1. Family Medicine Revision course 26 TH -30 TH JANUARY 2015 1 DR. V.M ALABI. FMCGP, FWACP

2. Cholera is :  An acute bacterial diarrhoeal infection  Caused by gram negative bacterium Vibrio cholerae  Usually ingested from food or water contaminated by faecal material  Affects children and adults  Affects only the small intestine  The enterotoxin secreted in the epithelium of the intestine causes increased activity of adenylate cyclase, resulting in ↑ secretion of water and salts into the lumen of the gut.  Leads to diarrhoea and loss of electrolytes. 2DR. V.M ALABI. FMCGP, FWACP

3.  Cholera originated from the Ganges delta in the India sub-continent  Spread across the world in the 19 th century, along trade routes  Epidemics have occurred in Russia, Western Europe and North America.  Pandemics have occurred in Asia, Africa and Latin America with millions of death.  Seven pandemics have occurred since 1817.  Most resent outbreaks occurred in Haiti (2010) and Nigeria(2011)  In 2011 ;58 countries were affected, 589,854 cases;7816 deaths. 3DR. V.M ALABI. FMCGP, FWACP

4. Cholera:  Water borne disease  Transmitted via contaminated food or water  Found in slums- a disease of poverty  Occurs also in travellers to endemic regions  Associated with seasonal peaks- warm climate.  Between 1995 and 2005, about half a million people were estimated affected in war torn areas – DRC of Congo and Rwanda.  Large outbreaks have occurred in South-East Asia  In 2010, more than 120,000 cases with a case- fatality rate of 2.1% was reported in HaIti. 4DR. V.M ALABI. FMCGP, FWACP

5.  Children under five are more affected in endemic areas  Adult are more affected in less endemic regions.  Clinical presentation is affected by level of nutrition, background immunity and bacterial load  cholera remains a public health problem in developing countries  Attributed to poor /inadequate water treatment, poor personal hygiene and poor sanitary facilities. 5DR. V.M ALABI. FMCGP, FWACP

6.  First outbreak reported in 1971  22931 cases and 2945 death were reported; 12.8% case fatality rate(CFR)  Intermittent outbreaks have been reported between 1972 and 1990  Jan – Dec 2010 a severe outbreak started from the northern part and spread to other part. 41787 cases, 1716 deaths(CFR 4.1%)  222LGAs were affected in 18 states.  Most affected states were Brono, Bauchi and Katsina  2011, between April and October, 22454 cases, 715 deaths (CFR 3.2%) was reported in 195 LGAs. DR. V.M ALABI. FMCGP, FWACP6

7. Vibrio cholerae is- a non spore forming, gram negative,curved rod shaped bacterium. Thrives in brackish water which serves as reservoir for human infection. Attaches to tiny planktonic crustaceans. It feeds on the chitin(sugar polymer found on the shell of the crustaceans) and.. Causes infection when such sea foods are eaten raw or undercooked.  Several serotypes based on their antigenic characteristics are known. DR. V.M ALABI. FMCGP, FWACP7

8. VIBRIO CHOLERA 8DR. V.M ALABI. FMCGP, FWACP

9.  Two main biotypes are known i- Classical ii- El Tor  Both have two serotypes i Inaba ii Ogawa  no major clinical difference is found between the two serotypes or biotypes.  Infection is caused by toxigenic strains of serotype O1 and O139  Most outbreaks/pandemics are caused by serotype O1  O139 is restricted to SE Asia where it was first identified in Bangladesh in 1992.  Non-O1 and non O139 are known to cause diarrhoeal diseases similar to classical cholera but not outbreaks. 9DR. V.M ALABI. FMCGP, FWACP

10. When ingested in food or water :  The organism attaches to the epithelial surface to the small intestines an multiplies fast  Produces potent toxin- a protein with five binding units, which attaches to some receptors on the intestinal wall.  Enzyme adenylate cyclase is activated and breaks down ADP(adenosine diphosphate) to cyclic adenosine monophophste( cAMP).  Interferes with normal fluid and salts movement, ↑ chloride secretion, ↓ NaCl reabsortion.  Results in massive volume of diarrhoea  Watery stools loaded with the organism result  Can result in outbreaks if stool contaminates water sources. 10DR. V.M ALABI. FMCGP, FWACP

11.  Poor sanitary conditions  Displaced population with overcrowding with inadequate basic infrastructures(water and sanitation); found in refuge camps, war torn areas, flood natural disaster areas.  Slums  Poor or inadequate water treatment  Poor personal hygiene  Ingestion of raw or undercooked sea foods  ↓ or lack of stomach acid(hypochlohydria) e.g children  Adults on antacids who lack acid enviroment in their stomach  People with O type blood group ( ? Reason)  Household exposure 11DR. V.M ALABI. FMCGP, FWACP

