With the number of cases of and deaths from a recently emerged respiratory disease climbing, the United Nations World Health Organization (WHO) is recommending new screening measures at airports in four countries in a bid to reduce any further international spread of the illness, known as severe acute respiratory syndrome (SARS).

Ten days into the outbreak of the previously unrecognized disease known as Severe Acute Respiratory Syndrome (SARS), the United Nations World Health Organization (WHO) today announced that two different viruses have now been identified in patient specimens as the possible source of the deadly illness.