Cholera remains a global public health threat and is an indicator of inequity and lack of social development. Researchers have estimated that each year there are 1.3 to 4.0 million cases of cholera and 21,000 to 143,000 deaths worldwide due to the infection. During the IXX century, cholera spread worldwide from its original reservoir in the Ganges delta in India. Seven successive pandemics killed millions of people on all continents. Cholera is now endemic in many countries. Cholera can be endemic or epidemic. A cholera-endemic area is one in which confirmed cases of cholera have been detected in the past 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 occur regularly. In cholera endemic countries an outbreak may be seasonal or sporadic. In a country where cholera does not occur regularly, 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 usually no cholera. Cholera transmission is closely linked to inadequate access to drinking water and sanitation facilities. Typical risk areas include peri-urban slums and IDP or refugee camps, where minimum requirements for clean water and sanitation are not met. The number of cholera cases reported to WHO has continued to be high in recent years. In 2017, 227,391 cases were reported from 34 countries, including 5654 deaths. The discrepancy between these figures and the estimated burden of the disease is due to the fact that many cases go unreported due to limitations in surveillance systems.
Cholera is an acute, diarrheal disease caused by infection of the intestine with the bacterium Vibrio cholerae and is spread by ingestion of contaminated food or water. The disease has an incubation period ranging from 24 to 72 hours to up to 5 days. Infection is often mild or symptomless, but can sometimes be severe and life-threatening. About one in ten (5-10%) of infected people will present with severe cholera, which in the early stages includes:
- profuse watery diarrhea, sometimes described as "rice-water stools."
- vomiting
- accelerated heartbeat
- loss of skin elasticity
- dry mucous membranes
- low blood pressure
- thirst
- muscle cramps
- restlessness or irritability
The disease causes a wide spectrum of symptoms: 75% of those infected show no symptoms at all, up to the most severe cases that result in death.
In the most severe forms, especially if left untreated, continuous fluid loss can result in dehydration, shock to death. The profuse diarrhea produced by patients with cholera contains large amounts of infectious Vibrio cholerae bacteria that can infect others if ingested, and when these bacteria contaminate water or food they will lead to further infection. Dispose of human waste appropriately to prevent the spread of cholera. People caring for cholera patients can avoid contracting disease by washing their hands after touching anything that may be contaminated and properly disposing of contaminated items and human waste. Infected people, if treated promptly, can recover quickly and there are usually no long-term consequences. People with cholera do not become carriers of the disease after their recovery, but they can be re-infected if re-exposed.
Beyond the clinical aspect, the diagnosis is confirmed by isolation of the bacterium in fecal cultures or rectal swabs.
Treatment of cholera relies mainly on immediate replenishment of fluids and minerals. In most cases oral rehydration is successful, but in more severe cases intravenous fluid balancing (up to 4-6 liters) is necessary.
The use of antibiotics, such as tetracycline or ciprofloxacin, is recommended, which can reduce the intensity of symptoms.
There is a cholera vaccine that is a safe and effective weapon against transmission of the bacterium in endemic areas. In addition, it is always important to protect yourself with some simple rules:
- Drink safe water
- Bottled water with seals and bottled carbonated drinks are safe
- Use safe water to brush your teeth, wash and prepare food, and make ice
- Clean food preparation areas and kitchen utensils with soap and safe water and let them dry completely before reusing them
- If you do not have bottled water, bring water to a boil for at least 1 minute
- To treat water with chlorine, use one of the certified chlorine treatment products and follow the instructions
- Wash your hands with safe water and soap
- Before eating or preparing food
- Before feeding your children
- After using the toilet
- After caring for someone who is sick
- Use the toilet
- Use latrines or other sanitation systems, such as chemical toilets, to dispose of feces
- Wash hands with soap and safe water after defecating
- Clean latrines and surfaces contaminated with feces using a solution of 1 part household bleach to 9 parts water
- Cook safely
- Cook, bring to a boil, peel
- Avoid raw foods - always wash and peel fruits and vegetables
- Personal and environmental hygiene
Given the oro-fecal mode of transmission, which is often carried by contaminated food and water sources, primary prevention for cholera infection involves the management and purification of water sources, sewage system operation, and food safety. Health education of communities, especially the most vulnerable ones, with respect to hygienic maneuvers during food preparation and intake, such as washing hands with soap before starting to handle food, is critical in epidemic control. Preventing and controlling cholera requires interventions outside the health sector, and it is necessary to engage with partners in other sectors. The development and implementation of multisectoral cholera control plans is a useful mechanism for bringing together all relevant sectors and creating lines of communication and coordination that are useful beyond cholera control.