Sales of pork in the country are dropping but not because of the dreaded swine flu virus, the National Federation of Hog Farmers Tuesday.

Eliseo Yu, president of the National Federation of Hog Farmers, said the drop in the sales of pork nationwide is part of an annual market cycle in the country.

"During this period of time the sales of pork usually declines. It's a cycle every year during school vacation," Yu told ABS-CBN morning show "Umagang Kay Ganda."

Yu said the drop in sales is not an offshoot of the swine flu outbreak in Mexico and United States.

He pointed out that hog raisers regularly administer flu vaccines in piggery farms to prevent large-scale swine flu incidences.

Don't blame pigs

Dave Catbagan, director of the Bureau of Animal Industry (BAI), meanwhile clarified that swine flu virus is just a name and does not necessarily mean that the deadly virus originated from pigs.

"Pigs are not the culprits here," Catbagan said. He said that based on accounts of the International Society for Infectious Diseases (ISID), the so-called swine influenza virus actually originated from humans.

"Mexicans infected by the virus did not have any contact with pigs," Catbagan said, citing the observation of the ISID.

He said that the ISID has been urging the dropping of the word "swine" from the virus' name and replace it with the word "human."

"The experts want it called A (H1N1) human virus," he said.

No swine flu in RP

The Department of Health (DOH) on Monday allayed fears of the possible spread of the deadly swine flu virus in the Philippines.

"There is no report of swine flu among humans in Philippines...Following the World Health Organization alert among member states, the DOH has stepped up surveillance measures to prevent the entry of the virus that has killed 81 people in Mexico," Health Secretary Francisco Duque said in a press conference in Manila.

Duque said the BAI has not reported any recent case of swine flu among hogs in Pangasinan, contrary to some newspaper reports. He also said that the swine flu virus in pigs is different from the "entirely novel [virus] strain" that has affected humans in Mexico, the United States, and Canada.

The strain of Ebola Reston virus in hogs detected in a farm in Bulacan province last year is also different from the H1N1 virus strain in Mexico.

Duque said the government has enough stockpile of Tamiflu (oseltamivir), the anti-viral drug used to treat various types of flu. The government had increased its supplies of Tamiflu for its avian flu virus readiness plan.

Transmission by air

Dr. Eric Tayag, chief of the DOH-National Epidemiology Center, said the swine flu virus is spread via aerial droplets and could be passed from pig to human or human to human. He said infected individuals could exhibit symptoms of the illness three to five days after being infected.

He said the symptoms of the swine flu virus affecting humans are similar to the common flu virus. Among the symptoms are: fever, muscle pains, sore throat, cough, cold, and even diarrhea and vomitting.

Tayag said many of the victims in Mexico are between 25 to 48 years old.

In case the government suspects that an individual in the Philippines has the swine flu virus, Duque said it will have to take a tissue sample from the person and send it to the World Health Organization (WHO) to see if it is the same strain as the one found in Mexico.

The DOH also clarified that a person cannot get the swine flu virus by eating pork.

Tayag said a pandemic usually occurs every 10 to 40 years, and that the last pandemic happened in 1968. He said the virus in Mexico has the potential to be a pandemic if it is not contained.