In brief
- In adults, a respiratory viral infection usually starts gradually: fever, weakness, headache, muscle aches, then a scratchy throat, cough and runny nose [1].
- With adenovirus infection, the lymph nodes may swell, and less often the liver [1].
- Antibiotics are not recommended for an uncomplicated respiratory viral infection [1].
- With symptoms, the guidelines advise seeing a doctor, and with a temperature above 38.5 °C (101.3 °F), requesting a doctor's home visit [1].
When to see a doctor urgently
Russian Ministry of Health clinical guidelines for adults advise seeing a doctor for cold and flu-like (ARVI) symptoms and requesting a home visit from a doctor if your temperature is above 38.5 °C (101.3 °F). It is especially important to get medical help if [1]:
- you have a high fever;
- you become short of breath;
- a severe headache won't go away;
- you keep vomiting and it brings no relief;
- your blood pressure drops sharply.
Symptoms
According to the clinical guidelines, a respiratory viral infection (ARVI) in adults usually starts gradually. First come moderate general symptoms of illness (intoxication): fever, general weakness, headache, and muscle and joint pain. Then a scratchy throat, cough, runny nose and sometimes conjunctivitis follow [1].
A feature of adenovirus infection is lymphoproliferative syndrome: swollen lymph nodes and, less often, an enlarged liver [1]. In the airways, adenoviruses mainly cause pharyngitis, tonsillitis and bronchitis [1].
Besides the airways, adenovirus can affect the eyes and the gut, causing conjunctivitis or gastroenteritis with nausea, vomiting, diarrhea and stomach pain [2]. More in the articles on conjunctivitis and the gastrointestinal form.
How long it lasts
The incubation period of ARVI is 1 to 14 days, and 1 to 5 days for the most common viruses [1]. The acute illness lasts 5–10 days; if it continues for 11–30 days it is called subacute, and longer than 30 days, prolonged [1].
Who is at higher risk
Your doctor needs to know about chronic lung, heart or blood vessel disease, metabolic disorders, kidney and liver disease, immunodeficiency, cancer, and also if you are over 65 or pregnant: all of these are risk factors for severe and complicated illness [1].
CDC notes separately that severe adenovirus infection is more common in people with weakened immune systems and with respiratory or heart disease [2].
Complications
A bacterial infection can follow ARVI: ear infection, sinusitis, bronchitis, pneumonia. Severe complications are more common in older people with other health conditions [1]. ARVI is linked to 30–50% of cases of community-acquired pneumonia [1].
Treatment
There is no specific treatment for adenovirus infection; the symptoms are treated [2]. According to the clinical guidelines, basic care for adults is bed rest, a suitable diet and plenty of fluids [1]. Fever reducers and pain relievers are used only to ease symptoms [1].
Antibiotics are not recommended for uncomplicated ARVI during the first 10–14 days [1]. More in adenovirus treatment.
How not to infect your family
For prevention, the clinical guidelines advise wearing a mask in public places; a mask works as long as it stays dry [1]. The sick person should have their own dishes and personal care items [1]. Thorough handwashing, cleaning surfaces around the sick person and airing the room are important [3].
“It is also important to follow personal hygiene: don't touch your eyes or face after being in public places, wash your hands often during the day, and do regular damp cleaning at home and at work so dust doesn't build up”
Izvestia (in Russian), May 24, 2023
Frequently asked questions
What are adenovirus symptoms in adults?
In adults, a respiratory viral infection usually starts gradually: fever, weakness, headache, then a scratchy throat, cough and runny nose. With adenovirus, lymph nodes may swell [1].
When should an adult with adenovirus see a doctor?
Russian guidelines advise going to an outpatient clinic if you have cold symptoms, and calling a doctor to your home if your temperature is above 38.5 °C (101.3 °F) [1].
How long does adenovirus last in adults?
The acute phase of a respiratory viral infection lasts 5–10 days [1].
How adenovirus spreads
How you catch it, how many days a person is contagious, and what kills the virus.
Sources
- Russian Ministry of Health. Clinical guidelines “Acute respiratory viral infections (ARVI) in adults”, ID 724_2, published in the guidelines database on August 4, 2025 (in Russian). Accessed October 9, 2026.
- CDC (US Centers for Disease Control and Prevention). About Adenovirus. Updated December 16, 2025. Accessed October 7, 2026.
- Russian Ministry of Health, Union of Pediatricians of Russia. Clinical guidelines “Acute respiratory viral infection (ARVI)”, children, ID 25_3, published in the guidelines database on September 2, 2026 (in Russian). Accessed October 8, 2026.
This article was prepared by our editorial team from official sources and does not replace a doctor’s advice. Found an error? Write to us.