Cholera is an acute diarrheal infection that is caused by ingesting food and water contaminated by bacteria Vibrio cholerae.
Signs and symptoms of cholera infection include a rapid onset of massive diarrhea (rice water appearance), dehydration, vomiting, irritability, low blood pressure, and rapid heart rate amongst others.
Maintaining adequate hydration through oral or iv rehydration solutions (ORS and Ringer lactate solution) is the cornerstone approach of the treatment. Antibiotics are prescribed in severe cases once the hydration status is maintained.
Preventive measures include maintaining proper hand hygiene, drinking safe water and consuming non-contaminated foods. Oral cholera vaccine is also available but its use is usually limited to areas of cholera outbreaks.
Cholera is caused by a bacteria called Vibrio cholerae. There are approximately 200 strains of this bacteria. However, only two strains i.e O1 and O139 are known to be associated with cholera outbreaks. Both strains cause the same level of illness.
The bacteria are usually found in water that is contaminated with feces of an infected person. These bacteria are also found in the rivers that have saline water as they grow best in the presence of salt.
Cholera can be transferred from person to person by infected fecal matter entering the mouth or via water or food contaminated with Vibrio cholera bacteria.
Drinking water from sources such as unprotected wells, boreholes, and standpipes contaminated by feces during transportation or supply
Food, drinks, and ice made from contaminated water
Cooking and eating in utensils washed in contaminated water
Food that is stored for a long period of time at room temperature
Seafood especially crustaceans and shellfish grown in contaminated water
Raw fruit and vegetables that are irrigated with water containing human waste or rinsed with contaminated water
Cholera usually does not spread through direct physical contact. However, during outbreaks, it becomes highly contagious. It can spread indirectly and directly due to widespread fecal contamination of food, water, and items like contaminated bedding, clothing, utensils etc.
All individuals are not affected by the bacteria as the majority are killed by gastric acid. In case, bacteria survive, it forms colonies in the small intestine. These colonies produce cholera toxin which is responsible for most of the symptoms.
Cholera is asymptomatic in most of the individuals. However, even the asymptomatic individual can shed the bacteria into the environment through their feces for up to 10 days.
The majority of individuals who develop symptoms often have mild to moderate manifestations. The incubation period (the period between exposure to an infection to the appearance of the first symptom) can range from 12 hours to 5 days.
The classical symptom of cholera is massive and smelly diarrhea which is termed as “rice water stool”. The term is coined due to its similarity with the water in which rice is washed.
The various signs and symptoms of cholera infection include:
Acute watery diarrhea
Fishy smell from stools
Thirst
Leg cramps
Restlessness or irritability
Muscle cramps
Sleepiness and Tiredness
Dry mouth
Wrinkled skin
Rapid deep breathing
Rapid heart rate
Fever (rarely seen and indicates some secondary infection)
Hypoglycemia (mostly observed in children)
Low blood pressure
Other signs and symptoms that may occur in severe cases, include the following:
Sunken eyes
Low or no urine output
Skin pinch goes back very slowly
Lethargic or unconscious
Absent or weak pulse
Respiratory distress
Seizures
Shock
Here are some tips that help prevent dehydration in diarrhea!
Several social, environmental, and biological risk factors can increase the risk of cholera. They are discussed as follows:
Lack of access to clean water and poor disposal facilities of feces increases the risk of cholera transmission.
Approximately 97% of cholera cases are seen in countries having the lowest level of water and sanitation services in the year between 2010 to 2021.
Open-air defecation is associated with an increased risk of surface water contamination and hence more risk of waterborne diseases like cholera.
People using improved (piped household, protected well or spring, or collected rainwater) water supply is at a lesser risk of contracting cholera.
The risk of contracting cholera is high during monsoons. This is because of the contamination of drinking water by sewage or polluted water bodies.
Here are some common monsoon diseases according to their modes of transmission with invaluable monsoon health tips to keep in mind.
Avoiding handwashing with soap and water after toileting, before eating, and during handling food increases the risk of transmission of cholera bacteria.
Here are 5 simple hand hygiene tips.
Cholera bacteria are not able to survive in the acidic environment of the stomach. So, individuals that are on any acid-neutralizing therapy such as proton pump inhibitors and antihistamines are at higher risk of infection. Such medications are also known to be associated to increase the severity of symptoms.
