Just over a month ago we learned of the deaths of two young siblings on the island of Bali from the H5N1 virus (see Bird Flu Claims Two Lives On Bali).
A week later, their mother (who had previously tested negative for the virus) was briefly hospitalized, but left the hospital against medical advice.
She died within 24 hours at home. For details see here.
Although the H5N1 bird flu virus was strongly suspected in the mother’s death, up until now we’ve had no official confirmation of that fact.
Today, Depkes – the Indonesian Ministry of Health – has posted an announcement (curiously back dated to Nov. 3rd) announcing that lab tests confirmed the mother died from the virus as well.
Ida at BFIC has a translation for us.
Posted by Ida on November 14, 2011
Indonesia Ministry of Health, the General Directorate of Infectious Disease and Environmental Health, through the National Institute of Health Research & Development laboratory, confirmed an additional H5N1 case in human.
Victim is a 29-year-old female with initial NP, resident of Bangli regency, Bali province. She is a mother of 2 former H5N1 cases (5-year-old female, and 10.5-year-old male).
Victim felt weakness, coughing and breathing difficulty on 15 Oct 2011, and sought for help to an emergency unit in nearby regional hospital. While she was about to be transferred to referral hospital, victim escaped and was found in a place of alternative healer on the next day.
Her condition was getting worse and died in her house on 17 Oct.
Epidemiological investigation showed that victim lived in area where many people rearing poultries. Also, large number of poultries belong to victim’s family and their neighbors died recently.
The details of epidemiological investigations out of Indonesia often read as if they were part of the same boilerplate press release; almost always pointing to possible contact with sick or dying poultry in the neighborhood.
While 8-days between the first child’s death and the mother’s is consistent with secondary transmission of the virus, it alone does not constitute proof.
The mother was treated with antivirals after her children were hospitalized, which might have delayed the onset of her illness.
It is also possible that she was infected at a later date by the same source (ie. neighborhood chickens) as were the children.
Despite the suspicious circumstances surrounding this cluster, proving H-2-H (human to human) transmission is always difficult, even with rigorous investigation. Frankly, if any other plausible explanation is available, it is usually embraced by the MOH.
As we’ve seen in the past, clusters in Indonesia often involve blood relatives, suggesting some sort of inheritable trait may affect susceptibility to the H5N1 virus (see Host Genetic Susceptibility to Avian Influenza).
But regardless of the manner in which this cluster evolved, it appears to have died out with these three victims. No epidemiologically linked cases have been reported on the island since then.
Although we continue to see isolated human infections around the world, and the virus continues to evolve (see H5N1: An Increasingly Complex Family Tree), for now H5N1 is primarily a threat to poultry.
The concern, of course, is that over time that could change.
For more on the potential for the H5N1 virus to adapt to humans, you may wish to revisit a couple of these recent blogs.