The number of people dying from malaria¹ in India has been hugely underestimated, according to new research.

一项最新研究显示，印度死于疟疾的人数被远远低估。

The data, published in the Lancet, suggests there are 13 times more malaria deaths in India than the World Health Organization (WHO) estimates.

The authors conclude that more than 200,000 deaths per year are caused by malaria（疟疾，瘴气） .

The WHO said the estimate produced by this study appears too high.

The research was funded by the US National Institutes of Health, the Canadian Institute of Health Research and the Li Ka Shing Knowledge Institute.

The new figures raise doubts over the total number of malaria deaths worldwide.

Difficult diagnosis²

Calculating how many people die from malaria is extremely difficult. Most cases that are diagnosed and treated do not result in fatalities³（死亡，灾祸） .

People who die of extremely high fevers in the community can be misdiagnosed and the cause of death can be attributed to other diseases and vice⁴ versa（反之亦然） .

As most deaths in India occur at home, without medical intervention⁵, cause of death is seldom medically certified⁶.

There are about 1.3 million deaths from infectious diseases, where acute fever is the main symptom in rural areas in India.

In this study, trained field workers interviewed families, asking them to describe how their relative died. Two doctors then reviewed each description and decided⁷ if the death was caused by malaria. This method is called verbal autopsy⁸（验尸） .

Some 122,000 premature⁹ deaths between 2001 and 2003 were investigated.

The data suggests that 205,000 deaths before the age of 70, mainly in rural areas, are caused by malaria each year.

'Serious doubts'

The WHO estimated that malaria caused between 10,000-21,000 deaths in India in 2006.

The UN health agency welcomed new efforts to estimate the number of malaria deaths.

Dr Robert Newman, the director of its global malaria programme, said: "It is vital to evaluate cause of death correctly because different diseases require different strategies for control."

He concedes that WHO current evaluation¹⁰ methods have their limitations, but has serious doubts about the high estimates from this study.

Verbal autopsy, he said, was not a trustworthy（可靠的） method for counting malaria deaths because the symptoms of malaria are shared with many other common causes of acute fever.

This, he said, along with what the WHO called "implausibly（难以置信地） high case incidence rates", indicates that the findings of this study cannot be accepted without further validation¹¹.

He added that the WHO is working closely with the Indian government in the fight against the disease.