Describe the epidemiological situation of cholera and its determinants in Nepal, Illustrate the principles of case management, Prevention and, control of cholera. 8 (2064) 4, Write short notes on: (2054), =a: Killed oral cholera vaccine - | * Cholera isan acute, infectious, diarrhoeal disease of the small intestine, caused by the bacterige Vibriocholera 01 (classic or EI tor) transmitted usually by the fecal contamination of food and water * Cholera is a disease of inequity—an ancient illness that today sickens and kills only the poorest and most vulnerable people. * The map of cholera is essenti of poverty, Every death from cholera is preventabis With the tools we have today, putting the goal of ending its public health impact within our reach, * Gholera can be controlled with’ a. multi-sector pbProach—including basic water, sanitation, and hygiene (WASH) Services, and oral cholera vaccines (ocvy, ially the same as a map Problem Statement Wada Ie tga ao * While safe drinking water and advanced sanitation ‘systems have made Ej and North Ameri Sholera, idesy-the disease still affects at Teast. 47 countries across the glol e, Tesulting In an ATEN ry Tes the globe, FEST TUMOR cases and 95,000 deaths per Year worldwide ih 2017, cholera continues to hit communities already made vulnerable by tragedies such as conflicts any id famines. Yemen currently faces Neues largest cholera outbreak with over Sones ‘Suspected cas 100__-deaths rotted since April2. Over 800 people have died of Sholera in Somalia sinee the beginning of the year, and over 500 in the DRC. Haiti has now reported ee Lnlion cases wi ,000-deaths-sinee— al ‘ Sholera endemic in Nepal and is responsible for wt PSH of Ul sctce dhatstes come ia eo thus constituting one of the major public health problem. * Nepal is at high risk of cholera outbreak as natural disasters like floods and landslides are common during the rainy season and about 80% of Population of the rural areas lack safe drinking water, proper sanitation and good personal hygiene despite proper knowledge, * Even in the cities there is lack of safe drinking water, Good sanitation facility and poor housing conditions despite good health services due to increase in urban Popullation density and inadequate supplies of safe drinking water, Every year there are cases of cholera in rural and urban areas and even in parts of countries which are | difficult to access Largest cholera outb 2009 where 30,000 c People lost their lives * In 2014, cholera outbreak was reported in Rautahat {2 feral region where 600 people were confirmed by laboratory diagnosis + Due to ina districts of mid and far chal 7537 cholera cases during FY 2073/74, Epidemiology reak occurred in Jajarkot in 'ases were of cholera and 500 ices-and facilities, hilly western region ape at risk for Were reported from hospitals (Geent Factors + Agent: * Causative organism: Vibrio cholarae ‘* Two serogroups: 1. V.cholarae 01: Two bit El Tor). 1. V. cholarae 0139 (confined to South East Asia) * Classical and El Tor varieties can be further classified into: Inaba, Ogawa (most common in Our region), Hikojima , { Vibrio is comma shaped, minute, lotypes (Classic type and bacillus, with. size (1-Smm) x (0.3-0.4mm), It is Gram {ve, aerobic, non-spore forming, actively motile (Darting or Scintillating movement) and flageliated bacillus, Resistance: + Vecholera are killed withi at 56 °C or within a few * Destroyed by coal tar dis Toxin Production: + Endotoxin: wall) in 30 minutes by heating seconds by boiling isinfectants (cresol) 'popolysaccharide 0 antigen (cel \ \ Exotoxin (enterotoxin):- Twounits A and Bare present - B unit adheres organism to mucosal membrane of jejunal epithelial cells - A unit is enzyme moiety and consists of Al and A2 where Al activates adenyl cyclase- cAMP pathway as a result water and electrolytes are secreted into intestinal lumen causing massive purging and watery diarrhea and AZ unit links Al and B. Reservoir of infection: Human being is only known reservoir (Case and carrier) Carriers can be pre-clinical, convalescent, healthy or chromic carriers Infective materials: Stools and vomit of case and carrier Infective dose: 10° organisms is required