Among the abnormal chest radiographs (49/118), bilateral involvement (28/49) was more commonly noted. The commonest presentations were bi-basal air space infiltrates (12/49), perihilar mixed reticular and alveolar infiltrates (13/49) and unilateral basal air space opacity (6/49). Less common findings were round opacity (1/49), scattered focal air space opacity (4/49), linear opacities (2/49), linear opacities that progress to alveolar opacities (3/49), plethoric lungs (2/49), bronchiolitis (2/49) and pleural effusion (4/49). In the majority of patients (43/49), there was radiological improvement in the follow-up chest radiographs. Five had progressive alveolar consolidation ranging from 2 to 13 days with one developing acute respiratory distress syndrome (ARDS) according to the American-European Consensus Conference (AECC) criteria. Five patients had CT done 2 days to 1 week after the last chest radiograph because they showed poor clinical response to initial treatment. Three were HRCT and the common findings were widespread interstitial shadowing, ground-glass change and atelectasis. These were not detected on plain chest radiographs. [6] . In Malaysia, the first confirmed case was a 21-year-old student who returned from Newark, USA, on a Malaysia Airlines flight MH091 on May 15, 2009. He presented with typical influenza symptoms -fever, sore throat and body aches. The first death occurred on July 24, 2009, where a 30-year-old Indonesian student who returned to Malaysia from a holiday break in Medan on July 5 had progressive fever and cough and eventually died [8] . As of October 17, 2009, there had been 77 H1N1-related deaths in Malaysia [7] . This made Malaysia the 36th country worldwide to be affected by the virus.