"On the basis of the theoretical assumptions the alarm of the health authorities was justified, but fortunately the pandemic did not turn out to be as serious as expected," recalls the paediatrician Eider Oñate from her place of work in the Paediatric Intensive Care Unit at the Hospital Universitario Donostia-San Sebastian. She knows what she's talking about. She was in the firing line during the 2009 influenza A crisis. "What would have been inexcusable would have been the failure to adopt the measures that were taken, and that such caution should have turned out to be responsible for many avoidable victims." Oñate sought to quantify the impact of the pandemic on the paediatric population of Gipuzkoa, during as well as in the periods prior to and following the appearance and spread of the H1N1 virus. She has gathered the results into her thesis "Clinical and epidemiological features of the children hospitalised owing to infection by the influenza virus during the 2009 pandemic in Gipuzkoa: comparison with the pre- and post-pandemic period." The research has confirmed that in this sector of the population (one of the a priori risk groups), the impact of this influenza subtype was similar compared with that of seasonal flu, even though older children and young adults were the ones mostly affected.

The World Health Organisation (WHO) announced the "ongoing pandemic" in June 2009 and a set of protocols were activated in hospitals; as a result, all the cases of children suspected of being infected by influenza A were required to be studied in depth. The gathering of information that under normal circumstances is not obtained offered the chance to study, for the first time, in an organised health system and with the resources for viral diagnosis, the impact of the new virus on the population and on health care and its clinical and epidemiological behaviour. It was also a scenario that had not been repeated since 1968, the year of the previous flu pandemic caused by the appearance of a new strain of the influenza A virus.

The consequences of public alarm

The conclusion drawn from the analysis of the data indicates that influenza A caused mostly mild symptoms, even in patients belonging to risk groups, and mortality, as in non-pandemic flu, was low and lower than expected. Despite that, the study has also confirmed that, compared with the data prior to and following the pandemic, there was a substantial increase in the number of consultations handled by the emergency departments and an increase in the number of hospital admissions. "The public alarm had a lot to do with that," admits Oñate. "It not only changed the attitude of the population, but also the routine clinical practice of the paediatricians." So, when an asthmatic child with influenza A for example was involved, they acted differently without basing themselves so much on clinical training. Usually a child with asthma and common flu without any breathing problems is sent home, but during the pandemic the most usual thing was to have him/her admitted to hospital as a precaution.

Aside from the controversy on whether the actual severity of the crisis was distorted by factors outside the health sphere, Oñate stresses that the experience acquired after the first pandemic in the 21st century by the A (H1N1) pandemic influenza virus will make it possible to set up new diagnostic and therapeutic strategies over the coming years. Firstly, one should not allow oneself to be ruled by the alarm. At the same time, it would be necessary in the light of the new experiences to review and assess the strategies affecting the use of antiviral drugs, including the famous Oseltamivir, of proven effectiveness in specific situations. On a practical level it would be necessary to have available methods for early diagnosis that are sufficiently sensitive and reliable for detecting the flu and which would obviate the need for aggressive tests.

History has shown that sooner or later there will be another pandemic. "Nobody knows when it's going to happen again, but we are better prepared now," says the paediatrician, but she issues a warning. "Yes, we could have one as virulent as that of 1918. In these situations you have to prevent contagion and stop it spreading." The paediatrician cites Asia as the possible source where it could emerge, and highlights the importance of the world surveillance network to detect the appearance of new strains sufficiently in advance. "One should not be afraid of flu, but it is important that the people for whom vaccination is recommended be vaccinated," she concludes.