Does H1N1 pose risk to pigs?

Does H1N1 pose risk to pigs? Tests show it’s not yet in U.S., but the industry is at risk from sick people. By Ed Clark Editor’s note: The following three reports are based on presentations at the World Pork Expo in Des Moines, Iowa, USA, in early June. Thus far, the new H1N1 virus

Clark

July 6, 2009

Editor’s note: The following three reports are based on presentations at the World Pork Expo in Des Moines, Iowa, USA, in early June.

Thus far, the new H1N1 virus has not been discovered in any U.S. pig, but that doesn’t mean hogs are safe from it “That is the question, isn’t it?” Dr. Gregory Stevenson, Iowa State University professor and researcher, said at the World Pork Expo in early June.

“We have to ask at risk in what way,” Stevenson said.

“I think the industry’s at risk potentially in two ways. H1N1 is not considered by the swine industry to be one of the major diseases as compared to PCVC2 or PRRS virus. In regard to the economic question, I think we all realize that if the virus gets in our herds, there are potentially a lot of repercussions.”

At this point, however, there was a study conducted where Iowa State University Veterinary Diagnostic Laboratory scientists took 125 H1N1 viruses of the last six months that represented all the geographic regions of state. They took the M and NA genes, which are the unique genes in this new virus, and sequenced them in their entirety. The scientists compared them to the new virus as well as standard endemic viruses in swine and found that all of the viruses found and were isolated “were those that we’ve had for many years,” Stevenson said.

The unique virus, the H1N1 virus that has been in people recently is not “in any of our Iowa swine and this has been the case with laboratories that have done similar studies, so as far as we know to this date, it is not in our swine population.”

People pose largest risk

The biggest risk to pigs of the H1N1 virus outbreak that emerged in Mexico on April 24 is people, Stevenson said. One of the biggest factors potentially increasing the risk to pigs is whether the new human form of H1N1 becomes well established in the human population this fall. If it does, the risk posed to pigs would be workers who come to work sick, he said.

North American swine are endemically infected with a different H1N1 than the recent human form, as well as H1N2 and H3N2, Stevenson said.

“Of these, testing at the ISUVDL has consistently demonstrated H1N1 to be the most common.” Yet, he said, in testing at the lab through the first quarter of 2009, the overall proportion of swine respiratory disease submissions in which swine influenza virus (SIV) has been demonstrated has decreased (see chart).

Stevenson said that while an H1N1 virus was isolated from diseased people in Mexico and rapidly spread around the world, its source remains unknown. This H1N1 flu outbreak virus (H1N1FOV), as it is now know, is composed of six genes that are like those in the common endemic North American swine H1N1 virus. However, the remaining two genes are like those in endemic influenza viruses infecting European and Asian swine. These genes are the NA gene and the matrix (M) gene, Stevenson said.

This virus likely emerged by an event termed “antigenic shift.” In antigenic shift, two different influenza viruses infect the same host at the same time. During viral replication in the host’s cells, the genes from each virus can be mixed such that a progeny virus can derive some of its eight genes from each parent. “Like each of us, this progeny virus then expresses characteristics derived from the genetic material of each parent. In reality, these progeny viruses do not often survive and become established in populations,” he said.

Antigenic shift

In the case of H1N1FOV, it was immediately assumed that this antigenic shift occurred in pigs, because all genetic components of the virus are of swine origin. It was also assumed that pigs transmitted the virus to people in Mexico. However, to date, the H1N1FOV virus has not been discovered endemically infecting any pigs in Mexico or anywhere else in North America. There has been one discovery of H1N1 infection in pigs in Canada where H1N1-infected people from Mexico likely infected the pigs.

Recently, a new test based on a unique region of the M protein in the H1N1FOV has been developed by ISUVDL. “Just this past week we got a test that we don’t believe will give false positives,” Stevenson said. This test will detect and identify only H1N1FOV and will test negative for all know endemic North American swine influenza viruses.

Stevenson noted that the U.S. Department of Agriculture will soon launch a pilot surveillance program in cooperation with officials in individual states for swine influenza virus in pigs in the United States. Officials in Iowa are finalizing details for the program, including the involvement of the ISUVDL where samples will be tested.

The programs will be composed of three surveillance streams, 1) swine that are epidemiologically linked to a human case of the H1N1FOV, 2) swine observed with influenza-like illness at first points of concentration, i.e., exhibitions, fairs and sale-barns, and 3) client authorized (voluntary) influenza-like illness submissions to the veterinary diagnostic laboratory. For the first two surveillance streams, state officials will collect samples and deliver them to the ISUVDL for standard influenza testing as well as for specific H1N1FOV testing. The third surveillance steam will be strictly voluntary. The specific H1N1FOV test will be only be on tissues from submissions in which the submitter has volunteered to participate by completing a written authorization prior to testing.

There has not yet been a statement by USDA on what the agency will do if H1N1FOV is found in pigs, Stevenson said. “I’ve heard rumours, but I’m not going to share those with you.”

No profits for pork until 2010

Were it not for the impact of the H1N1 virus, U.S. pork producers would be about break-even right now. But because of the drop in demand due to the wrongly named virus, it will likely be well into 2010 before producers see any black ink, Glenn Grimes, University of Missouri economist, said at a market outlook session at the World Pork Expo June 3, in Des Moines, Iowa. Producers have been losing money since 2007, one of the longest periods of losses in recent history.

“No question, at the time when we should have had a rally in prices (this spring), we had really had news. Grimes estimates the total losses from H1N1 during May to be $113 million and $141 million in June. Total losses to U.S. producers from the virus outbreak through August may be as much as $500 million.

