Flu, virus or dengue: learn how to identify each disease

Recently (19) the city of São Paulo declared a state of public emergency for dengue fever. In addition, seasonal diseases, such as flu and viruses, have been circulating with increasing frequency due to climate change. In this scenario, it is essential to understand exactly what the condition is in order to provide more targeted and effective treatment.

Dengue fever, for example, has some medications that are contraindicated because they can worsen the disease or cause complications. Anti-inflammatories, corticosteroids, paracetamol and antibiotics are some examples that should be avoided. In addition, there are levels of the disease, some may feel it more intensely than others, with different guidelines.

With symptoms that may seem similar, such as fever, headache and body aches, distinguishing between flu, virus and dengue can be challenging. However, each of these diseases has specific signs that help in diagnosis, as explained by infectious disease specialist Igor Thiago Queiroz, member of the Brazilian Society of Infectious Diseases.

According to Queiroz, the main difference lies in the respiratory symptoms. "Dengue, unlike the flu and other common viruses, does not usually cause a runny nose, coughing or sneezing," he explains. The flu is usually accompanied by a sore throat, nasal congestion and, in some cases, shortness of breath. Gastrointestinal viruses — such as norovirus and rotavirus — tend to cause nausea, vomiting and diarrhea.

Another important point is to identify the warning signs. "If there is severe abdominal pain, persistent vomiting, dizziness when standing up or cold hands, this may indicate that dengue is progressing to a more serious condition," says the specialist. He emphasizes that, if you notice these symptoms, it is essential to seek medical attention immediately.

Dengue fever can be diagnosed clinically, considering the symptoms and the epidemiological situation of the region, but confirmation comes through laboratory tests. "In the first week, the NS1 antigen or RT-PCR detect the genetic material of the virus. IGM serology can confirm the infection seven days after the onset of symptoms," explains Queiroz.

For any of these diseases, basic treatment includes rest, constant hydration and symptomatic medications, such as analgesics (Dipyrone or Paracetamol). However, Queiroz warns: "In dengue, anti-inflammatories and corticosteroids are contraindicated, as they increase the risk of bleeding."

Prevention also follows different paths. For dengue, it is essential to eliminate breeding sites for Aedes aegypti, use repellents and clothing that covers the skin, in addition to vaccination available for adolescents aged 10 to 14 through the SUS. For flu and respiratory viruses, the recommendation includes the use of masks, hand hygiene and keeping distance from sick people.

When faced with non-specific symptoms, the infectious disease specialist's advice is clear: "Rest, stay hydrated and, if you notice signs of worsening, seek medical help. Correct diagnosis is essential to avoid complications."