Emerging & re-emerging bacterial pathogens in India.

In spite of major successes against infectious diseases in the 20th century, new infectious diseases have emerged and old ones re-emerged in recent decades in different parts of the world. A brief survey of emerging and re-emerging bacterial diseases of public health importance in India is presented in this paper. Plague re-appeared in two outbreaks in Maharashtra and Gujarat in 1994, indicating a breakdown of the public health measures that had prevented its occurrence for several decades. Leptospirosis appears to be on the increase in Kerala, Tamilnadu and the Andamans during the last 2 decades, probably due to increased farming and inadequate rodent control. It is suggested that melioidosis due to the soil organism Burkholderia pseudomallei may be prevalent in many parts of India, but is under-diagnosed and under-reported. Since 1991, a completely new choleragenic Vibrio cholerae, designated 0139 has emerged in southern India and spread to other parts of India and to neighbouring countries, setting in motion the 8th cholera pandemic. Animal anthrax is very common in many parts of India, but human anthrax is recognised in only certain limited locations. In the Chittoor and North Arcot districts, its prevalence had increased in recent years. Since 1990, a multi-drug resistant variety of typhoid fever had been prevalent in many parts of India, caused by Salmonella typhi resistant to chloramphenicol, ampicillin and trimethoprim-sulphamethoxazole. Nosocomial methicillin-resistant Staphylococcus aureus infection seems to be widely prevalent in hospitals in many regions in India, and its prevalence seems to be on the rise. These pathogens pose new threats to public health, and call for appropriate responses. Microbiological expertise and epidemiological surveillance are deficient in the health care and public health systems in India; therefore even infections and diseases that have been under control elsewhere remain prevalent in the country, but are also under-diagnosed and under-reported. Without improving microbiological expertise and application as well as epidemiological skills and practices, emerging and re-emerging diseases may not be recognised, identified or intercepted in their early stages.