Apr 07, 2014
The agent that assists an effective control of vector born disease the ‘Trained Medical Entomologist’ is now on the verge of extinction, writes Deepak Saxena.
New Delhi: WHO has dedicated the theme of World Health Day- 2014 with a major focus on control of vector-borne diseases, “Small bite: Big threat”. VBDs causes a significant fraction of the global infectious disease burden. As per WHO more than half of the world's population is at risk from vector-borne diseases such as malaria and dengue.
In the past three decades, there has been dramatic global re-emergence of epidemic vector borne diseases. Vector-borne diseases are one of the greatest contributors to human mortality and morbidity in tropical settings including India. In India people suffer from a significant disease burden from these diseases in local and focal areas which is reflected in the form of morbidity and mortality from Malaria, Dengue, Chikungunya, Japanese Encephalitis (JE), Kala-azar and Lymphatic filariasis.
As per the country progress report of India towards attainment of MDG 6, the annual incidence rate (cases of malaria/1000 population) of Malaria has come down from 2.57 per thousand in 1990 to 1.10 per thousand in 2011, and to 0.88 cases (provisional) per 1000 population in 2012, reflecting that significant progress is being made across in combating some vector born diseases such as malaria and lymphatic filariasis but other diseases such as dengue, JE continue to spread at an alarming pace. Epidemic of Japanese encephalitis has become deadly in India, around 1500-4000 peoples are being affected every year. In year 2011, around 891 people, including 508 in Uttar Pradesh alone and 200 in Bihar, died due to encephalitis.
For learning the basics of disease transmission of any disease including vector born disease one needs to understand the Epidemiological Triad comprising of three corners (called vertices): Agent, or microbe that causes the disease (the “what” of the Triangle), Host, or organism harboring the disease (the “who” of the Triangle) and Environment, or those external factors that cause or allow disease transmission (the “where” of the Triangle). Last few years witnessed substantial improvement in various aspects of management of vector born diseases mainly preventive methods by insectidal residual spray, change in population behavior for using insecticide treated mosquito nets , new treatment modalities, new drugs and policies for management of vector born diseases, but vector born diseases still remain on top of public health concerns. Control of Vector born disease includes an in-depth understanding of vector bionomics, methods for vector control, source reduction and interpretation of indicators used to monitor the status of VBD at community and state level, but the agent that assists an effective control of vector born disease the “Trained Medical Entomologist” is now on the verge of extinction. Medical entomology is that branch of science which deals with insects and arthropods that impacts human health. It deals with biology, ecology and application of modern tools in the management of vectors and vector‐borne diseases and involves a tremendous outreach to the public, including local and state officials and other stake holders in the interest of public safety.
Training in Medical Entomology in India can be obtained as a part of Medical Curriculum either as an orientation during under graduate student as MBBS or as a during diploma or degree in Public health or community Medicine. It can also be pursued as long term training in Medical Entomology as Master of Science or by short term training offered on in Medical Entomology by few universities in India. Majority of these universities do not have a specialized entomology department but these are associated with department of Zoology and they offer add on short term courses in entomology.
Further analysis of available courses with focused specialization in Entomology in India reveals that in India it is offered either at Doctoral or at Post Graduate level. There is a growing need for trained entomologists in the field of public health in view of emerging and re‐emerging vector‐borne diseases in India. It is also observed that the annual output of trained specialists in medical entomology lags far behind the required need of medical entomologists in the country. Under the National Vector Born Disease Control Program, every district should one trained Entomologist resulting in need of at least one entomologist for 643 districts spread across various geographical distribution in India. Apart from being involved in National Vector Born Disease Control Programme (NVBDCP), Medical Council of India recommendation at least one trained medical entomologists for training and education of medical entomology during undergraduate teaching in Medical College, but majority of the post of Medical Entomology in various medical colleges is lying vacant or is filled by those who are not specialized in Medical Entomology. With paucity of the trained Medical Entomologists in India there is a need to map the Universities offering the courses in Medical Entomology and create a network of medical entomologists and public health experts working on Vector born disease control program in India.
Such network can support arthropod vector surveillance at state and national level. It can also assist in generating the geographical distribution maps of the major arthropod disease vectors and related surveillance activities and assist in defining the priority strategic topics concerning the public health perspective of vector-borne diseases and vector surveillance.
Almost all parties have showcased their manifesto’s now, and health remains a lip service in their agenda’s, basically trying to woo the “aam-janta” on some basic needs that was relevant decades ago. The political class now needs to look at specifics in order to tackle the burgeoning disease burden that India now has, and needs to commit to do more. On this World Health Day, let us commit towards the urgency of developing specialty medicine experts, especially of medical entomology and develop networks of the most important fighter for vector born disease in India or else this species of trained Medical Entomologist might get extinct from India.
(Dr Deepak B. Saxena, is Adjunct Professor at the Indian Institute of Public Health, Gandhi Nagar, Gujarat. Views expressed are personal)