An outbreak of an influenza-like virus in Southeast Asia led many people to stockpile food at home and stock up on medicine, and the same factor may be happening in the case of a still-undiagnosed bat-borne virus, according to researchers who first reported on the supply boom.

The first case of hemorrhagic fever with respiratory disease, which did not appear to be related to a flu pandemic, was confirmed by health officials in Singapore last November. The epidemic was first suspected because of hospitals in some of the country's most densely populated areas reporting unusually high levels of admissions, especially for pneumonia and bronchitis. According to the Singapore Department of Health, they were linked to breathing infections possibly caused by a bat-borne virus called Nipah, whose resemblance to the SARS virus prompted speculation that it was the cause of the outbreak.

By the second week of December, the first case was confirmed in Kuala Lumpur, Malaysia. It involved a 49-year-old man with symptoms similar to those of Nipah, as well as bleeding and complications including pancreatitis and respiratory failure.

But some people mistook the spread of the virus for an epidemic, and began building stockpiles in anticipation of the economic and psychological disruption that would ensue, according to a study published Tuesday in the British Medical Journal. One company that ran promotions for people to stockpile food and medicine said that 60% of customers were men, and 90% of the products sold were related to medicine.

"One customer, a 64-year-old electrical engineer, had walked from Kota Kinabalu [Malaysia] to Singapore so that he could have a bucket of cash in his bedroom ready to exchange at the bank," said the study's lead author, Panthong Boonyaratgit, an epidemiologist at Duke-NUS Graduate Medical School in Singapore. "The level of panic is just spectacular."

The man who died was likely infected with the virus sometime after November. Nipah, which belongs to the family of serotype-11 bats in Asia and the Pacific Rim, can cause serious respiratory illness if it is not treated promptly.

Nipah disease is not as common as, say, SARS, but it has caused around 140 deaths and more than 1,000 hospitalizations since 2002. Although it is transmitted by the biting of a Nazhi bat, transmission is generally considered low-risk. The disease is caused by a virus that is recognized as distinct from all types of humans. Infection occurs when the virus enters the body through the nasal cavity or bloodstream, and not through the eyes, nose or mouth.

In the Philippines, the virus was discovered in 2010, and cases have been documented since, mostly at airports and entry points. A virus similar to Nipah has been found in bats in India, Sri Lanka and Malaysia. An outbreak of kidney failure in central Thailand in 2007 was partly attributed to infections from the bat-borne virus.

The question is whether such an outbreak could affect the huge infrastructure of the Southeast Asian economy, where people trade goods and services among themselves and families. The Philippines is particularly vulnerable to such outbreaks because it has no central government control in some areas and many of its remote areas are accessible only by boat.

Another risk is that they could spread from countries where they are already established to places where there are fewer resources to respond to cases. "For instance, the secondary market effect of pharmaceuticals, food, and travel services would become compounded by localized disaster funding fatigue," the authors wrote.

Doctors in Singapore immediately advised the public to avoid bats and close contact with them. With the medical community somewhat fearful of overplaying the potential exposure to the virus, panicking buyers started lining up at pharmacies across the country. Boonyaratgit saw the phenomenon in the forecourt of his pharmacy one day: "They were talking about a [H1N1] pandemic, and these visitors [who had filled out the pharmacy receipt] were afraid they were going to die and wanted to buy just enough to have the family around them for two days and not give it away."