Report of multicentre outbreak of Buffalopox virus infection in burn units, Karachi, Pakistan

Abstract number: 1733_1203

Mioulet V., Dowsett B., Easterbrook L., Hasan R., Zafar A., Swanepoel R., Hewson R., Nizam M., Ahmed A., Husain A., Grobbelaar A., Bewley K.

Objectives: Sporadic outbreaks of Buffalopox (BPV) and its transmission among farmers have been reported from the subcontinent. We describe the first multi-centre nosocomial outbreak of BPV infection amongst burns patients in a major city of Pakistan.

Method:Notification of outbreak: Atypical lesions involving burns wound were first noted in a patient at a burns unit in Karachi. Similar lesions rapidly affected other patients within this unit. During infection control investigation, patients with similar infections were being reported from other burns centres in the city. Investigation: Clinical specimens from the lesions were submitted for routine culture and for histopathology. Impression smears, material from the lesions and biopsy tissue were used for electron microscopy, DNA sequencing and in-vitro culture.

The epidemiological finding suggested a common origin of infection. To investigate this, practices at the affected burns units were observed and materials in common use for cleaning and dressing wounds at all the various centres were collected for testing.

Results: Clinical samples submitted for bacteriological and mycological culture proved negative. On histopathological examination no Molluscum bodies were found. Electron microscopy revealed the presence of orthopox virus particles. Examination of ultrathin sections of infected Vero cells demonstrated classic orthopox virus maturation with intracytoplasmic `virus factories'. Portions of the gene were sequenced and analysed. The resulting phylogenetic tree grouped the sample within the Buffalopox sequences. All surveillance was reported negative. Nevertheless, clinical samples submitted from several centres revealed the existence of the same pox virus.

To control nosocomial transmission in the units, a number of measures were taken including staff education, reinforcement of infection control practices and strict isolation measures which successfully controlled the disease spread within the primary unit.

Conclusion: We report first nosocomial outbreak of BPV infection among patients admitted to different burns units located significant distances apart. Initial investigation could not reveal the source but it is very likely that nosocomial transmission of the viral infection was due to frequent transfer of exposed patients between the different units. This hypothesis is supported by the fact that strict infection control measures in one unit succeeded in controlling transmission.

Session Details

Date: 31/03/2007
Time: 00:00-00:00
Session name: European Society of Clinical Microbiology and Infectious Diseases
Location: ICC, Munich, Germany
Presentation type:
Back to top