This map shows how severe India’s swine flu outbreak is this year

One out of every 25 Indians who contracted H1N1 infections this year has died, according to data from the Integrated Disease Surveillance Programme. India is witnessing a surge in swine flu cases this year with 11,752 people testing positive for H1N1 infections. Doctors have said that the burden of the disease might be even higher than the surveillance programme estimates since not all patients with symptoms of H1N1 submit to being tested.

According to infectious diseases expert Dr Om Shrivastav, only an estimated 0.5% to 1.5% of people who contract any seasonal influenza die of the disease. In India, this year 4.5% of people who tested positive for the H1N1 infection have died of it. Symptoms of H1N1 and other influenzas are similar, which makes it challenging for clinicians to diagnose H1N1.

Maharashtra has reported the highest H1N1 toll with 263 fatalities and 1,978 cases of H1N1. A majority of the people who have died in the state are in the age group of between 20 to 45. Unlike in past years, H1N1 seems to be claiming younger victims in 2017, a trend that has puzzled doctors.

“In some deaths, H1N1 was an incidental finding,” said Dr Pradeep Awate, state surveillance officer for Maharashtra, referring to patients who had pre-existing conditions that made them susceptible to H1N1 infections. “If the patient has other co-morbidities which has resulted in death, we cannot blame H1N1.”

State health authorities have now decided to audit all H1N1 deaths to re-confirm what the actual cause of death was. This is not the first time a death audit committee will be instituted to reassess causes of death.

“If a person died while being treated for H1N1, the government cannot say that his death was because of another medical condition, he already had,” said a doctor privy to the discussion of having an audit committee. “This is an attempt to cover up the rising toll.”

Awate added that Maharashtra’s high burden is also a result of better surveillance compared to other parts of the country, implying that there may be similar outbreaks in other parts of the country but not as much reporting.

In Kerala – another state badly affected by swine flu this year – health authorities tested samples of 4,000 people with common colds and found that 27% of them had H1N1 infections. The samples were collected from people complaining of flu-like symptoms from all districts in the state.

A new virus strain

The high H1N1 mortality in Maharashtra is being attributed a new strain of the virus now circulating in India. Till recently, H1N1 infections in India have been caused by the California strain of the H1N1 virus. However, in November last year, scientists at the National Institute of Virology tested samples from infected patients and found the Michigan strain of the virus, that has not been seen in India so far.

A senior official from the institute said that though the Michigan strain is different, its ability to cause mortality is “not higher than the California strain.”

Doctors treating patients with H1N1 have observed a change in symptoms this year. “A patient who looks like a typical case of H1N1, does not test positive when the laboratory investigations are done.” said Shrivastav. “Those who have no telling symptoms, test positive.”

Delay in treatment

The common medicine used to treat H1N1 infections is Oseltamivir and it works best when administered within 48 hours of infection. “The best way to confirm the diagnosis of H1N1 is to start Oseltamivir immediately and, if it is H1N1, the patient starts responding immediately,” said Shrivastav. He emphasised that doctors and patients need not wait for a laboratory to confirm an H1N1 infection to start treatment with Oseltamivir.

In Maharashtra, about 50% of patients who died of H1N1 were administered Oseltamivir only between three to five days after the onset of symptoms.

Officials from the National Centre for Disease Control under the Ministry of Health and Family Welfare visited Maharashtra in June to understand the reason for the high mortality. “It is both, the strain as well as the delay in getting treatment, which has resulted in high mortality,” said Dr AC Dhariwal, director of National Centre for Disease Control.

Dhariwal’s office has directed Maharashtra and other states that have recorded a large number of H1N1 deaths to ensure that patients are treated within 48 hours of being infected.

Meanwhile, the common factor among the majority of H1N1 victims in Kerala are pre-existing conditions that made them susceptible to the H1N1 virus. Of the 58 deaths recorded in Kerala this year, 43 were among those with co-morbidities. “Diabetes was the most common disease among those who died,” said Dr Amar Fettle, Kerala’s nodal officer for H1N1.

Health authorities in both states have urged residents with symptoms of influenza to stay indoors to help control the spread of infection. Mumbai, which has recorded a significant number of cases has urged citizens that, “anyone who has any symptoms suggestive of any influenza like illness should remain at home and avoid crowded places like malls and market.”

Kerala has also asked people to stay indoors.

“We want infected people to take rest,” said Fettle. “The disease is endemic and we don’t think that by curtailing movement, we will be able to reduce the spread.”