Cruz Roja rescue workers were trying to recover the body of a man who fell from a bridge over the Río Virilla Tuesday evening. As they lowered themselves to the river bed, they disturbed a natural hive of honeybees under the bridge. The result was rapid.
Some 15 individuals, most of them standing on the railway right-of-way adjacent to the bridge suffered stings from the bees. Three Cruz Roja workers had to be hospitalized and were reported to be in serious condition.
Among those stung were the children and the wife of the fall victim. Meanwhile, the current seems to have carried away the body while rescue workers were distracted by the bees.
Every hive of honeybees in Costa Rica contains the Africanized strain. The strain started when African bee queens imported by a researcher in Manaus, Brazil, escaped in the late 1950s.
Honeybees are not native to the Americas, and colonists imported the more placid strains from Italy and central Europe, and these spread throughout the two continents over the next several hundred years.
The escaped African bees mated with the European strains in Brazil to produce a hybrid that is known for aggressively guarding its hive. Eventually the genetically superior Africanized bees spread north through Central America. They reached the southern United States in 1990, assisted in part by a similar escape at a Louisiana research lab.
The Africanized bees are physically identical to the European bees, and it takes a DNA test to tell them apart.
Life was not easy for bees in African, so the successful lineages were those that were highly defensive. They also collect honey more efficiently.
The African bees entered the popular culture as Killer Bees, which even spawned a John Belushi characterization on “Saturday Night Live.” There also were a sensational book and at least one horror movie. The African bees do not winter well, which is why they have not moved into the U.S. temperate zones.
In Costa Rica it is not unusual to see hives in hollow trees or even in some of the concrete utility poles, which are hollow.
Firemen get frequent calls to eliminate wild hives of Africanized bees because they are likely to attack humans and animals en masse. Many of the deaths from such bees have been of individuals who could not move quickly to escape, such as someone with a disability or the elderly.
African bees will chase a human victim a half mile or more.
The U.S. Department of Agriculture reports that Africanized bees can build hives in spaces too small for other bees. They swarm frequently. The department recommends not approaching a wild bee hive closer than 100 feet. The insects also are sensitive to vibrations.
The department has this advice for anyone who is attacked:
” . . . Do not stop running until you reach shelter, such as a vehicle or building. A few bees may follow you indoors. However, if you run to a well-lit area, the bees will tend to become confused and fly to windows. Do not jump into water! The bees will wait for you to come up for air. If you are trapped for some reason, cover up with blankets, sleeping bags, clothes, or whatever else is immediately available.”
The department estimates that 500 stings can kill a child but a human can survive 1,100 stings. But some persons with allergies can die from a single sting.
The usual firefighting gear protects the body of rescuers, but the face is left exposed unless a veil is used. Cruz Roja workers Sunday were wearing heavy clothing, which probably spared them from many stings.
African bee venom is not more poisonous than that of other strains, but the bees attack in continual waves. Each bee dies as it stings and loses its stinger. Those removing stingers try to keep from injecting more venom from the attached glands that are left behind.
The fall victim has been identified as Germán José López Alemán. The rail bridge is called locally the Puente Negro. It spans the river between Tibás and Santo Domingo de Heredia. It is a frequent shortcut for residents. López, a Nicaraguan agricultural worker, was crossing the bridge with his son and a work companion when the San José-Heredia train reached the bridge. The other two managed to hang on, but the speculation is that the train hit a backpack being worn by López and knocked him into the river some 30 meters (about 98 feet) below. Rescue workers have been seeking his body since.
Latin American beekeepers have managed to work with Africanized colonies. They try to insulate them from vibrations and pay attention to their daily moods. Beekeepers also are trying to create docile strains in the same way Europeans did long ago with the Italian and bees from the Caucasus.