Inside Uttar Pradesh’s Zika outbreak: Can India’s most populous state contain the virus spread?

Laxmi Narayan Mishra had a cold and a mildly scratchy throat for about 10 days when a team from Kanpur’s health department visited his home in the Shyam Nagar locality on October 28 and asked his wife if there was anybody ill in the house.

Mishra blood samples were collected the same day. The next day, the health department told him he had tested positive for Zika.

Zika is a viral infection that primarily spreads through the bite of an infected mosquito, but can also be sexually transmitted. While the infection itself is not fatal, it can trigger a neurological disorder called Guillain-Barré syndrome, which can cause paralysis. In pregnant women, there is an added risk of microcephaly, a birth defect where babies are born with abnormally small heads.

While a few states in India have seen previous Zika outbreaks, Uttar Pradesh had not reported any cases of the infection until October 23, when the first case was detected in Kanpur.

Twenty days later, the number of Zika cases in Kanpur has climbed to 123. Infected cases were initially restricted to a radius of 1-2 km, in colonies like Pokharpur, Adarsh Nagar, Tiwaripur and Harjinder Nagar. But they are now being detected in areas beyond 4 km of the city.

The city has more than 18,000 people living per sq km, over 700 times the population density in Brazil, where Zika became an epidemic in 2015.

More worryingly, Zika cases have also been detected in Lucknow, 94 km from Kanpur, and Kannauj, 84 km away, taking the total number of cases in the state to 127. Six pregnant women are among those infected.

In Kanpur, the epicentre of the outbreak, officials say a massive effort underway to contain the spread: 102 accredited social health activists, 100 field workers, 100 domestic breeding checkers, 15 rapid response teams are at work. Till November 11, 4,142 people had been randomly tested. Over 2.6% had tested positive.

But the overdrive comes after months of inaction – residents of Kanpur alleged no mosquito-control measures had been carried out in the city, until the Zika virus struck.

Measures to detect and destroy the source of mosquitoes and to clear accumulated water must be undertaken immediately after the monsoon season begins, said an official from the National Vector Borne Disease Control Programme, who recently visited the city. “But in Uttar Pradesh, that was delayed,” said the official, who requested anonymity. “It only started when dengue cases started rising in Firozabad, and now with Zika in Kanpur.”

Now, as cases of Zika rise, Shyam Nagar, the locality where Narayan lives, offers a glimpse of the challenge that India’s most populous state faces in containing its spread.

Shyam Nagar is a dense, working-class neighbourhood with houses sharing common walls with one another. The Aedes mosquito that transmits Zika has a flight radius of 100-400 meters and is easily able to cross over from one house to another.

After he tested positive, Narayan received a call from a health official who advised him to stay within a mosquito net for the next 14 days to avoid being bitten by mosquitoes that could spread the infection further. But the 41-year-old event decorator, who had recovered from the cold by then, was keen to return to work. The health advisory, he said, “felt like being jailed.”

While Narayan had symptoms of a viral infection, many infected people are completely asymptomatic. This makes it even harder to persuade them to follow the advice, health officials said.

“The outbreak can be contained only when mosquito breeding is destroyed, there is no other way,” said Dr Himmat Singh, a scientist at the National Institute of Malaria Research.

How the first case was detected

The Zika virus is not new to India. According to the World Health Organisation, it was detected in mosquitoes in the country decades ago.

The first-ever human case, however, was reported from Gujarat in 2016. Since then, cases have been found in Tamil Nadu in 2017, and Rajasthan and Madhya Pradesh in 2018.

This year, Kerala reported the first Zika case in July. Maharashtra recorded a case weeks later. It is unclear how the virus made its way to Uttar Pradesh, more than 1,000 km away. The first case in the state was not detected by the health department – rather, it was an Air Force hospital’s efforts that helped surface it.

A 57-year-old Indian Air Force officer, MM Ali, who is posted in Kanpur, fell ill on October 10. “Initially, we tried treating him at home through paracetamol,” said his daughter Shumbul Ali. In the next couple of days, he became breathless and his eyes reddened. By October 13, his family admitted him to an Air Force hospital. The next day, he was put on ventilator support. His renal, lung and liver functions deteriorated.

