Summary of Selected Disease Events

April-June 2004

I. OIE Listed Diseases

Highly pathogenic avian Influenza in Asia

China:  The first outbreak of highly pathogenic avian influenza subtype H5N1 (HPAI) in the People's Republic of China (PRC) was confirmed in Guangxi Province on January 27, 2004.  The outbreak eventually involved 49 premises in 16 provinces.  No new outbreaks were reported in the PRC for 32 consecutive days prior to March 19, 2004, and movement restrictions were subsequently rescinded.  On July 6, 2004, China reported that HPAI had occurred again in late June on one farm in Anhui province.  As a result, China has resumed movement controls.

Indonesia:  Indonesia has had ongoing outbreaks of HPAI since January 2004.  In May 2004, new outbreaks were detected in four previously infected districts.  A total of 14 of 33 Indonesia provinces have HPAI activity.

Thailand:  Thailand reported 11 outbreaks of HPAI during March through June 2004.  In addition to depopulation, countrywide control measures underway include quarantine and restricted movement of poultry; vaccination is prohibited.  A total of 12 human cases and 8 deaths due to HPAI infection occurred in Thailand during the January-March 2004 outbreak, no new human cases have been reported since March 10, 2004.

Vietnam:  An outbreak of HPAI subtype H5 involving 5,000 birds was reported to OIE on June 29, 2004.  No human cases have been reported in Vietnam since February 18, 2004.

Note:  For additional information, please see the OIE website at http://www.oie.int/eng/en_index.htm.

Sources:  OIE, FAO

Avian Influenza in Canada

On March 9, 2004, Canada reported the detection of both low and high pathogenic forms of avian influenza virus subtype H7N3 on a farm in Fraser Valley, British Columbia and was the first reported occurrence of highly pathogenic avian influenza (HPAI) in Canada.  Due to rapid spread of the disease, on April 5 the Canadian Food Inspection Agency (CFIA) announced that commercial and backyard flocks in Fraser Valley would be depopulated.  By April 8, 20 commercial flocks had been infected and by May 25, HPAI had been confirmed in 42 commercial and 11 backyard flocks.  An estimated 19 million birds were depopulated by May 28.  Restocking began outside the high risk area on June 10, 2004.  The high risk area began restocking on July 9, 2004, 21 days after the last infected premises was cleaned and disinfected.  Official veterinary controls still prohibit the movement of hatching eggs and live poultry out of the control area, while federally graded table eggs and poultry meat may be moved out of the control area subject to official controls.  For more information, please see the CFIA website at http://www.inspection.gc.ca/english/toce.shtml.  CEI’s impact worksheet on HPAI in Canada can be accessed at http://www.aphis.usda.gov/vs/ceah/cei/worksheets.htm.

Sources:  Canadian Food Inspection Agency, CEI Impact Worksheet

Avian Influenza in the United States

Texas:   Avian influenza subtype H7N3 was detected in three chicken flocks in Hopkins County, northeastern Texas in May and June 2004.  Two commercial flocks, each with approximately 24,000 birds, were depopulated and buried during May 2004.  Intensive flock testing was conducted in commercial and noncommercial flocks within 10 miles of the index flock.  On June 22, 2004, a third flock of 14 birds was confirmed positive for H7N3 and depopulated.   Ongoing flock testing is expected to continue through the end of July.   For additional information, please see the Texas Animal Health Commission website at http://www.tahc.state.tx.us/ or the CEI website at http://www.aphis.usda.gov/vs/ceah/cei/worksheets.htm.

Source:  Texas Animal Health Commission

Vesicular Stomatitis, Texas, New Mexico and Colorado

Vesicular stomatitis (VS) was reported in southern Texas in May, 2004.  In June, additional cases were reported in Texas and New Mexico .  On July 7, 2004 , Colorado reported cases in two counties.  A total of 11 New Mexico premises have been quarantined due to VS in Cibola Eddy , Valencia , and Grant counties.  VS has been diagnosed in 3 Colorado horses in Las Animas and Douglas counties.  With the exception of infected cattle on two of the five quarantined premises in Starr County , all cases in Texas involve only horses.  Other cases in Texas have been confirmed on one premises each in Reeves, Uvalde, Dimmit, Yoakum and Val Verde counties.  Affected counties are indicated on map.  For additional information, please see the Texas Animal Health Commission website at http://www.tahc.state.tx.us/ or USDA, APHIS Hot Issues at http://www.aphis.usda.gov/lpa/issues/issues.html.

Source:  Texas Animal Health Commission

Foot and Mouth Disease, Brazil and Peru

An outbreak of foot and mouth disease (FMD) seroype O was reported to the OIE by Brazil on June 17, 2004 .  The outbreak occurred in the northern state of Para , where three of 130 cattle in one herd were found to be infected.  The affected premises is located in a relatively isolated area on the north bank of the Amazon river .  An epidemiologic investigation was initiated including surveillance for additional cases; as of July 2, 2004 , no new cases have been detected. 

Peru ’s Director General for Animal Health reported to the OIE an outbreak of FMD on June 17, 2004 .  Positive laboratory diagnosis of FMD type O was made on June 11 and 14, 2004 on samples taken from eight feeder cattle originating on three farms in the Lima Department.  A vaccination program had been in place in the affected area.  For additional information, please see the CEI website at http://www.aphis.usda.gov/vs/ceah/cei/worksheets.htm.

