Flu Stories: Indonesian Cluster of Human H5N1

by DemFromCT

Among the purposes of influenza surveillance is to pick up on human cases of H5N1, intestigate rumors, assess the situation and put news in context. Right now, all of that is being done in Indonesia, where there is a family cluster of cases. Eight people have been diagnosed with H5N1, 4 of whom have died (and possibly a fifth case as as well).

All eight cases were from the same family. Four members of the family have died from what health officials suspect could be bird flu, said WHO spokeswoman Sari Setiogi.

Blood samples have been sent to a WHO lab in Hong Kong for analysis, Setiogi said.

The family lived in a village in the Tanah Karo district in north Sumatra.

Indonesia's death toll from the H5N1 bird flu strain stands at 25 -- the world's second-highest toll after Vietnam, according to reports from The Associated. Press.

Several fatalities were members of the same family or lived near each other.

We are following this closely, as is WHO and CDC.

Clusters have been reported before. From Flu Wiki's cluster page:

Clusters of H5N1 infections are important because they may indicate human to human transmission of H5N1 influenza. Alternatively, they may simply indicate common exposure to the virus from an environmental source, presumably avian. A cluster here is defined as two or more individuals: 1. who are in close physical contact, 2. who become very sick with a respiratory disease, and 3. at least one of whom is a confirmed H5N1 influenza case. This is a relatively liberal definition of a cluster. It is left to the reader to evaluate the significance of the information presented here.

When such a group is brought to the attention of WHO, a team of epidemiologists is sent to look at the cases, and field studies are done to try and determine what the exposure is. From one of the ProMED moderators (ProMED is the listserv for the International Society for Infectious Diseases):

[Indonesia has continued to have cases of influenza A H5N1, some in
clusters, and these cases are likely to be confirmed.  As in earlier
clusters, the likelihood is that these cases share a common exposure
rather than representing person-to-person transmission. Map showing
the location of Medan in North Sumatra:
<http://www.un.org/Depts/Cartographic/map/profile/indonesi.pdf>
Further information including virologic confirmation and genetic
testing of the viruses is awaited.  - Mod.LM]

No reason for panic, but situations like this are why and how the internet can contribute; like breaking political stories, some of the first set of 'facts' turns out to be incomplete, untrue or smoke where there's fire. Separating that out is the job of the unsung heroes on the ground, some of whom leave the US and other countries on short notice just for that purpose.

While there's also some comfort in the relative quiescence of H5N1 elsewhere, the entire bird flu issue is a slow smoulder, not a flash fire at this point in time. Surveillance and precautions still need to be kept up. The ABC movie may have little to do with reality, but clusters like the one in Indonesia always have the potential to be more (or less) than they appear.

This particular cluster, along with the continued appearance of H5N1 in Africa, are why people continue to follow the story.

Comments

[John Casper]

Thanks DemfromCT for keeping up with this stuff for us.

[DemFromCT]

John Casper, here's a human interest piece. One of the cluster family members keeps running away from the hospital, despite setting aguard on him. Maybe it's not a great idea (from their POV) to go to a hospital if all that happens is that you die.