From recent observations in the Philippines and previous studies of ERV, the virus has shown it can be transmitted to humans, without resulting in illness. However, the evidence available relates only to healthy adults and it would be premature to conclude the health effects of the virus on all population groups. The threat to human health is likely to be low for healthy adults but is unknown for all other population groups, such as immuno-compromised persons, persons with underlying medical conditions, pregnant women and children.

Further epidemiological investigation and human testing is currently ongoing. .

Who is most at risk of being infected by Ebola Reston in pigs, and how can they protect themselves?

While pig-to-human transmission is strongly suspected in the case of the 5 Filipino pig handlers, it has not yet been confirmed. However, as a precaution, people should reduce direct contact with sick pigs in order to reduce the risk of possible pig-to-human transmission . Gloves and other appropriate protective clothing should be worn while handling sick pigs or their waste and when culling sick pigs.

We are advising that people who come into contact with sick or dead pigs should notify the authorities and ensure that the animals are destroyed and disposed of appropriately.

Sick pigs should never be consumed as there is a potential for a number of different diseases. If ill animals are encountered, proper disinfection of instruments, surfaces, facilities and clothing is also recommended with sodium hypochlorite or several commercially available detergents.

People processing pigs and pig meat should use good hygienic practices and report any ill animals to the authorities.

Can Ebola Reston virus be transmitted from person-to-person?

All the workers were found positive for IgG antibodies against ERV, produced by the body's natural defense cells against infection. They were not found positive for the virus. Three of the individuals were found negative for IgM antibodies; this tells us they likely acquired the infection over five months ago, have now fought off the virus and are no longer infectious.The IgM antibodies results for the two others are still pending.

Based on limited knowledge of ERV in humans and extrapolation of data from Africa, we can say that none of the positive individuals who are IgM negative are currently infectious. No public health measures are recommended for these IgM negative individuals at this point in time.

Is it safe to eat pork?

Should it enter the food chain, ERV in pork meat poses a negligible risk if the meat is handled safely and cooked thoroughly. Meat from healthy pigs is safe to eat IF it cooked properly, at 70°C, with no pink meat and with juices running clear. Good kitchen hygiene and regular hand washing – normal practices that should always be adopted to prevent spread of diseases - should be exercised when handling raw meat from healthy animals.

Meat from sick pigs or pigs found dead should NEVER be eaten. Ill animals should be reported to the authorities and proper hygiene precautions and protection should be taken when destroying and disposing of sick or dead pigs.

The Department of Agriculture and the Department of Health in the Philippines are advising consumers to purchase meat ONLY from meat stalls who are certified by the National Meat Inspection Service of the Department of Agriculture.

As a precaution, anyone who is slaughtering or preparing pigs from the area where pigs are known to have been infected, should take proper precautions, such as wearing gloves, goggles and other protective gear. Children and those not involved in the process of slaughtering should be kept at a distance (several meters).

Is meat from the affected areas available to the public?

WHO and the Philippine Government are advising the public to purchase pork meat only from accredited sources and to report sick or dead animal to the authorities.

Can the Ebola Reston viruses survive in meat?

Yes. Ebola Reston-like viruses survive in contaminated raw meat and therefore could be spread through the marketing and distribution of contaminated food products, such as fresh or frozen meat. We are uncertain of the risk to humans but we do know that cooking pork until there is no pink in the meat will kill viruses.

Could Ebola Reston viruses survive in frozen raw meat?

Yes. We do not know if this virus poses a risk to humans, therefore we recommend people use good hand hygiene, hand washing and usual disinfection practices to handle and prepare frozen raw meat.

Is it possible to identify infected meat?

Like any other viruses and microorganisms, Reston Ebola is not visible in meat. The only way to identify it would be through laboratory testing.

What are the standard hygienic handling practices?

