Dec 9, 2010
Indonesia reports H5N1 infection
Indonesia’s health ministry reported an H5N1 avian influenza infection in a 21-year-old woman from Bandung City in West Java province, according to a World Health Organization (WHO) statement today. She got sick on Nov 14 and has been hospitalized since Nov 22. Her illness raises the number of WHO-confirmed H5N1 cases in Indonesia to 171, of which 141 were fatal. An investigation into the source of her infection found that she lived near a business where live poultry were kept in unsanitary conditions. The WHO said more investigations into her illness are under way. The woman's infection raises the global number of H5N1 infections to 510, including 303 deaths.
Dec 9 WHO statement
South Korea, Vietnam report H5N1 in birds
Veterinary authorities in South Korea have detected H5N1 avian flu in a mallard duck during surveillance in North Jeolla province, located in the southwestern part of the country, according to a report today from the World Organization for Animal Health (OIE). The duck was one of 39 wild birds that were captured and sampled during the surveillance activity. The source of the virus is unknown. South Korea's last H5N1 detection occurred in May 2008, when the virus struck poultry farms in several provinces. Meanwhile, Vietnam recently reported three H5N1 outbreaks in poultry, two in Nam Dinh province and one in Nghe An province, according to a Dec 4 OIE report. Both are in the northern part of the country. They began on Nov 18. The outbreaks sickened 244 birds, of which 172 died. The remaining 2,037 were culled to control the spread of the virus. Investigations suggested that the source of the outbreaks may have been the introduction of new birds into the flocks, illegal poultry movements, or fomites. The virus is considered endemic in Vietnam.
Dec 9 OIE report
Dec 4 OIE report
Researchers see original antigenic sin at work in dengue infections
Writing in the Journal of Virology, an international team of scientists reports finding "dramatic evidence of original antigenic sin" in dengue virus infections. The theory of original antigenic sin holds that the immune system's first encounter with a pathogen strongly shapes all subsequent responses to that pathogen, so that if the host later encounters a different strain, the immune response will be specific to the original strain and potentially less effective. In the study, a team from Britain, Thailand, and Vietnam note that there are four dengue virus serotypes, that infection with one type generally does not confer immunity to the other three, and that later infection with one of the other strains can lead to more severe disease. The team analyzed human antibody responses to domain 3 of the dengue envelope protein, or ED3. They found that a first infection triggers low-level antibody responses to ED3 and that these are "boosted dramatically" by a second infection with one of the other serotypes. They suggest that these antibodies bind to the secondary virus without neutralizing them and may instead actually worsen the infection. The researchers also report developing an enzyme-linked immunosorbent assay (ELISA) that can be used in secondary dengue infections to determine the serotype of the primary infection. They say their findings imply that any dengue vaccine will need to induce balanced responses against all four serotypes with the first dose.
January J Virol abstract
Report details paragonimiasis from raw or undercooked crayfish
A report today on nine patients who contracted the parasitic disease paragonimiaisis underscores the risk of eating raw or undercooked crayfish. The patients, from 10 to 32 years old and all but one male, ate crayfish while camping or canoeing on Missouri rivers from 2006 to 2010. Two to 16 weeks later they had fever and cough as well as pleural effusion (excess fluid surrounding the lungs) and eosinophilia, which is an increase in a type of white blood cell that signals a roundworm infection. Testing confirmed paragonimiasis, which is caused by Paragonimus trematodes, commonly known as lung flukes. Seven of 9 adults ate the crayfish after consuming alcohol, and 2 on a dare. The 10-year-old ate a small crayfish raw to demonstrate survival skills. In all patients, symptoms, eosinophilia, and x-ray abnormalities resolved 1 to 3 months after a 2- to 3-day course of praziquantel. The Food and Drug Administration advises cooking shellfish to an internal temperature of 145°F (63°C).
Dec 10 MMWR report
Kentucky reports sharp rise in pertussis cases
The Kentucky Department of Public Health is urging the state's residents to ensure that children receive their recommended pertussis vaccines and that people ages 11 to 64, especially those who have contact with children younger than 1, get a pertussis booster, the Lexington Herald-Leader reported today. The plea for pertussis vaccination comes amid a steep rise this year in pertussis cases. So far this year it has received reports of 250 cases, up from 47 in 2007.
Dec 9 Lexington Herald-Leader story