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Medical AI Inquiry: You were designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.
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1st symptom of vitamin A deficiency: March 2009
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The correct answer is  Ans. C: Night blindness Vitamin A deficiency is common in developing countries but rarely seen in developed countries. Night blindness is one of the first signs of vitamin A deficiency. Xerophthalmia and complete blindness can also occur since Vitamin A has a major role in phototransduction. Vitamin A deficiency also diminishes the ability to fight infections. In countries where children are not immunized, infectious disease like measles, have higher fatality rates. Even mild, subclinical deficiency can also be a problem, as it may increase children's risk of developing respiratory and diarrheal infections, decrease growth rate, slow bone development and decrease likelihood of survival from serious illness.