Why do some children fall ill several times a year while others seem to be constantly battling colds? When are frequent infections normal, and when might a serious condition be hiding behind familiar symptoms?

Fever, a lingering cough, persistent runny nose and repeated colds are among the most common reasons parents consult a pediatrician. The problem becomes particularly noticeable when a child starts attending kindergarten or daycare and comes into contact with more infections. However, not every frequent cold indicates a weakened immune system. What matters is not only the number of illnesses but also their duration, severity, complications and the child's overall condition.

What Do International Statistics Tell Us?

According to the American Academy of Pediatrics (AAP, 2026), children in their first two years of life may experience an average of 8–10 colds each year. Respiratory infections generally become less frequent with age. At the same time, UNICEF statistics highlight the importance of promptly identifying serious illnesses. According to international estimates for 2024, lower respiratory tract infections, including pneumonia, accounted for approximately 13% of all deaths among children under five worldwide. There is also encouraging evidence. According to the World Health Organization (WHO, 2024), global vaccination programs have prevented approximately 154 million deaths over the past 50 years. These figures emphasize the importance of prevention, timely diagnosis and appropriate treatment. An ordinary viral cold must, however, be distinguished from illnesses requiring closer medical attention. Where is the boundary between the natural development of immune defenses and a pathological condition? Which treatment mistakes do parents make most often, and why should antibiotics not always be the first response?

We discussed these questions with Gulnoza Kamoliddinovna Azizova, pediatrician and pediatric gastroenterologist, Doctor of Philosophy (PhD) in Medical Sciences.

Interview with a Pediatrician: 15 Important Questions About Children's Health

1. Many parents complain that their child is ill almost every month. How many colds per year are considered acceptable at different ages, and when should frequent illnesses become a cause for concern?

Young children experience colds much more frequently than adults, and this alone does not indicate an immunodeficiency. According to the AAP, children in their first two years have approximately 8–10 colds per year, particularly if they attend daycare. In school-age children, infections generally become less frequent, averaging around four episodes annually, although individual variation is considerable.

The main criterion is not the number of episodes on the calendar, but the nature of the illnesses. If a child grows and gains weight normally, feels well between episodes and recovers without unusual complications, this is more likely to represent a normal age-related pattern. Warning signs include recurrent confirmed pneumonia, severe bacterial infections, hospitalizations, prolonged fever, poor weight gain and repeated need for intravenous antibiotics.

I therefore advise parents to keep a simple illness diary: date, symptoms, duration, confirmed diagnosis and treatment. It provides more useful information than a general impression that the child is “always sick.” [1, 4]

2. Why do some children seem constantly ill after starting kindergarten or daycare? Is this a natural stage of exposure to infections, or could it indicate an underlying health problem?

The main reason is a sharp increase in exposure to respiratory viruses. In groups of young children, infections spread more easily through the air, hands and shared objects. At the same time, children have not yet developed immune memory to many viruses, so colds may follow one another during the first period of daycare attendance.

However, it is important not to draw the mistaken conclusion that a child must go through numerous infections to “train” the immune system. The immune system develops without deliberate exposure to infection, and infections can sometimes cause complications. It is better to reduce transmission risks: wash hands, ventilate rooms, follow the vaccination schedule and keep a child out of group activities when clearly ill and unable to participate normally.

If frequent infections are accompanied by poor growth, persistent wet cough, repeated episodes of pneumonia or unusually severe illness, another cause needs to be investigated, ranging from asthma and allergies to disorders of immune defense. [1, 4]

3. Parents often say, “My child has a weak immune system.” What does this actually mean in pediatrics, and what signs may suggest an immunodeficiency?

“Weak immune system” is not a medical diagnosis. A healthy child's immune system may function normally despite frequent seasonal viral infections. A true immunodeficiency is an established defect in specific mechanisms of immune defense; it may be congenital or acquired, for example through severe malnutrition or the use of certain medications.

