Spillover: Animal Infections and the Next Human Pandemic (41 page)

We made the ferry crossing into Faridpur District—dry season, the Padma River was low—and proceeded on a two-lane between the rice paddies. We stopped in Faridpur city to pick up more personnel, a pair of field assistants named Pitu and Gofur, with special skills. Both were small men, as compact and agile as jockeys, expert climbers and bat catchers who had worked intermittently with Epstein for several years. Their bat-catching expertise came from an earlier career in poaching, but now they were on the side of the angels. With them aboard, we turned south, snacking on oranges and spicy cracker mix along the way. We eased through small towns clogged with rickshaws and busses and motorbikes; down here in the southwest, I noticed few private cars. One community seemed to specialize in the quarrying, bagging, and shipping of sand, a resource available in abundance. It was transplanting time for the new rice crop, and we could see men and women bent double, digging the dark green shoots from their thick nursery patches along the river bottoms, bundling them, moving them, replanting them carefully in flooded paddies. On drier ground grew small patches of other crops—corn, beans, grain—and the occasional cluster of banana trees or coconut palms. Drier ground, though, was becoming more scarce as we moved farther south. Straight ahead was the Sundarbans swamp, where the Ganges delta dissolves into mangrove islands and braiding channels and crocodiles and wet-footed tigers, but we weren’t going that far. Already the land was so flat and low, the water table so high, that sumps of stagnant water surrounded every village and town we passed.

Along here we started to see more date palms, their smooth trunks scarred with barber-pole striations showing where gachis had tapped them in years past. It was mid-January now and the sap harvest was on, perfect timing in case we wanted to sample a glassful. We didn’t. Bangladeshis call the stuff
kajul
, I learned from Arif. They believe that it’s a salubrious beverage, killing parasites in the gut. But you’ve got to drink it fresh, Arif said. Boiling the sap ruins not just its taste but also the medicinal effect. He drank it himself as a boy, yeah, sure—but not anymore, no way, not since he’s been working on Nipah.

In midevening we reached a city called Khulna, found rooms in a decent hotel, and the next day went out looking for bat roosts, of which Arif had prescouted several during an earlier trip. West of the city, the land seemed lower still, and water was plentiful—water in paddies, in sumps, in lagoons, in shrimp-raising ponds. Village people and their livestock lived on patches of dirt reached by footpath causeways, and the road itself ran along an embankment, material for which had presumably come from borrow pits that were now the funky greenish and brownish pools alongside. If you wanted high ground here, you had to build it. There were plenty of trees but nothing to call forest, just a scattering of coconut palms, bananas, papayas, tamarinds, a few hardwoods, and many more date palms, into one of which I saw a gachi climbing. He was barefoot, using his hands and feet plus a belt rope to ascend, like a Wichita lineman. He wore a
lungi
(a sarong, knotted at his waist), a turban, and over his shoulder a woven quiver, which held two long, curved knives. Nearby, a small boy on the roadside carried four red clay pots, empty and ready for placement to catch tonight’s drippings.

The bats would be ready too. Meanwhile they were sleeping. Flying foxes, unlike insectivorous bats and some fruit bats, do not roost in caves, mines, or old buildings. They prefer trees, from the branches of which they dangle upside down, wrapped in their wings, like the weirdest of tropical fruit. We visited four or five sites. We gazed up into treetops at aggregations of sleeping bats, talked with locals, and inspected the lay of the land beneath each roost, none of which met Epstein’s exacting standards. Either the bats were too few (a hundred here, a hundred there), the nearby trees or lack of them allowed no way to erect a net, or circumstances were wrong on the ground below. In one village, several hundred bats had established their roost in some legume trees, a tempting cluster, except that they dangled just above a big green puddle that seemed to serve as drain tank and garbage dump for the village. Lowering the net after captures would drop tangled bats into that water, Epstein foresaw, and oblige him to plunge in and untangle them before they drowned. Nope, he muttered. I’d rather take my chances with Nipah than with whatever’s in that bilge.

