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Cholera Crisis of 2018Cholera is a disease that is both preventable and treatable, though it can be fatal under the worst of circumstances. It typically affects the most destitute areas of the globe where sanitation practices are weakest. Random outbreaks can and do occur across all continents, however. The greatest challenge to diminishing the effects of a cholera crisis is that it can spread quickly among populations with a lack of adequate hygiene measures, proper vaccination or isolated and contained care centers.

Disease Basics

According to the Center for Disease Control (CDC), cholera is caused by toxigenic Vibrio Cholerae, which leads to the acute bacterial intestinal infection. Symptoms include vomiting, diarrhea and, in severe cases, collapse and shock. Fatalities occur in approximately 25 to 50 percent of all cases. While cholera is uncommon in the U.S. and other developed nations, cases have been increasing around the world since 2005. The CDC classifies the magnitude of cholera outbreaks as a pandemic that has persisted for over four decades in Asia, Africa and Latin America.

Saltwater is the natural source where Vibrio Cholerae originates and may be passed on to humans by ingesting anything from infected water, like shellfish, crab and shrimp. The risk is heightened when any of these foods are undercooked or consumed raw. Cholera can be passed through the drinking water supply as well, which is a common form of transmission.

The Cholera Crisis

A cholera crisis occurred in February 2018 in Uganda, resulting in 700 reported cases and 27 deaths. In Malawi, an outbreak in April affected 893 individuals and caused 30 deaths. A recent outbreak has occurred in Yemen as well. The total number of cholera cases in Yemen over the past year is estimated to be 1,090,280 with 2,275 deaths. This means one out of every five people infected with cholera died last year in Yemen. In addition, Haiti has reported 432 cases of cholera this past year, with four deaths resulting from the disease.

Progressive Efforts

While contemplating the statistics shared in regard to the cholera crisis, it is important to think about what solutions are available to prevent this destructive disease from spreading and to know what actions are being taken to assist those who are suffering. The most obvious solution to a cholera crisis is to offer aid in the form of clean water solutions so potable water can be readily available to all.

The U.N. has made remarkable progress in its efforts to make clean water available to everyone around the world. More specifically, its efforts are known as the Water for Life International Decade for Action and took place during 2005-2015. As a result of this initiative, 1.3 billion people were provided with clean drinking water. It is estimated that there are still 2.5 billion people who drink contaminated water.

Improved sanitation practices and adequate facilities is also a dire need. The U.N. reports that there are currently 2.3 billion people worldwide who are without access to basic sanitation facilities, such as toilets. The two concurrent issues of lack of sanitation facilities and a lack of clean water interplay to cause illness amongst many in the form of communicable diseases passed through to the residents of poverty-stricken areas.  As a result, approximately 1.5 million children die from related illnesses.

Efforts to help can generate a return on investment for those in developed nations. Research has shown that every U.S. dollar spent on improved sanitation generates a return of $9. World Water Day on March 22 and World Toilet Day on Nov. 19 are international observance days set aside to raise awareness of these issues.

– Bridget Rice

Photo: Flickr

Alternatives to Antibiotics for Treatment of Cholera
There has been a recent surge in the number and severity of cholera cases in certain parts of the world, including Haiti, India and South Sudan. In the face of an epidemic, the World Health Organization and its affiliates have mobilized their efforts to distribute efficient treatment and sanitation services to the populations affected by cholera.

The treatment of cholera, like any other bacterial disease, relies on a standard antibiotic therapy accompanied by a steady oral rehydration course for the patients. Cholera — caused by the bacterium Vibrio cholerae — causes severe diarrhea and nausea, and could be potentially fatal as the body gets severely dehydrated. In fact, as many as 142,000 deaths are caused annually as a consequence of cholera.

The disease has long been associated with poverty, with scientific literature to support the correlation as well. The association arises from the causative agent of the disease: the bacteria causing symptoms of cholera thrives in unsanitary water, which is unfortunately widely used as drinking water in impoverished areas. Once they enter the human body, the bacteria have a very short incubation period, and spread quickly and efficiently. The exceptionally virulent bacteria then release toxins, which cause the symptoms of cholera.

To treat these symptoms, antibiotics are typically administered to the patients in tandem with rehydration salts. The antibiotics that function to kill the bacteria are typically of the tetracycline family. The tetracycline-derived antibiotics, however, have become notorious for their rapid decline in clinical efficacy due to antibiotic resistance.

The mode of action of the tetracycline antibiotics is inhibition of protein biosynthesis in the target bacterium. This is accomplished by blocking the bacterial ribosomes, which are the site for protein synthesis. However, many bacteria, including strains of V. cholerae, have developed antibiotic-resistant genes, which efflux the antibiotics from the cell and render them useless.

This resistance to previously one of the most effective, safe and broad-spectrum antibiotics has spurred research into discovering viable alternatives. One of these alternatives is to manufacture a molecule that inhibits toxin production directly. This approach aims to stop the process of bacterial biosynthesis right where it begins: at genetic transcription.

The process of producing cholera toxin also begins with a transcribed gene, which is then translated to a protein toxin. The current objective is to isolate elements within the bacterial DNA that regulate this process, which are called promoters, as well as inhibitors for the promoter. The inhibitory elements can bind to the promoter, which in turn would stop the transcription process for the specific gene altogether.

For the inhibition of the cholera toxin-producing gene, a class of molecules labelled toxT transcription inhibitors have been identified. These not only inhibit the process of toxin production, but also down-regulate the production of colonization factors. The action of toxT therefore can stop the production of disease-causing toxins as well as prevent the bacteria from forming large colonies.

These studies depict a different yet successful possibility of approaching the antibiotic resistance issue. The efficient manufacturing and safety of small molecule inhibitors for mainstream pharmaceuticals remains a challenge for the future; however, the current research results are indicative of a positive outcome.

Atifah Safi

Sources: United Nations, NIH, American Society for Microbiology, WHO
Photo: Mother Earth Living