Individuals who consume raw or partially cooked seafood, crabs or shellfish, dried fish, and seafood salad have more chances of contracting cholera.
Here are some fish oil supplements that help fulfilling your needs without increasing the risk of waterborne disease.
Studies suggest that bottle-fed infants and children are more prone to infection than ones breastfeeding. This is due to the lack of exposure to contaminated bottle feedings for breastfed infants. Breastfeeding also provides protective functions that boost immunity to fight infections.
Most cases of cholera are seen in infants aged 6 to 11 months who are on their weaning journey.
Individuals having a condition called achlorhydria – the absence of hydrochloric acid in digestive stomach juices are more prone to contracting cholera. This is because cholera bacteria grow rapidly in a low acidic environment.
The deficiency of Vitamin A is also associated with an increased risk of cholera.
Studies suggest an increased risk of infection in people with HIV due to low immunity.
People with low incomes are more prone to cholera due to a lack of access to clean water.
People are at high risk of cholera include:
Healthcare personnel treating cholera patients
Cholera response workers
Travelers in an area of active cholera transmission
Did you know?
There is a strong link between cholera and the human O blood group. The blood group O does not increase the risk of cholera but it impacts the severity of the disease. This association is proved by several previous outbreaks. In 1991 during an outbreak in Peru, the number of hospitalized patients was more with blood group O. Similarly, the Ganges delta has very less cases of cholera during outbreaks due to the low prevalence of people with blood group O.
The diagnosis of cholera is important as it may turn into a widespread outbreak. It cannot be distinguished from any other infection-causing watery diarrhea without testing a stool sample.
It is the most widely used method for the diagnosis of cholera. In this, stool samples are incubated with a solution that isolates the bacteria from it. The appearance of yellow clumps indicates cholera.
The exact strain of bacteria is identified through further testing. This confirmatory test is helpful in differentiating cholera from other bacterial, protozoa, or viral causes of dysentery.
It involves an examination of stools under a dark field microscope. It is a rapid method. The vibrio-shaped cells with motility indicate cholera bacteria.
This test is often used in endemic areas. It involves placing a dipstick strip into a sample of stool. The two red lines on the dipstick confirm the presence of cholera. It takes between 2 and 15 minutes for the test to make a diagnosis.
The sensitivity and specificity of this test is not optimal. That is why, the fecal specimens should always be confirmed using culture-based methods.
Cholera is a preventable disease. There are several measures that can be taken at an individual and community level to prevent the outbreaks.
Ensure safe drinking water
Drink only filtered or boiled water
Use filtered or boiled water to prepare food, brush teeth, and make ice
Avoid using water bottles without a seal
Store water in a clean and covered container
Maintain hand hygiene
Cholera can be prevented by following basic hand hygiene. It is advised to thoroughly wash the hands with soap and water:
After using the washroom
Before, during and after preparing food
Before and after eating food
Before and after feeding your children
After changing your child’s diaper or washing their stools
After taking care of someone suffering from cholera
Note: In case soap and water are not available (as in traveling), alcohol-based hand rub with at least 60% alcohol can be used.
Buy sanitizers and hand wash from the comfort of your home.
Be cautious while using a washroom
Use toilets to get rid of the feces instead of open defecation
Dispose off the used diapers of children in toilet
In case a toilet is not available, pee or poop at least 30 meters away from any body of water.
Cook and consume food vigilantly
Prepare food in filtered or boiled water
Wash fruits and vegetables with filtered or boiled water
Consume fruits and raw vegetables after peeling
Cook food thoroughly especially seafood such as shellfish that has the maximum chances of contamination.
Eat hot food
Maintain cleanliness
Clean kitchen surfaces and utensils thoroughly with soap and water
Use kitchen utensils and surfaces to cook food after drying
Wash clothes 30 meters away from drinking water sources
Disinfect any stool contaminated surfaces with household bleach
A multifaceted community approach involving the following helps to mitigate the risk of cholera:
Implementing WaSH Services
Almost all cases of cholera arise due to poor access to safe drinking water and inadequate sanitation. WaSH is an acronym that stands for water, sanitation and hygiene. Availability of adequate and safe water and effective solid and liquid waste management plays a major role in decreasing the risk of contracting cholera.
Promoting surveillance
Since cholera is a highly infectious disease, close monitoring of the cases by the government agencies at local level helps in preventing the outbreaks. It should be a part of a disease surveillance system that involves the sharing of information at global level.
