Anthrax meningoencephalitis--declining trends in an uncommon but catastrophic CNS infection in rural Tamil Nadu, South India

Abstract

Introduction: Anthrax, a cattle-born zoonosis has been a serious infectious disease and its meningoencephalitic form remains a rapidly fatal illness even now.

Aim: The aim of this paper is to evaluate the incidence and clinical profile of anthrax meningoencephalitis admitted to a teaching hospital predominantly serving a rural population in South India.

Materials and methods: We made a systematic study of the case records of patients with microbiologically confirmed diagnosis of anthrax meningoencephalitis admitted over a 20-year period. We searched the internet and office records for the anthrax outbreaks and the preventive strategies in place in India.

Results: The admissions occurred in two clusters, four during 1992-1994 and six in 1998-2000; with no further detection unto August 2008. All patients were adult males with agriculture related occupation. Three of the 10 patients had no evidence of primary focus of infection. Majority were in coma at admission and had documented evidence of septicemia. CSF was haemorrhagic and death was the uniform outcome despite high dose intravenous penicillin G; maximum duration of hospital survival being 48 h.

Comment: Anthrax is a rare, but catastrophic cause of meningoencephalitis. Improvement in education and life styles as well as livestock vaccination in rural areas appear to have effectively decreased the incidence of this dreaded acute zoonosis in the South Indian states of Tamilnadu and Puducherry.