1. Separate raw meat from cooked or ready-to-eat foods to avoid contamination. Do not use the same chopping board or the same knife for raw meat and other foods. Do not handle both raw and cooked foods without washing your hands in between and do not place cooked meat back on the same plate or surface it was on before cooking.

2. Keep clean and wash your hands. After handling frozen or thawed raw pork meat or pork products, wash your hands thoroughly with soap. Wash and disinfect using normal household disinfectants (note that the Reston virus – like many viruses - is easily inactivated by heat and household detergents) all surfaces and utensils that have been in contact with the raw meat.

3. Cook thoroughly. Thorough cooking of pork meat will inactivate the virus. Either ensure that the pork meat reaches 70 °C at the centre of the product ("piping" hot) or that the meat is not pink in any part.

Is there an effective vaccine against Ebola Reston virus?

No, there are no vaccines for humans or for animals against Ebola Reston virus.

How does this virus spread between animals?

The predominant mode of spread between non-humans is far from certain. We do know that transmission between monkeys is by direct contact with infected bodily secretions and possibly by aerosol. Transmission in pigs in currently being studied.

In Africa, Ebola infections of humans were linked to contact with gorillas, chimpanzees, monkeys, forest antelopes and fruit bats found dead or sick in the rainforest. Presence of Ebola virus nucleotide sequences in three fruit bat species from the Pteropodidae family seems to indicate that they play a role in the transmission of the virus and may play a role as asymptomatic carriers. This means that fruit bats may shed virus in various body fluids (saliva, urine, faeces, etc.) that can then come into contact with other animals, either directly or through contaminated food (e.g. fruits) that is eaten. Direct contact with a sick/dead animal could also be a way of transmission.

Does Ebola Reston cause disease in pigs?

Pigs can become infected but it is not known if they can become ill. It cannot be ruled out that other microbes or viruses, such as PRRS, may have caused illness and fatalities on the farms where the Reston Ebola infected pigs were bred and raised. The FAO is hopeful that appropriate laboratory tools can soon be developed to test swine and other animals throughout the Philippines. This will enable the FAO and the Philippines Department of Agriculture to determine how extensive the Ebola Reston infection is, whether Ebola Reston virus is still present in the pig population. The Philippines Department of Agriculture in collaboration with international partners is also planning to undertake laboratory experimental inoculation of pigs to evaluate if Ebola Reston can cause disease in pigs under laboratory conditions.

What is Porcine Reproductive and Respiratory Syndrome, or PRRS?

Porcine reproductive and respiratory syndrome (PRRS) is an infectious viral disease of swine that is easily transmitted through direct contact to susceptible pigs and also to foetuses. PRRS is also called also known as Mystery Swine Disease, Blue Ear Disease, Porcine Endemic Abortion and Respiratory Syndrome (PEARS) and Swine Infertility Respiratory Syndrome (SIRS). PRRS is characterized by reproductive failure in sows and respiratory distress in piglets and fattening pigs, and its potential for rapid spread.

PRRS is not a zoonosis, there are no records of humans contracting PRRS.

For more information, please refer to the Food and Agriculture Organization (www.fao.org)

Is there an effective vaccine against PRRS infection in pigs?

Yes. Vaccination has been shown to be effective in reducing PRRS infection in pigs.

How is WHO involved in this event in the Philippines?

Since being informed in late November by the United Nations Food and Agriculture Organization (FAO) WHO has been working closely with the Philippines Government to provide technical assistance and advice on the investigation.

The WHO is pleased with the level of collaboration with the Department of Agriculture and the Department of Health and their willingness to engage with international partners and to fulfill their international reporting obligations.

What to remember

· Reston species can infect humans but no serious illness or death in humans has been reported to date

· Investigations are ongoing and more information may be available in the near future

· Meat from healthy pigs is safe to eat IF it is handled and cooked properly

· Meat from sick or found dead animals should NEVER be eaten

· Meat should ONLY be purchased from certified stalls

· The standard five key food safety actions should ALWAYS be followed