Intestinal infection

some of the Intestinal infections and causative agent, their mode of transmission, prevention and control

1. Intestinal infection DEVIPRIYA P V M PHARM

2. CONTENTS Poliomyelitis Hepatitis Cholera. Typhoid Food poisoning Hookworm infection.

3. Poliomyelitis Poliomyelitis is an acute viral infection of the gastrointestinal tract of human beings. The virus can infect the central nervous system in some patients and can produce paralysis in varying degree or even death. Causative agent: Polio virus (Type 1, 2 and 3 ). The virus can survive in water for 4 months and in faeces for 6 months. Inactivated by pasteurization (heat treatment). The virus is found in the faeces and oropharyngeal secretions of infected persons 7 to 10 days before and after the onset of disease

4. Mode of transmission: Faecal - oral route. Spread directly through contaminated fingers or indirectly through contaminated water, milk, food, flies and other articles of daily use. Another route is droplet infection during the acute phase of disease when virus is present in the throat Incubation period: The average incubation period is 7 to 14 days ranging from 3 to 35 days. Clinical spectrum of the disease: (a) Inapparent or subclinical infection: In 95% of cases there are no presenting symptoms. (b)Abortive polio or minor illness In 4 to 8% cases the infection results only in mild self limiting illness

5. (c)Non- paralytic polio It occurs in about 1 % of infections. The patient feels pain in the neck and back and recovers within 2 to 10 days. (d)Paralytic polio In less than 1% of infections. Virus affect the CNS and produces paralysis. Prevention of polio: Immunization is the only effective method for prevention. Oral (Sabin) polio vaccine (OPV) is used for active immunization. It is a live attenuated (activity is reduced) liquid vaccine. The vaccine is stored at 4°C

6. 3 drops of OPV are given orally with each dose of DPT vaccine at the age of ½ months, 2 ½ months and 3 ½ months. Booster dose given at the age of 18 to 24 months. One dose of OPV is given (Zero polio) at birth along with BCG vaccine. Eradication of polio: The eradication strategy includes the diagnosis of acute flaccid paralysis cases as early as possible, laboratory conformation and information to WHO within 48 hours Pulse Polio Immunization (PPI) is given for children below 3 years. All disease causing virus strains are suppressed and replaced by vaccine virus strain OPV is heat sensitive

7. Cold condition is maintained from manufacturing to use. Coloured vaccine vial monitors (VVM) are used to know the potency of vaccine. The wrapper of the vial has a blue circle with a white square in it The vaccine is potent till the square remains white. When it turns blue and matches with the colour of the outer circle, the vaccine should be discarded.

8. Acute Flaccid Paralysis (AFP) survey is also done. If the stool examination is positive for AFP, search for more cases and stool examination of suspected cases are done. Information is send to WHO immediately. Confirmed cases should be examined for residual paralysis and advised rehabilitation Acute Flaccid Paralysis (AFP) : Sudden onset of weakness or paralysis in a previously normal limb over a period of 15 days in a patient aged less than 15 years

9. HEPATITIS HEPATITIS A: Infectious hepatitis or epidemic jaundice. It is an acute infectious disease of liver which starts with non specific symptoms like fever chills, headache, fatigue, generalized weakness and pains followed by anorexia, nausea, vomiting, dark urine and jaundice Causative agent: Hepatitis A virus (HAV) (an enterovirus of picornaviridae family). It multiplies in hepatocytes (liver cells). The virus is found in abundance in faeces of the patient during early acute phase of the disease and later part of the incubation period

10. Mode of transmission (a) Faecal or oral route: It is the major route of transmission. Transmitted directly from person to person or indirectly by using contaminated water, milk or food. (b) Parenteral route: Through needles, blood or blood products (c) Sexual transmission: Mainly among the homosexual man Incubation period: Usually 25 to 30 days ranging from 15 to 45 days

11. Prevention: The spread can be reduced by promoting personal and community hygiene such as hand washing after toilet and before meals, sanitary disposal of excreta, safe water supply and proper sterilization of needles and syringes. Gamma globulins given exposure to virus or early during the incubation period will prevent or attenuate a clinical illness 4 inactivated Hepatitis A vaccines are now available. 2 doses are recommended at an interval of 6 to 18 months A combined vaccine containing inactivated Hepatitis A and recombinant Hepatitis B vaccines is also available (total 3 doses- zero, one and six months) it is contraindicated in children below one year

