Cholera generally occurs in areas with poor sanitation, especially where sewage contamination of water sources occurs. Improved water and sewer infrastructure and water safety can drastically reduce cholera transmission.
Taking advantage of the inefficient infection properties of V. The specific treatments, vaccines, and diagnostics used in cholera monitoring and control strategies are discussed in more detail below.
The recommended treatment for cholera infection is oral or IV rehydration. As antibiotics work on the bacteria, but not the secreted toxin causing the diarrhea, symptoms do not stop immediately and the use of rehydration in conjunction with antibiotics remains key to preventing death. Injection of inactivated whole bacteria for protection against cholera has been in use since the s.
Since that time, newer oral inactivated whole cell vaccines have been developed. The vaccine uses a combination of formalin and heat-killed bacteria with recombinant cholera toxin B protein.
Dukoral only protects against O1 serotype V. The cross protection is attributed to the recombinant cholera toxin B included in the vaccine, which has high homology with a toxin from ETEC. Due to the short duration of protection, this vaccine is primarily used in travellers rather than people living in endemic countries. Shanchol received WHO prequalification in November These vaccines have several advantages over Dukoral, including protection against both O1 and O serotypes, a longer duration of protection in children, and a cheaper cost of production.
There are several unmet needs for cholera vaccine development including 1 developing new vaccines that increase the duration of protection and can be given as single dose, and 2 more extensive testing to evaluate the value of using the current cholera vaccines to prevent or manage cholera outbreaks.
Outbreak monitoring is important both in endemic countries and in non-endemic countries after major natural or man-made disasters. Disasters can destroy sanitation infrastructure making disaster victims more susceptible to outbreaks. Monitoring for cholera outbreaks occurs through a combination of monitoring water sources, primarily for phytoplankton blooms or increased levels of V. Patient monitoring is primarily done through bacterial culture of stool samples although rapid diagnostic tests are also available to look for the presence of O1 or O strain lipopolysaccharides.
Over the next 20 years cholera caused a series of serious epidemics, killing tens of thousands of people in England alone. Back then very little was known about how infectious diseases spread or even what infectious diseases were.
However, the investigations of John Snow were about to challenge these ideas. A magazine illustration from showing the unsanitary and crowded conditions of London slums. Image credit: Wellcome Library via Wellcome Images. He was particularly fascinated with how infectious diseases, like cholera, were spread. Since beginning his medical training, he was always keen to investigate water as a vehicle for transmitting infectious disease.
In addition to this, water from the Thames was commonly bottled and delivered to pubs and other businesses for consumption! John Snow recognised this and suspected that sewage could be contaminating the water supply and spreading cholera, and probably many other diseases, around the city.
In September a particularly severe outbreak of cholera hit the Soho area of London, close to where John lived. He took the opportunity to find the source of the outbreak, once and for all. He worked around the clock to track the infection by examining hospital and public records. John constructed a map below showing the location of various water pumps around the city and where deaths from cholera were clustered. He showed the number of deaths at each address as a series of horizontal lines, stacked up like a pile of bodies in the street.
At that time the pump not only provided water to many households in the surrounding streets, but also supplied a number of businesses in the area. Some groups of people in the area had managed to avoid cholera despite living and working near the pump so John investigated why this was. He found one group of men working in a brewery on Broad Street who had remained healthy by avoiding drinking water from the pump and instead sticking to their own beer.
Although unbeknown to them at the time, the fermentation process kills the cholera bacteria so drinking beer and gin was actually much safer than drinking water back then!
John Snow's cholera map focused on the broad street water pump. On 7th September John took his findings to the town officials and convinced them to take the handle off the Broad Street water pump. Although they initially refused his request, after removing the handle the outbreak of cholera almost immediately dissipated.
The German physician Robert Koch identified the cause of cholera, the bacterium Vibrio cholerae. A few decades later, the German physician Robert Koch identified the cause of cholera, the bacterium Vibrio cholerae. John is now widely credited with establishing the field of epidemiology. To mark the importance of his discovery, the Broad Street pump is on permanent display in the London School of Hygiene and Tropical Medicine.
Many people think that the cholera story ends there, but it is a still very much a major public health issue. Today, cholera causes millions of cases of diarrhoea and hundreds of thousands of deaths every year. Even in the UK there are about 12 cases of cholera reported every year, although these are generally associated with overseas travel to developing countries. Cholera—modern pandemic disease of ancient lineage. Emerg Infect Dis.
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Microbiological examination of sachet water due to a cholera outbreak in Ibadan, Nigeria. Open J Med Microbiol. When urban taps run dry: sachet water consumption and health effects in low income neighborhoods of Accra, Ghana.
Health Place. Effects of sachet water consumption on exposure to microbe-contaminated drinking water: household survey evidence from Ghana. An evolving choice in a diverse water market: a quality comparison of sachet water with community and household water sources in Ghana. Am J Trop Med Hyg. Microbiological and chemical quality of packaged sachet water and household stored drinking water in Freetown, Sierra Leone. PLoS One. Informally vended sachet water: handling practices and microbial water quality.
Funerals during the cholera epidemic in Guinea-Bissau, West Africa: the need for disinfection of bodies of persons dying of cholera. Epidemiol Infect. BMC Public Health. Estimation of packaged water consumption and associated plastic waste production from household budget surveys. Environ Res Lett. The role of packaged water in meeting global targets on improved water access. J Water Sanit Hyg Dev. Legros D. Approximately 1 in 10 people who get sick with cholera will develop severe symptoms such as 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 in foods that have been contaminated by feces poop from a person infected with cholera bacteria. Cholera is most likely to occur and spread in places with inadequate water treatment, poor sanitation, and inadequate hygiene.
Cholera bacteria can also live in the environment in brackish rivers and coastal waters. Shellfish eaten raw have been a source of infection. Rarely, people in the U. A person can get cholera by drinking water or eating food contaminated with cholera bacteria.
In an epidemic, the source of the contamination is usually the feces of an infected person that contaminates water or food. The disease can spread rapidly in areas with inadequate treatment of sewage and drinking water. The infection is not likely to spread directly from one person to another; therefore, casual contact with an infected person is not a risk factor for becoming ill. Cholera infection is often mild or without symptoms, but can be severe. It usually takes days for symptoms to appear after a person ingests cholera bacteria, but the time can range from a few hours to 5 days.
Persons living in places with unsafe drinking water, poor sanitation, and inadequate hygiene are at the highest risk for cholera. If you think you or a member of your family might have cholera, seek medical attention immediately.
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