A United Nations' environment official Monday said the recent outbreak of pneumonic plague in the Democratic Republic of Congo could be linked to environmental conditions. This is one example of what experts note is a growing link between environmental degradation and the rise in infectious diseases.
The head of the environment and health unit at the United Nations Environment Program, Hiremagalur Gopalan, told reporters in Nairobi exposure to mercury and overcrowded living conditions likely played a major role in the recent outbreak of pneumonic plague among miners in the Democratic Republic of Congo.
"They [miners] are also immuno-compromised,” he said. “There is mining activity. They're also exposed to mercury. Mercury is known to reduce the immune activity. And they also live close together. This pneumonic plague is [transmitted] through breathing, through aerosols. So it's possible that it is linked to the environment in which they live."
The World Health Organization (WHO) said last Friday at least 61 miners in Ituri district had died of pneumonic plague. The organization and several health groups are investigating the outbreak, which is believed to have started December 21.
The pneumonic plague outbreak is a recent example of what environmental experts are saying is a rise in new and previously suppressed infectious diseases because of changes people have made to the environment. These include clearing land for agriculture or urban sprawl, or dumping pollutants into the air, water, and land.
This is one of the findings of the U.N.'s Global Environment Outlook Yearbook, released during UNEP's governing council meeting in Nairobi this week.
The deputy director of the United Nations Environment Program's early warning and assessment division, Marion Cheatle, described to reporters how environmental changes have encouraged the breeding of mosquitoes, which, in turn, spread dengue fever and malaria.
"I think all of us are aware of how mosquitoes can be encouraged in areas where we've disturbed the environment, where we've left litter around, where we changed the course of the water system to provide irrigation and big dams, and where there are more breeding places for these insects," she said.
Ms. Cheatle said the incidence of dengue fever and malaria have risen dramatically over time because of urban sprawl and other changes in land-use and human settlement patterns.
She said in the 1970s, there were only about nine countries worldwide that suffered from this disease. Today, dengue has spread to over 100 countries. Similarly in eastern and southern Africa, the proportion of under-five deaths from malaria doubled between the 1980s and 1990s.
Other diseases experts say are linked to the environment include: lyme disease, schistosomiasis, tuberculosis, bubonic plague and cholera.