CLIMATE- THE PRINCIPAL FACTOR INFLUENCING TICK PLETHORA AND TICK-BORNE ZOONOSES: A REVIEW

Global burden of tick-borne diseases to humans and animals is found to be increasing every year. The current scenario in India is also posing a great threat to public health. Each species of ticks prefer different climatic conditions which in turn determine their distribution in different geographic area. Temperature, relative humidity and other weather conditions influence their growth, moulting and reproduction. The history of tick-borne diseases like Kyasanur Forest Disease, Crimean-Congo Hemorrhagic Fever and Indian Tick Typhus is influenced by climate change. Some species of ticks shows exceptional sensitivity to temperature and humidity. The increase in temperature makes nymphal stages shorter and development faster. In case of most tick species, there is an optimum temperature for their successful life and for their capacity of disease transmission. Increased humidity shows an indirect relation to tick mortality. 85% humidity is found to be ideal since they absorb moisture from atmosphere to stay hydrated. Increase in rainfall shows inhibited activity of ticks. Environmental factors along with several anthropogenic factors are responsible for the emergence of tick-borne zoonoses and spreading of diseases from hot spot region to others. Climatic factors are found to have a profound influence on vector biology and disease transmission, it is critical to consider these factors for exploring more effective strategies to reduce the burden of tick-borne disease outbreaks.