Cholera

Cholera

Cholera
Cholera is an acute diarrhoeal infection caused by ingestion of food or water contaminated with the bacterium Vibrio cholerae. Cholera remains a global threat to public health and an indicator of inequity and lack of social development. Researchers have estimated that every year, there are roughly 1.3 to 4.

0 million cases, and 21 000 to 143 000 deaths worldwide due to cholera (1).

Cholera is an extremely virulent disease that can cause severe acute watery diarrhoea. It takes between 12 hours and 5 days for a person to show symptoms after ingesting contaminated food or water (2).

Cholera affects both children and adults and can kill within hours if untreated.

Most people infected with V. cholerae do not develop any symptoms, although the bacteria are present in their faeces for 1-10 days after infection and are shed back into the environment, potentially infecting other people.

Among people who develop symptoms, the majority have mild or moderate symptoms, while a minority develop acute watery diarrhoea with severe dehydration. This can lead to death if left untreated.

During the 19th century, cholera spread across the world from its original reservoir in the Ganges delta in India. Six subsequent pandemics killed millions of people across all continents. The current (seventh) pandemic started in South Asia in 1961, and reached Africa in 1971 and the Americas in 1991. Cholera is now endemic in many countries.

There are many serogroups of V. cholerae, but only two – O1 and O139 – cause outbreaks. V. cholerae O1 has caused all recent outbreaks. V. cholerae O139 – first identified in Bangladesh in 1992 – caused outbreaks in the past, but recently has only been identified in sporadic cases. It has never been identified outside Asia. There is no difference in the illness caused by the two serogroups.

Cholera can be endemic or epidemic. A cholera-endemic area is an area where confirmed cholera cases were detected during the last 3 years with evidence of local transmission (meaning the cases are not imported from elsewhere). A cholera outbreak/epidemic can occur in both endemic countries and in countries where cholera does not regularly occur.

In cholera endemic countries an outbreak can be seasonal or sporadic and represents a greater than expected number of cases. In a country where cholera does not regularly occur, an outbreak is defined by the occurrence of at least 1 confirmed case of cholera with evidence of local transmission in an area where there is not usually cholera.

Cholera transmission is closely linked to inadequate access to clean water and sanitation facilities. Typical at-risk areas include peri-urban slums, and camps for internally displaced persons or refugees, where minimum requirements of clean water and sanitation are not been met.

The consequences of a humanitarian crisis – such as disruption of water and sanitation systems, or the displacement of populations to inadequate and overcrowded camps – can increase the risk of cholera transmission, should the bacteria be present or introduced. Uninfected dead bodies have never been reported as the source of epidemics.

The number of cholera cases reported to WHO has continued to be high over the last few years. During 2017,1 227 391 cases were notified from 34 countries, including 5654 deaths (3). The discrepancy between these figures and the estimated burden of the disease is since many cases are not recorded due to limitations in surveillance systems and fear of impact on trade and tourism. 

A multifaceted approach is key to control cholera, and to reduce deaths. A combination of surveillance, water, sanitation and hygiene, social mobilisation, treatment, and oral cholera vaccines are used.

Cholera surveillance should be part of an integrated disease surveillance system that includes feedback at the local level and information-sharing at the global level.

Cholera cases are detected clinical suspicion in patients who present with severe acute watery diarrhoea. The suspicion is then confirmed by identifying V. cholerae in stool samples from affected patients.

Detection can be facilitated using rapid diagnostic tests (RDTs), where one or more positive samples triggers a cholera alert.  The samples are sent to a laboratory for confirmation by culture or PCR.

Local capacity to detect (diagnose) and monitor (collect, compile, and analyse data) cholera occurrence, is central to an effective surveillance system and to planning control measures.

Countries affected by cholera are encouraged to strengthen disease surveillance and national preparedness to rapidly detect and respond to outbreaks.

Under the International Health Regulations, notification of all cases of cholera is no longer mandatory.

However, public health events involving cholera must always be assessed against the criteria provided in the regulations to determine whether there is a need for official notification.