According to the American Academy of Allergy, Asthma & Immunology, warning signs include infections caused by unusual pathogens, recurrent pneumonia, deep abscesses, infections that are difficult to treat with standard therapy, poor growth or weight gain, and a family history of immunodeficiency. A combination of findings matters more than any isolated count of colds.

When there is a justified suspicion, the pediatrician begins with the medical history, examination and targeted investigations and, if needed, refers the child to a pediatric immunologist. Buying an “immunomodulator” without a diagnosis is neither diagnosis nor treatment. [4, 15]

4. How dangerous is a high temperature in a child? When can a fever be monitored at home, and when is urgent medical attention necessary?

Fever is a manifestation of the immune response, not an independent measure of infection severity. In children older than six months, breathing, activity, responsiveness, fluid intake, urination and general condition matter more than the thermometer reading alone. When a child is otherwise well, has no warning signs and can be monitored reliably, a mild fever can often be managed at home with adequate fluids and observation.

There are important age-related exceptions: a temperature of 38°C or higher in an infant younger than three months requires urgent medical assessment; in children aged 3–6 months, a temperature of 39°C or higher calls for prompt examination. Immediate help is needed for difficulty breathing, marked drowsiness or unresponsiveness, seizures, signs of dehydration, neck stiffness or a rash that does not fade when pressed.

Fever-reducing medications should primarily be used to relieve discomfort, at an age- and weight-appropriate dose. Aspirin must not be given to children with a viral infection. If fever persists for five days or more, the child needs assessment, including consideration of Kawasaki disease and other causes. [5, 10]

5. A common mistake is starting antibiotics independently for a cough, runny nose or fever. Why is this dangerous, and when are antibiotics truly needed?

Most common colds are caused by viruses, against which antibiotics do not work. Uncontrolled antibiotic use raises the risk of adverse reactions, disrupts the microbiota and contributes to bacterial resistance. Moreover, starting treatment without an examination can obscure the true cause of the illness.

Antibacterial treatment is needed for a confirmed or reasonably suspected bacterial infection—for example, certain types of pneumonia, urinary tract infection, streptococcal tonsillitis following appropriate testing, and some cases of middle-ear infection. In bacterial sinusitis, clinicians consider symptoms lasting more than ten days without improvement, renewed worsening after initial improvement, or a severe onset with high fever and purulent discharge.

A physician selects an antibiotic according to the diagnosis, the child's age and weight, allergies and local bacterial resistance patterns. Green nasal discharge or fever alone is not an automatic indication for antibiotics. [6]

6. Can what initially seems like an ordinary cold develop into pneumonia? Which early symptoms should alert parents, even if the fever has already subsided?

Yes. Sometimes a viral infection affects the lower respiratory tract, and sometimes a bacterial infection develops on top of it. However, not every prolonged cold leads to pneumonia, and the color of mucus alone cannot establish the diagnosis.

Early warning signs include rapid breathing at rest, retraction of the spaces between the ribs or lower chest during inhalation, shortness of breath, chest pain, marked weakness, refusal to drink and deterioration after a period of improvement. In infants aged 2–12 months, 50 or more breaths per minute is a threshold for rapid breathing; from one to five years, 40 or more breaths per minute. These are screening indicators, not substitutes for a physician's assessment.

Importantly, a fall in temperature does not rule out pneumonia. If breathing becomes labored, the child develops bluish discoloration, cannot drink or appears markedly lethargic, emergency care is needed. Chest X-rays are performed when clinically indicated, not for every child with a cough. [7, 5]

7. If a child's cough continues for several weeks after an illness, is it always a lingering symptom? Which conditions should be ruled out first?

No, although a cough can indeed persist for some time after a viral infection. According to CHEST guidelines, a daily cough lasting longer than four weeks in a child should be regarded as chronic, and its cause should be investigated.

Assessment begins with the characteristics of the cough: whether it is wet or dry, occurs during the day or at night, is associated with exercise, and whether there is wheezing, coughing after meals, fever or poor weight gain. Possible causes include asthma, protracted bacterial bronchitis, pertussis, allergies and ear, nose and throat disorders. If the cough began suddenly after a choking episode, an inhaled foreign body must be excluded.

