Viruses in the raging weather: The extreme heatwave hitting the country during May 2026 brings with it not only unusual fluctuations and high temperatures, but also a bloom of seasonal viruses. Although the classic winter viruses are no longer with us, the healthcare system reports an increase in visits due to eye infections, intestinal infections and diverse respiratory diseases. The combination of heavy heat, prolonged stays in closed and air–conditioned spaces and extreme temperature changes assists the spread of these viruses among the population. These are the viruses currently active and what can be done to deal with them.
<br>Adenovirus
The "Adeno" virus family includes about 57 strains and a very wide range of diseases, depending on the different strains. Adenoviruses are very common during the winter and transition seasons, and they spread quickly, usually through saliva and nasal secretions. The virus is considered relatively resistant to environmental conditions, which allows it to survive on surfaces in kindergartens and public places.
What are the symptoms: The viruses usually cause infections in the respiratory tract, throat infections and lung tract infections, viral eye infection accompanied by redness and discharge, digestive tract infections causing diarrhea and vomiting, urinary tract infections, and in rarer cases also meningitis and encephalitis. Many parents report a high fever that lasts several days and is accompanied by significant exhaustion of the child.
Is there a vaccine: There is currently no vaccine or drug against the virus for use by the general public.
What is the treatment: The main medical treatment is based on supportive treatment for the accompanying symptoms, such as fever reduction and pain relief. It is important to ensure plenty of drinking to prevent dehydration, especially when digestive system symptoms appear.
Human metapneumovirus
This virus, known for short as HMPV, belongs to the paramyxovirus family and is a central cause of respiratory morbidity when the winter season ends. It affects people of all ages, but it is especially dangerous for infants, the elderly and people with a weakened immune system. The virus is transmitted through direct contact with secretions from the nose or mouth, or through the air via coughing and sneezing.
What are the symptoms: The virus causes a disease very similar to the flu or the RSV virus. Patients suffer from a runny nose, cough, shortness of breath and high fever. In more severe cases the virus may cause pneumonia or bronchiolitis, which is an infection of the small airways in the lungs. In asthma patients the virus may trigger severe attacks that require intensive drug treatment.
Is there a vaccine: As of today there is no approved vaccine against this virus.
What is the treatment: The treatment is mainly conservative and supportive. It includes rest, providing fluids to prevent dehydration and use of drugs for fever reduction. In cases where respiratory difficulty appears, there may be a need for oxygen administration or inhalation treatments within a hospitalization framework.
<br>Enterovirus and hand, foot and mouth disease
The Entero group of viruses includes the Coxsackie and Echovirus viruses, and they are very active in Israel starting from May and throughout the summer months. The most well–known disease caused by these viruses is hand, foot and mouth disease, which has no connection to the foot and mouth disease appearing in animals. The virus is transmitted through respiratory system secretions or through contact with feces, therefore hand hygiene after visiting the restroom is critical.
What are the symptoms: The disease usually starts with a fever and a general bad feeling, and after a day or two painful blisters appear in the oral cavity, on the tongue and on the inner side of the cheeks. Simultaneously a vesicular rash appears also on the palms of the hands and the feet, and sometimes also on the buttocks. The pain in the mouth may be so intense that the child refuses to drink, which significantly increases the risk of dehydration.
Is there a vaccine: There is no vaccine against these viruses.
What is the treatment: The treatment focuses on pain relief. Pain relievers and local anesthetic materials for the oral cavity can be used. It is important to offer children cold and soft foods, such as ice cream or yogurt, which do not irritate the sores, and to ensure small and continuous drinking throughout the day.
Norovirus
The Norovirus is the world's leading cause of viral stomach and intestinal infections. It is considered one of the most contagious viruses, as a very small amount of virus particles is enough to cause disease. The virus is very resistant to regular disinfectants and can survive for a long time on surfaces such as door handles or toys.
What are the symptoms: The disease breaks out suddenly, sometimes a few hours after infection. The main symptoms are severe vomiting and watery diarrhea, accompanied by intense abdominal pain, nausea and low fever. Due to the rapid loss of fluids, patients may feel dizziness, extreme weakness and a decrease in urination. In most cases the symptoms pass within about 48 to about 72 hours.
Is there a vaccine: There is no available vaccine against Norovirus.
What is the treatment: The central goal in treatment is the return of lost fluids and salts. It is recommended to use oral rehydration solutions containing an accurate concentration of sugar and salts, as these are better absorbed by the body during diarrhea. Very carbonated or sweetened drinks should be avoided, as they may worsen the diarrhea.
<br>Parainfluenza
Parainfluenza viruses cause respiratory diseases similar to a cold, but they may be more severe in small children. There are four types of the virus, with type 3 being the most common during the spring and early summer period. The virus is transmitted in tiny droplets emitted during talking or sneezing.
What are the symptoms: In adults symptoms of a mild cold usually appear, but in infants and toddlers the virus may cause stridor, characterized by a barking cough and hoarseness. The virus may also cause inflammation of the trachea and bronchi, which manifests in shortness of breath and wheezing. The fever can be high and last several days.
Is there a vaccine: There is no vaccine against the parainfluenza virus.
What is the treatment: The treatment for stridor usually includes exposure to cool air or use of inhalation devices with salt water. In more severe cases doctors may give steroid treatment to reduce the swelling in the respiratory tract. It is important to monitor the child's breathing rate and seek medical treatment if a real difficulty in breathing appears.
Rhinovirus
The Rhinovirus is the virus responsible for most cases of the common cold that we experience. Although it is active all year round, the changes in the weather and the increased use of air conditioners in May cause drying of the nasal mucosa, which makes it easier for the virus to penetrate the body. The virus spreads easily in closed places and through hand–to–hand contact.
What are the symptoms: The symptoms include nasal congestion, clear runny nose, sneezing, mild sore throat and cough. Usually a high fever does not appear in adults, but in children a fever of about 38 degrees is common. The disease is usually mild and passes within a week, but it may complicate into an ear infection or sinus infection in sensitive people.
Is there a vaccine: There is no vaccine due to the enormous number of different virus strains.
What is the treatment: The treatment is for symptom relief only. It includes use of salt water nasal sprays, plenty of drinking, rest and taking drugs for fever reduction and pain relief as needed. Strict adherence to hand washing is the best way to prevent infection within the house and work environment.
<br>When to urgently seek medical examination?
- Any fever in an infant under the age of 3 months
- Fever for more than 3 consecutive days
- Shortness of breath: Wheezing, rapid breathing, inability to complete a sentence or blue lips
- Multiple vomiting – more than 3 in a row
- Watery diarrhea
- Lack of urination for over 10 hours
- Skin bleeding
- Clouded consciousness
- Headache that wakes from sleep and fear of light