Under-Reporting of Bird Flu in Indonesia
Recombinomics Commentary
March 17, 2005
>> Indonesia sent its last follow-up report, No. 7, to the OIE on 10
Mar 2005, indicating H5N1 outbreaks in 2 districts -- Wajo and
Soppeng -- in the Sulawesi Selatan Province. According to the report,
the disease, affecting native chicken layers and broilers, was
introduced by illegal movement of animals from neighboring countries
(imported fighting cocks).
Official information on the situation in West Java will help.
According to the previous follow-up report, 6 Oct 2004, the outbreaks
were in East and central Java <<
Although the latest OIE report from Indonesia does have some information, it is significantly under-reporting H5N1 and H7N1 outbreaks described in a series of media reports this year. Indonesia's reporting record on HPAI is less than ideal. Last season there were media reports at the beginning of 2004 on dead chickens. Initially the government denied that the deaths were due to H5N1. Newcastle Disease was frequently cited. At the end of January the H5N1 outbreaks were acknowledged and the February 2, 2004 report indicated that H5N1 infections were widespread. The report indicated initial detection was December 15, 2003 and it summarized 127 outbreaks. Three provinces, Central Java, East Java, and Bali had over 25 outbreaks each. In the 127 outbreaks there were 4,700,000 poultry deaths. There were another 1,500,000 deaths reported in the March 5 report and 800,000 deaths in the April 9 report. The last report (October 8, 2004), prior to the most recent report, described 810 deaths in 2 districts.
Sequences deposited at GenBank clearly identified Indonesia isolates from chickens in 2003 (A/Ck/Indonesia/PA/2003(H5N1), A/Ck/Indonesia/BL/2003(H5N1), A/Ck/Indonesia/2A/2003(H5N1)) as well as early 2004 isolates (A/Dk/Indonesia/MS/2004(H5N1), A/Ck/Indonesia/4/2004(H5N1), A/Ck/Indonesia/5/2004(H5N1)). The sequences were clearly of the Z genotype, which is the same genotype found in the H5N1 isolates in Thailand and Vietnam. The only evidence that these isolates do not infect humans is the lack of such reports from Indonesia.
However, the latest OIE report clearly shows a significant under-reporting of H5N1 infections. The latest report describes H5N1 infections over a brief time period (February 27 - March 10). There are no numbers given on infected chickens. The infections are reportedly linked to movement of fighting cocks. Thus, the Indonesia OIE report implies that there was no H5N1 detected in Indonesia between October 8, 2004 and February 27, 2005.
These data are at odds with media reports, which detail H5N1 and H7N1 outbreaks during that time frame, including H5N1 spreading from Sulawesi to Mataram in December, 2004. The most recent media reports indicate that there have been outbreaks throughout 2005 involving deaths of 44,000 birds at very geographically distant locations involving 1.6 million sick birds.
The under-reporting or lack of reporting in Indonesia seems to be growing in frequency throughout the region. Vietnam has just recently started sending reports to the WHO. Media reports in the south on human cases abruptly stopped just prior to the Tet Lunar New Year on February 9. Re-testing at NIID in Tokyo indicates that the PCR test in the south only detects 20% of H5N1 infected patients, and repeated false negatives in the north also suggests similar under-reporting there. The failure of Thailand to detect any human cases this season also strongly suggests that their tests lack sensitivity.
Thus, as the number of familial clusters increase in Vietnam, with associated human-to-human transmissions to family members and health care workers, negative data is used to control the spread of confirmed H5N1 cases, as the spread of H5N1 increases.
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