For Deepak Jena, a labourer on a remote island in the Sundarbans delta in India, getting a Covid-19 vaccine was proving to be difficult. Then a government boat arrived with vaccines.
Home to more than 4.5 million people and the largest mangrove forest in the world, residents of the Bay of Bengal delta endure all the miseries nature throws at them - from cyclones to erosion.
But the pandemic is testing a region with only basic healthcare facilities.
"It's very difficult to get vaccinated in this village area," said Jena. "We used to line up at crowded hospitals to get a shot", unsuccessfully, before the boat came along.
The state government of West Bengal, where the Indian side of the Sundarbans is located, has launched a "vaccination on boat" programme to reach the remotest parts of the forested area. On the other side is Bangladesh.
"We have targeted some migrant people and the people who can't reach our sub-centre ... or any other session site (for coronavirus vaccinations)," said Indranil Bargi, a medical officer in the Gosaba area.
AstraZeneca and partner Serum Institute of India's Covishield is being used for the vaccination drive.
More than 400,000 people have died from Covid-19 in India and the government is trying to expand its immunisation drive to protect more people.
But logistical challenges of reaching remote islands and treacherous villages in the mountains have complicated the immunisation effort.