Any clinically suspected individual should be tested for cholera. Detection can be done using rapid diagnostic tests (RDTs) where positive cases indicate a cholera alert. It aids as a tool to control the cases by implementing the preventive strategies early.
Engaging community
The local or central government should launch effective and engaging programmes with an aim to prevent cholera at mass scale. People and communities are a part of the process of developing and implementing strategies.
The aim of the programmes are educating people about the:
Basic hygiene measures such as handwashing with soap
Sanitation interventions such as safe disposal of feces of the children
Safe preparation and handling of food
Risk and symptoms of cholera
Funeral practices for individuals who die from cholera to prevent infection among attendees.
Provision of Vaccination
The cholera vaccines are available in oral dosage form and denoted as oral cholera vaccine (OCV). The World Health Organisation (WHO) suggests using these vaccines in the cholera endemic areas. All three vaccines require two doses for full protection.
Dukoral: This vaccine is given along with a buffer solution. It can be given to all the individuals that are over 2 years of age. The time duration between the two doses is 7 days to 6 weeks. This vaccine (2 doses) provides protection for 2 years.
Shancol and Euvichol: They have the same composition. Both of these vaccines are given without a buffer solution. Individuals over one year of age can take this vaccine.
While, a two-dose OCV, has obtained license for use in India, mass vaccination covering the entire population in the country has not been implemented as of yet. This is due to factors like
Cholera has a tendency of localized outbreaks
Mortality due to cholera has considerably reduced over time due to increasing use of oral rehydration salt solution
Individuals should consult the doctor immediately in case of any symptoms of watery diarrhea or returning from any cholera-endemic country.
The doctors that might help include:
General physician
Internal medicine specialist
Gastroenterologist
Pediatrician
A general physician will examine your symptoms and initiate treatment.
In case of severe cases, they may refer you to an Internal Medicine specialist who provides comprehensive care for adult patients, managing complex cases and addressing underlying health conditions.
Gastroenterologists can also be consulted as they have expertise in diagnosing and treating gastrointestinal disorders like cholera.
A pediatrician can be consulted for medical treatment and preventive healthcare services for children and adolescents.
The success of cholera treatment depends upon the time to initiate the treatment. Prompt treatment reduces the risk of severe dehydration and its complications.
The main aim of the therapy is to restore the hydration status of the patient, combat infection and support overall recovery.
Interesting fact!
The approximate amount of ORS (in milliliters) needed over 4 hours can also be calculated by multiplying the patient’s weight in kg by 75.
Explore our wide range of oral rehydration solutions (ORS).
The common examples of antibiotics used are
In case of antibiotic resistance, the following antibiotics may be prescribed
The antibiotic therapy is usually given for about 3-5 days.
Note: Tetracycline is not recommended in pregnant women and children under 5 years of age because it causes permanent discolouration of teeth.
4. ZincIn cholera, zinc deficiency can lead to reduced water and electrolyte absorption. Therefore, zinc plays an important role in recovery from the symptoms. Zinc combined with ORS reduces the duration, severity, and recurrences of episodes of diarrhea.
It includes taking a high-energy diet immediately after initial restoration of fluids. It helps in preventing malnutrition and several other complications such as hypokalemia (reduced level of potassium) and hypoglycemia (low blood glucose).
Most of the complications develop due to severe volume depletion in the body. The fluid loss can reach up to 1 liter per hour in adults and 20 ml/kg/hr in children. This can lead to complications like:
Hypovolemic shock
Metabolic acidosis (build up of acid in the body due to imbalance in the acid base balance as a result of electrolyte loss)
Hypotension (low blood pressure)
Hypoglycemia (low blood glucose)
Keep a tab of your blood glucose from the comfort of your home.
In rare cases, the severe hypotension can even lead to:
Kidney dysfunction
Persistent vomiting can lead to aspiration pneumonia (condition in which food or liquid is breathed into the airways of lungs, instead of being swallowed)
Escherichia coli infection
Salmonellosis
Shigellosis
Rotavirus infection
Stool culture
Dark Field microscopy
Dipstick test
Rehydration: Oral rehydration solution and I.V. fluids
Antibiotics: Tetracycline, Doxycycline, Azithromycin, Ciprofloxacin, and Erythromycin
Zinc
Nutritional interventions
General physician
Gastroenterologist
Internal medicine specialist
Pediatrician
