Acute Neurological Syndrome, Unspecified, Bangladesh

Event ID: 2007-E-2889 ; Country: Bangladesh
Disease: Acute Neurological Syndrome, unspecified
Date: 22 November 2007; Type: GOARN update ; Classification: Restricted

Details: Update on field investigation and response, request for technical advice and assistance

Since 2 November, over a 100 cases, including 21 deaths, due to an outbreak of an unknown illness have been reported in Guainghat and Companyganj upazila within the Sylhet district of Bangladesh.

The major symptoms are rapid onset in previously healthy persons of diarrhoea, weakness and upper abdominal discomfort, followed by unconsciousness or impaired consciousness, severe nausea and vomiting, and in some cases, mild fever. Death has occurred within 24- 48 hours of the onset of symptoms. Some of the cases showed evidence of liver impairment such as raised ALT and jaundice. The majority of cases and deaths are in children.The date of onset of the most recent case was 13 November. At present, no suspected patients remain in hospital.

Field investigation and response:

On 5 November a national Rapid Response Team and senior staff were deployed to investigate the outbreak in the affected area. Dhaka Medical University has established a crisis committee to provide oversight for the outbreak investigations. The Bangladesh International Epidemiology Research Centre, South Asian Clinical Toxicology Research Collaboration (SACTRC), and International Centre for Diarrhoeal Disease Research, Bangladesh (ICDDRB) and the US Center for Disease Control (CDC) are supporting the investigations.

The Bangladeshi Ministry of Health (MoH) issued a request for technical support to WHO on 13 November. In response, a high level team of experts including an epidemiologist and a botanist were deployed by WHO/SEARO to the field to further investigate the outbreak.

Initial tentative diagnoses have included food poisoning, Japanese Encephalitis or Hepato-renal Syndrome caused by liver disease. Tests for Malaria, Nipah virus, Influenza A and B, and for Japanese Encephalitis (JE) are all negative. Hepatoencephalopathy from a toxic substance is the current hypothesis.

Particular attention is being paid to a wild leafy vegetable provisionally identified as Xanthium Strumarium. According to some reports it is consumed in the area and local customs attribute medicinal properties to the plant. Case control studies are being designed to investigate the plant or the possibility of some substance on the plant or use in its preparation that would explain the ongoing morbidity.

WHO/SEARO has been in contact with regional technical institutions, including Mahidol University, Chulalongkorn University, and Sirirat Hospital to identify additional support. The Department of Public health and environment (PHE) at WHO HQ is coordinating international support to the MoH.

Request for assistance:

The GOARN Operational Support Team has been asked to seek the further support of additional technical partners in the network:

• To identify an experienced clinical/toxicologist to be deployed to support the field team.
• To identify further subject matter expertise within GOARN institution to provide technical advice to the Bangladeshi
   health authorities and review information from the field.

Please provide details of experts available for rapid deployment to the field, and/or to provide technical advice and support to goarn@who.int.

GOARN Operational Support Team