MANILA, July 7: The World Health Organization (WHO) warned on Monday that the Sars epidemic can re-emerge in the next few months as doctors lacked an effective kit to diagnose the illness and with animals still harbouring the deadly virus.

In issuing the warning, Shigeru Omi, director for WHO Western Pacific region where 95 per cent of Sars cases were reported during the recent outbreak, said Sars-hit countries should maintain their surveillance systems for at least one more year.

More than 100 people mostly in Asia were still recovering from the illness and it was too soon to give the all-clear signal, he added.

Omi feared some patients could be carrying the coronavirus causing Severe Acute Respiratory Syndrome (Sars) although they seemingly had recovered from the pneumonia-like disease.

Those infected might also not display any Sars symptoms, making it impossible to detect them, he added.

WHO announced at the weekend that Sars had been contained worldwide, with Taiwan the last to be declared free of the disease.

It had killed more than 800 people and infected more than 8,400 in some 30 countries since it first emerged in the Chinese province of Guangdong in November.

“In addition to those factors (pointing to a possible reemergence of the disease), one thing that makes us more cautious is the possibility of Sars returning this winter” in the northern hemisphere, Omi said.

“Even if this virus does not come back, certainly there will be other diseases with similar symptoms coming up — influenza or common cold which represent similar symptoms as Sars.”

He said that unless a more sensitive diagnostic kit was developed before winter, “there is going to be a lot of confusion with so many possible cases overwhelming health systems.”

Diagnostic kits currently available can catch only about 70 per cent of Sars cases.

“In my view developing a more sensitive diagnostic kit is the most important priority in addition to being vigilant. Otherwise, we will have to, for example, quarantine all the influenza cases, which may be a very high number,” Omi said.

WHO at the weekend advised travellers to areas with “recent outbreaks” of Sars to continue to watch for the main symptoms: high fever, dry cough, shortness of breath or breathing difficulties.

Omi said WHO had expected an effective diagnostic kit to be developed as early as April “but three months have passed and it seems that it is not easy as we expected, especially in terms of sensitivity.”

For the world to be Sars-free, the coronavirus had to be wiped out, he said.

“For any virus to be declared eradicated, it has to meet certain conditions: its host should be only human, there should not be any chronic carriers of the illness, and there should be available a simple but effective diagnostic kit and an affordable vaccine.

“What we have achieved so far is only we have interrupted the human-to-human transmission of SARS. We have not wiped out the virus as it is very likely that animals are harbouring it,” he said.

Omi also said WHO would have to amend the “definition” of Sars cases following the UN agency’s weekend declaration that all Sars-hit countries are free of the disease.

“Previously, one of the elements that constitute suspected Sars cases is the history of travel by the patients to affected areas. Now, there are no areas that are affected, so we need to review this,” he said.—AFP