The long-term solution for cholera control lies in economic development and universal access to safe drinking water and adequate sanitation.

Actions targeting environmental conditions include the iimplementation of adapted long-term sustainable WASH solutions to ensure use of safe water, basic sanitation and good hygiene practices in cholera hotspots.

  In addition to cholera, such interventions prevent a wide range of other water-borne illnesses, as well as contributing to achieving goals related to poverty, malnutrition, and education.  The WASH solutions for cholera are aligned with those of the Sustainable Development Goals (SDG 6).

Cholera is an easily treatable disease. The majority of people can be treated successfully through prompt administration of oral rehydration solution (ORS). The WHO/UNICEF ORS standard sachet is dissolved in 1 litre (L) of clean water. Adult patients may require up to 6 L of ORS to treat moderate dehydration on the first day.

Severely dehydrated patients are at risk of shock and require the rapid administration of intravenous fluids. These patients are also given appropriate antibiotics to diminish the duration of diarrhoea, reduce the volume of rehydration fluids needed, and shorten the amount and duration of V. cholerae excretion in their stool.

Mass administration of antibiotics is not recommended, as it has no proven effect on the spread of cholera may contribute to antimicrobial resistance.

Rapid access to treatment is essential during a cholera outbreak. Oral rehydration should be available in communities, in addition to larger treatment centres that can provide intravenous fluids and 24 hour care. With early and proper treatment, the case fatality rate should remain below 1%.

Zinc is an important adjunctive therapy for children under 5, which also reduces the duration of diarrhoea and may prevent future episodes of other causes of acute watery diarrhoea.

Breastfeeding should also be promoted.

Health education campaigns, adapted to local culture and beliefs, should promote the adoption of appropriate hygiene practices such as hand-washing with soap, safe preparation and storage of food and safe disposal of the faeces of children. Funeral practices for individuals who die from cholera must be adapted to prevent infection among attendees.

Further, awareness campaigns should be organised during outbreaks, and information should be provided to the community about the potential risks and symptoms of cholera, precautions to take to avoid cholera, when and where to report cases and to seek immediate treatment when symptoms appear. The location of appropriate treatment sites should also be shared.

Community engagement is key to long term changes in behaviour and to the control of cholera.

Currently there are three WHO pre-qualified oral cholera vaccines (OCV): Dukoral®, Shanchol™, and Euvichol-Plus®. All three vaccines require two doses for full protection.

Dukoral® is administered with a buffer solution that, for adults, requires 150 ml of clean water. Dukoral can be given to all individuals over the age of 2 years.

There must be a minimum of 7 days, and no more than 6 weeks, delay between each dose. Children aged 2 -5 require a third dose. Dukoral® is mainly used for travellers.

Two doses of Dukoral® provide protection against cholera for 2 years.

Shanchol™ and Euvichol-Plus® are essentially the same vaccine produced by two different manufacturers. They do not require a buffer solution for administration. They are given to all individuals over the age of one year.

There must be a minimum of two weeks delay between each dose of these two vaccines. Two doses of Shanchol™ and Euvichol-Plus® provide protection against cholera for three years, while one dose provides short term protection.

Shanchol™ and Euvichol-Plus® are the vaccines currently available for mass vaccination campaigns through the Global OCV Stockpile. The stockpile is supported by Gavi, the Vaccine Alliance.

the available evidence, the August 2017 WHO Position Paper on Vaccines against Cholera states that:

  • OCV should be used in areas with endemic cholera, in humanitarian crises with high risk of cholera, and during cholera outbreaks; always in conjunction with other cholera prevention and control strategies;
  • vaccination should not disrupt the provision of other high priority health interventions to control or prevent cholera outbreaks.

More than 30 million doses of OCV have been used in mass vaccination campaigns. The campaigns have been implemented in areas experiencing an outbreak, in areas at heightened vulnerability during humanitarian crises, and among populations living in highly endemic areas, known as “hotspots”.

