NEW DELHI -- An epidemic of dengue fever in India is fostering a growing sense of alarm, even as government officials have publicly refused to acknowledge the scope of a problem that experts say is threatening hundreds of millions of people -- not just in India, but around the world.
India has become the focal point for a mosquito-borne plague sweeping the globe. Reported in just a handful of countries in the 1950s, dengue is now endemic in half the world's nations.
"The global dengue problem is far worse than most people know, and it keeps getting worse," said Raman Velayudhan, the World Health Organization's lead dengue coordinator.
The tropical disease, though life-threatening for a tiny fraction of those infected, can be extremely painful for many who catch it. Growing numbers of Western tourists are returning from warm-weather vacations with the disease, and it has pierced the shores of the United States and Europe. Last month, health officials in Miami announced a case of locally acquired dengue infection.
In India's capital, hospitals are overrun, and feverish patients are sharing beds and languishing in hallways.
Officials say 30,002 people in India had been sickened with dengue fever through October, a 59 percent jump from the 18,860 recorded for all of 2011. But the real number of Indians who get dengue fever annually is in the millions, several experts said.
"I'd conservatively estimate that there are 37 million dengue infections occurring every year in India, and maybe 227,500 hospitalizations," said Scott Halstead, a tropical disease expert who has focused on dengue research.
A senior Indian government health official, who agreed to speak about the matter only on condition of anonymity, acknowledged that official figures represent a mere sliver of dengue's actual toll. The government only counts cases of dengue that come from public hospitals and that have been confirmed by laboratories, the official said. Such a census, "which was deliberated at the highest levels," is a small subset that is nonetheless informative and comparable from one year to the next, he said.
"There is no denying that the actual number of cases would be much, much higher," the official said. "Our interest has not been to arrive at an exact figure."
The problem with that policy, said Manish Kakkar, a specialist at the Public Health Foundation of India, is that India's "massive underreporting of cases" has contributed to the disease's spread. Experts from around the world said India's failure to construct an adequate dengue surveillance system has impeded awareness of the illness' vast reach, discouraged efforts to clean up the sources of the disease and slowed the search for a vaccine.