to produce clinical disease in normal person Period of commumicability: 7-10 days (cases) For convalescent carrier: 2-3 weeks For chronic carrier: Up to 10 years or more. Cholera carriers ° Atypes 2 Preclinical carrier: short duration (1-5 days) Bb. Comvalescest carrier: 2-3 weeks; who have not © Cholera tends to occur only when the absolute hnasnidity exceeds 19 mmiig vapor pressure. » Poor environmental sanitation © Contaminated water and food sam rransmissio® Modes AT ore reco-oral route, not onky through wate, but also . tteoughs contaminated food, frutts and vse avai il aU eee ee a — House flies act as mechanical vectors. ‘© Contaminated fingers and fomites also transm the disease. Predisposing Factors * Poverty, illiteracy, ignorance, poor standard of living with lack of sanitation. Incubation Period + Varies from a few hours to a few days (Average 1. days). Nature of Stool + ‘Rice-watery’ stools in cholera, caused by classic vibrios + Watery by Eltor vibrios. Clinical Features Majority of cases are mild or asymptotic and typicd features seen in severe cases as follows: a. Stage of Evacuation T)—>Y @ There is sudden onset of painless, profuse effortless, watery diarrhea followed by vomiting © Rice water stool pass as many as 40 stools pe day. b. Stage of collapse « There will be rapid onset of dehydration an collapse characterized by sunken eyes, hollow gacheeks, scaphoid abdomen, hypotension, hypo thermia, rapid, feeble and thready pulse, loss skin elasticity and hurried respirations. * Decreased output of urine indicates anuria am renal failure. * Kussmaul's type of respiration indicates acidosis Thus dehydration leads to acidosis, renal failu and death. . Stage of recovery © Patient may show the sign of clinic improvement Laboratory Investigations f stools of > This consists mainly of examination o cholera patient and water sample of the suspect source, vomitus and food samples. Methods of Collection of Stool i, Rubber catheter method: « Best method © A sterile rubber catheter of no. 26 to 28" lubricated with liquid paraffin and passed int the rectum for about 5 cm and stool is collected asterile.cual a ft «Transportation: McCartney bottle of 30mL capacity at the other end, containing holding (or transport) media (Venkataraman-Ramakrishnan medium or Alkaline Peptone water), 41, Rectal swab method: » A sterile rectal swab is dipped into the holding medium and then inserted into the rectum and a swab is taken, placed in the sterile plastic bag, tightly sealed and sent to the laboratory. Method of Collection of Water + About 1 to 3 liters of water is collected from the suspected source. and mixed with 10 percent of alkaline- peptone (A-P) water in the ratio of 9 volumes of water with 1 volume of A-P water, sealed and sent to the laboratory by the quickest mode of transport. Culture + Inthe laboratory, the stool specimen is inoculated into the enrichment medium, ie. potassium tellurite and incubated for 6 hours and then inoculated into the Bile Salt Agar or Meat Extract Agar and incubated for 24 to 48 hours. + If the stool sample is collected by rectal swab method, the culture media used in Cairy Blair media * V. cholerae usually appear as translucent, moist, smooth, raised and easily emulsifiable colonies of about 1 mm diameter. ‘The colonies are picked up and tested as follows: i. Gm staining: They are Gm -ve rods. ii, Hanging drop __ preparation: Sn eee iii. Dark field ijlumination: Look like shooting stars in adark sky 4 + iv, Serological test ¥. Biochemical examination: Fermentation with production of acid in sucrose and mannose but not arabinose is characteristic of V.cholerae. vi. Other tests: © Hemolytic test * Vogues-Poskure (V-P) test © Polymyxin B sensitivity test * Agglutination test Prevention and Control Bt Elimination of Reservoirs i Cases * Isolation in the hospital, till 2 to 3 consecutive stool culture report comes as negative. * Concurrent and terminal disinfection: Stools and Voritus to be disinfected with cresol. Characteristic * Chemotherapy: Erythromycin and azithromycin are drug of choice (tetracycline and ciprofloxacin may be used in susceptible areas). © Rehydration therapy (Orally or IV depending * upon