  • More information on cholera vaccines
  • The 2017 WHO OCV position paper

In 2014 the Global Task Force on Cholera Control (GTFCC), with its Secretariat based at WHO, was revitalised. The GTFCC is a network of more than 50 partners active in cholera control globally, including academic institutions, non-governmental organisations and United Nations agencies.

Through the GTFCC and with support from donors, WHO works to:

  • promote the design and implementation of global strategies to contribute to capacity development for cholera prevention and control globally;
  • provide a forum for technical exchange, coordination, and cooperation on cholera-related activities to strengthen country capacity to prevent and control cholera;
  • support countries for the implementation of effective cholera control strategies and monitoring of progress;
  • disseminate technical guidelines and operational manuals;
  • support the development of a research agenda with emphasis on evaluating innovative approaches to cholera prevention and control in affected countries; and
  • increase the visibility of cholera as an important global public health problem through the dissemination of information about cholera prevention and control, and conducting advocacy and resource mobilization activities to support cholera prevention and control at national, regional, and global levels.
  • More about the Global Task Force on Cholera Control (GTFCC)

In October 2017, GTFCC partners launched a strategy for cholera control Ending Cholera: A global roadmap to 2030. The country led strategy aims to reduce cholera deaths by 90% and to eliminate cholera in as many as 20 countries by 2030.

The Global Roadmap focuses on three strategic axes:

  1. Early detection and quick response to contain outbreaks: the strategy focuses on containing outbreaks—wherever they may occur— through early detection and rapid multisectoral response including community engagement, strengthening surveillance and laboratory capacity, health systems and supply readiness, and establishing rapid response teams.
  2. A targeted multi-sectoral approach to prevent cholera recurrence: the strategy calls on countries and partners to focus on cholera “hotspots”, the relatively small areas most heavily affected by cholera. Cholera transmission can be stopped in these areas through measures including improved WASH and through use of OCV.
  3. An effective mechanism of coordination for technical support, advocacy, resource mobilisation, and partnership at local and global levels: The GTFCC provides a strong framework to support countries to intensify efforts to control cholera, building upon country-led cross-sectoral cholera control programs and supporting them with human, technical, and financial resources.

A resolution promoting control of cholera and endorsing “Ending Cholera: A global roadmap to 2030” was passed in May 2018 at the 71st World Health Assembly,

More about the strategy

To ensure efficient and effective deployment of necessary materials for the investigation and confirmation of cholera outbreaks, as well as the treatment of cholera patients, WHO has developed a set of cholera kits.

After consultation with implementing partners, WHO revised the cholera kits in 2016 to better meet field needs. In total there are 6 kits:

  • 1 for investigation
  • 1 with supplies for laboratory confirmation
  • 3 for treatment at the community, peripheral and central levels
  • 1 support kit with logistical materials such as solar lamps, fencing and water bladders and taps.

Each treatment kit provides enough material to treat 100 patients. The revised cholera kits are designed to help prepare for a potential cholera outbreak and to support the first month of the initial response.

References

(1) Updated global burden of cholera in endemic countries.

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4455997/

Ali M, Nelson AR, Lopez AL, Sack D. (2015). PLoS Negl Trop Dis 9(6): e0003832. doi:10.1371/journal.pntd.0003832.

(2) The incubation period of cholera: a systematic review.https://www.ncbi.nlm.nih.gov/pubmed/23201968

Azman AS, Rudolph KE, Cummings DA, Lessler J. J Infect. 2013;66(5):432-8. doi: 10.1016/j.jinf.2012.11.013. PubMed PMID: 23201968; PubMed Central PMCID: PMC3677557.

Source: https://www.who.int/news-room/fact-sheets/detail/cholera

What Are the Signs and Symptoms of Cholera?

When someone is infected with the cholera bacteria, symptoms can appear in a few hours or as late as 5 days later. Some people with cholera have no signs or symptoms, but some cases are severe and can be life-threatening.

