Evidence of Human H5N1 Transmission in Garut Cluster
Recombinomics Commentary
August 22, 2006
According to the Director General, 18 villagers Cikelet were it was suspected infected by bird flu.
Three among them namely U (17), the HOPE (9), and EL (35), was stated positive was infected by the virus H5N1 by the Body of Health Research And Development (Balitbangkes) the Department of the Health and NAMRU2 Jakarta.
Five other patients died before could be taken the sample of his blood to be checked.
The above translation indicates five Cikelet patients with bird flu symptoms died prior to collection of samples. These five deaths provide the evidence for human-to-human transmission of H5N1 bird flu. The latest WHO update acknowledges that there were deaths in late July and early August and the deaths included family members. Four of the five fatalities have been identified in local media reports, and three of the four identified are related to patients who tested positive.
This relationship, coupled with the disease onset dates, indicates there was human-to-human transmission in the Garut cluster. As the WHO noted in their prior commentary, the identical disease onset dates of two cousins made it unlikely that the two cousins infected each other. However, the sister of one of the cousins in among the patients that died prior to collection of samples, suggesting she may have infected her brother and cousin. Similarly, the daughter of another confirmed case was among the early cases who died before samples could be collected.
Thus, the gap in disease onset dates indicates the patients who died earlier infected the patients who tested positive later. Although the disease onset dates may not be available, the early dates for the deaths would also indicate there was human-to-human transmission.
The 10 additional suspect cases may not test positive because of Tamiflu treatment, The treatment can reduce H5N1 to levels that are not detected, creating false negatives. However, these patients may develop H5N1 antibodies, but those levels may not peak until 2-4 weeks after disease onset dates.
Thus, although the number of confirmed positives remains at three, the 5 earlier fatalities, coupled with 10 additional suspects cases, many of whom are related to the confirmed cases, provide evidence of human-to-human transmission in the Garut cluster.
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