the degree of dehydration). li. Carriers: © They are detected only by stool culture report and are treated accordingly. Blocking the Channel of Transmission # Since the disease cholera is transmitted by feco-oral route, the best way of blocking the channel is by construction of ‘Sanitation barrier’ ST Fluids Food Fruits and Feces vegetables Fomites Fingers Flies Sanitation barrier a Protection of Susceptibles ‘Immunization ‘Two types of vaccines are available against cholera- parenteral and oral vaccines a. Parenteral vaccine: «Heat killed, phenol preserved vaccine «Each dose of 0.5 mL contains 3000 million, killed organisms each, of Inaba and Ogawa serotypes of classical vibrios 01, providing cross immunity against Eltorvibriosalso * Primary immunization consists of 2 doses, each of 0.5 mL deep IM with an interval of 4 to 6 weeks * Half of this dose for children below 10 years ‘+ Infants need not immunized + Immunity is developed after about 15 days and lasts for hardly 5 to 6 months * Limitations: Use of this vaccine after the outbreak of cholera does not serve the purpose to control the epidemic because the individual i I PGmekeeec cece mc LIEBAAT y develops the antbsieD rer 15 day of immunization and since the incubation period of cholera is very short, the individual may develop the disease much before he develops immunity Oral vaccine: These are two types. 1, Killed whole cell V cholerae 01 in combination with a recombinant B-subunit of cholera toxin ~ For 2 6 years old Given orally in 2 doses with 27 days apart + for <6 years 3 doses are given ~ It confers 50 to’60 percent protection + Immunity lasts for 3 year 2. Live attenuated CVD 103-HgR vaccine + Itisa single dose vaccine + Confers 80 percent protection - Oral antibiotics are avoided for one week before and one week after the administration of live vaccine = Itisnolonger produced Health Education « This is the most effective prophylactic measure * The community is educated about the following point: i. Routes of transmission of consequences of dehydration ii, To avoid open-air defecation and to use sanitary latrines Iii. To use boiled and cooled water for drinking purposes iv. To use ORT with the onset of diarrhea y. To take prompt treatment for diarrhea vi. To adopt personal hygiene by washing hands with soap and water before handling food and after using toilet vil.To control house flies, by keeping the premises __— lean in and around the houses ines for control of cholera ) eso a - 2, Notification 3, Early case findings 4, Establishment of treatment centers 5. Rehydration Therapy 6. Adjuncts to Therapy: a. Adult: Doxycycline b. Children: TMP-SMX/Co-trimoxazole c. Pregnancy: Furazolidone d. Prophylaxis: Tetracycline cholera and 7. Epidemiological investigations 8, Sanitation measures 9. Chemoprophylaxis (DOC Tetracycline 500mg gy, for 3days, for children 125 mg) 10, Immunization 11. Health Education Differences between poisoning cholera and foog Precedes vomiting _ [Follows vomiting s|Absent Present Watery andnot [Offensive but Neve offensive lwatery "Projectile Follows diarrhea IViolent and distressing Precedes diarrhea Watery INever watery “|Secretion Never suppressed _|suppressed Constant and severe Occurs only in severe cases sis sub-normal is increased is absent is present [Acidosis [alkalosis |Acute watery diarrhea Acute bloody ldiarrhea No Yes Yes Yes Yes No No Yes }>3 loose stools per day,|>3 stool per day lwatery like rice water _|with bloody or pus Doxycycline, [Ciprofloxacin tetracycline Cholera Control * Cholera control is both a matter of emergency response in the case of outbreaks, and a matter of development when the disease is endemic in high risk areas. * Effective cholera prevention and interventions are well known and rely to a great extent on the implementation of integrated am comprehensive approaches that involve activities both inside and outside of the health sectoh including: control’ nced epidemiological and —_ laboratory Enhantwrce to identify endemic areas and detect, ‘and quickly respond to outbreaks cofversal use of safe water and basic sanitation Uarrmunity engagement for behavioural changes cog improved hygiene practices 4 Quick access 