Common symptoms of cholera and the dehydration it causes include:

  • watery, pale-colored diarrhea, often in large amounts
  • nausea and vomiting
  • cramps, particularly in the abdomen and legs
  • irritability, lack of energy, or unusual sleepiness
  • glassy or sunken eyes
  • dry mouth and extreme thirst
  • dry, shriveled skin
  • low urine (pee) output and a lack of tears
  • irregular heartbeat (arrhythmia) and low blood pressure

Cholera can cause watery diarrhea and vomiting, making people who have it get dehydrated quickly. When is severe, it can cause serious health problems if it's not treated. It can even cause seizures and kidney failure. People who don't get the proper medical treatment may even die.

What Causes Cholera?

People get it from drinking water or eating food that's contaminated with a type of bacteria called Vibrio cholerae.

Cholera is mostly found in the tropics — in particular Asia, Africa, Latin America, India, and the Middle East. It's rare in the United States, but people can still get it. People who travel from countries where the infection is more common can bring cholera into the U.S. Some people in the U.S. have become sick from eating raw and undercooked shellfish from the Gulf of Mexico.

How Do People Get It?

People get cholera from eating or drinking food or water that's been contaminated with the feces (poop) of someone who has cholera. This is one reason why cholera is rare in countries with good sanitation systems. Things flush toilets, sewer systems, and water treatment facilities keep poop the water and food supply.

But for people living in places without good sanitation, cholera is more of a risk. Cholera epidemics can also sometimes happen after a disaster ( an earthquake or flood) if people are living in tent cities or other places without running water or proper sanitation systems.

Cholera is not contagious, so you can't catch it from direct contact with another person.

When Should I Call a Doctor?

If you develop symptoms of cholera, especially after visiting an area where the disease is common, call your doctor or get medical help right away. Severe dehydration can happen very quickly, so it's essential to start replacing lost fluids right away.

If you have a severe case of diarrhea or vomiting, call a doctor immediately, even if you're pretty sure it's not cholera. Dehydration is a serious medical condition regardless of the cause, and it needs to be treated quickly before it can do damage to internal organs.

How Is Cholera Diagnosed?

To confirm a diagnosis of cholera, doctors may take a or vomit sample to examine for signs of the bacteria.

How Is Cholera Treated?

Cholera needs immediate treatment because severe dehydration can happen within hours. Fortunately, treatment is simple and very effective. Very few people who get treatment die.

The goal of cholera treatment is to replace all the fluids and electrolytes (salts) lost through diarrhea and vomiting. For mild dehydration, a doctor may recommend drinking an over-the-counter rehydration solution. People with more severe cases of cholera may need to stay in the hospital and get (IV) fluids.

Sometimes doctors prescribe to treat cholera. The antibiotics are not as important as rehydrating, but they can help shorten the length of time a person is sick. They also might make cholera-related diarrhea less severe. Sometimes doctors also prescribe zinc supplements.

Anti-diarrheal medicines can actually make the symptoms of cholera worse, so people who think they may have cholera should avoid taking them.

Can Cholera Be Prevented?

In some areas cholera vaccines are given to help protect people against cholera for a short while. Because cholera isn't a problem in the United States, the vaccine is not offered here.

If you're going to an area that has cholera, you can greatly reduce your risk of getting the disease by following a few simple precautions when you get there:

  • Boil or disinfect any water that you'll use for drinking, washing or preparing food, making ice, making coffee or tea, or brushing your teeth. Choose bottled water or other drinks that come in sealed cans or bottles. Be sure to wipe the outside of the can or bottle before you drink from it, though. Avoid tap water, fountain drinks, and drinks with ice cubes.
  • Fully cook all food, especially seafood. Avoid food from street vendors. Instead, eat packaged foods and meals that are freshly cooked and served hot. Avoid sushi and any other raw or partly cooked seafood.
  • Avoid raw vegetables, including salads, and fruits that have already been peeled or cannot be peeled grapes and berries. Bananas, avocados and oranges make better choices.
  • Dairy foods are often contaminated, so be careful with things ice cream, milk, and cheese. Eat only pasteurized dairy and be sure dairy foods are refrigerated and kept cold.
  • Wash your hands well and often with soap and clean water, especially after you use the bathroom or before you prepare food. If no soap and water are available, use a hand cleaner that's at least 60% alcohol.

