ABSTRACT
Background: Outbreaks of streptococcal pneumonia among young recruits in military training centers are welldocumented. A signifi cant outbreak of pneumonia occurred between November 19, 2011 and February 4, 2012 among the young recruits of a large training center located in Southern India. Objectives: The objective of this investigation was to identify the cause of the outbreak, to control the outbreak at the earliest, and to provide future strategies for containing such an outbreak. Materials and Methods: The outbreak was investigated using standard epidemiological methods so as to describe its epidemiology, to identify the causative organism, to guide the outbreak control efforts, and to provide future strategies for containing such an outbreak. Results: Over 2 months, 58 cases of pneumonia occurred among the recruits of the center, giving an attack rate of 4.81 cases per 1,000 person-months. Radiological positivity was found in 72.4% of the cases. Streptococcus pneumoniae (S. pneumoniae) was grown in all the three bronchoalveolar lavage (BAL) samples. The outbreak rapidly ended following prophylaxis with oral azithromycin. Conclusions: This outbreak of pneumococcal disease occurred in the setting of intense military training and a crowded environment. Oral azithromycin was found to be the suitable strategy for control of the outbreak.
ABSTRACT
Background: Following a suspected outbreak of scrub typhus in Kurseong, Darjeeling, the Armed Forces Medical College, Pune was requested by the National Institute of Epidemiology and the State authorities to undertake investigation of the ongoing scrub typhus outbreak and suggest containment measures. Materials and Methods:The epidemic team undertook clinical, entomological and serological studies to understand the local disease pattern and delineate high risk areas, host diversity by rodent trapping using Sherman traps, mite fauna diversity, abundance and vector species identification by phase contrast microscopy for preparation of electronic database and rodent and human serological studies by Weil Felix and PCR. Results:The results indicate no association of scrub typhus with age and sex (P=0.37 and 0.74 respectively). The maximum cases occurred amongst the tea garden workers (73%) in the age group of 25-44 years. The predominant clinical presentation was fever (100%) with headache (75%), lymphadenopathy (45%) and presence of eschar (76.7%). The dominant host species (50% of trapped rodents) was shrew Suncus murinus, the index animal for scrub typhus, which contributed maximally to the vector abundance (52.96%) with a chigger index of 61.56. The trombiculid mite Schoengastiella ligula was the vector species much against the expected mite vector Leptotrombidium deliense, in the area. The study found the presence and abundance of vector species which corroborated well with the occurrence of cases in the various localities within the subdivisions. Conclusion:The study thus establishes Schoengastiella ligula as the vector of scrub typhus outbreak in Kurseong, Darjeeling. Preventive and containment measures with emphasis on reduction of man - vector contact were suggested to the state authorities to contain the outbreak.