0, treatment (Oral Rehydration Qiiion (ORS), which can successfully treat most Sives, and intravenous fluids and antibiotics for severe cases) Protection with safe and effective OCV e, Protect Cholera elimination = any country that reports no confirmed cases with gvidence of local transmission for at least three Consecutive years and has a well-functioning epidemiologic and laboratory surveillance system able to detect and confirm cases. strategies for cholera elimination ~ Ending Cholera: A Global Roadmap to 2030 operationalises the new global strategy for cholera control at the country level and provides a concrete path toward a world in which cholera is no longer a threat to public health. 1. Early detection and quick response to contain ‘outbreaks: The strategy focuses on containing ‘outbreaks—wherever they may occur—through early detection and rapid response, which are itical elements for reducing the global burden of cholera. Through interventions like robust community engagement, strengthening early warning surveillance and laboratory capacities, health systems and supply readiness, and establishing rapid response teams, we can drastically reduce the number of deaths from cholera even in fragile settings. 2, A targeted multi-sectoral approach to prevent cholera recurrence: The strategy also calls on countries and partners to focus on cholera “hotspots”, the relatively small areas most heavily affected by cholera, which experience cases on an ongoing or seasonal basis and play an important role in the spread of cholera to other regions and areas. Cholera transmission can be stopped in these areas through measures _ including improved water, sanitation, and hygiene (WASH) and through use of oral cholera vaccines (OCV). 'n Africa alone, 40 to 80 million people live in sure confirm, cholera hotspots, 3. An effective mechanism of coordination for technical support, advocacy, _ resource mobilization, and partnership at local and Hlobal levels: The GTFCC provides a strong ramework to support countries in intensifying fforts to control cholera, building upon country- led cross-sectoral cholera control programs, and supporting them through human, technical and financial resources. As a global network of organization, the GTFCC is positioned to bring together partners from across all sectors, and offers an effective country-driven platform to support advocacy and — communications, fundraising, inter-sectoral coordination, and technical assistance. + Successful implementation of the Global Roadmap may allow up to 50 percent cost savings compared with the ‘ongoing average yearly cost of continuously responding to emerging cholera outbreaks. Most portantly, the proposed long-term cholera control investments will also significantly reduce the impact of all water-related diseases, while contributing to improvements in poverty, malnutrition, and education, thereby representing a significant step toward the achievement of the Sustainable Development Goals (SDGs) for the world’s poorest people and toward a ‘world free from the threat of cholera. In Nepal + There is establishment of anti-microbial sentinel surveillance system across the country that includes identification of cholera along with plans for use of WHO stockpile cholera vaccine ‘+ Nepal has improved strengthening preparedness by + Strengthening early warning and response team + Expanding health education + Ensuring adequate distribution of ORS + Giving consideration to the provision of oral cholera vaccine in high risk communities (DOVE:- delivering oral cholera vaccine effectively) outbreak ‘in any water borne disease like cholera, typhoid, WASH strategy is applied during floods. WASH stands for Water, Sanitation and Hygiene and Health Education. These three points are must in preventing diny water borne diseases. Taal A753 1. Write short notes on: (2073) a, Management of typhoid at the population level 3 2. Describe the epidemiological triad for typhoid infection and also elaborate the prevention and treatment for typhoid fever. 8 (2072) 3. Explain the underlying reasons why enteric fever remains a public health problem in Nepal. Describe preventive measures of enteric fever. 10 (2069)