If you're planning to visit the tropics, especially an area that doesn't have good sanitation, it's a good idea to know the signs of cholera and what to do. Taking precautions with your food and water is the best way to avoid the disease.

Reviewed by: Steven Dowshen, MD

Date reviewed: November 2017

Source: https://kidshealth.org/en/teens/cholera.html

General Information

Cholera

Below you will find answers to commonly asked questions about cholera.

Frequently Asked Questions

Cholera is an acute, diarrheal illness caused by infection of the intestine with the toxigenic bacterium Vibrio cholerae serogroup O1 or O139. An estimated 2.9 million cases and 95,000 deaths occur each year around the world.

The infection is often mild or without symptoms, but can sometimes be severe. Approximately one in 10 (10%) infected persons will have severe disease characterized by profuse watery diarrhea, vomiting, and leg cramps.

In these people, rapid loss of body fluids leads to dehydration and shock. Without treatment, death can occur within hours.

The cholera bacterium is usually found in water or food sources that have been contaminated by feces (poop) from a person infected with cholera. Cholera is most ly to be found and spread in places with inadequate water treatment, poor sanitation, and inadequate hygiene.

The cholera bacterium may also live in the environment in brackish rivers and coastal waters. Shellfish eaten raw have been a source of cholera, and a few persons in the U.S. have contracted cholera after eating raw or undercooked shellfish from the Gulf of Mexico.

A person can get cholera by drinking water or eating food contaminated with the cholera bacterium. In an epidemic, the source of the contamination is usually the feces of an infected person that contaminates water and/or food.

The disease can spread rapidly in areas with inadequate treatment of sewage and drinking water.

The disease is not ly to spread directly from one person to another; therefore, casual contact with an infected person is not a risk for becoming ill.

Cholera infection is often mild or without symptoms, but can sometimes be severe. Approximately one in ten (10%) infected persons will have severe disease characterized by profuse watery diarrhea, vomiting, and leg cramps. In these people, rapid loss of body fluids leads to dehydration and shock. Without treatment, death can occur within hours.

It can take anywhere from a few hours to 5 days for symptoms to appear after infection. Symptoms typically appear in 2-3 days.

Individuals living in places with unsafe drinking water, poor sanitation, and inadequate hygiene are at a greater risk for cholera.

If you think you or a member of your family may have cholera, seek medical attention immediately. Dehydration can be rapid so fluid replacement is essential.

If you have oral rehydration solution (ORS), the ill person should start taking it immediately; it can save a life. He or she should continue to drink ORS at home and during travel to get medical treatment.

If you have an infant who has watery diarrhea, continue to breastfeed.

To test for cholera, doctors must take a stool sample or a rectal swab and send it to a laboratory to look for the cholera bacterium.

Cholera can be simply and successfully treated by immediate replacement of the fluid and salts lost through diarrhea.

Patients can be treated with oral rehydration solution (ORS), a prepackaged mixture of sugar and salts to be mixed with 1 liter of water and drunk in large amounts. This solution is used throughout the world to treat diarrhea.

Severe cases also require intravenous fluid replacement. With prompt appropriate rehydration, fewer than 1% of cholera patients die.

Antibiotics shorten the course and diminish the severity of the illness, but they are not as important as receiving rehydration. Persons who develop severe diarrhea and vomiting in countries where cholera occurs should seek medical attention promptly.

The disease is not ly to spread directly from one person to another; therefore, casual contact with an infected person is not a risk for becoming ill.

The risk for cholera is very low for people visiting areas with epidemic cholera. When simple precautions are observed, contracting the disease is unly.

