January 30, 2009

Four more pig farm workers in the Philippines have tested positive for a strain of the Ebola virus that isn't deadly to humans, taking the number of human cases to five, the government said Friday (January 30).

 

The Philippines has suffered an outbreak of the Ebola-Reston virus among pigs, and Health Secretary Francisco Duque said it was possible the farm workers were infected by the animals.

 

One farm worker was last week confirmed to have been infected by the disease, and Duque said Friday the number of human cases had now reached five.

 

If a link is proved, it would be the first time humans have contracted the disease from pigs.

 

World Health Organization expert on infectious diseases Julie Hall said the virus still posed "low risk" to human health.

 

The government quarantined farms in the Philippine towns of Pandi and Talavera after the Ebola-Reston virus was discovered in pigs in July 2008.

 

Ebola-Reston was first detected in 1989 in laboratory monkeys sent from the Philippines to Reston, Virginia, in the US. Unlike its African counterparts, it hasn't proved deadly.

 

The workers aren't the first human case of the Ebola-Reston virus.

 

Twenty five people who came into contact with the infected laboratory monkeys in 1989 tested positive for the virus. Only one showed signs of sickness, suffering from flu-like symptoms, but quickly recovered.

 

"There are still a lot of unanswered questions about this particular virus," Hall said.

 

"These are humans who are young, fit and healthy," she said, adding there was no telling what the virus could have done "if other individuals who do not have robust immune systems were to be infected."

 

The UN sent a team of medical specialists to the Philippines last month after four pigs tested positive for a strain of Ebola that was first found in monkeys exported by the Philippines to a US laboratory in Reston, Virginia. The team gathered blood samples from 77 people who may have been exposed to the virus.

 

The other known Ebola strains are deadly to humans.

 

Duque said three of the five men were from the quarantined farms, but all the men are "healthy and have not been seriously ill in the previous 12 months."

 

The workers aren't the first human cases of the Ebola-Reston virus.

 

Twenty-five people who came into contact with the infected laboratory monkeys in 1989 tested positive for the virus. Only one showed signs of sickness, suffering from flu-like symptoms, but quickly recovered.