Is health insurance mandatory in US for any doctor to treat the patients?

Dont the patient get treated if he dont have any health insurance?
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OOPs did not notice that the question is from India. As reported 2/7/10 in The Hindu, India's national newspaper (online) NEW DELHI: The Clinical Establishments (Registration and Regulation Act) Bill, 2010 — approved by the Union Cabinet last month — makes it mandatory for all clinical establishments to provide medical care and treatment to stabilise any person in an emergency condition. If the Bill is passed in Parliament, this will be the first time emergency medical care is made obligatory under law in the country. In 1989, the Supreme Court gave directions that emergency care be not denied to victims under any circumstances. The Law Commission also recommended legislation to make it mandatory. In the United States a federal law the Emergency Medical Treatment and Active Labor Act is a statute which governs when and how a patient may be (1) refused treatment or (2) transferred from one hospital to another when he is in an unstable medical condition. EMTALA was passed as part of the Consolidated Omnibus Budget Reconciliation Act of 1986, and it is sometimes referred to as "the COBRA law". Another very familiar provision, also referred to under the COBRA name, is the statute governing continuation of medical insurance benefits after termination of employment. The essential provisions of the statute are as follows: Any patient who "comes to the emergency department" requesting "examination or treatment for a medical condition" must be provided with "an appropriate medical screening examination" to determine if he is suffering from an "emergency medical condition". If he is, then the hospital is obligated to either provide him with treatment until he is stable or to transfer him to another hospital in conformance with the statute's directives. If the patient does not have an "emergency medical condition", the statute imposes no further obligation on the hospital. A pregnant woman who presents in active labor must, for all practical purposes, be admitted and treated until delivery is completed, unless a transfer under the statute is appropriate. The statute explicitly provides that this must include delivery of the placenta.
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