All people (visitors or residents) in areas where cholera is occurring or has occurred should observe the following recommendations:

The FDA recently approvedExternal a single-dose live oral cholera vaccine called Vaxchora® (lyophilized CVD 103-HgR) for adults 18 – 64 years old who are traveling to an area of active cholera transmission with toxigenic Vibrio cholerae O1 (the bacteria strain that most commonly causes cholera). The vaccine is not routinely recommended for most travelers from the United States, as most people do not visit areas of active cholera transmission. Three other oral inactivated, or non-live cholera vaccines, Dukoral®, ShanChol®, and Euvichol-Plus®/Euvichol® are World Health Organization (WHO) prequalified, but these vaccines are not available in the U.S. No cholera vaccine is 100% protective and vaccination against cholera is not a substitute for standard prevention and control measures, including precautions for food and water as outlined above.

For more information, please visit the Vaccines page.

In the U.S., cholera was prevalent in the 1800s but water-related spread has been eliminated by modern water and sewage treatment systems.  Very rarely, persons in the US acquire cholera from shellfish consumed raw or inadequately cooked.

However, U.S. travelers to areas with epidemic cholera (for example, parts of Africa, Asia, or Latin America) may be exposed to the cholera bacterium. In addition, travelers may bring contaminated seafood back to the U.S.; foodborne outbreaks of cholera have been caused by contaminated seafood brought into the U.S. by travelers.

The global picture of cholera changes periodically, so travelers should seek updated information on countries of interest. CDC has a Travelers’ Health Website that contains information on cholera and other diseases of concern to travelers.

U.S. and international public health authorities are working to enhance surveillance for cholera, investigate cholera outbreaks, and design and implement preventive measures across the globe.

The Centers for Disease Control and Prevention (CDC) investigates epidemic cholera wherever it occurs at the invitation of the affected country and trains laboratory workers in proper techniques for identification of Vibrio cholerae.

In addition, CDC provides information on diagnosis, treatment, and prevention of cholera to public health officials and educates the public about effective preventive measures.

The U.S. Agency for International Development sponsors some of the international U.S. government activities and provides medical supplies, and water, sanitation and hygiene supplies to affected countries.

The Food and Drug Administration tests imported and domestic shellfish for V. cholerae and monitors the safety of U.S. shellfish beds through the shellfish sanitation program.

With cooperation at the state and local, national, and international levels, assistance will be provided to countries where cholera is present. The risk to U.S. residents remains small.

Source: https://www.cdc.gov/cholera/general/index.html

Cholera Fact Sheet

Cholera

Cholera is a bacterial disease that causes diarrhea (loose stool/poop) and is caused by the bacteria calledVibrio cholerae. Although only a few cases are recognized in the United States each year, many cases are identified each year in portions of Africa, South and Central America, and Southeast Asia.

Who gets cholera?

While cholera is a rare disease in the U.S.

, people who may be at risk are those traveling to foreign countries where outbreaks are occurring and those who consume raw or undercooked seafood from warm coastal waters that may be exposed to sewage contamination.

In both instances, the risk is small. Individuals living in places with inadequate water treatment, poor sanitation, and inadequate hygiene (cleanliness) are at a greater risk for cholera.

How is cholera spread?

The cholera bacteria is passed through feces (poop). It is spread by eating or drinking food or water contaminated by the feces (poop) of an infected person. This occurs more often in underdeveloped countries lacking proper water supplies and sewage disposal. It is not ly that cholera is spread directly from one person to another.

What are the symptoms of cholera and when do they appear?

People infected with cholera may experience mild to severe watery diarrhea (loose stool/poop), vomiting, and dehydration (loss of water in the body causing weakness or dizziness). The symptoms may appear from a few hours to five days after eating or drinking contaminated food or water.

How is cholera diagnosed?

Cholera is diagnosed when the cholera bacteria, Vibrio cholerae, is found in a stool sample or rectal swab.

What is the treatment for cholera?

Cholera can be treated simply and successfully by immediate replacement of the fluid and salts lost through diarrhea (loose stool/poop).

Patients can be treated with an oral rehydration solution, a prepackaged mixture of sugar and salts mixed with water in large amounts. This solution is used throughout the world to treat diarrhea.

