Answer:

The information circulating on social media claiming that every 1°C increase in temperature leads to a 10% increased risk of stroke is inaccurate. While it's true that hot weather can contribute to stroke risk by causing dehydration and electrolyte imbalances, leading to thicker blood and increased strain on the heart, this does not translate to a direct 10% increase. These conditions can promote blood clots, which can cause strokes. Additionally, fluctuating blood pressure due to temperature changes can also elevate the risk of stroke or recurrence. However, there is currently no research confirming the claimed 10% increase in stroke risk.

Stroke is a consequence of multiple factors, including stress, age, smoking, substance use, a sedentary lifestyle, and pre-existing conditions such as high blood pressure, heart disease, diabetes, and prior strokes. Certain infectious diseases like influenza, shingles, and pneumococcal pneumonia can also increase stroke risk.

Rising temperatures are also linked to an increased risk of dengue fever. A meta-analysis of studies from 1990-2022, published in The Lancet (2023), found that a 1°C temperature increase correlated with a 7-13% higher risk of dengue fever. This is because the Aedes aegypti mosquito, the vector for dengue fever, thrives in warm temperatures. Higher temperatures facilitate mosquito breeding, accelerate their development, and extend their lifespan.

Hot weather in Hanoi. Photo: Giang Huy

During hot weather, people tend to go outside in the early morning and late afternoon, which coincide with peak mosquito biting times, increasing the risk of dengue transmission. High temperatures also encourage cities and provinces to plant more trees for shade, which can inadvertently provide ideal breeding grounds for Aedes aegypti mosquitoes.

At 37 years old, the best preventative measure is to consider vaccination against preventable diseases like dengue fever, influenza, pneumococcal disease, and chickenpox. The dengue fever vaccine is recommended for children aged 4 and above, as well as adults. The vaccination schedule consists of two doses, three months apart, with an efficacy rate of over 80% in preventing the disease and over 90% in preventing hospitalization. Women are advised to receive the vaccine at least one month, ideally three months, before pregnancy.

The influenza vaccine is administered annually, while there are various pneumococcal vaccines available, including one covering 24 common pneumococcal bacteria strains. Adults are advised to receive combined vaccinations for optimal protection. The chickenpox vaccine for adults involves two doses administered one month apart.

In addition to vaccination, adopting a healthy lifestyle that includes a balanced diet, adequate sleep, avoiding alcohol and tobacco, regular exercise, and managing underlying health conditions can help prevent strokes.

Dr. Nguyen Tien Dao

Medical Manager, VNVC Vaccination System

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