What is Cholera?
Cholera is a severe illness that triggers intense diarrhea and is caused by Vibrio cholerae bacteria. This disease affects around four million people globally every year. Cholera leads to loss of lots of fluids and imbalances in electrically charged minerals, which in severe cases can cause a drop in blood pressure and even death. This disease affects your digestive system and is spread when people swallow bacteria present in human feces. The severity of the illness can vary, but the most important step for recovery is immediately replacing the fluids and minerals that are lost.
What Causes Cholera?
Vibrio cholerae is a particular type of bacteria that is often found in developing countries. It’s a bacteria that’s shaped somewhat like a comma and changes depending on the environment. There are two types of it that cause outbreaks. The O1 type is the one behind more recent outbreaks, while the O139 type sometimes causes outbreaks, notably in Asia. Importantly, there’s no difference in how they cause disease.
Vibrio cholerae is known to be found in certain foods, particularly shellfish, and in water that hasn’t been properly cleaned. It usually spreads when bacteria in the feces of an infected person are ingested, so it’s more commonly found in areas where food and water aren’t properly cleaned.
To get the disease, a person usually needs to ingest a large amount of the bacteria. There are also certain factors that make a person more likely to get infected. These include:
* Taking certain drugs like proton-pump inhibitors and antihistamines
* Having type 0 blood
* Living in areas with poor sanitation
* Living in overcrowded conditions
* Having previously had a vagotomy, a surgery to remove part of the stomach
* Being infected with Helicobacter pylori, a bacteria that can cause stomach ulcers.
Risk Factors and Frequency for Cholera
Cholera is a disease that affects millions of people worldwide. Every year, there are about four million cases, and more than 140,000 people die from it. One of the big reasons this happens is because almost 1.8 million people across the globe get their drinking water from sources that are contaminated with human wastes, which could contain the cholera bacteria. This issue is particularly severe in developing countries where there aren’t proper sanitation and water filtration systems.
Currently, there are around 50 countries, mainly in Asia and Africa, where cholera is a persistent problem. The number of cases often changes with the seasons, usually increasing during the rainy season. From time to time, the disease can also spread more widely and cause outbreaks in other parts of the world like South and Central America. When a region experiences a breakdown in their hygiene and health services, it can give rise to cholera epidemics.
Signs and Symptoms of Cholera
Cholera is a disease that can have a variety of symptoms. Some people may not show any symptoms at all, while others can have severe diarrhea. The most common symptoms include diarrhea, belly pain, and vomiting. A distinctive sign of severe cholera is the rapid and significant loss of body fluids and electrolytes, typically resulting in a diarrhea that is often described as having a “rice water” appearance, which can contain bile and mucus. In adults, the output of this diarrhea can be as much as one liter every hour. For children, it can be as much as 20 cc per kg of body weight per hour.
The excessive loss of body fluids can lead to a condition called hypovolemia, which is characterized by typical signs of dehydration such as dry mouth, cool skin, and skin that doesn’t bounce back when you pinch it. Circulation of blood to body tissues may also be inadequate, potentially leading to a build-up of lactic acid in the body. This can make someone breathe rapidly and deeply, a condition known as Kussmaul breathing. Additionally, imbalances in body salts such as potassium and calcium can occur, which can cause general muscle weakness and cramping.
- Diarrhea
- Abdominal discomfort
- Vomiting
- “Rice water” consistency stools, possibly mixed with bile and mucus
- Fluid loss symptoms: dry mouth, cool skin, decreased skin elasticity
- Fast and deep breathing (Kussmaul breathing)
- Generalized muscle weakness and cramping due to electrolyte imbalances
Testing for Cholera
If a person is suspected to have cholera, a diagnosis can often be made just by noting their symptoms, such as severe diarrhea, and knowing if they’ve been in an area where cholera is common. Often, lab tests are not needed before starting treatment.
However, if it’s necessary to confirm the diagnosis, doctors can do so by identifying the cholera bacteria in a sample of the patient’s stool. This can be done through a process called culture, where the bacteria are encouraged to multiply in the lab. Because cholera bacteria prefer a more basic environment, a high-pH medium is used to suppress other bacteria and let the cholera bacteria thrive.
There are also quick tests available that can detect certain antigens – substances that trigger an immune response – that are specific to the cholera bacteria in stool samples. In addition, simple tools like dipsticks or a type of microscopy can identify or visualize the cholera bacteria quickly.
Treatment Options for Cholera
Cholera treatment mainly involves swiftly restoring fluids in the body based on the amount lost due to the disease. If the patient has lost 5% to 10% of body weight, an oral rehydration solution should be taken. Research has shown that a rice-based type of this solution can actually lessen the length and severity of diarrhea. In urgent situations, a homemade solution can be made from a liter of water, six teaspoons of sugar, and a half teaspoon of salt. If the weight loss exceeds 10% or the patient is in a state of shock due to extreme fluid loss, intravenous fluids are necessary. In such cases, about 100 mL/kg of lactated ringers are administered during the initial three hours. Rapid and efficient fluid treatment of severe cholera cases can decrease the death rate from more than 10% to less than 0.5%.
When the patient’s fluid levels are back to normal, antibiotics can be started. The most commonly used antibiotics for cholera are tetracyclines. A single dose of 300mg for doxycycline or 500mg of tetracycline every 6 hours for 2 days has been shown to shorten the duration of the disease. Nonetheless, resistance is common in some areas, so alternative treatments often involve macrolides like erythromycin and azithromycin, or fluoroquinolones such as ciprofloxacin.
What else can Cholera be?
- Infection by E. coli bacteria
- Salmonella infection (commonly associated with food poisoning)
- Shigella infection (a cause of diarrhoea)
- Typhoid fever (a dangerous bacterial infection)
- Rotavirus infection (a common cause of childhood diarrhoea)
What to expect with Cholera
Without enough water, death rates can rise to over 50%. This is especially true for children, pregnant women, and older adults. However, total death rates have been going down thanks to improved healthcare access, better sanitation, and education.
Possible Complications When Diagnosed with Cholera
These are some serious complications that can result due to certain medical conditions, such as:
- Dehydration
- Acute tubular necrosis, a kidney condition
- Renal failure, i.e., kidney failure
- Severe hypotension, or very low blood pressure
- Death
Preventing Cholera
In regions where cholera is common, it’s crucial to teach people about the importance of personal hygiene, boiling drinking water, and improving cleanliness in their surroundings. Preventing cholera largely depends on strengthening public health measures such as proper disposal of sewage and providing clean drinking water. The cycle of cholera continues because often, contaminated water is used to wash fruits, vegetables, and even fertilize crops. Therefore, food handlers should also learn about maintaining personal hygiene and washing their hands correctly.
When it comes to preventing this disease in travelers, the key is ensuring clean water and sanitation. Travelers should be taught to avoid eating undercooked seafood, as well as raw fruits and vegetables. While it’s best to avoid tap water, if necessary, it can be filtered or boiled to lessen the chance of transmitting the cholera bacteria. In the US, there’s an oral cholera vaccine meant for adults between 18 to 64 who plan to visit a region where cholera is prevalent. Ideally, one should take this vaccine 10 days prior to traveling. Taking this vaccine separately from antibiotics helps in maintaining the effectiveness of the vaccine. It’s been observed that the vaccine prevents cholera in 80% of the cases three months after vaccination. There are also three similar vaccines available globally.
