Cholera - Vibrio cholerae infection. Section Navigation. Facebook Twitter LinkedIn Syndicate. Illness and Symptoms. Minus Related Pages. A physician checking a patient for dehydration. Person washing hands over a bucket of water. To receive email updates about this topic, enter your email address: Email Address.
What's this? Vibrio cholerae is a highly motile bacterium with modest nutritional requirements whose natural reservoirs are found in humans and in certain cases the environment. The disease is caused by ingesting contaminated water or food.
Man plays both the role of culture medium and means of transport for V. Diarrheal stools, massively contaminated by V. The incubation period, from a few hours to 5 days, and the healthy carriers, enable the transport of V.
The main factors that encourage cholera transmission are socio-economic status and living conditions of populations. Densely concentrated populations in areas with poor hygiene facilitate the emergence and development of cholera outbreaks.
Colony of the pathogenic cholera bacterium, Vibrio cholerae, possessing blue areas, indicating the successful artificial fusion of the two chromosomes to result in a single chromosome strain. Scientists from the Institut Pasteur and the Wellcome Trust Sanger Institute, in collaboration with several international institutions, recently published a landmark study in the journal Science.
They traced the history of cholera outbreaks in Africa, Latin America and the Caribbean over the past 60 years. Their research revealed that the cholera bacterium had been introduced at least 11 times into Africa over a period of 44 years, always from Asia, and that human populations were the main vectors for disease dispersal throughout Africa.
These findings show that cholera was not only introduced into Africa in before subsequently taking up residence there, but is repeatedly introduced on a regular basis. Starting from two prime zones of introduction in West Africa and East Africa, epidemics spread along preferential routes to persistence zones such as the Lake Chad basin or the Great Lakes region. The areas of Africa most susceptible to the introduction of cholera will have to be targeted more specifically in order to stem the cholera waves before they sweep the rest of the continent," point out the researchers.
This research was based on a unique collection of cholera vibrio strains, formed by the Institut Pasteur and kept there for nearly 50 years the Institut Pasteur has long-standing expertise in cholera research — see below in "The Vibrios and Cholera CNR at the Institut Pasteur" , as well the Wellcome Trust Sanger Institute's the genome collection — enabling the scientists to cover not just Africa but also other world regions.
In a second study, the team focused on Latin America, where epidemic cholera reemerged in alongside sporadic cases of low-level disease.
This revealed that the risk of large-scale outbreaks varies depending on the V. The massive epidemics seen in Peru in the s and Haiti in were caused by the Asian pandemic strain, whereas the sporadic cases in Latin America arose from local strains.
All of these studies demonstrate the added value of whole-genome sequencing of V. Our research illustrates the benefits of combining epidemiological and laboratory data during investigations of epidemics, and lends weight to the message recently issued by the WHO's Global Task Force on Cholera Control [see below] to public health practitioners, which recommends systematically combining these two approaches to improve epidemic management.
Urgent action is needed to protect communities, prevent transmission and control outbreaks. Find out more. Read the press release. Genomic analysis of more than 1, strains of Vibrio cholerae by scientists from the Institut Pasteur and the Wellcome Trust Sanger Institute, in collaboration with several international institutions, revealed for the first time the link between the different outbreaks of cholera since Their findings were published in the journal Science on November 10, The world is currently witnessing its seventh cholera pandemic.
The first six pandemics killed millions of people after the infection spread from its original reservoir in the Ganges delta in the 19th century. The seventh pandemic began in South Asia in , reaching Africa in and America in Recent studies, in which the Institut Pasteur has been actively involved, have proven this historical trajectory and demonstrated the link between all the major cholera outbreaks. In May , the World Health Assembly recognized the "reemergence of cholera" as a global public health problem and adopted a resolution to improve cholera control.
At that time the UN stated that "with increasing populations living in peri-urban slums and refugee camps, as well as increasing numbers of people exposed to the impacts of humanitarian crises, the risk from cholera will likely increase worldwide". The events currently unfolding in Yemen have tragically proved it right.
