Expatriates raising a family in the inner city may wish to relocate to a more suburban location, following research that found children in denser urban areas are considerably more likely to develop asthma than the general populace.
Research published in the Journal of Infectious Diseases and undertaken by scientists at the University of Wisconsin indicated that this discrepancy could be the result of infections that urban youngsters develop in their early life.
Furthermore, the discovery could lead to the creation of innovative asthma treatments in children that might become available to international medical insurance policyholders.
Investigators led by Dr James Gern analysed nasal secretions from 500 infants in New York City, Baltimore, St Louis and Boston, before comparing these to samples from 285 children in the suburbs of Madison in Wisconsin.
They revealed that children from urban regions had lower levels of respiratory syncytal virus (RSV) and human rhinovirus (HRV) than their suburban counterparts, although they were more likely to test positive for adenovirus.
Scientists intend to continue analysing the urban youngsters in the study to determine if infection with the adenovirus can be linked to the reduced levels of lung function and higher rates of asthma seen in this demographic.
Adenovirus is known to cause persistent infections and the international healthcare specialists remarked that this could impact the development of the respiratory system.
Higher levels of adenovirus were found in all four urban locations in which the investigation was carried out and it is thought that the pervasiveness, mortality and morbidity of asthma in the inner city gives this investigation particular significance.
"This approach is likely to provide novel insights that will serve to guide the development of treatment interventions to decrease the prevalence and severity of asthma during childhood," Dr Peter Heymann and Dr Thomas Platts-Mills of the University of Virginia in Charlottesville said in an editorial that accompanied the story.