If a cough occurs daily for more than four weeks, the child needs an examination and, when indicated, chest radiography and spirometry if old enough to perform the test correctly. Cough syrups or antibiotics should not be prescribed for months without identifying the cause. [8, 14]

8. Parents often use nebulizers, cough syrups and various medications on their own. Which home treatments may be ineffective or even dangerous for a child?

The greatest risks are associated with uncontrolled use of combination “cold remedies,” cough suppressants, antibiotics and inhaled medicines. The FDA does not recommend over-the-counter cough and cold medicines for children under two years; manufacturers generally label these products as unsuitable for children under four. Some preparations contain several active ingredients, making accidental double dosing easy.

A nebulizer is a device for delivering a prescribed medicine, not a universal treatment for a runny nose. In typical bronchiolitis, NICE does not recommend routine use of inhaled bronchodilators or corticosteroids. Steam inhalation over hot water is also dangerous because it can cause burns.

For an uncomplicated cold, adequate fluids, rest, saline nasal drops or sprays and gentle age-appropriate nasal clearing are usually sufficient. For children older than one year, a small amount of honey may sometimes reduce nighttime coughing; honey is contraindicated before the age of one because of the risk of botulism. [9–11]

9. Vitamins, immunomodulators and products marketed to “strengthen immunity” are widely advertised. Is there convincing scientific evidence that they work, and what genuinely helps protect children's health?

There is no universal medication that “boosts” a healthy child's immune system and reliably prevents colds. For most advertised immunomodulators, convincing evidence from high-quality pediatric studies is lacking. Correcting a proven deficiency is a separate matter: for example, vitamin D is important under age-specific recommendations to prevent rickets, but this does not mean that high doses protect against respiratory viral infections.

Notably, an updated 2025 meta-analysis combining 46 randomized trials and more than 64,000 participants found no statistically significant overall preventive benefit of vitamin D supplements against acute respiratory infections. A Cochrane review likewise did not establish a reduction in the frequency of colds in the general population with regular vitamin C intake, although the duration of symptoms may be slightly shorter.

The best-supported measures are vaccination, balanced nutrition, adequate sleep, avoiding tobacco smoke, good hygiene and timely treatment of specific diseases. Vitamins should be prescribed for medical indications, not as a substitute for these measures. [12, 13, 3]

10. Can persistent nasal congestion or a recurring cough be caused by allergies, bronchial asthma or enlarged adenoids rather than infection? How can these conditions be distinguished?

Yes, and this is one of the common sources of diagnostic mistakes. Viral infections typically begin relatively suddenly and improve gradually. Allergic rhinitis often involves repeated sneezing, itchy nose or eyes, watery discharge, an association with pollen, household dust or animals, and no significant fever.

With asthma, wheezing, shortness of breath, chest tightness and coughing may recur, especially at night or during exercise. However, an isolated cough does not by itself prove asthma: diagnosis is based on the overall symptom pattern and, when age permits, objective testing of lung function.

Enlarged adenoids may cause persistent mouth breathing, snoring, nasal obstruction and recurrent middle-ear infections. Clarification may require assessment by a pediatrician, allergist, ear-nose-throat specialist or pulmonologist. These conditions should not be treated independently with antibiotics for months. [14, 19, 20]

11. Parents sometimes request as many tests as possible to find the cause of frequent illnesses. Which investigations have real diagnostic value, and which are usually unnecessary?

Good diagnosis starts not with a large package of laboratory tests but with a detailed history, review of height and weight, vaccination status and examination of the lungs, nasopharynx, skin and lymph nodes. A healthy child with typical viral colds usually does not need extensive laboratory testing.

If there are signs of anemia, nutritional problems or prolonged inflammation, the physician orders targeted tests. When immunodeficiency is reasonably suspected, initial tests may include a complete blood count with differential and quantitative IgG, IgA and IgM levels interpreted using age-specific reference ranges; depending on the clinical picture, complement studies, post-vaccination antibody levels and other specialized investigations may follow. A persistent cough calls for a different diagnostic approach.