12.  Most people( 75%) infected are asymptomatic or have a mild disease.  Asymptomatic person may continue to excrete the organism in stool for 7-14 days  About 7-10% develop symptoms  Incubation period is few hour after exposure to 5 days  Passage of profuse, pale and milky stools (rice water)› 1 litre/hour  Or › 20mL/kg in a four hour observation period.  Nausea and vomiting( common in children)  Fever*  Abdominal pain *  Mild- moderate dehydration  Severe dehydration  Dehydration could set in within hours of onset 12DR. V.M ALABI. FMCGP, FWACP

13.  Mild dehydration – fluid loss is <10% of body weight  Severe dehydration –fluid loss ≥ 10% of body wt.  About 80% of people affected develop mild to moderate symptoms  About 20% develop severe dehydration 13DR. V.M ALABI. FMCGP, FWACP

14. Mild – moderate dehydration:  ↑thirst  Dry mucous membrane/ tongue  ↓skin turgor  Irritability  Restlessness  ↓anterior fontanelle in infants  ↓urine output  Sunken eyes 14DR. V.M ALABI. FMCGP, FWACP

15. Severe dehydration leads to circulatory collapse  Hypotension(SBP< 80mmHg)  Weak /Thready pulse  Very dry mucous membrane/tongue  Sunken eyes  Oliguria/anuria  Muscle cramps  Poor skin turgor  Lethargy  Unconsciousness  Hypoglycaemia especially in children- seizures and coma 15DR. V.M ALABI. FMCGP, FWACP

16.  Hypoglycaemia  Hypokalaemia → paralytic ileus;arrhythmias  Muscle cramps  Shock – circulatory collapse  Acute renal failure  Death 16DR. V.M ALABI. FMCGP, FWACP

17.  History - travel - Social hx (contact,family -food ingested ( sea foods?) - drug  Physical examination  Lab tests- FBC -Electrolytes - urea and creatinine - rapid cholera dipstick test of the stool( crystal VC dipstick) 17DR. V.M ALABI. FMCGP, FWACP

18. Other causes of infectious diarrhoea May be difficult to differentiate in early stages  Shigella - bloody stool  Enterohaemorrhagic E coli - bloody stool  Amoebic diarrhoea – not large volume,bloody  Giardiasis - eggs,live parasites  Food poisoning In all these, stool culture is indicated. 18DR. V.M ALABI. FMCGP, FWACP

19.  Stool microscopy – darkfield/phase contrast- microscopy is the initial test- shows curved bacilli  Stool gram stain  Stool culture with isolation of the organism and identification of serotype O1 or O139 is the gold standard colonies appear typically as yellow shiny colonies on thiosulphate citrate bile salt sucrose(TCBS) 19DR. V.M ALABI. FMCGP, FWACP

20. The goal is:  Evaluate patients individually  Prompt fluid and salt replacement  Prompt treatment 20DR. V.M ALABI. FMCGP, FWACP

21.  Start ORS solution immediately for patients that can drink  Offer the ORS frequently  Measure amount drunk and fluid lost in stool and vomitus= input/output  Frequent small sips for patients that vomit/ ORS by NG tube NB: ORS solution must be prepared with safe water (boiled or treated with chlorine). 21DR. V.M ALABI. FMCGP, FWACP

22. Amount of ORS (in mls) can be calculated for each patient.  Multiply patient’s weight by 75 A rough guide is to give older children and adults 100ml ORS every five minutes until patient is stable.  However if more fluid is requested by patient, it should be given  NB: mothers should continue breastfeeding infants that are affected.  Assess patient one hour after commencement of treatment  Thereafter two hourly until rehydration is complete. 22DR. V.M ALABI. FMCGP, FWACP

23.  Approximate amount of ORS solution to give in the first 4 hours to patient with some dehydration.  Use patient’s age where the weight is not known. 23DR. V.M ALABI. FMCGP, FWACP

24. FLUID REQUIREMENT. 24DR. V.M ALABI. FMCGP, FWACP

25.  Patients with uncontrollable vomiting, severe dehydration who cannot drink should be rehydrated intravenously  Ringer’s Lactate Solution is the best fluid  Normal saline is acceptable, but it does not correct acidosis  Start intravenous fluid immediately  If patient can drink, give ORS solution while i.v drip is set up  NB: Give 100ml/kg Ringer’s Lactate Solution as divided below. 25DR. V.M ALABI. FMCGP, FWACP

26. AgeFirst 30ml/kg in Then 70ml/kg in Infants (<12mons) 1 hour5hours Older(> 1yr) 30mins21/2 hours Repeat once if radial pulse is still very weak or. undetectable 26DR. V.M ALABI. FMCGP, FWACP