Severe cases also require intravenous fluid replacement. With prompt rehydration, less than 1% of cholera patients die.

Antibiotics shorten the course and diminish the severity of the illness, but they are not as important as receiving rehydration. Persons who develop severe diarrhea and vomiting in countries where cholera occurs should seek medical attention promptly.

Does past infection with cholera make a person immune?

People can be reinfected with cholera if they are exposed to the bacteria again.

Is there a vaccine for cholera?

The FDA recently approved a single-dose live oral cholera vaccine called Vaxchora (lyophilized CVD 103-HgR) for adults 18 – 64 years old who are traveling to an area of active cholera transmission with toxigenic Vibrio cholerae O1 (the bacteria strain that most commonly causes cholera).

The vaccine is not routinely recommended for most travelers from the United States, as most people do not visit areas of active cholera transmission. Two other oral inactivated (or non-live cholera vaccines), Dukoral® and ShanChol®, exist but these vaccines are not available in the U.S.

No cholera vaccine is 100% protective and vaccination against cholera is not a substitute for standard prevention and control measures.

How can the spread of cholera be prevented?

The single most important preventive measure is to avoid consuming uncooked foods or water in foreign countries where cholera occurs unless they are known to be safe or have been properly treated (for example, sealed bottled, boiled, or chemically treated water). In addition, it is important to wash your hands often with soap and clean water or an alcohol based hand cleanser, particularly before you eat or prepare foods and after using the bathroom.

Source: https://www.health.ny.gov/diseases/communicable/cholera/fact_sheet.htm

Transmission

Cholera is transmitted by ingesting food or water contaminated with V. cholerae. The contamination occurs when fecal matter from a sick person comes into contact with food or water supplies.

In areas with poor environmental management and overcrowding, the risk of cholera increases dramatically.

Ensuring that food and water supplies are clean and well managed is the easiest way to prevent the spread of cholera.

The development and use of piped water systems, chlorination facilities, water filtration, safe water storage containers, and proper sewage disposal have helped reduce the spread of cholera.

Cholera is typically not spread directly from one person to another.

Treatment and Care

People who are ill with cholera can be treated with oral rehydration fluids. Intravenous fluids may be administered if the patient is severely dehydrated.

Antibiotics may be used to reduce the severity of symptoms. However, widespread use of antibiotics in areas with many cases of cholera is generally not recommended. Antibiotics do not prevent spread of the disease, and they may lead to V. cholerae’s increasing antimicrobial resistance.

Complications

In extreme cases of cholera, diarrhea can be so profuse that severe dehydration sets in, which can lead to sunken eyes, cold skin, decreased skin elasticity, wrinkling of the hands and feet, and a bluish tint to the skin.

Death can occur within hours of symptom onset if the patient does not receive treatment.

Available Vaccines and Vaccination Campaigns

Several oral cholera vaccines are available globally.

The vaccines provide about 65%-85% protection from clinically significant cholera for a period of time from 4 months after vaccination to up to 5 years after vaccination, depending on the vaccine.

Because vaccine effectiveness is somewhat low and short-term, cholera vaccines are used mainly for outbreak control and emergency use, rather than for routine vaccination.

U.S. Vaccination Recommendations

Cholera vaccination is not routinely recommended in the United States. Water-related spread of cholera bacterium has been eliminated in the United States due to modern water and sewage treatment systems.

U.S. residents who travel to an area with epidemic cholera (that is, parts of Africa, Asia, or Latin America) should consult a travel physician about cholera vaccination.

An oral cholera vaccine (Cholera Vaccine, Live, Oral, [Vaxchora® ]) is approved for adults age 18-64 traveling to cholera-afflicted areas.

Travelers to such areas are also advised to practice simple safeguards, such as drinking only bottled water and washing hands frequently.

Sources

Source: https://www.historyofvaccines.org/content/articles/cholera

Cholera: Background, Pathophysiology, Etiology

Cholera

In the United States, cholera has virtually been eliminated because of improved hygiene and sanitation systems.

