Human adenovirus is a common cause of respiratory infections in children under five years of age, accounting for approximately 2–5% of acute respiratory infections.
About 29% of children infected with adenovirus develop pneumonia, which can progress rapidly and is a major cause of pediatric mortality. In severe cases without timely treatment, mortality may reach approximately 50%, and survivors often develop long-term complications such as pulmonary fibrosis, bronchiectasis, and bronchiolitis obliterans.
Despite the severity of adenovirus-associated pneumonia, no globally approved standard treatment exists for pediatric patients. Current management consists of supportive care: antipyretics, rehydration, anti-inflammatory therapy, anti-asthmatic treatment, and oxygen therapy.
In 2026, Chinese researchers aimed to develop an effective and safe reference treatment regimen for children with adenoviral pneumonia. The key component of this regimen was local antiviral therapy using inhaled recombinant human interferon-α2b (IFN-α2b), combined with supportive symptomatic treatment.
After seven days of therapy, compared with supportive treatment alone:
- clinical symptoms of pneumonia resolved 17% faster;
- clinical recovery rate increased from 49% to 70%;
- overall clinical treatment efficacy rose from 86% to 97%;
- viral DNA was less frequently detected in nasopharyngeal swabs – 71% versus 53%;
- systemic inflammatory markers decreased;
- levels of antiviral proteins increased by 26–39%.
Safety was monitored daily, including vital signs, critical liver and kidney biochemical parameters, and adverse event frequency. No statistically significant differences were observed between children receiving IFN-α2b inhalations and those receiving standard therapy.
The investigators concluded that aerosolized recombinant human interferon-α2b is a safe and effective treatment for adenovirus-induced pneumonia in children.
Study Details
The study included 140 children under five years of age hospitalized with adenovirus-induced pneumonia. Typical symptoms included cough, sputum production, wheezing, dyspnea, and pulmonary crackles. Adenovirus infection was confirmed in all participants by PCR testing.
Only children whose symptoms had appeared less than 2 days before hospitalization were included, and all participants were ensured to be at comparable stages of disease progression, with observed outcomes reliably attributed to the treatment regimen rather than to differences in disease stage.
Participants were assigned to two equal groups. One group received supportive therapy only, while the second group received additional aerosolized IFN-α2b inhalations twice daily for 7 days.
Results
Researchers assessed not only clinical effectiveness but also treatment failure. Therapy was considered ineffective if clinical indicators did not improve or worsen. In the supportive therapy group, 14% of patients met this criterion, compared with only 3% in the IFN-α2b inhalation group.
Treatment efficacy was also evaluated by measuring four proinflammatory proteins. Three were significantly lower in the IFN-α2b group:
- tumor necrosis factor – reduced by 19%;
- interleukin-6 – reduced by 34%;
- C-reactive protein – reduced by 32%.
The only marker that was slightly higher in the new treatment group was lactate dehydrogenase, which increased by 4%.
These proteins were selected because elevated levels during adenovirus infection are associated with more severe disease.
Another important outcome measure was the level of antiviral proteins. Among the hundreds of antiviral proteins produced in the body, the researchers focused on two well-characterized molecules with critical functions against DNA viruses such as adenovirus.
The first protein, OAS, inhibits the synthesis of components required for the formation of new viral particles. The second protein, β2M, assists cytotoxic T lymphocytes in recognizing and eliminating virus-infected cells. Children receiving only supportive therapy produced, on average, 26% less OAS and 39% less β2M than those receiving additional IFN-α2b inhalations.
Safety of the treatment regimen, including IFN-α2b inhalation, was evaluated across several parameter groups:
- Vital signs, monitored daily: bronchoscopy findings, respiratory rate, heart rate, diastolic blood pressure, and body temperature. In both groups, these values remained within physiological ranges and did not differ significantly.
- Critical biochemical parameters of liver and kidney function: alanine aminotransferase, aspartate aminotransferase, urea, and creatinine. No statistically significant differences were observed between groups before or after treatment.
- Adverse event frequency: 7% in the IFN-α2b group and 4% in the supportive therapy group. All adverse events in both groups were mild and required no additional medical intervention.
Based on these results, the investigators concluded that inhaled recombinant human interferon-α2b represents an effective and safe antiviral therapy for children hospitalized with adenoviral pneumonia.