“Doctors initially thought it was food poisoning, then suggested it was a snake or spider bite,” Shumbul said. Concerned at the unclear diagnosis, the doctors decided to send his serum and urine sample to the National Institute of Virology in Pune.

On October 22, they got back the report: Ali had tested positive for Zika.

A state-level team of the National Vector Borne Disease Control Programme visited Kanpur on October 23 and submitted a report to their head office the same day warning of an outbreak if mosquito breeding was not controlled. On October 25, a team from New Delhi visited.

State NVBDCP officials suspect the Zika virus started circulating in Kanpur in September or early October. It takes 5-7 days for symptoms to emerge after a mosquito bites, and 80% cases remain asymptomatic. Since multiple cases sprung up within a week of Ali’s diagnosis, officials believe the virus has been circulating since much before.

Nirmal Kumar, an insect collector with the Kanpur health office, said 12 adult mosquitoes and seven breeding sites were found in the Airforce’s hangar number 6, 7 and 8 where Ali works. Subsequently, 16 more personnel of the Air Force were found positive. Some live outside its campus and took the infection to their neighbourhoods.

In Pokharpur, where Ali lives, 15 cases have been found. In Adarsh Nagar, where a 30-year-old Air Force employee lives, nine cases have been found. Maximum cases have been recorded in Harjinder Nagar (27) and in Tiwaripur (15).

The health department sent samples of 116 adult mosquitoes from Kanpur to the National Institute of Malaria Research in Delhi. The Zika virus was found in one pool of three mosquitoes taken from a single house. “This shows that an active local transmission is still happening there,” said Singh, the scientist at the institute.

Delayed mosquito control exercise

While it is unclear how the virus travelled to Kanpur, the factors that helped it spread within the city are easy to map.

In Maharashtra, immediately after the first Zika case surfaced in a woman in Belsar village in rural Pune, Zika testing and entomological surveys to detect mosquito breeding were carried out in the entire village within two days, said state epidemiologist Dr Pradeep Awate.

Within a week, surveys had been done in nearly ten neighbouring villages. “We had found breeding of Aedes Aegypti mosquitoes in water tanks,” said Awate, referring to the mosquito that transmits dengue, zika and chikungunya viruses.

“Villagers were storing water in tanks because supply came once every four days. We ensured daily water supply so that water storage stopped,” Awate added.

Kerala and Maharashtra were able to contain the spread of Zika. While this might partly reflect better governance, Singh, the scientist at the National Institute of Malaria Research, pointed out it was also a function of their population density. He emphasised that the key to containing Zika transmission in an area was clearing mosquito-breeding sites.

But this is a daunting challenge in a state which lacks basic municipal infrastructure.

Renu Rajput, a resident of Kanpur’s Adarsh Nagar locality, said she does not remember the last time an insecticide team came to look for indoor mosquito breeding in her building before Zika cases mushroomed in the city. “Even with so many dengue cases this year no one came for fogging,” she said.

Rajput’s four-year-old daughter is among the 19 children infected with Zika in the state. She knows at least six people in her neighbourhood who have the infection.

Pointing to a swamp behind her house, she blamed it for the rise in mosquitoes. “There are pigs there and the municipal corporation does not clean it. Even after fogging, mosquitoes are everywhere,” she said.

Raghvendra Singh, a malaria inspector, said the swamp was cleaned after Zika cases were reported in the area. “But people are not cooperative. They throw garbage here. When we visit their houses, they refuse entry,” he said.

Suman Shukla, in whose house a Zika case was diagnosed, said the health department and Kanpur municipal corporation have carried intensive fogging and anti-larvae surveys after October 23. “But there are still mosquitoes around. In the last two days nobody came here because Yogi ji (chief minister Adityanath) was visiting Kanpur,” she said.

An Aedes Aegypti mosquito lays eggs in fresh water indoors. It bites mostly during the day time, especially in the morning and the hour before sunset. It needs 6-8 meals – bites that draw blood – before it can lay an egg. Unlike the malaria-spreading Anopheles mosquitoes that bite animals and humans, Aedes only crave for human blood.