So we returned to a site we had spotted along the road into Khulna: a derelict storage depot within a walled compound of several acres, government-owned and once used as a repository for road-building materials. From a grassy courtyard there, among the sheds and warehouses, towered a handful of great
karoi
trees in which dangled four or five thousand bats. It was an especially favored roost site, evidently, because the trees were so large, the walled compound protected them from village hubbub and boys with slingshots, and each evening around dusk they could drop from their branches, take flight, circle majestically out over the Rupsha River (another branch of the deltaic Ganges), and flap away for a night’s feeding amid the villages around Khulna. Okay, Epstein decided, this is it.

Within a day, after meetings with local officials, he and Arif had obtained permission for us to go spooking around this old depot in the middle of the night.
That’s
why I like working in Bangladesh, Epstein said. Simple request, reasonable people, prompt action. Go into certain other Asian countries with similar expectations and you’ll see the difference.

Before the bat catching could begin, though, we had to do some daytime groundwork. We climbed a long rickety bamboo ladder to the flat roof of a disused warehouse, just beside the karoi trees, and from that rooftop Gofur and Pitu kept climbing. They went high into one of the trees, nimble as sailors going to the crow’s nest, and lashed a bamboo mast into place so that it towered out vertically above an uppermost limb. Atop that mast was a simple homemade pulley. They did the same in another tree, near the far side of the warehouse, and when their clambering and their rigging were done, they could raise and lower a huge mist net between the two trees.

Their intrusion into a roost tree, of course, disrupted the bats. Hundreds of animals stirred, woke, took flight, and circled out over the river, then back around, and then out again, like flotsam adrift on a great eddy of air. They looked big as geese against the daylight sky, soaring easily on thermals or flapping in slow rhythm. When they came over us, passing low, their features were visible—the auburn fur of their bodies, the big umber wings almost translucent, the pointy snouts. Although they didn’t like being waked, there was no sign of panic. They were magnificent. I had seen fruit bats in Asia before, but never so many in motion so close. I must have been gawking like a fool because Epstein gently advised, “Keep your mouth closed when you look up.” They shed Nipah virus in their urine, he reminded me.

At the hotel, we set our alarms for half past midnight and then roused for the real work. As we rode to the storage depot through slumbering Khulna, Epstein gave us what he called The Safety Briefing. Goggles and leather welder’s gloves for the bat handlers, he said. Medical gloves underneath. Keep your hat on, keep your long sleeves down. When you take hold of such a large bat, you want to grasp it firmly around the back of its head, your fingers and thumb beneath its mandible so it can’t bite you. Avoid being bitten. Avoid being scratched. If a bat hooks a claw into your arm, raise that hand high, over your head; the animal’s instinct is to climb upward, and you don’t want it to climb across your face. Pitu and Gofur will untangle captured bats from the net and then place them into your grasp. Take the head with one hand, get its limbs with the other, clamping each of its strong little ankles and wrists in the gaps between your fingers—one, two, three, four—and your thumb. Four pinch slots, just enough. Trust Pitu and Gofur, they’ll help. That’s how you control a flying fox so that nobody gets hurt. Drop each bat into its pillowcase—which Arif will be holding open—then knot the pillowcase, hang it from a limb, and come back for another bat. If you get scratched or bitten, we treat that as an exposure—possibly to Nipah, possibly also to rabies. We wash the wound for five minutes with soap and then douse it with benzalkonium chloride, a potent antiviral. Immediately after that, jab, you get a rabies booster. Are you vaccinated for rabies, David? (Yes.) When was your last booster, how are your titers? (Um, don’t know.) As for Nipah exposure, never mind, because there’s no vaccine, no treatment, no cure. (What a relief.) Have I said, Don’t get bit? Our first principles are, one, safety for us; two, safety for the bats. Let’s do take good care of the bats, Epstein said. (He’s a veterinarian and a conservationist, before all.) Any questions?

