After a Belgian was reported as the first victim of an antibiotic-resistant superbug originating in South Asia, three more US citizens have been infected by the virus the New Delhi metallo-lactamase-1 (NDM-1).

It is reported that three Americans from California, Massachusetts and Illinois got infected after receiving medical care in India. American doctors have slammed India that the drug-resistant superbug could easily spread and it is very hard-to-treat infections with people travelling to India.

Doctors said that all three patients had developed urinary tract infections (UTI) that made their cases harder to treat. According to experts, the superbug NDM-1 can be worst for cancer patients and those who have less immunity.

While the Californian woman had gone through hospital care after being involved in a car accident in India, the Illinois man had a UTI problem and the woman from Massachusetts had surgery and chemotherapy for cancer in India before travelling to the US.

However, the superbug is creating a nightmare for India's expanding health tourism industry. More than 150,000 Americans have travelled last year for the cheap medical care in India. Besides, the superbug cases have now been reported in Australia, the UK, Canada, Japan, the Netherlands, and Sweden along with the US.