Individuals living in the United States most often acquire cholera through travel to cholera-endemic areas or through consumption of undercooked seafood from the Gulf Coast or foreign waters.

Between January 1, 1995, and December 31, 2000, 61 cases of cholera were reported in 18 states and 2 US territories. Thirty-seven were travel-associated cases; the other 24 cases were acquired in the United States. [5]

A unique strain of V cholerae O1 (biotype El Tor, serotype Inaba), which is related closely to, but distinguishable from, the strain of the seventh pandemic was recognized in Louisiana and along the Gulf of Mexico in 1973.

Since then, this strain has become indigenous to the Gulf coast, although its environmental reservoirs and ecology remain unclear.

Of note, none of the toxigenic V cholerae strains associated with the US Gulf Coast (01, 0141, and 075) have caused more than sporadic cases and small outbreaks of diarrhea in the United States. [6]

In October 2005, toxigenic V cholerae infection due to the consumption of contaminated and improperly cooked seafood was reported from Louisiana after Hurricanes Katrina and Rita. [7]

The incidence of Vibrio infection in the United States continues to be low, with highest number documented in the age group older than 50 years, which has been around 0.50 cases per 100,000 population from 2003-2008.

The frequency of cholera among international travelers returning to the United States has averaged 1 case per 500,000 population, with a range of 0.05-3.7 cases per 100,000 population, depending on the countries visited.

The number of patients with cholera worldwide is uncertain because most cases go unreported. ly contributory factors are as follows:

  • Most cases occur in remote areas of developing countries where definitive diagnosis is not possible

  • Reporting systems often are nonexistent in such areas

  • The stigma of cholera, which has direct adverse effects on commercial trade and tourism, discourages reporting

  • Many countries with endemic cholera do not report at all

In 1990, fewer than 30,000 cases were reported to the WHO. Reported cases increased more than 10-fold with the beginning of the Latin American epidemic in 1991.

In 1994, the number of cases (384,403) and countries (94) reporting cholera was the largest ever registered at the WHO.

Even Europe experienced a 30-fold increase in cholera from 1993-1994, with reported cases increasing from 73 to 2,339 and deaths increasing from 2 cases to 47.

According to the WHO, the number of cases surged again in 2005. From 2005 to 2008, 178,000-237,000 cases and 4000-6300 deaths were reported annually worldwide.

[8] However, the actual global burden is estimated to be 3-5 million cases and 100,000-130,000 deaths per year. The 2008 outbreak in Zimbabwe lasted longer than a year, with more than 98,000 cases and more than 4000 deaths.

[9] Outbreaks in Guinea and Yunnan province in China contributed to this increase. [10, 11]

The V cholerae O139 serogroup (also known as Bengal), which emerged from Madras, India in October 1992, has spread throughout Bangladesh and India and into neighboring countries; thus far, 11 countries in Southeast Asia have reported isolation of this serogroup. Some experts regard this as an eighth pandemic.

In mid-October 2010, a cholera epidemic broke out in Haiti, which has been worsened by heavy rains in 2011. As of June 20, 2011, 363,117 cases of cholera and 5,506 deaths have been reported.

[12] The epidemic is the first in Haiti in at least a century, and the source may have been a United Nations peacekeeping team from Nepal that came to Haiti after the catastrophic earthquake that hit the Caribbean nation on January 12, 2010. [13, 14]

Analyses performed by US and Haitian laboratories indicate that the strain involved in the outbreak is V cholerae El Tor O1 from the ongoing seventh pandemic predominant in South Asia . This may have consequences beyond Haiti, since this strain is more hardy and virulent, with an increased resistance to antibiotics. [15]

In nonendemic areas, the incidence of infection is similar in all age groups, although adults are less ly to become symptomatic than children. The exception is breastfed children, who are protected against severe disease because of less exposure and because of the antibodies to cholera they obtain in breast milk.

Source: https://emedicine.medscape.com/article/962643-overview

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