While the use of oral cholera vaccines can play an effective role in helping control cholera, improving access to drinking water and basic sanitation services in many countries — together with the efforts of local communities — are vital in the fight against this disease and many other waterborne infections.
Drinking contaminated water or consuming contaminated food is the most common way you can be exposed to the O1 or O bacteria. O1 and O bacteria are most common in places with poor water treatment, sanitation, and hygiene practices, according to the CDC. In addition, although there are no other animals besides humans in which the bacteria can reproduce and spread, Vibrio cholerae frequently attach to the shells of crabs, shrimps, and other shellfish.
As a result, raw and undercooked shellfish have been sources of cholera infections in the United States. Raw fruits and vegetables are also a common source of cholera in areas where the disease is found, because crops may be treated with contaminated water or manure fertilizers.
Similarly, in regions where cholera is common, grains such as rice that are contaminated after cooking and kept at room temperature for several hours can also contain cholera bacteria.
Everyone is at risk for cholera though infants can get immunity from a nursing mother who has previously had the infection.
In general, cholera is common in areas where a safe supply of drinking water is difficult to maintain, including refugee camps, impoverished countries, and areas impacted by famine, war, or natural disasters. In addition, research indicates that people with type O blood are twice as likely to develop cholera compared with people with other blood types — though it's unclear why. Cholera also spreads easily.
A person infected with the bacteria can cause a one-million-fold increase in Vibrio cholerae numbers in the environment through a single diarrheal episode, according to the National Institute of Allergy and Infectious Diseases. In addition, because people with cholera shed bacteria in their stool for 7 to 14 days, they can infect anyone who comes in contact with their feces, or water contaminated by it.
In areas where the infection is common, cholera may be recognized by its symptoms, but the only way to confirm the diagnosis of cholera is to identify the O1 or O bacteria in a stool sample. Without treatment — usually rehydration — up to half of those infected with cholera will die. Risk of death is higher in children, pregnant women, and the elderly. Generally, the risk for death from cholera has declined globally in recent years because of enhanced access to healthcare, and improved sanitation and education.
With effective rehydration, less than 1 percent of those infected with cholera die from it. As noted above, symptoms usually appear within two or three days of exposure to the bacteria. In mild or uncomplicated cases of cholera, symptoms subside on their own within three to six days of onset and the bacteria disappear from your system within two weeks. In very severe cases of dehydration, patients will need intravenous fluid replacement. Up to 80 percent of cases can be successfully treated with ORS.
In the most severe instance of cholera, treatment may require intravenous IV fluid replacement. In some cases, your doctor may recommend the use of prescription antibiotics usually tetracycline or doxycycline to help reduce the severity of symptoms and speed up the recovery time. In addition, zinc supplements may help decrease the duration of diarrhea in children under 5 years old with cholera, according to the WHO. In general, research on the use of alternative and complementary therapies in cholera is limited.
But a study published in June in BMC Complementary Medicine and Therapies suggests that extracts from the rose family of plants — traditionally used as a remedy for diarrhea in some parts of eastern Europe — may help slow the growth of the bacteria and inhibit the cholera toxin.
Cholera isn't endemic to the United States per the WHO, a cholera-endemic area means that confirmed cholera cases were detected there during the last three years with evidence that transmission was local. Nearly all cases of cholera in the United States are acquired when people travel internationally. You can avoid getting the illness when traveling abroad with the following measures:. In addition, the U. Food and Drug Administration FDA has approved a single-dose live oral cholera vaccine called Vaxchora for adults ages 18 to 64 who are traveling to an area of active cholera transmission.
The vaccine is designed to protect against cholera caused by O1 strains of Vibrio cholerae. Although most cases of cholera are mild — particularly if treated — the infection can be fatal. Other complications of cholera include:. If cholera makes you too ill to eat, dangerously low levels of blood sugar can occur, causing seizures, loss of consciousness, and death. Children are at increased risk for this complication.
0コメント