Yet despite two years of losses, sow numbers have not yet been reduced to bring supply and demand into balance. “We have to downsize and we have to downsize substantially,” Grimes said. The only producers making any money, he said, are those who locked in futures prices at levels above $70/head, which was possible prior to the outbreak of H1N1 April 24. For the first time in the past 20 months, futures markets gave producers to opportunity to lock in profits, both with higher hog price expectations, and lower feed prices earlier in the year. Both the outlook for both has now changed.

On March 1, the U.S. breeding herd was down slightly from the previous year. “But we have to be down a minimum of 5%, maybe 10%,” he said. In addition, he said, hog weights have been increasing “at a time when we don’t need it.”

H1N1 notwithstanding, the losses of the past two years have not been due to weak demand, but rather to high oil prices, high ethanol demand, and as a result, high feed prices, which has meant “red ink. The problem of the past two years has not been demand, it’s been cost.” Going from $2/bu. corn to $4/bu corn means that “producers have to cut down the hog herd and we have not done that.” One reason why, he says, is continued increases in productivity, which has been improving at a rate of about 2% per year.

Through March, demand for pork in 2008 had been in positive territory, similar to poultry, while beef demand had been a negative, he said.

From 1980 to 2008, pigs per litter have increased from 7.5 to 9.5, litters per sow per year have increased from 1.6 to 2.2, and pigs per sow per year have increased from 13-14 in 1980 to above 20 in 2008. “These are dramatic changes,” Grimes said.

The bright spot for the industry the past two years has been pork exports, he said. Last year saw a 6% to 7% increase in demand for U.S. hogs, “and most of that was exports.” In 2008, U.S. exports were up 46.6% from the previous year, but are expected to decline 13.2% this year, Grimes said. European Union pork exports, meanwhile, were up 33.4% last year, but will likely decline by 27.1% this year.

High and volatile soya meal likely

Soybean meal prices (see chart) through early October are likely to remain “high and volatile, potentially explosive,” a leading U.S. grain marketing economist said at the World Pork Expo in Des Moines, Iowa, USA, June 3.

“Local shortages of soybean meal in August and September are as definitely possibility with the sharp drop in South America’s spring 2009 harvest,” said Dr. Robert Wisner, Iowa State University, USA, economist. 1 August anticipated soybean stocks of just 2.2 weeks supply versus 3.5 weeks in 2007-08 “is the tightest since at least 1965,” Wisner said. Likewise, maize prices are up 29 cents per bushel since “the April 20 break-out,” on weather concerns. One report suggests that about 1 million less 2009 corn planted acres, due to late plantings in the Eastern Corn Belt, Wisner noted.

China imports wild card

One “wild card” in soybean meal prices is that 56 million bushels of old crop bean export orders to China have not been shipped and that could be added to new crop meal exports, which would add pressure to prices. Wisner expects soybean meal prices to average $425/ton this year. “There is a sharp drop in soybean crush, exports are coming up, and China is stocking up on soybeans.”

Wisner sees “a little relief” in soybean meal prices for livestock producers in 2010, however, when he looks for meal to average $280/ton.

The economist looks for maize prices to average $4.25/bu., but with yield problems, prices could go over $5/bu. On 29 May, July maize futures on the Chicago Board of Trade were $4.36/bu., with December futures of $4.58.

Several factors are combining to drive feed prices higher. The first is delayed planting of maize acres in the U.S. Midwest. He expected some of those acres to shift into other crops, and some not to be planted at all.

A second factor, he said, is the huge drop in South American crops that will boost exports of U.S. feed. China, he said, will shift some of its purchases from South America to the United States. In its 12 May report, the U.S. Department of Agriculture estimated total South American maize crop prospects to be down 675 million bushels from 2008 levels, with soybean production down 711 million bushels.

Decline in wheat supplies

And the third factor is the decline in feed wheat supplies, which has been a competitor to maize. He added that one additional factor adding pressure to crop prices is a return of commodity investment funds in futures prices worth watching. Wisner said that weather trouble spots are dry weather in the heart of the key corn/soybean production area in China, and frost on the wheat crop and dry weather in Canada.

For the current crop year, delayed U.S. planting will likely mean yields below trend. In addition, he looks for a sharp increase in ethanol demand from mandates in energy bill passed by the U.S. Congress, with increases in biofuel production overall. “Biofuel mandates will be enforced next year,” he said. “Biofuels mandates are on a collision course with greenhouse gas emission regulations and allowable ethanol blend levels,” Wisner said.

The only decline in demand he sees is coming from reduced U.S. livestock numbers.

Looking at the general economy, Wisner looks for three trends: a weaker dollar longer term; increasing inflation beginning in mid 2009; and higher interest rates beginning mid-2010. Wisner does not see a recovery in the world economy until at least the first quarter 2010. He looks for crude oil prices in the $55-65 level through 2009, then gradually increasing into 2011. This will increase ethanol prices, and when combined with higher government mandates, increase demand for corn. “Higher gasoline and ethanol prices reinforce corn price strength potential with weather concerns.”

Wisner sees four types of possible economic recoveries: a V-shape, the sharp decline followed by a sharply higher recovery, a scenario looking less likely; a W-shape, or temporary recover; a U-shape or gradual recovery; and an L-shape, extended period of stagnation (with inflation). The latter can’t be ruled out with cap-and-trade legislation, Wisner said.

He gives a U.S. cap and trade bill on greenhouse gases a 50-50% chance of passage by Congress, which would increase energy costs. If the U.S. government mandates the use of E-15 ethanol (gasoline containing 15% ethanol), thus increasing ethanol demand, maize used for ethanol could increase by 43% to 45%. At present, he said, the ethanol industry is just covering its costs if plants have been buying maize in the spot market. But plants that contracted maize last year at higher prices are losing money, and that’s been the cause of recent bankruptcies.—Ed Clark

Wisner’s entire presentation is available online.