The number of people infected by influenza A(H1N1) virus in the country has climbed to 147, but health officials said there's no cause yet for alarm as the new flu strain is not as deadly as SARS and avian flu. The Department of Health (DOH) confirmed on Sunday 36 new cases, including three foreigners. Despite the continuous increase in the number of A(H1N1) cases in the country, the Commission on Education (CHED) said classes in college and universities will have to open on Monday. “We do not have to panic. We are taking all precautions, and we cannot afford to postpone classes anymore,” said CHED chairman Emmanuel Angeles. Health Secretary Francisco Duque said the new swine flu strain has not yet evolved into a deadlier threat similar to that of SARs and avian flu that killed hundreds of people worldwide in 2003. Dr. Eric Tayag, chief epidemiologist of the Department of Health (DOH), said health officials “have not detected any serious community level (transmission of the disease) at least here in Manila.” But Tayag noted that the situation remains fluid and that the virus could still evolve into a far deadlier viral strain, citing the behavior of the Spanish influenza virus, which started mild but turned out more deadly when it reemerged. The Spanish influenza virus, which is similar to the H1N1 strain, killed 50 to 100 million people and infected 500 million others in 1918, Tayag said. But he noted that during that time, public health systems were not as advanced as they are nowadays. Tayag also explained the differences between H1N1 and other recent epidemics that hit the world. He said unlike H1N1, the avian flu virus had a “more definite” behavior as it was ascertained that humans who contracted the disease had been exposed to birds. SARS also has a “stable identity,” Tayag said. “Because the disease was severe and the patient needed to be hospitalized, the spread of the disease was contained. Only doctors and nurses taking care of the patient contracted SARS.” But he said H1N1's behavior is new and unusual. “It's not sure whether it wants to kill or just spread a mild disease similar to that of common flu,” he said. The H1N1 fatality rate is currently low at only 0.5 percent. SARS and avian flu killed about half of their victims, while dengue in the Philippines has a fatality rate of one to two percent, health officials said. The World Health Organization (WHO) earlier declared that H1N1 cases worldwide have reached the pandemic stage, the first time in 40 years that such a declaration was made.