It takes 8-10 days for the eggs to mature into a mosquito. “So water containers must be scrubbed within a week to destroy breeding,” said Dinanath Sharma, an insect collector with the Kanpur health department.

Since water supply in some areas of the city is limited to once in a day or two, residents use tankers to store water. Since October 23, of 3.82 lakh water containers surveyed in Kanpur, mosquito breeding was found in 1,225 containers, officials said.

Amit Yadav, a malaria inspector, said the municipal teams have been asked to empty water containers, advise locals against refilling them, and spray a larvicide to kill mosquito-breeding. “But not everyone listens to us,” he said.

Chief medical officer Dr Nepal Singh said fridge trays, unused coolers, and bird feeders are also common mosquito breeding sites. Across 48,660 houses, mosquito breeding was found in 1,066, he said. Yet, he maintained “the situation is under control”.

The numbers are less comforting. Kanpur has been recording new Zika cases on a daily basis. Between October 31 to November 2, Kanpur was testing 400-600 samples a day for Zika, which came down to 200-300 samples a day in the second week of November. Officials said they lack necessary kits for Zika testing in Kanpur and need to send them to Lucknow for RT-PCR testing.

How Kanpur is fighting Zika

While Kanpur municipal authorities may have been lax in carrying out vector-control exercises in the city, after the first Zika cases were found, they have swung into action.

Every morning at 7 am, insect collectors begin house-to-house surveys to trap mosquitoes. By 10 am, a surveillance team starts visiting houses to look for symptomatic people. Another team moves with anti-larvae spray to kill breeding mosquitoes, followed by a fogging machine that works till 2 pm.

In a single day, surveillance teams visit over 10,000 houses to look for people with Zika symptoms, the chief medical officer said. Since October 23, 1.32 lakh houses have been surveyed, according to data maintained by the health department.

Health workers have been asked to paste Zika awareness posters after every ten houses. In the eastern part of the city, where Zika cases are concentrated, every traffic signal has a large hoarding detailing its symptoms – along with images of the chief minister and prime minister.

Officials said that as soon as a Zika case is diagnosed, a rapid response team visits the house, checks if the person needs hospitalisation, counsels the family on wearing full sleeved clothes and advises the person to remain in a mosquito net for 14 days. But state vector control officer Vikas Singhal said he feared many were not following the advice.

In the Lal Bangala area, Kajal Rajput, 20, developed fever towards the end of October. After she tested positive for Zika, she spent a week in Kashiram hospital. When she went back home, health officials asked her to remain in a mosquito net for another week and refrain from stepping out. But her brother, Amit Rajput, said: “She can’t sit in one place the whole day. She moves around, even steps out of the house.”

Outside every infected person’s house, a banner on Zika’s symptoms is hung, a white chart is pasted to tick whether daily fogging and anti-larvae spraying has been carried out. Malaria inspector Vivek Srivastava, in-charge of Tiwaripur, said he has visited every house in the 400-metre radius of an infected case thrice.

Originally posted 15 kms away in a different part of the city, Srivastava has been deputed to oversee the Zika-control exercise in Pokharpur. Like him, several health workers from across the city have been assigned to the seven wards where cases are high.

As a result, surveillance in other parts of the city is poor and no active testing for Zika is being undertaken, even as cases have spread till Lucknow and Kannauj.

“We will start doing Zika surveillance in other wards only if we feel cases are spreading,” said an official from the Kanpur chief medical office. “Right now our focus is the region where there are cases.”

Dr RN Singh, additional chief medical officer, said he was hopeful that Zika cases would decline once the dry winter season sets in. But insect collectors in the city suspect Zika cases will resurface once winter is over. The infected larvae can survive in dry conditions for 6-12 months. Once they get a conducive environment – in this case, water – they could breed again.

All photos by Tabassum Barnagarwala.

This reporting was supported by a grant from the Thakur Family Foundation. Thakur Family Foundation has not exercised any editorial control over the contents of this article.

Corrections and clarifications: An earlier version of the story had incorrectly described microcephaly.