27.  *Standard WHO approved ORS contains Na+ 75, K+ 20,Cl- 65, citrate 10 and glucose 75(all in mmol/L) with osmolality of 245mOsmol/L  Monitor patient closely  Reassess the patient 1-2hourly and continue rehydration  If hydration is not improving, give infusion more rapidly 200ml/kg may be required in the first 24hours  As soon as patient can drink give ORS solution (about 5ml/kg/hour 27DR. V.M ALABI. FMCGP, FWACP

28.  Patient with high rate of purging (e.g.>1L/hour) should be nursed in isolation  Appropriate disinfecting agent must be used to clean up  As soon as patients are able to eat, normal diet should be started. 28DR. V.M ALABI. FMCGP, FWACP

29.  Thirst subsides  Pulse is stronger  Skin turgor returns  Urine has been passed 29DR. V.M ALABI. FMCGP, FWACP

30.  Patients with high purging rate benefit from antibiotics  Antibiotic are recommended in moderately and severely ill patients who continue to pass large volume of stool in spite of rehydration.  Oral antibiotic reduce the volume and duration of dirrhoea  Choice of antibiotics should be based on available drugs and individual case consideration  ANTIBIOTICS SHOULD BE GIVEN ORALLY. 30DR. V.M ALABI. FMCGP, FWACP

31. Classification of patients First choiceSecond choice Adults (non-pregnant) Doxycycline:300mg p.o – in a single dose Ciprofloxacin : 1000mg as a single dose Azithromycin 1gm as a single dose Tetracycline 500mg qds x 3 days Erythromycin 500mg qds x 3 days Pregnant women Azithromycin 1gm – single dose Erythromycin 500mg qds x 3 days. Children ≥ 12mons and capable of swallowing pills and oral tablets Azithromycin oral suspension 20mg/kg – single dose Erythromycin 12.5mg/kg qds x 3 days. Doxycycline 2- 4mg/kg- single dose Doxycycline 2- 4mg/kg –single oral dose(chidren > 8yrs) Tetracycline :12.5mg/kg qds x 3days. (For children > 8yrs) 31DR. V.M ALABI. FMCGP, FWACP

32. Classification of patients First choice Second choice Children < 12mons old and others unable to swallow pills and /or tablets Azithromycin oral suspension, 20mg/kg – single dose Doxycycline 2- 4mg/kg –single oral dose (chidren > 8yrs) Tetracycline :12.5mg/kg qds x 3days. (For children > 8yrs) ZINC SUPPLEMENT NB: Administration of zinc in children with diarrhoea caused by infection significantly reduces the duration and severity of diarrhoea. It should be taken until recovery. Dose : 10-20mg/day. Zinc opposes the cholera toxin induced electrolyte secretion. 32DR. V.M ALABI. FMCGP, FWACP

33.  In developed countries where proper sewage and water treatment exist, cholera is rare except cases related to travel outside the countries  Basic precautions protects from cholera  Frequent hand washing with soap especially after using the toilet and before handling food  Use of alcohol based sanitizer if soap is not available  Drink safe water- boiled or disinfected  Food should be well cooked and eaten hot  Avoid food vendors  Avoid raw or under cooked sea foods  Avoid salads, fruits that can’t be peeled.  Avoid dairy products(unpasteurised milk, ice cream) 33DR. V.M ALABI. FMCGP, FWACP

34.  Main goal is to reduce death by  Prompt treatment  Conyrol spread of the disease  Provision of basic amenities( -safe water - proper sanitation - Safe food handling practices  Health education  Improved self hygiene 34DR. V.M ALABI. FMCGP, FWACP

35.  Two types of oral vaccine are available  Both are whole cell killed vaccines  Both provide > 50% protection which last for two years.  Both are prequalified and licensed by WHO in >60 countries - Dukoral- provides short term protection of 85-90% against V. cholerae O1 Dukoral is given in 150ml of water - Shancol – provides long term protection against V. cholerae O1 and O139 in children < 5years.  Both are given in two doses between 7days and 6 weeks apart NB: Parenteral vaccine is not recommended by WHO because its protective efficacy is low and the severe adverse effects associated with it. 35DR. V.M ALABI. FMCGP, FWACP

36.  Cholera is an acute diarrhoea disease  Spread through contaminated water  Causes severe diarrhoea and dehydration  Fatal within hour if left untreated  Can be successfully treated with ORS in upto 80% of cases  Easily treated  Provision of safe water and proper sewage disposal will reduce the outbreaks  oral vaccines are available DR. V.M ALABI. FMCGP, FWACP36

37. THANK YOU DR. V.M ALABI. FMCGP, FWACP37