12. HEPATITIS B: Serum Hepatitis Causative agent: Hepatitis B virus (HBV) It is a complex 42 nm double shelled DNA virus . Three morphological forms of HBV are found in serum (a)Small spherical particles of diameter 22nm stimulates production of antibodies. (b) Tubules of varying size (c) Dane particles which correspond morphologically to HBV Mode of transmission: (a)Parenteral route: Blood borne infection transmitted by infected blood and blood products through transfusion, dialysis, contaminated syringes and needles, pricks of skin, ear or nose piercing etc

13. (b) Parenteral transmission: From carrier mother to babies (c)Sexual transmission: Common in male homosexuals. (d)Other routes: Transmission by blood sucking arthropods like mosquitoes and bed bugs. Incubation period: 45 to 180 days Clinical features: Signs and symptoms similar to viral hepatitis. Infection is followed by chronic liver disease which can further progress to primary liver cancer

14. Prevention: There is no specific treatment for viral hepatitis (a)Hepatitis B vaccine Formalin inactivated sub unit viral vaccine for intramuscular use. Given in 3 doses of 1 ml each (0.5 ml in children below 10 years). Second dose given one month after first dose. Third or booster dose is given 6 months after first dose (b)Hepatitis B immunoglobulin( HBIg ) Given immediately after accidental inoculation withih 6 to 48 hours. 2 doses given in an interval of one month , contains 0.05 to 0.07 ml of HBIg / kg body weight It produces passive immunity and provide protection for 3 months (c)Passive active immunization: Simultaneous use of HBIg and hepatitis B vaccine (d)Other measures. All blood donors should be screened for HBV infection Use only sterilized needles and surgical instruments. Carriers should not use the shaving brush or razor of other persons

15. DELTA HEPATITIS: Occurs in association with hepatitis B infection. Mode of transmission and control are identical to hepatitis B Immunization against hepatitis B also protects Delta hepatitis HEPATITIS NON-A, NON-B (HNA, NB): Hepatitis which is not caused by agents that are not related serologically to HAV or HBV. Diagnosis of HNA NB is made by the absence of both HAV IgM and HBV IgM . Hepatitis virus C is transmitted parentrally Hepatitis virus E is transmitted through water

16. CHOLERA Cholera is an acute diarrheal disease. Causative agent: Vibrio cholera 0 group or Vibrio cholera 01 Mode of transmission: Faecally contaminated water, contaminated food and drinks or by direct contact (through contaminated fingers) Incubation period: 1 to 2 days ranging from few hours to 5 days

17. Prevention and control: Based on the “ Guidelines of Cholera Control ” by WHO Verification of the diagnosis: investigate all cases of diarrhoea for the presence of V. cholera in stool Notification: notify the cases to the local authority for action and further transmission of information Early case finding: early detection is important for treatment and prevention Establishment of treatment centres : to avoid delay in treatment Rehydration therapy: By oral or intravenous Sodium chloride 3.5 gms Sodium bicarbonate 2.5 gms Potassium chloride 1.5 gms Glucose(Dextrose) 20 gms Portable water 1 litre

18. Instead of sodium bicarbonate, trisodium citrate dihydrate is used to make more stable product. A simple mixture of table salt (10 gm) and sugar (40 gm) is dissolved in 1 litre of water and given to patient in absence of rehydration solution Intravenous rehydration therapy: For patients who are unable to drink Ringer’s lactate is used (Dose- 110 ml/kg body weight) Adjuncts to therapy: Tetracycline 500 mg 4 times a day for 3 days Vaccination: Cholera vaccine is a suspension of killed vibrios preserved in phenol.

