB.1.8.1 as a variant of concern due to several mutations in the spike protein, though there is no evidence yet of increased severity.

2. Influenza

From January 1 to June 26, 382,471 cases of influenza have been reported, with 51 deaths. The highest mortality rates were among individuals with underlying conditions, including kidney disease, heart disease, diabetes, and high blood pressure. The flu has been most common in children aged 5–9 years, followed by 0–4 years and 10–14 years.

There have been 48 influenza outbreaks in schools, and while flu cases are on the decline, they are still higher than in 2024.

Prevention Tips for Acute Respiratory Infections:

• Wear a mask in crowded places.
• Wash your hands frequently with soap or alcohol-based gel.
• If you have flu-like symptoms, rest and avoid contact with others until recovered.
• People in high-risk groups should get the flu vaccine annually, available free of charge at government and participating private hospitals from May to August 2025.

3. Dengue Fever

In 2025, Thailand has reported 19,491 cases of dengue fever and 21 deaths, a 1.8-fold decrease from last year. However, there has been an increase in cases across the country, particularly in the North and South. The majority of cases are in school-age children, with the highest death rate in those over 45 years old.

Residents are advised to use mosquito repellent, wear protective clothing, and sleep in mosquito nets if staying in rural or forested areas. If experiencing high fever for 1-2 days, taking fever-reducing medicine is recommended. Seek medical help immediately if symptoms persist or worsen.

4. HIV

As of 2025, Thailand has reported 547,556 people living with HIV, with 454,552 currently undergoing antiretroviral treatment. The country also recorded 4,712 deaths related to HIV. New diagnoses of HIV for the year 2025 reached 10,931, showing a downward trend since 2017. Most new cases were found in the 25-49 year age group, with 1 in 5 new diagnoses occurring among young people aged 15–24. The five provinces with the highest number of new HIV cases are Bangkok, Chonburi, Nakhon Ratchasima, Khon Kaen, and Udon Thani. Of the new cases, 96.4% were HIV infections resulting from unprotected sexual contact.

5. Syphilis

The number of syphilis cases has risen significantly, with 25,469 reported in 2024, compared to 8,737 in 2022—a 2.9-fold increase. The 15-24 age group saw a 2.5-fold increase in cases from 3,672 in 2022 to 9,359 in 2024. Congenital syphilis cases have also seen a drastic rise, with 1,290 cases in 2024—a 5.4-fold increase from 240 in 2022, mostly affecting mothers under 25 years of age. The increase in syphilis cases is often linked to delayed or missed prenatal care, with many women failing to seek antenatal services before 12 weeks of pregnancy.

Health Recommendations:

• Always use condoms during sexual activity with all partners and through all sexual practices.
• If at risk, regularly get tested for HIV and sexually transmitted infections (STIs).
• Start treatment immediately if diagnosed, to reduce the risk of complications and prevent the transmission of infections to sexual partners.

6. Leptospirosis (Rat Fever)

From January 1 to June 26, Thailand reported 1,623 cases of Leptospirosis, with 20 deaths. There has been a slight increase in cases, particularly among individuals aged 60 and above. The primary risk factors include walking through flooded areas or muddy ground without protective footwear, improper food storage, and fishing in contaminated water.

Health Recommendations for Leptospirosis:

• Avoid wading through mud or standing in water for long periods. Wear rubber boots and gloves if necessary.
• After wading or being in the water, wash hands, feet, and body with soap and clean water immediately.
• If experiencing high fever, headache, muscle pain, or fatigue after exposure to contaminated water, seek medical attention immediately and inform the doctor about the exposure.

7. Avian Influenza (Bird Flu)

As of 1 January 2003 to 27 May 2025, there have been 976 confirmed cases of H5N1 avian influenza worldwide, with 470 deaths. In Thailand, the risk remains low, but continuous surveillance is still necessary. In Cambodia, 9 cases were reported in 2025, with 6 fatalities. The most recent case, reported on 24 June 2025, involved a resident of Siem Reap who had contact with a dead chicken of unknown cause and later developed fever, coughing, and breathing difficulties. The patient is currently in a critical condition.

In the United States, from 2024 to 2025, there have been 70 reported cases, with 1 death.

Prevention Tips for the Public:

• Consume properly cooked food, especially poultry, eggs, and dairy products.
• Avoid contact with sick or dead poultry, pigs, or cattle.
• Wear a mask, gloves, and wash hands frequently after contact with animals.
• Poultry, pig, and cattle farmers should report any cases of sick or dead poultry to veterinary authorities immediately.

If you experience flu-like symptoms, such as fever, coughing, runny nose, difficulty breathing, or red, inflamed eyes, seek medical attention immediately. For those travelling to areas with avian influenza outbreaks, it is important to follow updates and ensure appropriate health insurance. If returning from abroad with flu-like symptoms, visit a doctor immediately and inform them of any animal contact or travel history.

8. Measles

From January 1 to June 23, 1,295 cases of measles or suspected German measles were reported. Of these, 425 cases were confirmed as measles, with 371 confirmed and 54 epidemiologically linked. The majority of cases were in children under 5 years old.

The highest number of cases were reported in the four southern border provinces: Narathiwat, Pattani, Yala, and Songkhla, though the trend appears to be declining. Over the past 6 weeks, cases have been increasing in areas outside the southern border provinces, notably in Rayong, Sa Kaeo, Chonburi, Chanthaburi, Prachuap Khiri Khan, and sporadically in Trat, Surin, Ratchaburi, Phuket, Phetchaburi, and Phang Nga.

Prevention Tips for Measles:

• Isolate suspected measles patients to prevent the spread of the disease.
• The most important prevention measure is the MMR vaccine (measles, mumps, and rubella), which should be administered during childhood, with first dose at 9-12 months of age, and second dose at 1 year and 6 months.