Clinical features of severe cases of pandemic influenzaPandemic
H1N1 2009 briefing note 1316 OCTOBER 2009 | GENEVA — To gather information about the clinical features and management of pandemic influenza, WHO hosted a three-day meeting at the headquarters of the Pan American Health Organization in Washington, DC on 14–16 October. Findings and experiences were presented by around 100 clinicians, scientists, and public health professionals from the Americas, Europe, Asia, Africa, the Middle East and Oceania.The meeting confirmed that the overwhelming majority of persons worldwide infected with the new H1N1 virus continue to experience uncomplicated influenza-like illness, with full recovery within a week, even without medical treatment.
Need for intensive care : However, concern is now focused on the clinical course and management of small subsets of patients who rapidly develop very severe progressive pneumonia. In these patients, severe pneumonia is often associated with failure of other organs, or marked worsening of underlying asthma or chronic obstructive airway disease.Treatment of these patients is difficult and demanding, strongly suggesting that emergency rooms and intensive care units will experience the heaviest burden of patient care during the pandemic.Primary viral pneumonia is the most common finding in severe cases and a frequent cause of death. Secondary bacterial infections have been found in approximately 30% of fatal cases. Respiratory failure and refractory shock have been the most common causes of death.Presentations during the meeting explored the pathology of severe disease in detail, with findings supported by work in experimental animals. These findings confirm the ability of the new H1N1 virus to directly cause severe pneumonia. read more