Most of this, thank goodness, was for Jim Desmond’s benefit, not mine. Arif and Pitu and Gofur were seasoned pros; they didn’t need another briefing. Desmond was the real trainee, and I was along to watch. I didn’t intend to let anyone hand me a Nipah-dripping bat if I could reasonably avoid it.

Just outside the compound wall, in another empty building, Epstein had established his field lab. There, in the early wee hours, he and his crew readied their equipment for later tasks: anaesthetizing captured bats, taking blood samples and urine swabs from each animal, centrifuging the blood tubes to allow aliquoting off the serum, and freezing all the samples in a liquid-nitrogen shipper tank. This room had a concrete floor, barred windows, a wooden table now covered with plastic sheeting, and a sterilizing footbath at the door, through which we would come and go in our rubber boots. Epstein issued respirator masks, safety goggles, and medical gloves (not latex, not rubber, but the latest material of choice: nitrile) to everyone, and we suited up. He and Desmond both donned old coveralls. Arif had a nice new Tyvek one-piece suit, like gleaming white footie pajamas. Get something else when you can, Epstein told him gently; these bats are visual, remember, not echolocators, and they can see you. Desmond tried on his respirator, and after a moment Epstein asked, “Can you breathe?”

“Yeah.”

“That’s good. You’re not allowed to pass out. That’s rule number five.” I tried to remember the other four.

Just before pulling his own mask into place, Epstein noted cheerily: “With new and emerging viruses, it’s all about prevention. Once you
have
the virus, there’s not much you can do.” He handed me a small packaged wipe, like the alcohol-laced face fresheners you get on an airplane, except instead of alcohol this thing contained benzalkonium chloride. Ooo, thanks. It was now 2:40 a.m., time to go to the roof.

“All right,” he said. “Are we ready?”

74

T
here was no moon. We marched out through the darkness like Ghostbusters and took turns climbing the long bamboo ladder. The roof of the warehouse was a little spooky in itself, an expanse of tarpaper with a few patches and cracks, old and neglected, not guaranteed to support a person’s weight. Wearing safety glasses that quickly became fogged with vapor leaking up from my respirator, I could scarcely see where I was walking. Worse still, I could scarcely see where the building ended and open space began. About all I could see was Arif, moving around in his Tyvek, pale and diaphanous as Casper the Friendly Ghost. Okay, him we won’t bust. But don’t get distracted, and watch where you step. Rule number six, I realized, is Don’t fall off the roof.

The bats were all out for their nightly feeding. We would lurk here to catch them as they returned, sometime before daylight. Gofur and Pitu had already hoisted the net into place, an invisible wall of delicate mesh in the blackness somewhere above us, big as the screen for a drive-in movie. We hunkered down to wait. The night grew chilly—the first time in my limited Bangladesh experience I’d had occasion to get cold. I lay on my back upon the tarpaper, bundled as best I could be in a light jacket, and went to sleep. The first bat hit the net at 4:22 a.m.

Headlamps came alight, people jumped up, Gofur lowered the net on its pulleys while Epstein and Pitu converged on the animal and I staggered forward after them, safely blinded behind my safety glasses. Pitu untangled the bat and Epstein accepted it, using just the technique he had described: grabbing its head firmly, taking its legs and arms into his finger gaps—binga, binga, binga, binga—and then jouncing the bat into its bag. Close the bag’s neck, tie firmly with a piece of twine. Captured bats, like captured snakes, evidently relax better if you confine them in soft cloth. Reraise the net and repeat. I was impressed by the proficiency of Epstein’s team.

Between the first bat and daylight, before call to prayer even sounded from the local mosques, they bagged five more. Six bats for a night’s work was below par for Epstein—he liked to average about ten—but it was a good start for a new location. Adjustments to the net placement, to the height of the masts, would improve the yield here in coming days. For now, enough. As dawn filtered in, we climbed down the ladder and repaired to the laboratory room. Here again, everybody had an assigned role. Mine was to stay the hell out of the way, and occasionally to assist with a swab.