Without specific indications, broad “immune panels,” tests for every possible virus, extensive allergen panels or tumor markers should generally be avoided: they often produce results that are difficult to interpret and do not change treatment decisions. [15, 8]

12. What roles do sleep, nutrition, iron deficiency, physical activity and environmental conditions play in the frequency and severity of childhood illnesses? What should parents prioritize?

Everyday lifestyle factors do not create a “super immune system,” but they significantly affect general health and a child's ability to cope with illness. A varied, balanced diet with adequate protein, iron and other nutrients is important. Iron deficiency can cause weakness and anemia; testing and treatment should depend on age, diet and risk factors rather than the assumption that “every child needs iron supplements.”

Sleep is particularly important. According to CDC guidance, children aged 1–2 years need about 11–14 hours of sleep per 24 hours, those aged 3–5 years need 10–13 hours, and those aged 6–12 years need 9–12 hours. Daily outdoor time and age-appropriate activity support overall health but do not replace medical prevention.

One of the most important steps is to completely eliminate tobacco smoke from the home and car. Secondhand smoke is known to increase the risk of respiratory infections, ear infections and severe asthma attacks in children. [16, 17]

13. Some parents are afraid to vaccinate children who frequently get sick. When should vaccination actually be postponed, and is a frequent cold itself a contraindication?

A history of frequent colds is not in itself a contraindication to vaccination. According to CDC recommendations, a mild upper respiratory infection, slight runny nose or low-grade fever usually does not require postponing a scheduled vaccine. The clinician makes the final decision after assessing the child's current condition and the specific vaccine.

Postponement is generally considered during a moderate or severe acute illness, primarily to avoid confusing symptoms of the illness with possible post-vaccination reactions. True contraindications vary by vaccine: examples include a severe allergic reaction to a previous dose or a vaccine component; certain live vaccines are contraindicated in some severe immunodeficiency conditions.

Timely vaccination may be particularly important for children at increased risk of serious infections. Parents should not independently delay vaccinations for months because of every runny nose; if doses have been missed, discuss an individualized catch-up schedule with the pediatrician. [18, 3]

14. Which symptoms in a child must never be ignored? Name the warning signs that require immediate emergency medical attention rather than waiting until the next day.

Call emergency medical services immediately if a child has severe breathing difficulty, chest retractions, blue lips or skin, pauses in breathing, failure to respond, seizures, profound weakness or altered consciousness. Inability to drink or feed, severe dehydration, fever with neck stiffness, and a red-purple rash that does not fade when pressed are especially concerning.

An infant younger than three months with a temperature of 38°C or higher needs urgent medical assessment even if the baby appears relatively calm. In children aged 3–6 months, a temperature of 39°C or higher also requires prompt evaluation.

A separate emergency is sudden coughing and choking during eating or playing with small objects: a foreign body in the airway must be suspected. The key rule is to assess not only the thermometer but also breathing, consciousness, skin color, drinking and the speed at which the child's condition is worsening. [5, 7]

15. If you could give parents only three recommendations to reduce the risk of serious illnesses in children, what would they be? And which common mistakes in caring for children's health do you consider most dangerous?

First, vaccinate children on schedule and do not skip preventive checkups. Vaccination prevents a number of potentially serious infections and is one of the most effective public health measures.

Second, build health-promoting habits every day: balanced nutrition, enough sleep, physical activity, clean air free from tobacco smoke and routine hand hygiene. These measures may sound less impressive than advertisements for “immune-boosting drugs,” but they have much stronger scientific support.

Third, recognize warning signs and seek medical care promptly, especially for breathing difficulties, dehydration, altered consciousness and unusually severe illness. The most dangerous mistakes are uncontrolled antibiotic use, relying on unproven remedies instead of appropriate assessment, missed vaccinations and trying to “wait out” signs of a medical emergency. Parents do not need to become doctors; they need to know when home care is no longer enough. [3, 5, 6, 17, 18]