In the village of Kubu Sembelang, Karo District, North Sumatra, Indonesia, six people in one extended family have died of avian flu, and it may be that they passed the disease from one person to another, instead of getting it directly from birds around them. At first glance it sounds a bit worrisome, and the World Health Organization is sending in a team to keep an eye on things. But they have not raised their alert level. And our Medical Unit, which provides a very valuable service by polling experts in their fields, got a series of responses after this story broke yesterday, which mostly have one theme: don’t panic. Take a breath. We don’t know enough. Seven cases, all several weeks ago, do not make a pandemic. (Transmission electron micrograph of Avian influenza A H5N1 viruses (shown in gold). Image credit: CDC.) This from Dr. David S. Fedson, a past member of the Pandemic Influenza Task Force at the Infectious Diseases Society of America: "The first case(s) in this family cluster arose in late April, more than three weeks ago. If the virus that has affected this family had been a true pandemic virus, it would have spread throughout the neighborhood, into the community and into adjacent and even far-distant communities. The absence of such spread, together with the genetic sequencing data, clearly indicates that this virus is not the harbinger of the next pandemic. Stick around, though; another virus could be waiting in the wings." Dr. Frank James of the University of Washington, Seattle: "This [is] exactly what a pandemic will look like when it starts but this does not appear to be that event given that the virus was sequenced by two labs and found to be unchanged genetically. Likely the cluster is just due to the close proximity of cases, as has been the case in other clusters." Dr. Richard Olds of the Medical College of Wisconsin: "Concerning, but not yet a reason to panic. First of all, the investigation is ongoing and it sounds like all the cases are in a small town where it will be difficult to rule out direct environmental exposure. Remember that bird manure was the purported source. Even if direct transmission…took place, it may not have any clinical relevance if there are no subsequent cases." And this late response from Dick Thompson, press officer for the World Health Organization in Jakarta: "There is concern. There was an ‘obvious human-to-human transmission’ documented in China in NEJM. We need to determine as quickly as we can whether there was a change in the virus itself. If so, the response would be to contain it, contact tracing, and keeping people from passing it on. Yet this strain is no different from others found in the region." All this leaves us in a position nobody ever likes, with incomplete information from far away. But Dr. James was asked by e-mail, "Are you concerned?" His answer: "No." We have a lot of background informaton HERE. And our latest update is HERE. ———– Update, 5 PM EDT Dr. Julie Gerberding, head of the Centers for Disease Control, just held a teleconference for reporters asking about the outbreak. Some comments: "We don’t have any alarm bells going off in terms of an indicator of a more virulent form of the virus, or an impending pandemic. Nevertheless, every time there’s a clustered outbreak we take it very seriously …."
"It’s a very, very sad situation for the families that are affected, but we also appreciate that so far, we are not seeing anything that suggests a pattern that’s different from the patterns we’ve seen anywhere else in Asia up to this point in time." She also said:
–There has been "no community spread" through the village beyond the family that was affected.
–There is no evidence the virus has evolved. There is no apparent change in the way the virus binds to parts of the respiratory tract.
–The virus appears to be "susceptible to Tamiflu"–a good sign, she said, if ever the virus were to mutate to a form that easily spread from one person to another. She added that it’s not even entirely clear that the deaths were caused by the H5N1 virus. There is also Influenza B in the region.