Another Non-respiratory Bird Flu Fatality in Vietnam?
Recombinomics Commentary
February 27, 2005
>> Le Thi Sang lost her two daughters and a son during last year's outbreak after the family served 66 pounds of chicken at her son's wedding. Despite her loss, Sang still buys poultry a couple times a week and insists her children were not infected with avian influenza.
"My son and daughter died of pneumonia, while the other daughter died of stomach" bleeding, Sang, 58, insisted. "It's not bird flu." <<
The above comments suggest that more bird flu cases may present as non-respiratory cases. In this instance, the patient was tested for bird flu because she was in a cluster. This Thai Binh cluster is frequently cited as an example of human to human transmission in Vietnam and was one of the most widely publicized clusters.
The wedding was over a year ago and the groom developed bird flu symptoms January 3, 2004. He was a teacher and had no history of bird exposure. He was not tested, but died with bird flu symptoms. When his two sisters developed symptoms on the same day after caring for him, they were hospitalized and tested. Although initial tests were inconclusive, they were eventually confirmed to be H5N1 positive, and both died on the same day. One of the sisters had no history of contact with birds, which made human-to-human transmission more likely. Her mother however says she died of stomach bleeding, a frequent symptom of 1918 pandemic influenza. If she was not in the familial cluster, any testing for bird flu would have been unlikely.
Thus, this cluster has the common characteristics of the other 10 clusters. The disease onset is bimodal. One or two family members develop symptoms and 1-2 weeks later additional family members develop symptoms and test positive fro H5N1. However, the testing is frequently negative or inconclusive initially. Many clusters are not official clusters because there was no testing of the index case.
The bimodal distribution of disease onset suggests that all or most of these clusters involve human-to-human transmission between the family members. These cases represent over one third of all reported cases of H5N1 avian influenza in Vietnam, Thailand, and Cambodia.
The mother's comment on stomach bleeding as the cause of her second daughter's death suggests that many more cases of H5N1 were missed because the patient did not initially present with respiratory illness, and therefore was not tested for avian influenza.
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