Sources:  OIE, CEI Impact Worksheet

II. Other Significant Disease Events

Porcine reproductive and respiratory syndrome, South Africa

Porcine reproductive and respiratory syndrome (PRRS) was reported from South Africa on June 18, 2004.  PPRS is a List B disease and not been reported before from South Africa.  One outbreak involving one farm of 2,500 swine was characterized by an abortion storm involving approximately 60 sows.  In response to the outbreak, vaccination, quarantine and movement restrictions have been imposed.  A provisional diagnosis of PPRS was made based on serologic testing (ELISA); confirmatory testing is underway.

Source:  OIE

Enterovirus infection resulting in paralysis, England

Enterovirus infection was determined to be the cause of illness in a two-year-old heifer from Cumbria that died after 5-6 days of paralysis in late 2003.  On June 21, 2004, an expert panel met to review the clinical and pathologic specimens for the heifer.  In addition, the panel reviewed an unrelated case in a bull, 20 sheep, and seven other adult cattle with similar neuropathological changes.  Testing for enteroviruses will be conducted for the remaining cattle and sheep.  The panel consisted of representatives from the fields of animal and human health including the Department of the Environment Food and Rural Affairs (DEFRA), Veterinary Laboratories Agency (VLA), the Department of Health, independent experts, and observers from the Food Standards Agency (FSA).  Louping ill, West Nile and bovine herpesvirus 1 had been previously ruled out based on diagnostic test results.

Source:  CDR Weekly (http://www.hpa.org.uk/cdr/pages/news.htm#meeting)

Spring viremia of carp, United States

Spring viremia of carp (SVC) was confirmed in Snohomish County, Washington on June 9, 2004 in koi housed in a backyard pond.  SVC is a viral disease that primarily affects species of cyprinid fish.  In response to the SVC finding in Washington, the remaining fish were culled and tested for SVC.  A traceback from the pet store where the fish were purchased is underway, but to date, no new cases have been found.  For additional information, please see http://www.aphis.usda.gov/vs/ceah/cei/worksheets.htm.

Sources: OIE, CEI Impact Worksheet

Taura Syndrome Virus, United States

Taura syndrome (TS) in farmed Pacific white shrimp (Litopenaeus vannamei) was confirmed in June, 2004 in Cameron and Willacy counties, Texas.  To date, a total of 5 facilities have been quarantined; among these 5 facilities, there are 170 ponds in production and 15 (8.8%) are infected.  TS has not been found outside Cameron and Willacy counties in the lower Texas coast.  Texas farmed shrimp operations along the upper Texas coast (north of Corpus Christi) and the West Texas operations have not been affected.  This was the second outbreak of TS in Texas; the

first outbreak occurred in farmed shrimp along the southern and central Texas Gulf coast in 1995.  The first reported occurrence of TS in the US was in Hawaii in 1994.  Please see the CEI website at http://www.aphis.usda.gov/vs/ceah/cei/worksheets.htm for additional information.

Sources: OIE, CEI Impact Worksheet

White spot disease, Hawaii

White spot disease (WSD) was confirmed in a single commercial shrimp production facility on the island of Kauai, Hawaii and the premises was quarantined on April 14, 2004.  The outbreak has been contained and restocking is underway, after disinfecting and drying ponds.  No virus has been detected outside the affected facility.  Prior to this outbreak, the only US reports of WSD had been off shore in the Gulf of Mexico and near shore in Texas, Mississippi, Georgia and South Carolina.  For additional information about this outbreak, please see the white spot disease impact worksheet at http://www.aphis.usda.gov/vs/ceah/cei/IW_2004_files/wsd_us_0404_files/wsd_us_0404.htm. 

Sources:  OIE, The Associated Press, CEI Impact Worksheet

Atypical scrapie, United Kingdom

The Department for the Environment, Food and Rural Affairs (DEFRA) has reported finding a sheep with a type of scrapie not previously seen in the United Kingdom.  Test results from several UK and European laboratories found that the case does not appear to resemble previously recognized cases of scrapie in the UK, and that it had some characteristics similar to experimental BSE in sheep and also to an experimental strain of sheep scrapie; however, experts concluded the case could not be considered to be BSE in sheep.  In June 2004, the UK tested the one millionth sheep for genotyping as part of the National Scrapie Plan (NSP).  The NSP was implemented in July 2001 to ultimately eradicate scrapie from the national flock through the identification and breeding of rams that are resistant to the disease.

Sources:  Department for Environment Food and Rural Affairs, ProMed

Nipah virus, Bangladesh

An outbreak of Nipah virus involving 30 persons including 18 deaths was reported to the World Health Organization in April 2004.  The outbreak occurred in the Faridpur District.  This is the second outbreak of Nipah virus infection in Bangladesh in 2004.  In January-February 2004, an outbreak of up to 70 persons, many of them children, occurred in a 5 district area, including Faridpur District.  During previous Nipah virus outbreaks, human cases occurred as a result of exposure to Nipah virus infected pigs.  Pigs did not appear to be involved in the January 2004 outbreak, and human cases are thought to have occurred through exposure to fruit partially eaten by fruit bats, the presumed reservoir of Nipah virus.

Sources:  World Health Organization, ProMed

This summary was produced in July 2004 by the Center for Emerging Issues, a part of USDA’s Veterinary Services.  This and other reports are available on the internet at: http://www.aphis.usda.gov/vs/ceah/cei/index.htm.  Comments or questions concerning this edition may be addressed to Kathy Orloski at kathy.a.orloski@aphis.usda.gov or 970-494-7221.