Dozen countries now fear fatal pneumonia

NewScientist.com news service

The spread of a highly infectious and deadly pneumonia continued around the globe on Monday, with the number of countries with confirmed or suspected cases rising to 12.

Unconfirmed cases have now emerged in the UK, Australia, Switzerland and Slovenia, all connected with travel to the Far East. Health authorities on all continents are taking the risk of importing the disease extremely seriously. The US, South Africa and Russia, amongst others, have put their health authorities on nationwide alert.

Eight cases in Canada, including two deaths, and two cases in Germany were announced over the weekend. However, the situation is a fast changing one and suspected cases in Indonesia and the Philippines have now been ruled out.

The mystery illness, which has been labelled Severe Acute Respiratory Syndrome (SARS), has swept around the world since the first of 48 cases was recognised in Hanoi, Vietnam on 26 February.

This case in turn may be linked to an earlier outbreak involving over 300 cases in China. In total, the illness is implicated in nine deaths and 500 infections. Most are in the Far East, with more than 100 cases in Hong Kong, 21 in Singapore, three cases in Taiwan and one in Thailand.

Air filters

The World Health Organization is not recommending travel restrictions at present. But it has issued guidelines to help airlines identify passengers who might be carrying the contagious disease.

This includes anyone with a fever above 38°C, a respiratory symptom such as cough or shortness of breath and either close contact with a person with SARS or recent history of travel to affected areas. Based on information from Canada and Hanoi, SARS appears to have an incubation period between two to seven days.

In a statement, the WHO acknowledges that: "The speed of international travel creates a risk of rapid spread to additional areas."

Hong Kong-based carrier Cathay Pacific said it had initiated "precautionary health measures". Its principal medical officer John Merritt told AFP that air filters in planes "remove many of the droplets and particles that are responsible for spreading infection". But he added that "it is important for passengers who appear to be ill to be denied boarding and referred for medical assessment."

The suspected UK case is in a man who flew from Hong Kong to Manchester, and is now in hospital. The airline concerned has been notified, the UK Public Health Laboratory Service stated, although the available evidence suggests the infection is only passed on in cases of close contact, to family members or health care workers, for example.

Bacteria, virus, fungus

Pneumonia is an inflammation of the lungs caused by a bacterial, viral, or fungal infection. Atypical pneumonia, as SARS was initially called, is usually caused by bacteria such as Legionella pneumophila, Chlamydia pneumoniae and Mycoplasma pneumoniae.

But the organism responsible for the SARS outbreak is yet to be identified. Chlamydia was implicated via lung X-rays in two deaths in the outbreak in China's Guangdong province, although a link to the Vietnam and Hong Kong outbreaks has yet to be confirmed.

The WHO is now co-ordinating a major international effort to find the cause, with 11 laboratories working on the project in 10 different countries. "These are the world's best laboratories working together to see if they can find a diagnosis for this disease," David Heymann, WHO's executive director for communicable diseases, told AFP News.

He said influenza was unlikely to be the cause of SARS, as flu spreads faster. Hong Kong bird flu has already been ruled out as a possible cause. Experts have also suggested that because the Guangdong outbreak eventually subsided, the disease may not have the potential for a very large epidemic, as others have feared.