19. For primary immunization 2 doses (each of 0.5 ml) are given subcutaneously at an interval of 4 to 6 weeks. Booster doses are recommended every 6 months. 2 types of oral cholera vaccines are also available. (1) Live attenuated single dose vaccine (2) Combination of cholera vibrio with a recombinant B subunit of cholera toxin. 2 oral doses of the vaccine are given 10 to 14 days apart Other measures: Sanitation measures (water control, excreta disposal, food sanitation and disinfection) Health education etc

20. TYPHOID Typhoid fever is characterized by a continuous fever for 3 to 4 weeks, relative bradycardia , with involvement of lymphoid tissue and constitutional symptoms. Causative agent: Salmonella typhi Salmonella paratyphi A and Salmonella paratyphi B can also cause the disease. Mode of transmission: Transmitted through faecal - oral route or urine-oral route. Direct transmission through contaminated hands or fingers is also possible. Indirect transmission occurs by ingestion of contaminated water, milk or food or through flies

21. Prevention: Prevention is done by control of reservoir, control of sanitation and by immunization. Immunization against typhoid is done by anti-typhoid vaccine . TAB vaccine is used in India TAB vaccine contains Salmonella typhi(1000 million), Salmonella paratyphi A (500 to 750 million)and Salmonella paratyphi B (500 to 750 million) organisms per ml. Primary immunization is done by given subcutaneously 2 dose each of 0.5 ml at an interval of 4-6 weeks. Booster dose are needed every 3 years. Oral typhoid vaccine: Live attenuated oral typhoid is also available in capsule for children above 6 years and adults. Capsules are ingested on days 1, 3 and 5. Provide immunity for 3 years, so booster dose is needed after 3 years

22. FOOD POISONING Food poisoning is an acute gastroenteritis caused by ingestion of food or drink contaminated either with bacteria or other toxins or inorganic substances and poisons derived from plants and animals. Disease is characterized by ingestion of common food, attack of many person at the same time Types of food poisoning: Non bacterial and Bacterial. Non bacterial is caused by chemicals such as fertilizers, pesticides, cadmium, mercury etc The Bacterial food poisoning is caused by the ingestion of food contaminated by living bacteria or their toxins

23. The bacterial food poisoning can be Salmonella food poisoning, Staphylococcal food poisoning , Botulism (caused by exotoxin of Clostridium botulinum ), Clostridium perfringens food poisoning and Bacillus cereus food poisoning. Prevention and control: (1)Food sanitation (2)Refrigeration (3)Surveillance. Food sanitation: This include inspection of food and of food animals. The animals should be free from infections. Personal hygiene of individuals involved I handling, preparation and cooking of food need care. Milk and milk products should be pasteurised (heat treatment) Foods handlers must be educated in matters of clean habits and personal hygiene

24. Refrigeration: Proper temperature control is needed. Food should be kept in warm pantries to avoid the multiplication of bacteria. Cook and eat the same day can avoid food poisoning. Cold is bacteriostatic at temperature below 4°C Food stored at 4°C to 40°C is in the danger zone of bacterial growth Surveillance: Food samples must be obtained from the food establishments periodically for laboratory analysis

25. HOOKWORM INFECTION ( Ancylostomiasis ) Hookworm infection is the infection caused by Ancylostoma duodenate or Necator americans . Mixed infection can occur in the same person Causative agent: The adult worm lives in the jejunum where they attach themselves to the villi . Length of male worm is 8 to 10 mm and that of female is 10 to 13 mm. The egg is thin shelled and oval. 2 to 8 lobes may be seen in the yolk of eggs. Eggs are passed n the faeces in thousands

26. Eggs

27. Mode of transmission: In warm moist soil the larvae develop and reach the filariform infective stage. These larvae enter the body by penetrating the skin. After entering the blood via skin the larvae are carried to the lungs. Fro their they ascend the alveoli and are swallowed and develop in the small intestine. They reach maturity in 4 to 7 weeks after infection. The larvae can also enter directly into the intestine by ingestion of fruits and vegetables contaminated by them. Man is the only host for this worm Effect of the disease: The infection results into abdominal pain and iron deficiency anaemia

28. Prevention: Prevention is done by sanitary disposal of faeces, chemotherapy, correction of anaemia and by giving health education. Chemotherapy: Several effective drugs are used: Mebendazole : 100 mg dose orally twice a day for 3 days Albendazole : single dose of 400 mg Pyrantal :single dose of 10 mg/kg body weight for 3 days. For treatment of anaemia, ferrous sulphate 200 mg is given orally 3 times a day for 3 months